UNDERSTANDING RADIATION IN OUR WORLD · UNDERSTANDING RADIATION IN OUR WORLD 9 Radiation as a Part of Our Everyday Lives Radiation is all around us, every minute of every day. Some

UNDERSTANDINGRADIATION

IN OUR WORLD


IN OUR WORLD

COVER 2

National Safety Council’s Environmental Health Center1025 Connecticut Ave., NW Suite 1200

Washington, DC 20036202/293-2270

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IN OUR WORLD


IN OUR WORLD

A Publication of the National Safety Council’s Environmental Health Center

1025 Connecticut Ave., NW Suite 1200Washington, DC 20036

This guidebook was produced with funds from the U.S. Environmental Protection Agencyunder cooperative agreement no. 82486201. The contents of this document do not neces-sarily reflect that agency’s views or policies.

Permission to reproduce portion of this guidebook is granted with use of the accompanyingcredit line: “Reproduced from Understanding Radiation in Our World, with permissionfrom the Environmental Heath Center of the National Safety Council.”

This guide benefited substantially from prepublication review by a range of experts, buttheir review does not necessarily connote their or their organizations’ endorsement of orsupport for all aspects of this guide.

For information on ordering additional copies of this guide or copies of the supplementalmaterials, please visit the Environmental Health Center website:http://www.nsc.org/ehc/rad.htm or call 202/293-2270.

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Table of Contents

U N D E R S T A N D I N G R A D I A T I O N I N O U R W O R L D

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Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Radiation as Part of Our Everyday Lives . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Dangers of Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9About this Guidebook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Chapter 1:What is the Nature of Radiation? . . . . . . . . . . . . . . . . . . . . . . . . . 11Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Types of Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Structure of Atoms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Effects of Ionizing Radiation on Atoms . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Forms of Ionizing Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Radioactive Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Half-Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Types and Sources of Ionizing Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Chapter 2:Where Does Radiation Come From? . . . . . . . . . . . . . . . . . . . . . . 17Sources of Ionizing Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Measuring Radiation Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Natural Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Manmade Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Sources of Nonionizing Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Chapter 3:What are the Benefits and Risks of Ionizing Radiation? . . . . . . 25Benefits of Ionizing Radiaton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Medical Uses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Nuclear Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Agriculture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Food Irradiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Consumer Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31The Space Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Sea Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31The Risks of Ionizing Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Measuring Human Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32


6

Studying Radiation’s Effects on Humans . . . . . . . . . . . . . . . . . . . . . . . . . . 33Human Health Effects of Ionizing Radiation . . . . . . . . . . . . . . . . . . . . . . . 33Health Effects of Radon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Radiation-Related Health Effects from Living

Near Nuclear Power Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Accidental Releases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Determining Your Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Determining Levels of Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Balancing the Benefits and Risks of Radiation . . . . . . . . . . . . . . . . . . . . . . 43Governmental Risk Assessments and Standards . . . . . . . . . . . . . . . . . . . . . 43Individual Judgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Society’s Judgments, Pro and Con . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Future Prospects for Nuclear Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Chapter 4: How Are Radioactive Wastes Managed? . . . . . . . . . . . . . . . . . . . . 45Radioactive Waste Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45The Search for Permanent Disposal Solutions . . . . . . . . . . . . . . . . . . . . . . 45Radioactive Waste Cleanup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Transporting Radioactive Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Chapter 5: How Is the Public Protected From Radiation? . . . . . . . . . . . . . . 57Government Responsibilities in Protecting the Public . . . . . . . . . . . . . . . . 57How You Can Limit Your Radiation Exposure . . . . . . . . . . . . . . . . . . . . . . 58Government Controls on Exposure to Radiation . . . . . . . . . . . . . . . . . . . . 59Controlling Medical Exposures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Controlling Exposure to Radon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Monitoring Radiation Levels in the Environment . . . . . . . . . . . . . . . . . . . 62Controlling UV Radiation Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62Controlling Occupational Exposures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62Responsible Federal Agencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Federal, State and Local Government Functions . . . . . . . . . . . . . . . . . . . . 67Other Roles in Managing Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Appendices

Appendix A: Glossary of Radiation Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Appendix B: List of Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Appendix C: Additional Resources and References . . . . . . . . . . . . . . . . . . . . . . . . 83

Appendix D: Brief Chronology of Radioactive Materials and Radioactive Waste in the United States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

Appendix E: Major Uses of Radioisotopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Preface


7

“Radiation.” What images come to our minds?

✔ “Duck and cover” drills in schools in the 1950s, and orders to scurryunder our desks.

✔ Waste drums and protests over waste disposal sites.

✔ Radon, the naturally-occurring radioactive gas present in manyhomes across the country.

✔ Medical X-rays or radiation therapy for cancer.

✔ Ultraviolet radiation from the sun.

These are just a few examples of radiation, its sources, and uses.

Radiation is part of our lives. Natural radiation is all around us and manmade radiation ben-efits our daily lives in many ways.

Yet radiation is complex and often not well understood. Understanding radiation and its risksand benefits can help us—as individuals and as a society—to make informed decisions aboutthe use of radiation and actions to protect ourselves from possible harm.

Understanding Radiation in Our World attempts to explain the basics of radiation and some ofits potential complexities and nuances, and to provide some perspective on its potential risksand benefits. The Guide has a companion set of videos: “A Look at Radiation” and“Managing Radiation.”

This guide is one of the continuing series of “plain talk” guides produced by the NationalSafety Council's Environmental Health Center (EHC). The goal of the series is to help thepublic better understand, and therefore better manage, some of the leading environmentalrisks we face day in and day out.

Bud WardExecutive Director, Environmental Health CenterNational Safety Council

March 2001

BLANK

IIntroduction


9

Radiation as a Part of OurEveryday LivesRadiation is all around us, every minute ofevery day. Some radiation is essential to life,such as heat and light from the sun. Wecould not exist without it. Some radiationinforms and entertains us, through videosignals and sounds from television sets andradios. As used in medicine, radiation helpsus diagnose and treat diseases and savelives. Yet it can also pose serious risks.

Radiation is energy that comes from bothnatural sources, and manmade sources thatprovide many of the conveniences andnecessities of modern living.

Natural RadiationWe are exposed to radiation from numerousnatural background sources: the atmos-phere, soil and water, food, and even ourown bodies. On average, much more of our exposure to radiation comes from these natural sources than from manmadesources.

Manmade RadiationA smaller but increasing amount of theradiation we are exposed to is manmade.Modern technologies, for example, use radi-ation to:

• Diagnose and treat medical problems

• Communicate over long distances

• Generate electricity for our domestic andindustrial needs

• Eliminate harmful bacteria from food

• Conduct basic and applied research

Dangers of RadiationManaging exposure to radiation is a majorconcern to citizens and government offi-cials in the United States and around theworld.

• Excessive exposure to high-energy (ion-izing) radiation can trigger changes inbody cells leading to cancer, birthdefects, and—in extreme cases—cata-strophic illness and death.

• Too much exposure to the sun’s rays candamage eyes and burn skin, causingcataracts or cancer.

Several events and circumstances continueto influence public perceptions about radi-ation dangers.

• Pictures and stories of the terrible effectsof massive radiation doses to the peopleof Hiroshima and Nagasaki have createda lasting fear of radiation.

• Development and testing of nuclearweapons have left a legacy of pollutionthat in the United States alone will takedecades and billions of dollars to cleanup.

• Accidents at two nuclear power plants—Three Mile Island in Pennsylvania andChernobyl in the former SovietUnion—introduced the term “melt-down” to popular culture and raised con-tinuing questions about the safety ofnuclear power.

Introduction

Dangers ofRadiation


10

In addition, uncertainties remain about thesafe disposal of spent fuel from nuclearpower plants and other high-level radioac-tive waste.

About this GuidebookThis guidebook provides information on:

• The nature and sources of radiation

• Benefits and risks involved in use of radiation

• Management of radioactive waste

• Actions by state, federal, and internation-al agencies and by individuals to ensurethat public health is protected from radia-tion hazards

The goal of Understanding Radiation in OurWorld is to help you make informed judg-ments on important radiation issues thataffect your health, your lifestyle, and thewell-being of your family and community:

• How big a risk does radiation pose to us,our families, children, future generationsand the environment?

• How much and what kinds of risk shouldwe tolerate?

• What should we do, as individuals and asa society, to ensure that the benefits ofradiation are not outweighed by the risks?

Introduction

About this Guidebook

1

1U N D E R S T A N D I N G R A D I A T I O N I N O U R W O R L D

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EnergyRadiation is energy—the primal energy ofthe universe, originally created billions ofyears ago. Ionizing radiation is emitted asthe unstable atoms of radioactive materialsconstantly emit alpha, beta, gamma, orother forms of radiation as they “decay” to astable state. This process can take from afraction of a second to billions of years,depending on the material. Radioactivematerials (called radioisotopes or radionu-clides) and the radiation they produce areeverywhere—in the soil, in our food andwater, and in our bodies.

There is an important difference betweenradiation and radioactivity (although theterms are often mistakenly used inter-changeably):

• Radiation is energy in the form of wavesor particles sent out over a distance. (Asimple example is the ripples of waterradiating outward in a pond after a pebbleis dropped into the water.) There aremany different types of radiation.

• Radioactivity is a property of a substance,such as uranium or plutonium, whichemits high-energy (ionizing) radiation.

Radiation travels over distances rangingfrom fractions of a millimeter to billions oflight-years. This energetic quality of radia-tion makes life possible but also presentsthreats of danger and destruction.

To better understand radiation it is impor-tant to remember that:

• Not all radiation is the same.

• Different kinds of radiation affect livingthings in different ways.

Types of RadiationThe most basic distinction scientists makebetween types of radiation is the amount ofenergy involved (Figure 1). Radiation withlower energy levels is called nonionizing;radiation with higher energy levels is calledionizing.

This guidebook sometimes uses the genericterm “radiation” to refer to ionizing radia-tion. Keep the differences between the twotypes in mind as you consider the benefitsand risks of the various types of radiation.

Nonionizing RadiationNonionizing radiation has lower energy lev-els and longer wavelengths. Examples

What is the Nature of Radiation?

What is theNature ofRadiation?

Types ofRadiation

Figure 1.Theelectromagneticspectrum

Source: The Ohio State University Extension

Type Examples

Radio waves, Microwaves,Non-Ionizing Electromagnetic Radiation Infra red (heat), Visible Light (color)

Ionizing Electromagnetic Radiation X-rays, Gamma rays, Cosmic rays

Ionizing Atomic Particle Radiation Beta radiation, Alpha radiation, Neutrons

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Figure 2.Structure of an Atom

include radio waves, microwaves, visiblelight, and infrared rays from a heat lamp.

Our senses can detect some types of non-ionizing radiation: we can see visible light,and feel the burning effects of infrared radiation.

Nonionizing radiation is strong enough toinfluence the atoms it contacts, but notstrong enough to affect their structure. Forexample, microwave radiation is used toheat the water in food by causing watermolecules to vibrate.

Living tissue can generally be protectedfrom harmful nonionizing radiation bydevices such as goggles, protective clothing,and shielding around radiation-generatingequipment. However, concern has beenraised about possible health effects fromnonionizing radiation produced by suchthings as cell phones and electric powerlines. (See Electric and Magnetic Fields,Chapter 2, page 22)

Ionizing RadiationIonizing radiation has higher energy levels.

Examples include X-rays and cosmic rays.

Ionizing radiation has enough energy todirectly affect the structure of atoms of thematerials, including human tissue, which itpasses through. A description of the struc-ture of atoms will help in understanding theeffects of ionizing radiation. (Table 1)

Structure of AtomsAll substances are composed of atoms thatare made up of three subatomic particles:protons, neutrons, and electrons except hydro-gen (which may have no neutrons). Theprotons and neutrons are tightly boundtogether in the positively charged nucleusat the center of the atom, while a cloud ofnegatively charged electrons orbits thenucleus. (Figure 2)

The number of protons in the nucleusdetermines its atomic element. The simplestelement, hydrogen, has only one proton inits nucleus. Oxygen has eight protons.Heavier elements, such as uranium and plu-tonium, have more than 90 protons.

Elements may have various isotopes. An

Source: U.S. Environmental Protection Agency

Table 1: Basic Types of Radiation

nucleus:contains protons(+) and neutrons

electrons (-)

What istheNature ofRadiation?

Structure ofAtoms

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isotope is one of two or more atoms thathave the same number of protons but dif-ferent numbers of neutrons in their nuclei.

Most atoms are stable because the nuclearforces holding the protons and neutronstogether are strong enough to overcome theelectrical energy that tries to push the pro-tons apart. (The energy pushing protonsapart is like two magnets with the samecharge that push each other apart.)

When the number of neutrons in thenucleus is above a certain level, however,the atom becomes unstable or radioactive,and some of its excess energy begins toescape. This energy is ionizing radiation.

Effects of Ionizing Radiation onAtomsWhen ionizing radiation passes throughmaterial, such as human tissue, it may“knock” one or more negatively chargedelectrons out of orbit around the nuclei ofatoms of the material. If this happens, thiscauses the atoms to become positivelycharged (ionized). When this occurs in ourbodies, molecules and cells may be dam-aged. The health effects of this damage maybe immediate or appear gradually overmany years.

Forms of Ionizing RadiationIonizing radiation can take two differentforms:

• Electromagnetic waves which spread out inall directions through space at the speedof light.

• High-energy particles which travel throughspace at various rates.

Examples of ionizing radiation include:

• X-rays (used in medicine and for scientific research) and

• Gamma rays (emitted by some materials,including the sun and stars and soil).

Detection of Ionizing Radiation

Ionizing radiation is generally notdetectable by our senses: we cannot see,smell, hear, or feel it. This, together with itsunpredictable health effects, may explainwhy it causes so much anxiety.

However, ionizing radiation is relativelyeasy to detect and measure using electronicequipment. Instruments such as Geigercounters can detect radiation and help ustrack the amount of radiation exposure.These instruments can tell us if we are tooclose to a source that can harm us and warnus of a release of radiation.

Radioactive DecayWhen the nucleus of a radioactive isotopedecays, emitting ionizing radiation, thenucleus is transformed into a different iso-tope, called a decay product. The new iso-tope may be stable or unstable. If it is unsta-ble, it will continue to decay, changing itsnucleus and emitting more ionizing radia-tion. Several decays may occur before a sta-ble isotope is produced. (Figure 3)

What isthe

Nature ofRadiation?

Radioactive Decay

Figure 3.Radioactive Decay


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Half-lifeThe half-life is the time it takes for one-halfof a radioactive isotope’s atoms to decay.

For example, suppose that several atoms ofa radioactive isotope with a half-life ofthree hours were isolated and observed.After three hours, one-half of thoseradioactive atoms would remain. The otherhalf would have decayed into different iso-topes. After three more hours, only half ofthe remaining radioactive atoms (one-fourth of the original number) wouldremain unchanged.

The half-life can vary substantially fromone isotope to another, ranging from a frac-tion of a second for plutonium-214, to 8days for Iodine-131, to 24 thousand yearsfor plutonium-239, to billions of years foruranium-238.

The half-life of an isotope determines thelongevity of its radioactivity. The longerthe half-life, the more atoms it takes to givea certain amount of radioactivity. However,the half-life of a radioactive material is nota direct measure of the risk associated withthe material. (See Determining Levels ofRisk, Chapter 3, page 41.)

Types and Sources of Ionizing RadiationThe major types of ionizing radiation emitted as a result of radioactive decay arealpha and beta particles and gamma rays.

(Figure 4) X-rays, another important type ofradiation, arise from processes outside of thenucleus.

Alpha Radiation

An alpha particle is composed of two neu-trons and two protons in a tight positively-charged bundle that has escaped from thenucleus of a heavy radioactive element,such as uranium or radium, during radioac-tive decay.

Alpha radiation is relatively slow-moving,has little penetrating power and can bestopped by a single sheet of notebook paper or the dead outer layer of skin tissue.(Figure 5) Therefore, alpha-emittingradioisotopes are not usually a hazard outside the body.

However, when alpha-emitting materialsare ingested or inhaled, energy from the alphaparticles is deposited in internal tissues suchas the lungs and can be harmful. (See TheHealth Effects of Radon, Chapter 3, page37.)

Beta Radiation

Beta particles are fast-moving free electronsemitted during radioactive decay. They canbe either negatively or positively charged.A positively charged beta particle is called apositron.

A beta particle is small—less than 1/7000of the weight of an alpha particle—and ittravels farther through solid material than


Types andSources ofIonizingRadiation

Figure 4.Types ofIonizingRadiation


Alpha Particle(positive charge)

Proton

Neutron

Electron

Energy

Beta Particle(negative charge)

Gamma Ray

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alpha particles. Beta particles can travel sig-nificant distances in air. However, mostbeta particles can be reduced or stopped bya layer of clothing, eyeglasses, or a few mil-limeters of a substance such as aluminum.(See Figure 5)

Although more penetrating than alpha par-ticles, beta particles are less damaging overthe same distance. Some beta particles canpenetrate the skin and cause tissue damageespecially to the eyes. However, both alphaand beta emitters are generally more haz-ardous when they are inhaled or ingested.

Humans can be exposed to beta particlesfrom both manmade and natural sources.Tritium, carbon-14, and strontium-90 areexamples of radionuclides that emit betaparticles upon decay.

Gamma Radiation

Like visible light and X-rays, gamma raysare photons—weightless packets of energy.Gamma rays often are emitted from aradioactive nucleus along with alpha or betaparticles. They have neither a charge normass and are very penetrating.

Most gamma rays can pass completelythrough the human body. This may causeionization and possible health effects in anyorgan of the body. Most gamma rays lose

almost all their energy in a few feet of soil,three feet of concrete, or six inches of lead.

A naturally-occurring source of gamma raysin the environment is potassium-40.Manmade sources include iodine-131 (pro-duced in nuclear reactors, accelerators, andnuclear explosions) and cobalt-60 (also cre-ated in nuclear reactors) which is used infood irradiation. (See Food Irradiation,Chapter 3, page 29.)

X-Rays

X-rays are emitted from processes occurringoutside the nucleus. They have essentiallythe same properties as gamma rays, but aregenerally lower in energy and therefore lesspenetrating than gamma rays. A few mil-limeters of lead can stop X-rays.

X-ray machines are widely used in medicinefor diagnosis and treatment, and in industryfor examinations, inspections, and processcontrols. Because of this heavy use, X-raysare the largest source of manmade radiationexposure. Due to their very short wave-length, X-rays can pass through materials,such as wood, water, and flesh. They can bemost effectively stopped by heavy materialslike lead or by substantial thickness of concrete.

What isthe

Nature ofRadiation?

Types andSources of

IonizingRadiation

Glass orAluminum

Concreteor Lead

Paper

Alpha

Beta

Gamma

Figure 5. Penetrating Power of Different Types of Radiation

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Neutrons

One source of ionizing radiation resultsfrom the release of neutrons during nuclearfission. Neutrons are released during nuclearfission, which may occur spontaneously orduring a nuclear reaction, when a free neu-tron collides with a nucleus.

Neutrons have a neutral electrical charge,so they may be readily absorbed by thenuclei of other atoms, creating new radioac-tive isotopes. Fission fragments and neu-tron-activated material are responsible forthe intense radioactivity on the inside sur-faces of nuclear reactors.

(Material for this chapter is adapted fromWhat Is Radioactive Material and How Does ItDecay? (RER-20) and What Is IonizingRadiation? (RER-21), Ohio State UniversityExtension.)


Types andSources ofIonizingRadiation

2Where Does Radiation Come From?


17

Sources of Ionizing RadiationWhen energy particles and rays are expelledfrom the forces that bind them together inatoms, ionizing radiation is emitted (seeIonizing Radiation, Chapter 1, page 12).This process has been going on since thebirth of the universe. Radiation has alwaysbeen commonplace in our world.

Natural radioactive materials were discov-ered in the 1890s. It was not until 1942that physicist Enrico Fermi and his teamcreated the first manmade radioactive mate-rials in the world’s first nuclear reactor atthe University of Chicago.

Manmade Radiation

In the years since these discoveries, themanmade sources and uses of radiation havemultiplied so that manmade radiation isnow commonplace. We use radiation to:

• Generate electricity,

• Diagnose and treat medical problems,

• Create and improve consumer products,

• Breed more productive and disease resist-ant crops, and

• Conduct a wide range of scientificresearch.

Natural Radiation

However, most of the ionizing radiation weare exposed to consists of natural, or back-ground, radiation:

• Radon gas

• Other terrestrial sources (radioactive ele-ments in rocks, soil, water, and plants)

• Cosmic radiation

• Internal radiation from natural elementsin our bodies (such as radioactive potassi-um) and some foods that contain smallquantities of radioactive elements (suchas radium -226 in eggs, and potassium-40in bananas and some vegetables)

Measuring Radiation ExposureIn the United States, we commonly meas-ure human exposure to potentially harmfulradiation in units called millirem (one one-thousandth of a rem). (See MeasuringHuman Exposure, Chapter 3, page 32.)

On average, each of us receives about 360millirem of radiation each year. About 300millirem, or 82 percent of the total, is natu-ral background radiation (from radon andother natural sources).

The remaining 18 percent of our radiationexposure is from manmade sources (Figure6):

• X-rays and other medical and dental pro-cedures

• Consumer products (such as cigarettes,smoke detectors, color televisions)

• Operation of nuclear power plants

• Manufacture of nuclear weapons

• Fallout from past atmospheric nuclearweapons testing

WhereDoes

RadiationComeFrom?

MeasuringRadiationExposure

2


Natural SourcesEverything on Earth is exposed to a con-stant barrage of naturally occurring ionizingradiation from the sun, cosmic rays, andradioactive elements in the Earth’s crust.The primary radioactive elements in theEarth’s crust are uranium, thorium, potassi-um, radium, and their radioactive decayproducts or derivatives.

Radon

Radon is a naturally occurring gas formedfrom the radioactive decay of uranium-238in rock and soil. Radon is colorless, odor-less, tasteless, chemically inert, and radioac-tive. Radon also decays, emitting ionizingradiation in the form of alpha particles, andtransforms into decay products, or “proge-ny” radioisotopes. The half-life of radon isabout four days. Unlike radon, the progenyare not gases, and can easily attach to andbe transported by dust and other particles inair. The decay of progeny continues untilstable, non-radioactive progeny are formed.At each step in the decay process, radiationis released. Radon accounts for more thanhalf (an average of 55 percent) of the radia-tion dose we receive each year and is thesecond leading cause of lung cancer, aftercigarette smoking, in the U.S.

Radon moves through air or water-filledpores in the soil to the soil surface and

enters the air, while some remains belowthe surface and dissolves in ground water(water that collects and flows under theground's surface). Radon has been found indrinking water from public ground watersupplies in many states across the country.In the outside open air, most radon dilutesinto relatively low concentrations (about0.4 picocuries per liter of air, abbreviatedpCi/L).

Radon becomes a serious public healthproblem when high levels are found inindoor air where people can breathe it – inhomes, schools, and other buildings. Radonin the soil can seep through the basementor ground floor through cracks in a founda-tion or construction joints and build upindoors to levels substantially higher thanoutdoor air levels. (Figure 7) Indoor radonhas become more of a problem in recentyears because new homes are built more air-tight and Americans now spend an averageof about 90 percent of their time indoors.

Similar homes in the same neighborhoodmay have very different radon readingsbecause they are not all built on exactly thesame piece of ground and construction isnot identical. High levels of indoor radon(above EPA action level of 4 pCi/L forradon in indoor air) have been found in allkinds of homes throughout the U.S. Insome parts of the country, indoor radon lev-els have been measured at hundreds of pic-ocuries per liter and higher.

EPA and the Office of the U.S. SurgeonGeneral recommend that citizens take stepsto reduce indoor radon levels to below 4pCi/L. EPA’s National Residential RadonSurvey completed in 1991 indicates thatmore than six percent of all homes nation-wide have elevated radon levels, approxi-mately one in every 15 homes (or six mil-lion homes) nationwide.

Radon can also be a problem in schools andother buildings. EPA’s National SchoolRadon Survey found that 20 percent of theschools nation-wide (about 15,000 institu-tions) have at least one school room with aradon level greater than 4 pCi/L.


WhereDoesRadiationComeFrom?

Natural Sources

18

Source: National Council on Radiation Protection and Measurements

Radon55%

Medical X-rays 11%

Internal11%

Terrestrial8%

Terrestrial 8%

Cosmic8%

Nuclear Medicine

4%

Consumer Products

3%

Other<1%

Figure 6. Sources of radiation exposure

2


Although most of radon exposure indoorscomes from soil, radon dissolved in tapwater can be released into indoor air whenit is used for showering, washing or otherdomestic uses, or when heated before beingingested. This adds to the airborne radonindoors. It is estimated that this sourceaccounts for less than five percent of thetotal indoor air concentration in housesserved by ground water sources. Because ittakes about 10,000 pCi/L of radon dissolvedin water to produce about one pCi/L ofradon in household air, the levels of radonin drinking water need to be significantlyelevated to substantially contribute to thelevel of radon in the indoor air.

Other Terrestrial Sources

Other naturally occurring radioactive mate-rials in the Earth’s crust, such as thorium,potassium, and radium, contribute abouteight percent of our annual exposure toradiation. Radiation levels from thesesources also vary in different parts of thecountry.

Cosmic Radiation

Cosmic radiation from outside the Earth’satmosphere includes high-energy protons,electrons, gamma rays, and X- rays that hitthe Earth as it moves through space.Fortunately, the Earth’s atmosphere absorbsmuch of the energy from cosmic radiation.

About eight percent of our annual exposurecomes from cosmic radiation. However, cos-mic radiation increases at higher altitudes,roughly doubling every 6,000 feet. Forexample, the exposure to cosmic radiationis about twice as high in Denver as it is inChicago.

Internal Radiation

About 11 percent of the average person’stotal annual exposure comes from radioac-tivity within our own bodies. Radioactivematerials in the air, water, and soil areabsorbed in food and then by the body’sown tissues.

Potassium and carbon are two of the mainsources of internal radiation exposures.

They enter our bodies through the food weeat and the air we breathe.

• Potassium, essential to life, is distributedthroughout our bodies. A small portion(about one one-hundredth of a percent)of natural potassium consists of a naturally radioactive isotope called potassium-40. This isotope is the chiefradioactive component in normal foodand human tissue.

• Carbon-14, a radioactive isotope of car-bon created by cosmic radiation, makesup a small fraction of all carbon in ourbodies.

Manmade SourcesAs our use of radiation increases, so doesour exposure to ionizing radiation frommanmade sources. Lifestyle choices, includ-ing house construction, air travel, andsmoking, also affect the level of our expo-sure. Airline crews experience greater expo-sures than people who live at sea levelwhere they are protected by a thicker blan-ket of atmosphere.

Medical and dental X-rays account for mostof the exposure from manmade sources, anaverage of about 11 percent of our totalannual exposure.

Consumer products such as color televisionsets, video displays, and smoke detectorsaccount for another three percent of annualexposure.


WhereDoes

RadiationComeFrom?

ManmadeSources

19

Source: US Environmental Protection Agency

Figure 7. Radon Routes into a Home

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20

Other potential sources of small amounts ofradiation are:

• Mining and agricultural products, and ashfrom burned coal,

• Nuclear reactors and their supportingfacilities (uranium mills and fuel prepara-tion plants),

• Federal facilities involved in nuclearweapons production, and

• Fallout from past atmospheric weaponstesting, which peaked in the mid-1960s.

Medicine

About 15 percent of our total average expo-sure to ionizing radiation is from medical X-rays (11 percent) and nuclear medicine(4 percent).

Americans receive about 200 million medical X-rays every year. (Figure 8) X-raysare an important tool in medical diagnoses.

Nuclear medicine involves diagnostic proce-dures such as nuclear tracers, small amountsof radioactive materials that are injectedinto the blood stream to allow monitoringof their progress through the body with aradiation detector. Tracers can help locateblocked or restricted blood vessels anddeveloping tumors.

Nuclear medicine also uses radiation totreat diseases. Precisely targeted cobalt radi-ation, for example, can destroy diseasedcells without damaging healthy cells nearby.Injections into the bloodstream of radioac-tive iodine, which then concentrates in thethyroid, is an effective treatment for hyper-

thyroidism or Graves’ disease, as well asthyroid cancer. (See Medical Uses, Chapter 3, page 25).

Average annual doses from medical applica-tions are about one-sixth the average annu-al dose from background radiation.However, patients undergoing radiation therapy, where radiation is narrowly targetedto affected tissues, can be exposed to levelsmany times higher than background radia-tion. While medical uses of radiation offerimportant benefits, they can also pose risks.

Consumer Products

On average, we receive about three percentof our total radiation exposure from con-sumer products, about 11 millirem per year.

These products include:

• Smoke detectors that use americium-241(Figure 9)

• Lawn fertilizer containing potassium-40

• Cigarettes

• Gas lanterns

• Exit signs

• Natural gas appliances

• Brick or stone houses

• Color television sets

Radiation is also used in the manufacturingprocess for many consumer products. Forexample, cosmetics and medical supplies aresterilized by radiation. Radiation is also usedto help determine the thickness of materi-als, how full cans are before they are sealed,and the quality of the welds in bridges andbuildings. (See Industry and ConsumerProducts, Chapter 3, page 31.)

Nuclear Power

Nuclear power reactors, which use uranium,supply about 20 percent of the electricityused in the United States. (Figure 10)

Nuclear power plant operations account forless than one one-hundredth of a percent(less than one millirem per year) of theaverage American’s total radiation expo-sure. However, workers at nuclear powerplants can receive much higher doses and


ManmadeSources

Figure 8. X-rays Used in Medicine

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21

those who live near power plants mayreceive slightly higher doses.

Nuclear Weapons

For most people, nuclear weapons produc-tion and testing are responsible for onlyvery small amounts of radiation exposure.However, past accidental and plannedreleases have exposed some employees andneighbors of weapons facilities to higherradiation doses.

Fallout from atmospheric testing of nuclear

weapons reached its peak in the mid-1960s.While the effect on background radiation inthe vicinity of these tests was significant inthe days and weeks following an explosion,the effect on world-wide background radia-tion levels has been minor, although meas-urable. The longer half-life fission productsfrom these tests, including cesium-137 andstrontium-90, caused background levels ofradiation around the world to increaseslightly.

Sources of NonionizingRadiationNonionizing radiation is electromagneticradiation that includes:

• Radio waves

• Microwaves

• Infrared light

• Visible light

WhereDoes

RadiationComeFrom?

Sources ofNonionizing

Radiation

Figure 9. Smoke detector

Source: U.S. Department of Energy

Figure 10. Map of U.S. Nuclear Power Facilities

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22

Hazards of Nonionizing RadiationUnlike ionizing radiation, nonionizing radi-ation does not have enough photon energyto remove an electron from an atom.However, it can still be hazardous. Forexample:

• Powerful industrial lasers, which emittightly focused or coherent beams of visi-ble light, can burn through human tissueand even metal.

• Some nonionizing radiation can interferewith the operation of heart pacemakersand other medical devices, as well as crit-ical equipment in aircraft.

• High levels of radio frequency andmicrowave radiation can heat tissue andif the temperature increase is highenough, can adversely affect health.

Electric and Magnetic FieldsExtremely low-frequency electric and magnet-ic fields (EMFs) surround electrical machin-ery, home appliances, electric wiring, andhigh-voltage electrical transmission linesand transformers. (Figure 11)

A good deal of public and governmentattention has been focused in recent yearson the possible health effects of EMFs. Thepublic is exposed to these fields through thegeneration, transmission, and use of electric power. The National Institute ofEnvironmental Health Sciences (NIEHS), abranch of the National Institutes of Health

(NIH), has compiled information on thisissue. (You can get more information onthis and other issues from the NIEHS Website http://www.niehs.nih.gov/emfrapid)

High-voltage power transmission and distri-bution lines have been a major focus ofconcern. Alternating-current (AC) electricity,with a frequency of 60 cycles per second,falls into the extremely low frequency rangeon the electromagnetic spectrum (Chapter 1, Figure 1) and thus has far toolittle energy to cause ionization.

However, AC electric and magnetic fieldscan induce electric currents in conductingmaterials, including human and animal tis-sue. (Direct-current fields, such as theEarth’s magnetic field, do not have thiseffect). The electric current induced in ourbodies may have potential biological andhealth effects.

Evidence of health effects from EMF isinconclusive, although some studies haveindicated a possible link between EMFs andchildhood leukemia and other forms of can-cer. The information available however, isnot sufficient to establish a cause-effectrelationship.

Some studies have reported the possibilityof increased cancer risks, especiallyleukemia and brain cancer, for electricalworkers and others whose jobs require themto be around electrical equipment.Additional risk factors, however, such asexposure to cancer-initiating agents, mayalso be involved.

Some researchers have looked at possibleassociations between EMF exposure andbreast cancer, miscarriages, depression, sui-cides, Alzheimer’s disease, andAmyotrophic Lateral Sclerosis (ALS, orLou Gehrig’s Disease), but the general sci-entific consensus is that the evidence is notyet conclusive.

In June of 1998, a special review panel con-vened by the NIEHS reviewed EMF healthstudies. A majority of the panel found “lim-ited evidence that residential exposure to


Sources ofNonionizingRadiation

Figure 11. Power Lines

2


23

extremely low frequency magnetic fieldsmay increase the risk of childhoodleukemia.” A majority also found limitedevidence that workplace exposure to EMFsmay cause chronic lymphocytic leukemia inadults.

According to NIEHS, “the probability thatEMF exposure is truly a health hazard iscurrently small. The weak epidemiologicalassociations and lack of any laboratory sup-port for these associations provide only mar-ginal scientific support that exposure to thisagent is causing any degree of harm.” TheNIEHS did conclude, however, in its 1999Report to Congress, that extremely-low-fre-quency EMF exposure cannot be recognizedas entirely safe because of weak scientificevidence that exposure may pose a leukemiahazard; the associations reported for child-hood leukemia and adult chronic lympho-cytic leukemia cannot be dismissed easily asrandom or negative findings.

On the positive side, the NIEHS panelfound “strong evidence” that exposure toelectric and magnetic fields can speed thehealing of broken bones.

How can individuals reduce exposure?People concerned about their own exposurecan take several steps to reduce it. Except incertain cases, most people's greatest expo-sure to EMFs may come from sources insidethe home, rather than from power lines out-side it. The NIEHS suggests avoiding stand-ing too close to computers, microwaveovens, televisions, or other devices that mayemit EMFs. People can reduce exposure toEMFs by turning off devices such as electricblankets when they are not in use and bynot keeping devices such as electric alarmclocks too close to the bed. Adults can dis-courage children from playing near highpower lines or electrical transformers.

The distance from a source of EMFs isimportant because the intensity of EMFsdecreases proportionally to the square of thedistance to their source. So doubling yourdistance from a source will reduce exposureto one-quarter of its previous level.

There are no federal health standards governing public exposure to EMFs. A fewstates however, have set standards for trans-mission line electric and magnetic fields.

Radio-Frequency (RF) and CellularPhonesAs hand-held cellular telephones becomeincreasingly popular, people are understand-ably concerned about potential healtheffects from exposure to high-frequencyradio waves. (Figure 12)

The radio waves used by analog and digitalcellular phones are much higher frequencythan the electric and magnetic fields pro-duced by power lines, so their biologicaleffects are different from the possible effectsof EMFs.

Studies have shown that intense exposureto this type of nonionizing radiation cancause heat-related effects such as cataracts,skin burns, deep burns, heat exhaustion,and heat stroke, as well as electrical shock.

As a result of the studies, the United Statesand other countries have established stan-dards to protect workers and the publicfrom the known effects of excess exposureto the radio waves used in telecommunica-tions. The antennas of cell-phone base sta-tions and personal cell phones must complywith these standards.

WhereDoes

RadiationComeFrom?

Sources ofNonionizing

Radiation

Figure 12.Use of Cellular Phones Has Become Part of

Many People’s Daily Lives

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24

Most epidemiological studies have found nosignificant correlation between exposure toradio frequency (RF) radiation and anincreased risk of cancer. One animal studyat the University of Adelaide in Australia,showed that mice genetically predisposed toa type of cancer developed twice as manycancers when exposed to cell phone radia-tion. This study is being repeated at theUniversity of Adelaid and other researchlaboratories to verify the finding.

The Food and Drug Administration (FDA),responsible for protecting the public fromradiation exposure from consumer products,said that “the available science does notallow us to conclude that mobile phones areabsolutely safe, or that they are unsafe.However, the available evidence does notdemonstrate any adverse health effects asso-ciated with the use of mobile phones.”


Sources ofNonionizingRadiation

What Are the Benefits and Risksof Ionizing Radiation?3


25

Since German physicist Wilhelm KonradRoentgen discovered X-rays in 1895, peoplehave invented thousands of new practicaland beneficial uses for ionizing radiation.These uses have improved our quality of lifeand increased our life span.

Ionizing radiation is widely used in:

• Medicine and research

• Industry and manufacturing consumerproducts

• Nuclear power

• Agriculture and food processing

• Development and testing a wide varietyof materials

• National defense (nuclear weapons)

However, our use of radioactive materialsand creation of new sources of ionizing radi-ation add to our total annual exposure andincrease the risks to our health and envi-ronment. Weighing the benefits of ionizingradiation against its risks, and deciding whatlevel of risk is acceptable, is a constantchallenge for scientists, government regula-tors, and each of us as individuals.

This chapter includes the following topics:

• The Benefits of Ionizing Radiation

• The Risks of Ionizing Radiation

• Determining Your Exposure

• Determining Levels of Risk

• Balancing the Benefits and Risks ofRadiation

Benefits of Ionizing RadiationIonizing radiation lets us do many thingsthat are impossible without it, such as iden-tifying broken bones and healing tumors inthe human body, checking for flaws in jetengines, and testing the thickness ofeggshells. Life for many of us would be moredifficult if we were suddenly to stop creatingand using radiation.

Medical UsesThe most common, and one of the earliestuses of radiation, is to diagnose injury anddisease. Roentgen’s discovery of the X-rayallowed physicians to look inside thehuman body without operating. (Figure 13)

What Arethe

Benefitsand Risks

of IonizingRadiation?

Medical Uses

Figure 13.Use of X-ray machine in medicine

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Today, doctors also use radiation in manyways to treat disease. One of every threeAmericans hospitalized each year is diag-nosed or treated using nuclear medicine,totaling more than 11 million procedures ayear. Radiation is also used in 100 millionlaboratory tests each year on body fluids andtissue specimens to aid in diagnosing disease.

Ionizing radiation is widely used to diagnoseand treat cancer, increasing survival ratesand improving patients’ quality of life.Radiotherapy has helped to cure varioustypes of cancer in tens of thousands of peo-ple and temporarily to halt the disease inmany others. About 500,000 cancerpatients in the United States—half of allpeople with cancer—are treated with radia-tion at some point in their therapy.

For example, a promising treatment forleukemia involves arming monoclonal anti-bodies with radioisotopes. The antibodiesare produced in the laboratory and engi-neered to bind to a specific protein intumor cells. When injected into a patient,these armed antibodies bind to the tumorcells, which are then killed by the attachedradioactivity. Normal cells nearby are notaffected.

Other applications of radiation in cancerdiagnosis and treatment include:

• Mammography to detect breast cancer atan early stage when it may be curable

• X-rays or other imaging techniques thatmake needle biopsies safer and moreaccurate and informative

• Monitoring the response of tumors totreatment, and distinguishing malignantfrom benign tumors

• Bone and liver scans to detect the spreadof cancers

• Alleviating or eliminating pain associatedwith prostate or breast cancer that hasspread to the bones

The National Institutes of Health (NIH)lists more advanced medical uses of radia-tion:

• Newer X-ray technologies such as com-puterized tomography (CT, or CAT)scans have revolutionized the diagnosisand treatment of diseases affecting almostevery part of the body. (Figure 14)

• Another scanning technology, positronemission tomography (PET) scanning,involves injecting a small amount of aradioisotope into a patient to show themetabolic activity and circulation in thebrain. PET studies enable scientists topinpoint the site of brain tumors or thesource of epileptic activity and to betterunderstand many neurological diseases.

What AretheBenefitsand Risksof IonizingRadiation?

Medical Uses

Figure 14. CAT scan

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27

• Radioisotopes are used to diagnose andmonitor many diseases effectively andsafely. To show how the disease processalters the normal function of an organ, apatient swallows, inhales, or receives aninjection of a tiny amount of a radioiso-tope. Special cameras reveal where theisotope accumulates in the body (forexample, showing an image of the heartwith both normal and malfunctioning tissue).

• Laboratory tests use radioisotopes tomeasure important substances in thebody, such as thyroid hormones.

• Radiation treatments for thyroid diseases,including thyroid cancer and Graves dis-ease (one of the most common forms ofhyperthyroidism), are so effective theyhave almost totally replaced thyroid surgery.

• Radioisotopes are used in animal studiesto learn how the body metabolizes a newdrug before it is approved by the Foodand Drug Administration (FDA).

• Radioisotopes are used to sterilize hospitalitems to help prevent the spread of dis-eases. Radiation is especially useful forsterilizing such items as sutures, syringes,catheters, and hospital clothing thatwould otherwise be destroyed by heatsterilization. Sterilization using radioiso-topes is particularly valuable because itcan be performed while the items remainin their sealed packages, thus preservingtheir sterility indefinitely.

• Radioisotopes are a technological back-bone of biomedical research. They areused to identify how genes work, and inmuch of the research on AIDS. Between70 and 80 percent of all research at NIHis performed using radiation and radioac-tive materials.

(Adapted from: What We Know AboutRadiation, Office of Communications,National Institutes of Health, April 11,1994.)

IndustryNumerous businesses and industries havefound uses for radiation to improve productsor services. The Nuclear RegulatoryCommission (NRC) and the 32 states thatparticipate in the NRC Agreement Statesprogram issue and administer more than20,000 licenses for medical, academic, andindustrial uses of nuclear materials.

Manmade radioisotopes are used by industryto:

• Explore for oil and natural gas.Geologists use a technique called nuclearwell logging to determine whether a welldrilled deep in the ground has the poten-tial to produce oil. Radiation from aradioisotope inside the well can detectthe presence of different materials.

• Test pipes and welds, including structuralcracks and stresses in aircraft (Figure 15)and test for flaws in jet engines. Using aprocess called radiography, the objecttested is exposed to radiation from asealed radiation source and a piece ofphotographic or radiographic film on theopposite side of the object captures animage which can help to pinpoint flawssuch as cracks or breaks.

• Control the thickness of sheet products,such as steel, aluminum foil, paper, pho-tographic film, and plastics, during manu-facture. Detectors measure, highly accu-rately, the amount of radiation passingthrough the materials and compare it tothe amount that should pass through thedesired thickness.

What Arethe

Benefitsand Risks


Industry

Figure 15. Airplane

3


28

• Cold-sterilize plastics, pharmaceuticals,cosmetics, and other heat-sensitiveproducts. Exposing the materials to radia-tion, usually gamma radiation fromCobalt-60, kills bacteria and germs and isparticularly effective when other methodssuch as boiling or chemical treatment arenot practical.

• Conduct security checks of airline carry-on luggage.

• Improve the quality of manufacturedgoods in thousands of industrial plants byusing radiation in sensitive gauges andimaging devices (for example, ensuringthat beverage cans are correctly filledusing a process similar to that of measur-ing the thickness of sheet products).

• Pinpoint fluid leaks, monitor enginewear and corrosion, and measure theflow of materials through pipes, usingradioactive tracers similar to those used in medicine.

• Identify trace quantities of materials.Criminal investigators use radiation toidentify trace amounts of materials likeglass, tape, gunpowder, lead, and poisons.Called activation analysis, the procedureinvolves placing a sample of materials ina nuclear reactor and bombarding it withneutrons, which produces a “fingerprint”of the elements in the sample.

• Prove the authenticity of old paintings.Museums also use activation analysis todetect whether certain modern materialsare present and use other techniques withradioisotopes to spot forgeries.

• Detect pollution. Scientists use radioiso-topes to trace and identify the sources ofpollution, such as acid rain and green-house gases, in air, water, and soil.

Nuclear Power One-sixth of the world’s electricity, andnearly one-fifth of the electricity in theUnited States, comes from nuclear powerplants. (Figure 16) These plants use nuclearfission (neutrons splitting uranium atoms)to produce tremendous heat that generateselectricity. Americans get more of their

electricity from nuclear power than fromany other source except coal.

But nuclear power plants also have a num-ber of drawbacks. U.S. nuclear power plantsgenerate about 2,000 metric tons of high-level radioactive waste each year, causingsignificant disposal problems. (See NuclearReactor Waste, Chapter 4, page 52).

Environmental and antinuclear groupsoppose nuclear power because of concernsabout safety, the potential for nuclearweapons proliferation and terrorism, andbecause of the unresolved problem ofnuclear waste disposal. They argue thatrenewable energy sources such as solar andwind power are preferable to nuclear poweras long-term alternatives to fossil fuel ener-gy. (For more on the pros and cons ofnuclear power, see Balancing the Benefitsand Risks, Chapter 3, page 43.)

Some people consider nuclear power plantsmore environmentally friendly than coal oroil-burning plants. As a byproduct of com-bustion, fossil-fuel plants emit air pollutantssuch as nitrogen oxide, sulfur dioxide, andcarbon dioxide, a principal “greenhouse gas”believed to contribute to global warming.Because nuclear plants use fission instead ofcombustion, they produce no combustionbyproducts. Without nuclear power, U.S.


NuclearPower

Figure 16. Nuclear Power Plant

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29

carbon emissions from electric generationwould be about 30 percent higher.

Also, because they are so closely regulatedand monitored, nuclear power plants releaseless ionizing radioactivity (an average doseof 0.009 mrem per year) into the environ-ment than comparable coal-fired plants (anaverage dose of 0.03 mrem per year). Newlimits on fly-ash emissions from fossil-fuelplants, however, are helping to reduceradioactive emissions from these sources as well.

According to the Nuclear Energy Institute,the industry’s trade association, the annualeconomic impact of the nuclear powerindustry is $90 billion in total sales of goodsand services; 442,000 jobs; and $17.8 billionin federal, state, and local government taxrevenues. The Institute estimates thatnuclear power reduces U.S. reliance on for-eign sources of oil by nearly 100 millionbarrels a year, enhancing the nation’s ener-gy security, and cutting the U.S. tradedeficit by billions of dollars each year.

AgricultureRadiation has become an increasinglyimportant tool in agricultural research andpractice. Some uses and their benefits are:

• Radioisotopes as a research tool helpdevelop new strains of food crops that aremore nutritious, resist disease, and pro-duce higher yields.

For example, radiation has been used inproducing peanuts, tomatoes, onions, soy-beans, barley, and the “miracle” rice thathas boosted rice production in Asia.

• Radioisotope tracers in plant nutrients aidin reducing soil and water pollution byhelping researchers to learn how plantsabsorb fertilizer and how to calculate theoptimum amount and frequency of fertil-izer applications.

• Insect sterilization with radiation resultsin mating without offspring, thus limitinginsect population growth. This has elimi-nated screwworm infestation in thesoutheastern United States and Mexico,

and has helped control theMediterranean fruit fly in California.With fewer pests, food crop productivityincreases.

• Moisture monitoring with nuclear densitygauges can measure the moisture contentof soil, helping make the most efficientuse of limited water sources for successfulcrop production.

Food IrradiationIrradiation Process

One of the more controversial uses of radia-tion today is food irradiation. High doses ofradiation do not make food radioactive.Irradiation kills bacteria, insects, and para-sites, and retards spoilage in some foods.Irradiated foods are regularly eaten by astro-nauts on space missions, as well as by hospi-talized patients with weak immune systemswho need extra protection from microor-ganisms in food.

The irradiation process involves exposingfood to intense controlled amounts of ioniz-ing radiation—gamma rays from cobalt-60or cesium-137, X-rays, or electron beamsfrom particle accelerators. The process hasabout the same effect on food as canning,cooking, or freezing. It kills pests andextends shelf life, but also reduces the food’snutritional value somewhat by destroyingvitamins A, B1 (thiamin), C, and E. Noradiation remains in the food after treatment.

Exposing materials, including foods, to radi-ation from an irradiator is very differentfrom exposing them to radiation from areactor. The gamma radiation from cobalt-60 in an irradiator kills bacterial andgerms, but does not leave any radioactiveresidue or cause any of the exposed materi-als to become radioactive. The cobalt-60 inan irradiator is contained in stainless steelcapsules and does not commingle with thematerial being irradiated. On the otherhand, material exposed to neutrons from areactor or linear accelerator can becomeradioactive.

What Arethe

Benefitsand Risks


FoodIrradiation

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30

Approvals and Bans

Irradiation has been approved by:

• The FDA - for a number of foods includ-ing, herbs and spices, fresh fruits and veg-etables, wheat, flour, pork, poultry, andred meat

• The World Health Organization

• The United Nations Food andAgricultural Organization

• Approximately 40 countries besides theUnited States

Three states—Maine, New Jersey, and NewYork—have banned the sale, however, ofirradiated foods and food ingredients(except for spices). Many U.S. food produc-ers have been reluctant to adopt food irradi-ation because of protests by food-safetygroups and because of uncertainties aboutconsumer acceptance.

Benefits

Irradiation advocates, including the FDAand the U.S. Department of Agriculture(USDA), point to a number of benefits offood irradiation:

• The process is better for the environmentthan treating foods with toxic chemicals,such as methyl bromide or ethyleneoxide.

• Irradiation, coupled with proper handling,cooking, and storage of food, can helpreduce the incidence of food-borne dis-ease. Some six million cases a year in theUnited States result in more than 9,000deaths.

• By retarding spoilage and extending theshelf life of food, irradiation also helpshumanitarian groups deliver food tostarving people.

Concerns

However, critics point to a number of con-cerns with food irradiation:

• Irradiated foods could pose a botulismhazard because the process kills bacteriathat cause spoiled food to smell or lookbad, thereby eliminating the traditionalsignals of inedible food.

• Irradiation can accelerate spoilage in sev-eral fruits, including pears, apples, citrusfruits, and pineapples.

• The irradiation process may expose work-ers and the environment to radiation hazards.

• Irradiation reduces the food’s nutritionalvalue by destroying some vitamins.

While extensive studies have found no evi-dence that irradiated foods or compoundscause adverse health effects, some con-sumers may find them unacceptable becausethey prefer natural or organic foods.

How do you know if the food in yourgrocery store has been irradiated?

The FDA requires irradiated foods to belabeled with the green radiation logo, calledthe radura (Figure 17) and the words “treat-ed by irradiation,” “treated with irradia-tion,” or “irradiated.”

However, processed foods containing irradi-ated ingredients and irradiated food sold inrestaurants do not have to be labeled.Consumer groups are working to expand thelabeling requirement.

Should you avoid irradiated food?

If your only concern is possible adversehealth effects, the government says no.

• The FDA has found no evidence thatirradiation of food is less safe than otherpreservation methods.

• Irradiation does a good job of killing bacteria that cause food-borne diseasessuch as, salmonella in poultry andseafood, E. coli in beef, trichinosis inpork, and cholera in fish.


FoodIrradiation

Figure 17.Radura label required on irradiated food

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Only a small fraction of our total annualexposure to radiation, about 11 millirem ayear, comes from consumer products.

The Space ProgramThe U.S. Space program has used radioiso-tope thermoelectric generators (RTGs) topower 24 of its space probes over the last 25years. The natural decay of plutonium diox-ide produces heat, which is converted toelectricity by a thermocouple device.Compact and relatively light, RTGs typical-ly produce about 300 watts of electricityand can operate unattended for years.

Among the space research probes powered-by RTGs were:

• The Apollo Lunar Surface ExperimentPackages (1969–1971)

• Pioneer 10 and 11 (1972 and 1973)

• Two Viking Mars spacecraft (1978)

• Two Voyager spacecraft (1977)

• The Galileo (1989), Ulysses (1990), andCassini (1997) spacecraft.

Sea PowerThe U.S. Navy was an early user of nuclearpower, launching the USS NAUTILUS, thefirst nuclear-powered submarine, in 1954.Since 1954, the Navy has built more than200 submarines and surface ships poweredby nuclear reactors. These vessels have trav-eled more than 100 million miles of oceanon nuclear power.

Nuclear submarines have two major advan-tages: speed and underwater range withoutsurfacing. A modern nuclear powered Navysubmarine can cruise up to one millionmiles, or more than 25 years, without refueling.

ResearchRadioactive materials are valuable tools forresearch in nearly all fields of modern sci-ence: physics, mineralogy, metallurgy, biolo-gy, medicine, agriculture, environmentalscience, geology, chemistry, and many others.

• Many scientists use X-rays and neutrons

But if it is more important to you that yourfoods are grown and packaged naturallywithout artificial treatments and with theirvitamins and minerals intact, then irradiat-ed foods may not be prime candidates foryour shopping list.

Consumer ProductsRadiation is used in, or to produce manyconsumer products. For example, manysmoke detectors—now installed in nearly90 percent of American homes—use theradioactive isotope americium-241, whichemits alpha radiation. By ionizing the airsealed inside the detector, the radiation pro-duces an electric current that sets off thealarm if interrupted by smoke in the detec-tor.

Radioactive materials are also used to:

• Eliminate dust from computer disks andaudio and video tapes

• Sterilize baby powder, bandages, cosmet-ics, hair products, and contact lens solu-tions (Exposing these materials to radia-tion, usually gamma radiation fromcobalt-60 kills bacteria and germs.)

• Control the thickness of many sheetproducts, such as paper, sandpaper, or alu-minum foil and the amount of liquid inbeverage can (Detectors measure, highlyaccurately, the amount of radiation pass-ing through the materials and compare itto the amount that should pass throughthe desired thickness.)

• Attach a non-stick surface to a frying pan

• Brighten the porcelain in false teeth tomake them look more real

None of the radiation remains in these con-sumer products after they are treated or sterilized.

Radioactive materials also create the glowin luminous watches and in instrumentpanel dials and are used in some gas camp-ing lanterns. Radiation is also used in pro-duction of some clothing, eyeglass lenses,lightning rods, tires, ceramic glazes on somechina and decorative glassware, enameledjewelry, and cellophane dispensers.

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to study the properties of a wide variety ofmaterials, develop new plastics, andstrengthen materials, such as those usedin aircraft.

• Chemists and biologists use X-ray diffractiontechniques to study the crystalline struc-ture of proteins, the basic building blocksof life, and also to study viruses that causediseases ranging from the common cold toAIDS.

• Environmental scientists use radioisotopes totrack chemical contaminants as theymove through water or the ground and tostudy the global movement of wind andwater.

• Geologists read radioactive materials thatoccur naturally in the earth to determinethe age of rocks and to study plate tectonics.

• Archaeologists determine the age of prehis-toric artifacts through carbon dating, aprocess that measures radioactive carbon-14. When an organism is alive, itsratio of carbon-14 to carbon-12 is thesame as in the atmosphere. When theorganism dies, the carbon-14 begins todecay and the ratio changes. This ratio isused to determine how long ago theorganism died.

• Criminologists use neutron activation analy-sis to detect the presence of toxic sub-stances such as arsenic in the body.

• Investigators detect forgeries by measuringradioactive decay; and use “ultrasoft” X-raysto determine the authenticity of paintingsand to aid in their restoration.

The Risks of Ionizing RadiationIonizing radiation is intricately woven intothe fabric of modern life. But living andworking with radiation can be hazardous. Ifwe want to continue enjoying the benefitsthat radiation brings, we may have toaccept some additional risk to our healthand environment.

How much risk is acceptable to us as a soci-ety? This is a subject of constant and oftenheated debate. To participate constructively

in that debate, we must:

• Understand the risks—how and to whatextent the different kinds and sources ofradiation can affect our health and envi-ronment.

• Learn what the producers and users ofradiation, the government, and each of usas individuals, can do to minimize thoserisks.

Measuring Human ExposureSeveral factors are involved in determiningthe potential health effects of exposure toradiation. These include:

• The size of the dose (amount of energydeposited in the body)

• The ability of the radiation to harmhuman tissue (See Ionizing Radiation,Chapter 1, page 12.)

• Which organs are affected

Amount of the Dose. The most importantfactor is the amount of the dose—theamount of energy actually deposited in yourbody. The more energy absorbed by cells,the greater the biological damage. Healthphysicists refer to the amount of energyabsorbed by the body as the radiation dose.The absorbed dose, the amount of energyabsorbed per gram of body tissue, is usuallymeasured in units called rads.

The amount of the dose depends on suchfactors as:

• The number and energy level of the radi-ation particles emitted by the source (thesource’s activity, measured in units calledcuries)

• The distance from the source (Distance isespecially important with alpha radiation;more than a few centimeters from thesource, the amount of the dose approach-es zero.)

• The amount of exposure time

• The degree to which radiation dissipatesin the air or in other substances betweenthe source and the recipient

• The penetrating power of the radiation


MeasuringHumanExposure

Everywhere! Los Alamos Science, LosAlamos National Laboratory, Number 23,1995.)

Studying Radiation’s Effects onHumansThere are a number of studies of the effectsof radiation on humans:

• The Radiation Effects ResearchFoundation (RERF) has been studyingthe long-term effects of radiation on thesurvivors of the Hiroshima and Nagasakibombings in Japan since 1947. RERF isan international organization jointlyfunded by the Japanese Ministry ofHealth and Welfare, the U.S.Department of Energy (DOE), and theNational Cancer Institute (NCI), part ofNational Institutes of Health.

• RERF researchers learn more about theeffects of ionizing radiation by monitoringuranium miners and people who livednear the Nevada nuclear weapons testsites used from 1951 through 1963.

• NCI is studying the people most affectedby the 1987 Chernobyl nuclear powerplant accident in Ukraine, especially chil-dren who lived nearby and workers whocleaned up the plant after the accident.

After rigorous peer review, the informationfrom the studies is published in medical andscientific journals and made available to thepublic. Because of these and other studies,more is known about the health effects ofionizing radiation than of any other car-cinogen.

Human Health Effects ofIonizing Radiation Ionization

Most atoms are electrically neutral; theyhave the same number of positively chargedprotons in their nucleus as negativelycharged electrons orbiting the nucleus.However, when ionizing radiation passesthrough a material, it can transfer some ofits energy to an electron; this “knocks” theelectron out of its orbit. The free negative

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Ability to Harm Tissue. Health physicistsalso must take into account the ability ofthe type of radiation involved to harmhuman tissue. To do this, they multiply theabsorbed dose by a biological effectivenessfactor, the Q factor, to come up with ameasurement of harm called the dose-equiv-alent. (Table 2) The Q factor is a “consen-sus factor” agreed upon by experts and usedfor regulatory purposes.

Table 2:Biological Effectiveness

Factor by Radiation Type

Type of Radiation Q Factor

Alpha particles 20

Beta particles 1

Gamma radiation 1

Protons, fast neutrons 10

Slow (thermal) neutrons 2

In the United States, dose-equivalent iscommonly expressed in rem, which standsfor radiation equivalent man. Small dosesare measured in thousandths of a rem ormillirem. The United States and interna-tional scientific communities also use unitscalled Sieverts, which are each equal to 100rem.

Which Organs are Affected. The potentialhealth effects of radiation also depend onwhich organs of the body are most likely toabsorb radiation.

• When ingested, radiation from somesources tends to accumulate in certainorgans. For example, iodine-131 concen-trates in the thyroid gland, where its betaradiation, at high doses, can be effectivein destroying hyperactive thyroid cells.

• Radiation from other sources is distrib-uted more widely in the body. For example, water containing tritium (aradioactive isotope of hydrogen) distrib-utes beta-emitting radioactivity through-out the body.

(Adapted from Ionizing Radiation—It’s

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electron leaves behind a positively chargedion (see Figure 18). This process is calledionization.

Knowing about ioniza-tion is important fortwo reasons.

• First, ions formed inliving tissue, such asthe human body, cancause both short-term and long-termdamage.

• Second, because ionshave an electricalcharge, they are easy to detect. Thismakes it possible to measure the amountof radiation present—even at extremelylow levels.

Exposure to Ionizing Radiation

Exposure to high levels of ionizing radiationis dangerous, even deadly. Acute exposureto radiation in the range of 300,000 to500,000 millirems can destroy cell tissuealmost immediately, causing death within afew days or weeks for more than half of theexposed population. Fortunately, the chanceof the average citizen receiving such a largedose of radiation is extremely small.

Doses above 5,000 millirem are known tosubstantially increase the risk of infectionand cancer and potentially cause geneticdamage to the exposed person and his orher offspring, Cataracts, premature aging,hair loss, skin burns, and a shortened lifespan are other known consequences ofhigh-level exposure. Since a radiation-induced cancer cannot be distinguishedfrom cancer caused by other factors,however, it is difficult to single out ra-diation as the cause of any particular cancer.

The average person in the United Statesreceives an exposure of approximately 360millirems per year. While exposure above5,000 millirem can cause observable biolog-ical effects (and at higher doses can befatal), there is little evidence of health orsafety effects at exposure levels below 1,000

millirem. Any exposure to radiation, how-ever, may pose some risk.

Many scientific studies have demonstrated arelationship between the amount of radia-tion and the likelihood of adverse healtheffects. To minimize human health effects,regulators assume that there is some riskassociated with any level of radiation, andset exposure standards accordingly.

High-Dose Effects

In the first decades after the discovery ofradioactivity and X-rays in the 1890s, thehealth effects of ionizing radiation were notrecognized. Scientists and others whoworked with radioactive materials took nospecial precautions to protect themselves.

Skin cancers in scientists who were studyingradioactivity were first reported in 1902. By1912, researchers found leukemia inhumans and animals exposed to radiation,and by 1930 genetic effects were identified.

In the 1930s, the occupational hazards ofworking with radiation became apparent. A1931 report described cases of bone cancerin women who licked the brushes (to get abetter brush point) they used to paintradioactive radium on watch dials. In 1944,the first cases of leukemia were reported inphysicians and radiologists who used radia-tion in their work. By 1951, thyroid cancerwas reported in persons exposed to radiationas children.



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Figure 18.Ionization of an atom


nucleus electron

NeutrallyChargedAtom

TransitionalStage

Ion

free electron

radiation

radiation

3

In 1945, Japanese citizens were exposed tohigh doses of radiation (up to 500,000 mil-lirem or more) during the bombings ofHiroshima and Nagasaki. (Figure 19)Studies of the atomic bomb survivors andother people exposed to high levels of radia-tion have shown that acute exposure to ion-izing radiation can cause cancer, sterility,and genetic damage; and damage to bonemarrow, the central nervous system, and thegastrointestinal system.

In the years since the bombing onHiroshima and Nagasaki, scientists havetracked the health histories of more than75,000 survivors. (See Studying Radiation’sEffects on Humans, page 33.) The studiesindicate that radiation was a factor inapproximately 12 percent of all the cancers(including leukemia, breast cancer, thyroidcancer, and skin cancer), and approximately9 percent of the 6,000 fatal cancers thatdeveloped among the atomic bomb sur-vivors. In sum, this means approximately500 more cancer deaths occurred among theexposed population than an unexposed pop-ulation of the same size.

Other effects that appeared in the exposedpopulation include the suppression of theimmune system and cataracts. An increasedrate of mental retardation has been found inatomic bomb survivors whose mothers werebetween 8 and 25 weeks pregnant at thetime of exposure. (The brain tissues of afetus are especially sensitive to radiation atcertain stages of development.) So far, how-ever, the children and grandchildren ofexposed survivors have shown no greaterincidence of genetic problems than unex-posed populations. More than 56 percent ofthe exposed survivors were still alive in1990, when the most recent cycle of mor-tality information was completed.

These studies have made it possible for sci-entists to record the long-term effects of awide range of radiation doses, includingdoses comparable to an average person’slifetime dose from naturally occurring back-ground radiation, about 20,000 millirem(300 millirem a year for 70 years).

Among the most important findings fromthe human health studies are:

• The larger the radiation dose a personreceives, the greater the risk of develop-ing cancer.

• The chance of cancer occurring (but notthe kind or severity of cancer) increasesas the dose increases.

• Most cancers do not appear until manyyears after exposure (typically 10 to 40years).

Low-Dose Effects

Determining the health effects of exposureto low levels of radiation has been muchmore difficult than determining the effectsof high-level exposure, for two reasons.

• Cells can repair some damage caused bylow levels of radiation absorbed over longperiods of time.

• It is difficult to tell whether a particularcancer was caused by radiation, by one ofthe more than 300 other known carcino-gens in the environment, or by otherunknown factors.

Dr. Arthur C. Upton, former chairman ofthe New York University Medical Center,Department of Environmental Medicine,

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Figure 19.Atomic bomb explosion


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has compared efforts to detect the effects oflow-level radiation with “trying to listen toone violin when the whole orchestra isplaying. You can’t hear it.”

The numerous studies of potential healtheffects in people exposed to low-level radia-tion (that is, below about 10,000 to 40,000millirem) have yielded inconclusive results.For example, studies have been conductedin populations living with background radi-ation several times higher than the UnitedStates. These studies have not found anystatistically significant evidence of a corre-lation between cancer mortality and levelsof background radiation.

Many scientists and policy makers take theposition that any amount of radiation expo-sure, even at background levels, poses someincreased risk of adverse health effects. Justhow much risk, however, is still unknownand is the subject of continuing debate.

Although no health effects have beenobserved at very low doses, regulatorsassume that any amount of radiation maypose an increased risk for causing cancerand hereditary effects. They also assumethat there is a one-to-one, or linear rela-tionship between a radiation dose and itseffect. That is, small doses have a small riskin direct proportion to the known effects oflarge doses.

This technique, known as the linear no-threshold hypothesis, uses mathematical mod-els to estimate the risks of very low expo-sures based on the known risks of high-levelexposures. Some scientists question the lin-ear hypothesis because of the lack of evi-dence of health effects from low radiationdoses, as well as the fact that many otherhazardous substances harmful at high doseshave little or no effect at low doses. TheU.S. Committee on the Biological Effects ofIonizing Radiation (BEIR), convened bythe National Academy of Sciences (NAS),acknowledged in 1990, that there is no datashowing that low doses of radiation causecancer.

The BEIR Committee, however, recom-mended the use of the linear no-threshold

hypothesis because it is consistent withother approaches to public health policy.The United States and other countries uselinear estimates to set limits on all potentialexposures to radiation, both for the publicand for workers in jobs that expose them toionizing radiation. (See National Academyof Sciences, Chapter 5, page 67.)

In 1998, the BEIR Committee reported thatrecent epidemiological studies of radiationand cancer warrant a reevaluation of thehealth risks associated with low-level dosesof radiation. The committee will review allrelevant data and develop new risk modelsto try to determine more definitively thehealth risks, if any, from low-level doses ofradiation.

Lifetime Risk of Cancer fromIncreased Radiation Exposure

The BEIR Committee estimated the life-time risk of cancer to individuals from high-level and low-level exposures to radiation.(Table 3) These estimates used the linear no-threshold hypothesis to developaverage cancer estimates over all possibleages at which a person might be exposed,weighted by population and age distribu-tion. The calculation compares the esti-mated increase in cancers due to whole-body external radiation from a single, high-level exposure (10,000 millirem), and fromcontinuous low-level exposure (500 mil-lirem, the current upper limit for individualexposure recommended by federal guidance).

Because of the extensive scientific researchon radiation and the large number of studiesof exposed persons, these estimates have ahigher degree of certainty than the risk esti-mates for most chemical carcinogens.

Genetic Effects

Both high-level and low-level radiation maycause other adverse health effects besidescancer, including genetic defects in thechildren of exposed parents or mental retar-dation in the children of mothers exposedduring pregnancy. The risk of genetic effectsdue to radiation exposure, however, is much



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lower than the risk of developing cancer.

By breaking the electron bonds that holdmolecules together, radiation can damagehuman DNA, the inherited compound thatcontrols the structure and function of cells.Radiation may damage DNA directly bydisplacing electrons from the DNA mole-cule, or indirectly by changing the structureof other molecules in the cell, which maythen interact with the DNA. When thishappens, a cell can be destroyed quickly orits growth or function may be alteredthrough a change (mutation) that may notbe evident for many years. (Figure 20) Atlow radiation doses, however, the possibilityof such a change causing a clinically signifi-cant illness or other problem is believed tobe remote.

In addition, cells have the ability to repairthe damage done to DNA by radiation,chemicals, or physical trauma. How wellcellular repair mechanisms work depends onthe kind of cell, the type and dose of radia-tion, the individual and other biological factors.

Health Effects of RadonRadon accounts for more than half of ourtotal average annual exposure to radiation,about 200 millirem per year. (Figure 21)Radon is a known cause of lung cancer in humans. The most recent NationalAcademy of Science (NAS) report onradon, The Health Effects of Exposure toRadon (the BEIR VI Report, published in1999), stated that radon is the second lead-ing cause of lung cancer and a serious publichealth problem. The NAS report estimatedthat about 12 percent of lung cancer deathsin the United States are attributable toexposure to radon in indoor air—about15,000 to 22,000 lung cancer deaths eachyear. In a second NAS report published in1999 on radon in drinking water, the NASestimated that about 89 percent of the fatalcancers caused by radon in drinking waterwere due to lung cancer from inhalation ofradon released to indoor air, and about 11percent were due to stomach cancer fromconsuming water containing radon.

Radon decay products can attach them-selves to tiny dust particles in indoor air,which are easily inhaled into the lungs. Theparticles then attach to the cells lining thelungs and emit a type of ionizing radiationcalled alpha radiation. This can damagecells in the lungs, leading to lung cancer.Our knowledge of the health effects ofradon comes from extensive studies of min-ers and of people exposed to radon in theirhomes. Experimental studies in animals and


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37Source: U.S. Environmental Protection Agency

Figure 20. Genetic damage from radiation

1. When radiation penetrates a human cell, it may damage molecules in its path.

2. If a DNA molecule is damaged, the chromsome containing that DNA molecule may break apart.

3. The chromosome may then recombine abnormally. This change in chromosomestructure may lead to the death of the cell or the formation of a cancerous cell.

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molecular and cellular studies provide sup-porting evidence and some understanding ofthe mechanisms by which radon (i.e., alpharadiation) causes lung cancer.

A person’s risk of getting lung cancer fromradon depends upon several variables,including the level of radon in the home,the amount of time spent in the home, andwhether the person is a smoker. The risk oflung cancer is especially high for cigarettesmokers exposed to elevated levels of indoorradon. NAS found evidence of an interac-tion between radon and cigarette smokingthat increases the lung cancer risk to smok-ers beyond what would be expected fromthe additive effects of smoking and radon.In most cases, radon in soil under homes isthe biggest source of exposure to radon.However, there are public health concernsassociated with drinking water containingradon. When radon in water is ingested, it is distributed throughout the body. Some ofit will decay and emit radiation while in the

body, increasing the risk of cancer in irradi-ated organs (although this increased risk issignificantly less than the risk from inhalingradon).

Most of the damage is not from radon gasitself, which is removed from the lungs byexhalation, but from radon’s short-liveddecay products (half-life measured in min-utes or less). When inhaled, these decayproducts may be deposited in the airways ofthe lungs and subsequently emit alpha parti-cles as they decay further. The increasedrisk of lung cancer from radon primarilyresults from alpha particles irradiating lungtissues. When an alpha particle passesthrough a cell nucleus, DNA is likely to bedamaged, and available data indicate that asingle alpha particle passing through anucleus can cause genomic changes in acell, including mutation and transforma-tion. Since alpha particles are more massiveand more highly charged than other types



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Source: U.S.Environmental ProtectionAgency (radiation esti-mates) and National Centerfor Health Statistics (1997data).

Source: National Academy of Sciences

Table 3: Estimated Lifetime Cancer Risk from Increased Radiation Exposure

Type of exposure to whole-body external radiation

Single, high-level exposure to 10,000 millirem

Continuous low-level exposure to 500 millirem

Increase in cancers per 1,000 people(above that expected for a similar butunexposed population)

8 cancers (about 3%)

5.6 cancers (about 2%)

HIV and AIDS 17,000

Kidney diseases 25,000

Natural Radiation* 35,000

Diabetes 62,000

Stroke 160,000

Cancer 537,000

200,000 400,000 600,0000

*An estimated 20,000 from radon and 15,000 from natural sources other than radon.

Figure 21.Annual deaths fromnatural radiation andselected other causes.

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of ionizing radiation, they are more damag-ing to the living tissue.

An important finding of the BEIR VI reportis that even very small exposures to radoncan result in lung cancer. The NAS con-cluded that no evidence currently existsthat shows a threshold of exposure belowwhich radon levels are harmless, that is, alevel below which it is certain that noincreased risk of lung cancer would exist.

Radiation-Related HealthEffects from Living nearNuclear Power PlantsNuclear power plants expose people livingnear them to small amounts of radiation,less than one millirem per year. (Figure 22)In the United States, the EPA sets strictstandards governing radiation emissions,which are enforced by the NuclearRegulatory Commission. Radiation levels atnuclear power plants are monitored24–hours–a day. Neighboring soil, cows’milk, fish, and sediment in rivers and lakesare monitored periodically.

In September 1990, a National CancerInstitute study found no evidence of anincrease in cancer mortality among peopleliving in 107 counties that host or are adja-cent to 62 nuclear facilities in the UnitedStates. The research, which evaluated mor-tality from 16 types of cancer, showed noincrease in childhood leukemia mortalityrates in the study counties after nuclearfacilities were opened. The NCI surveyed900,000 cancer deaths in counties nearnuclear facilities that operated for at leastfive years prior to the start of the study (theminimum time considered sufficient forrelated health effects to appear).

The conclusions of the NCI study, thebroadest ever conducted, are supported bymany other scientific studies in the UnitedStates, Canada, and Europe.

Accidental ReleasesMany people worry about the risks of radia-tion not so much because of routine, low-level exposures, but because of the possibili-ty of an accident at the plant. What if anexplosion or meltdown at a nuclear reactorreleased deadly amounts of radiation orradioactive materials into the environment?Public anxiety was heightened in March1979 by the accident at the Three MileIsland nuclear power plant in Pennsylvania.That accident was followed by a muchworse catastrophe at the Chernobyl nuclearpower plant in the former Soviet Union inApril 1986.

Three Mile Island

Three Mile Island is the only major acci-dent in the history of U.S. commercialnuclear energy. Although some radioactivematerial escaped from the reactor contain-ment building, the accident caused nodeaths or injuries. It resulted in an averagedose of eight millirems to people livingwithin 10 miles of the plant (about thesame as a chest X-ray) and only 1.5 mil-lirem to people living within a 50-mileradius. The maximum individual dose wasless than 100 millirem. Subsequent studieshave found no evidence of increases in can-cer (including childhood leukemia), thyroiddiseases, or other health effects as a result ofthe accident.


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Figure 22.Nuclear power plant

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Chernobyl

The Chernobyl accident, however, wasmuch more serious than Three Mile Island.There was no containment building aroundthe reactor. A chemical explosion set thereactor core on fire, directly releasing largeamounts of radioactivity into the atmos-phere. Thirty-one plant workers and fire-fighters, who received doses up to 1.6 mil-lion millirem, died from the accident, andmore than 130 plant workers and rescuerssuffered from confirmed cases of acute radia-tion sickness. The average radiation dose tothe 135,000 people evacuated from theregion was 12,000 millirem. The dosesincluded external gamma radiation, betaradiation to the skin, and internal doses tothe thyroid.

During the first year after the accident,excess radiation doses to adults in sevenWestern European countries ranged from130 millirem in Switzerland, to 95 milliremin Poland, to 2 millirem in southernEngland. Nearly 3 million acres of farmlandin Ukraine were contaminated by radioiso-topes and plutonium, and may be unusablefor decades. Chernobyl was a graphic exam-ple of just how serious the health and envi-ronmental consequences of a catastrophicnuclear accident can be.

Could such an accident happen again?While there are still some Chernobyl-typereactors operating in Eastern Europe thatare cause for concern, remedial measureswere taken to enhance the safety of thesereactors. Safety upgrades, performedbetween 1987 and 1991, essentially reme-died the design deficiencies that con-tributed to the accident.

Reactor Safety Standards

Most of the world’s nuclear power plants arebuilt differently than Chernobyl and oper-ate according to much stricter safety stan-dards. They have redundant safety systemsto prevent the kind of explosion and firethat released radioactive material into theenvironment at Chernobyl. National andinternational nuclear regulatory bodies keepa watchful eye on reactor operations and

target potentially unsafe conditions andpractices. If companies do not take promptaction to correct such safety problems, theycan be forced to shut down their reactors.

As new reactors replace older reactors, thenew designs will include safety features suchas the use of gravity and convection incooling water systems rather than mechani-cal pumps and motors that might fail. Newcontrol room designs will also reduce thepossibility of human error, a significant fac-tor in both the Three Mile Island andChernobyl accidents. The Nuclear EnergyInstitute, an industry group, argues that theadvanced plants will be able to meet safetygoals that are more than 100 times morestringent than those of current nuclearplants.

The haunting specters of Chernobyl and, toa lesser extent, Three Mile Island, willlinger in the public’s memory for years tocome. But there are other issues related tonuclear power, particularly the managementand disposal of highly radioactive waste thatpose potential risks to public safety and theenvironment. These issues are discussed inChapter 4.

Determining Your ExposureMost of the exposure levels described in thisguidebook are averages and may not reflectyour own individual exposure or that ofmembers of your family. Depending onwhere you live, your lifestyle, and youroccupation, you could be exposed to moreor less radiation than the average person.

For example, if you live in “mile-high”Denver, Colorado, your average annual dosefrom cosmic radiation is about 50 milliremper year. If you live in Leadville, Colorado,at an altitude of two miles, your cosmicradiation dose is closer to 125 millirem peryear. However, if you live on a coastal plain,like Florida, you receive only about 26 mil-lirem per year from cosmic radiation.

Some parts of the country have higher con-centrations of radon and radioactive miner-als in the soil than others. In Ohio, forexample, a line of Ohio Black Shale runs


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through the center of the state from southto north, along part of the Lake Erie shore,and in the northwestern parts of the state.Many people who live over this shale expe-rience higher doses from radon than thosewho live elsewhere in Ohio. Also, veryhigh levels (hundreds or even thousands ofpCi/L ) of radon have been found in homesbuilt in the area known as the Reading Prong in the Northeastern United States.(See Radon, Chapter 2, page 18 and TheHealth Effects of Radon, Chapter 3, page37.)

Other factors that help determine yourexposure include:

• The consumer products you use regularly

• The number of medical and dental proce-dures using radiation that you undergoannually

• The kind of work you do. (Airline flightcrews receive many times the averageradiation exposure from cosmic rays whilein the air, an extra 100 millirem per yearon average.)

• Whether you smoke

• The kind of house you live in

You can use Table 4 to do a rough calcula-tion of your annual exposure to radiation.

Determining Levels of RiskTo establish standards for protecting thepublic from environmental hazards, includ-ing radiation, regulators often use a type ofanalysis called risk assessment. RiskAssessment includes four steps:

1. Hazard identification. In this step,researchers determine whether a sub-stance causes cancer or other healtheffects. Human data has confirmed thationizing radiation can cause cancer in thehuman body. Factors to determining thehazard associated with exposure to partic-ular radiation include the following:

• Amount of radioactivity

• Type of radiation involved

• Duration of exposure

• Distance from the source

• Other factors that contribute to the risk of harm resulting from exposure to radiation include:

• Types of cells and specific parts of thebody that absorb the radiation

• The exposed person’s age, sex, physicalcondition, and genetic tendency either toresist or be affected by radiation

(See Measuring Human Exposure in thisChapter, page 32.)

2. Dose-response assessment. This stepdetermines the relationship between theamount of exposure and the likelihood ofdeveloping cancer and other healtheffects. The accuracy of this assessment isbased on the quality of information avail-able from similar exposures. The data onradiation dose-response relationships arevery reliable at high doses. Scientistsextrapolate the known dose-response rela-tionship to estimate risk at low levels ofexposure. This method is considered bymany to be reasonably conservative, buthas its critics who consider it either tooliberal or too conservative.

3. Exposure assessment. This step involvesestimating the extent to which peoplecould be exposed to radiation emitted bythe source. It includes estimating:

• How much of the source exists,

• How radiation from the source will reachpeople (e.g., through the air, water, orfood), and

• How big a dose they will receive fromeach medium the radioactive materialtravels through (e.g., How much contam-inated air will they breathe? How muchcontaminated water will they drink?).

4. Risk characterization. This step com-bines the results of the previous steps tosummarize the risk potential of the haz-ard, and describe the strengths and weak-nesses of the risk assessment.

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Your AverageSource Annual Dose (mrem)

Cosmic radiation at sea level (from outer space) 26

What is the elevation (in feet) of your town?

up to 1000, add 2 mrem 5,000 - 6,000, add 29 mrem1,000 - 2,000, add 5 mrem 6,000 - 7,000, add 40 mrem2,000 - 3,000, add 9 mrem 7,000 - 8,000, add 53 mrem 3,000 - 4,000, add 15 mrem above 8,000, add 70 mrem4,000 - 5,000 add 21 mrem

Terrestrial (from the ground): What region of the US do you live in?

Gulf Coast, add 16 mremAtlantic Coast, add 16 mremColorado Plateau, add 63 mremElsewhere in United States, add 30 mrem

Internal radiation (in your body): From food and water, (e.g. potassium and radon in water) 40

From air, (radon) 200

Do you wear a plutonium powered pacemaker? If yes, add 100 mrem

Do you have porcelain crowns or false teeth? If yes, add .07 mrem

Travel Related Sources: Add .5 mrem for each hour in the air

Are X-ray luggage inspection machines used at your airport? Yes, add .002 mrem

Do you use a gas camping lantern? If yes, add .2 mrem

Medical Sources

X-rays: Extremity (arm, hand, foot, or leg) add 1 mrem Dental X-rays, add 1 mremChest X-rays, add 6 mrem Pelvis hip, add 65 mremSkull/neck, add 20 mrem Barium enema, add 405 mremUpper GI, add 245 mrem

CAT Scan (head and body), add 110 mremNuclear Medicine (e.g. thyroid scan), add 14 mrem

Miscellaneous Sources: Weapons test fallout 1

Do you live in a stone, adobe brick, or concrete building? If yes, add 7 mrem

Do you wear a luminous wristwatch (LCD)? If yes, add.06 mrem

Do you watch TV? If yes, add 1 mrem

Do you use a computer terminal? If yes, add .1 mrem

Do you have a smoke detector in your home? If yes, add .008 mrem

Do you live within 50 miles of a nuclear power plant? If yes, add .01 mrem

Do you live within 50 miles of a coal fired power plant? If yes, add .03 mrem

TOTAL YEARLY DOSE (in mrem):

[Note: The amount of radiation exposure is usually expressed in a unit called millimrem (mrem). In the United States, theaverage person is exposed to an effective dose equivalent of approximately 360 mrem (whole-body exposure) per year from all

sources (NCRP Report No. 93).]

Source: U.S. EPA and American Nuclear Society based on Data from the National Council on Radiation Protection and MeasurementsReports # 92 - 95 and #100.

Table 4:What Is Your Estimated Annual Radiation Dose?

3


What Arethe

Benefitsand Risks


Balancing theBenefits and

Risks ofRadiation

43

Balancing the Benefits andRisks of RadiationGovernmental Risk Assessments andStandards

Because exposure to high-level ionizingradiation is known to cause cancer andother health problems, public health regula-tors have taken a cautious approach. Theyassume that any exposure could cause simi-lar effects. They have established protectivestandards by directly extrapolating the risksfrom high doses of radiation to minimizethe risks of exposure to low doses. Much ofthe current controversy surrounding radia-tion is based on whether we should assumelow doses also cause health affects.

Since most scientists assume that any radia-tion exposure entails some risk, how do wedecide what level of risk is justified by thebenefits of its use? In life, there is always astatistical chance that some people willcontract certain diseases. Scientists andpublic health professionals perform riskassessments to determine the additionallikelihood of being harmed from exposureor from certain behaviors. For a carcinogensuch as radiation, risk is the additional like-lihood of contracting cancer from exposure.

Over the years since radiation was first dis-covered and used, the government has con-stantly tightened the standards that limitthe amount of radiation to which workersand the public can be exposed. The nation-al and international regulatory standards forradiation exposure are based on moreresearch and more direct evidence of healtheffects than for almost any other hazardoussubstance. By setting and enforcing strictexposure standards, governments have triedto balance the benefits of using radiationwith the risks.

Individual Judgments

Making judgments on safety for society as awhole is primarily the government’s respon-sibility (see Chapter 5). But each of us asindividuals can also avoid unnecessaryexposure to radiation, so that we derive thebenefits from radiation and do not undergo

more risk than necessary (also see Chapter 5).

It is always prudent to avoid unnecessaryexposure. However, refusing X-rays or radia-tion therapy may cost more money, time,convenience, or health problems, than tak-ing advantage of radiation’s unique diagnos-tic and healing properties. Each of us mustmake such decisions based on our tolerancefor risk, and our confidence in doctors andtheir medical advice.

Society’s Judgments, Pro and Con

Society as a whole must balance the risksand benefits associated with nuclear energy,including the use of radiation. Nuclearadvocates argue that nuclear power is aproven, secure, and inexhaustible long-termsource of energy. They argue that nuclearenergy creates little air pollution, and con-tributes almost nothing to global warming.

Nuclear energy could become increasinglyimportant in the twenty-first century asglobal energy demands continue to rise, andnonrenewable energy sources, such as fossilfuels and natural gas, are slowly depleted.Proponents say that nuclear power, if prop-erly managed, can benefit humanity and theenvironment with a level of risk no greaterthan that we routinely accept as part of ournormal lives.

Critics of nuclear power, however, rangingfrom environmentalists to antiwar activists,point to a variety of problems with nuclearenergy, including:

• The dangers inherent in transporting anddisposing of the thousands of tons ofhigh-level radioactive waste, now in tem-porary storage at nuclear power plantsacross the nation. (See Nuclear ReactorWaste, Chapter 4, page 52.)

• The possibility that radioactive materialused by and generated in nuclear reactorscould be diverted by rogue nations (orterrorists) to produce nuclear weapons.

• The risk of a dangerous accident, particu-larly in aging reactors whose protectivesystems may have been weakened or

3



Balancing theBenefits andRisks ofRadiation

44

whose containment structures may beinadequate to prevent the release ofradioactivity into the environment.

• The siting of nuclear plants in denselypopulated areas, which increases the dan-ger that an accident or terrorist attackcould expose large numbers of people todangerous levels of radiation.

• The unique problems associated with dis-mantling and decommissioning nuclearfacilities, and cleaning up sites after theyare closed down.

Some opponents of nuclear energy arguethat the problems are so serious that weshould shut down the nuclear power indus-try. A better alternative, nuclear criticsclaim, would be to focus attention andresources on developing safe, nonpolluting,renewable energy sources such as solar,wind, and geothermal power.

Future Prospects for Nuclear PowerPartly because of these disagreements, thefuture of nuclear power is mixed. Evenadvocates acknowledge that few if any newnuclear power plants are likely to be built inthe United States in the next decade. Inpart, this is due to the lack of public sup-port. A March 1999 Associated Press poll,taken 20 years after Three Mile Island,showed that only 45 percent of Americanssupport the use of nuclear energy, 10 per-cent fewer than in 1989.

Recent energy supply problems inCalifornia, however, have sparked somerenewed interest in nuclear power. Anotherlimiting factor is the high cost of buildingnew nuclear plants. In addition, many ofthe existing plants now nearing the end oftheir useful lives are unlikely to be replaced,at least right away. Many will seek licensesto operate for a longer time period.

Government and industry experts continueto design safer reactors, work to improvetechniques for decontaminating older reac-

tors, and find safer, more secure ways tohandle and dispose of radioactive wastes.Some proponents expect nuclear energy tocontribute to a growing share of the world’sincreasing energy needs in spite of contin-ued protests and controversy.

4U N D E R S T A N D I N G R A D I A T I O N I N O U R W O R L D

45

Radiation offers many important benefits tosociety. However, every use of radioactivematerials—for mining, nuclear power, man-aging nuclear weapons, nuclear medicine,and scientific research—generates radioac-tive waste. The overall risk to the publicfrom radioactive waste is lower than fromother sources of radiation, such as radonand nuclear medicine. (See BalancingRadiation’s Benefits and Risks, Chapter 3,page 43).

Areas where nuclear waste is produced,transported, and stored pose potential risksto the environment and people living closeto them. Care must be taken to properlyisolate the waste materials from the publicand the environment.

Radioactive materials can:

• Travel through air and water (bothground water and surface water)

• Contaminate the air, soil, water supply,and food chain

• Enter the human body through the skinor when humans eat, drink, or inhale.

By responsibly managing the transportation,storage, and disposal of radioactive materi-als, users and regulators of radiation cangreatly reduce the risk to human health andthe environment.

This chapter covers these topics:

• Radioactive Waste Disposal

• The Search for Permanent Disposal Solutions

• Radioactive Waste Cleanup

• Transporting Radioactive Waste

Radioactive Waste DisposalMuch of the public anxiety and controversyabout nuclear energy and other uses ofradioactive materials concerns how radioac-tive waste is handled, transported, and dis-posed of. Some high-level waste will remainhazardous for 10,000 years or more, furthercomplicating the problem of ensuring safe,long-term disposal and raising questionsabout our responsibility to future genera-tions.

Several federal agencies and some statesthat regulate the risks of radioactive wasterequire disposal facilities to effectively isolate the waste. Examples:

• EPA has established environmental stan-dards for disposal of radioactive millingwastes.

• EPA sets generally applicable environ-mental standards for disposal of otherradioactive wastes.

• NRC and DOE have established specificregulations for different types of waste(e.g., low-level radioactive waste).

• The Department of Transportation(DOT) and the NRC have establishedstrict safety standards for vehicles andcontainers used to ship radioactive waste.(See Transporting Radioactive Waste inthis Chapter, page 55.)

How AreRadio-active

WastesManaged?

Radioactive Waste

Disposal

How Are Radioactive Wastes Managed?

4


46

Types of Radioactive Waste

Radioactive waste is divided into seven gen-eral categories:

1. Spent nuclear fuel and High-level wasteinclude commercial spent reactor fuel andother highly radioactive material whichrequire careful isolation and security.

2. Transuranic waste contains manmaderadioisotopes heavier than uranium. Thiswaste is produced primarily from defense-related activities, such as nuclear weaponsresearch, production, and cleanup. It gen-erally consists of radioactively contami-nated clothing, tools, glassware, equip-ment, soil, and sludge.

3. Low-level waste includes radioactivelycontaminated industrial or research wastesuch as paper, rags, plastic bags, packagingmaterials, protective clothing, organic flu-ids, and water-treatment resins. It is gen-erated by government facilities, nuclearpower plants, industries, and institutionalfacilities (e.g., universities and hospitals).More than 22,000 commercial users ofradioactive materials generate someamount of low-level waste.

4. Mill tailings are mining and millingresidues of uranium ore that contain lowconcentrations of naturally occurringradioactive materials.

5. Mixed waste is a combination of radioac-tive materials and hazardous chemicalwaste.

6. Orphaned sources are radioactive contami-nants that find their way into non-nuclear facilities such as scrap yards, steelmills, and municipal waste disposal facili-ties. The contamination usually comesfrom discarded highly radioactive materi-als inside metal containers which are mis-taken as scrap metals.

7. Naturally-occurring and accelerator-pro-duced radioactive materials (NARM)include:

• Radioactive waste products from the operation of atomic particle accelera-tors, and

• Naturally occurring radioactive materials(NORM), usually from mineral extrac-tion or processing activities, whose natu-ral radioactivity has been technologicallyenhanced (also referred to as “TENORM”materials).

Radioactive waste categories are based onthe origin of the waste, not necessarily onthe level of radioactivity. For example, somelow-level waste is highly radioactive.Radioactive wastes can remain hazardousfor a few days or for hundreds and eventhousands of years, depending on theirradioactive half-lives. (See IonizingRadiation, Chapter 1, page 12.)

Sites and Methods of WasteDisposal

Several major environmental laws affect theoperations of many facilities that generateradioactive waste, including DOE’s nuclearweapons facilities.

• The Resource Conservation andRecovery Act (RCRA), regulates thegeneration, treatment, storage, and dis-posal of municipal and industrial haz-ardous and solid waste.

—Facilities that generate hazardous ormixed hazardous and radioactive wastesmust obtain RCRA permits from EPAor authorized states to operate. Theymust also have RCRA permits to treat,store, or dispose of these wastes.

—The Hazardous and Solid Waste Amendments to RCRA (1984) requireDOE to eliminate contaminant releasesat or from its RCRA facilities.

• The Comprehensive EnvironmentalResponse, Compensation, and LiabilityAct (CERCLA, also known asSuperfund) and its 1986 amendmentsestablished hazardous and radioactivewaste cleanup requirements for contami-nated facilities, including those in theweapons complex. EPA has placed anumber of DOE’s contaminated weaponssites on the Superfund National PrioritiesList (NPL) for expedited evaluation andcleanup.

How AreRadio-activeWastesManaged?

Radioactive WasteDisposal

4


47

• The Atomic Energy Act as amendedestablished requirements for the manage-ment and disposal of radioactive wastethat is regulated by DOE, NRC and EPA.

High-Level Waste: Interim Storage

The United States currently has no perma-nent disposal facility for high-level radioac-tive waste. The NRC says that interim stor-age methods can be used safely for 100years. However, NRC, the nuclear utilityindustry, and many independent observersbelieve it is important to find a long-termsolution for nuclear waste disposal.Significant obstacles to reaching a solutioninclude scientific challenges and publicconcerns. (See The Search for PermanentDisposal Solutions in this Chapter, page49.)

As an interim storage method, nuclear reac-tor operators keep spent nuclear reactor fuelon site at nuclear power plants and otherreactor sites, usually in concrete, steel-linedpools of water (see Nuclear Reactor Wastein this Chapter, page 52.) The water coolsthe warm fuel and also provides shieldingfrom the radiation. Reactor operatinglicenses issued by NRC limit the amount ofspent fuel that can be kept on site.

Chemical reprocessing of spent fuel fromreactors in the U.S. defense program isanother type of high-level waste. Thisprocess, which has been suspended, recov-ered unused uranium and plutonium formaking nuclear weapons. U.S. policies pro-hibit the reprocessing of spent fuel fromcommercial nuclear reactors.

The liquid waste from reprocessing is beingtemporarily stored in underground tanks orstainless steel silos. These are located onfederal reservations in Washington, SouthCarolina, and Idaho, and at the NuclearFuel Services Plant in West Valley, NewYork. (See Nuclear Weapons Waste in thisChapter, page 51.) Scientists continue torefine techniques for treating this waste soit can be more easily and safely transportedand disposed of after a permanent disposalsite becomes available.

Transuranic Waste

Transuranic wastes are also temporarilystored in metal drums and shielded casks atthe sites where they are generated—prima-rily nuclear weapons facilities and nationallaboratories. Eventually they will be shippedto DOE’s permanent disposal facility, theWaste Isolation Pilot Plant (WIPP). TheWIPP, located near Carlsbad, New Mexico,cleared its last legal challenges and beganreceiving waste shipments in March 1999.

The WIPP, authorized by Congress in 1979,is the world’s first geological repository forthe permanent disposal of transuranicwastes and transuranic mixed wastes. (Figure 23)

How AreRadio-active

WastesManaged?

Radioactive Waste

Disposal

Figure 23.Aerial view of the WIPP


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48

In 1992, Congress passed the WIPP LandWithdrawal Act, which makes EPA respon-sible for ensuring that the WIPP complieswith the agency’s radioactive waste disposalstandards and other federal environmentallaws and regulations. The law requires thatEPA certify that the waste stored in theWIPP can be isolated from the human envi-ronment for at least 10,000 years. EPAissued this safety certification for the WIPPon May 13, 1998. The facility must berecertified by EPA every five years through-out its operational life.

As of the end of December 2000 the WIPPhad received 128 shipments of transuranicwaste from four DOE sites.

Low-Level Radioactive Waste

Most low-level radioactive wastes are solidi-fied, put into drums, and buried in 20-foot-deep trenches, which are backfilled andcovered in clay each day. When full, thetrenches are capped with clay and a foot ofgrassy topsoil.

Only a few commercial facilities that per-manently dispose of low-level radioactivewaste (Figure 24) are operating in theUnited States. The major facilities arelocated in:

• Richland, Washington, which acceptswaste only from 11 northwest and RockyMountain states.

• Barnwell, South Carolina, which is partof the newly formed Atlantic Compact.It was the only facility open to all states(except North Carolina) as of mid-2000and expects to accept limited amounts ofnon-Atlantic compact waste in thefuture.

• Clive, Utah, which accepts large-volumebulk forms of low-level waste, such assoils and building debris that are notroutinely accepted by the Richland orBarnwell sites.

DOE also has seven major low-level wastedisposal sites (Figure 24) to dispose ofwastes resulting from defense-related activi-ties, research, and cleanup.

Under the 1980 Low-Level RadioactiveWaste Policy Act, each state must takeresponsibility for the non-defense relatedlow-level waste generated within its bor-ders. States can act on their own or in acompact with other states. They have estab-lished processes for studying and selectingnew disposal sites in consultation with citi-zens and experts and in accordance withfederal and state regulations. By July 1,2000, 44 states had entered into 10 com-pacts. None of the compacts or states actingalone had successfully opened a new dispos-al facility (Figure 25) by that date, however.

Disposal facilities must be designed, operat-ed, and controlled after they are sealed toensure that the maximum annual radiationexposure to any individual from the sitedoes not exceed 25 millirem per year.Actual exposures from existing commercialfacilities have been considerably lower thanthat figure.

Mixed Waste

Waste containing both radioactive materialand hazardous chemicals must be treated anddisposed of in accordance with the separatelaws governing the two different types ofwaste.

• Under RCRA, EPA and authorized statesregulate hazardous waste. RCRA requiresthat low-level mixed waste be treatedbefore it is sent to an authorized commer-cial land disposal facility. Technologies,such as incineration and solidification,reduce its toxicity or volume and helpensure that hazardous materials will notmigrate into the environment.

• Under the Atomic Energy Act, NRC,DOE, or authorized NRC “Agreement”states are responsible for radioactivewaste. High-level and transuranic mixedwaste is handled in much the same way asregular high-level or transuranic radioac-tive waste.

A number of commercial facilities areauthorized to treat, store, and dispose ofmixed waste. These facilities include:

• Envirocare of Utah, Inc., Clive, Utah



4


49

• Diversified Scientific Services, Inc.,Kingston, Tennessee

• Molten Metal Technology, Waltham,Massachusetts

• NSSI, Houston, Texas

• Perma-Fix Environmental Services, Inc.,Gainesville, Florida.

The Search for PermanentDisposal SolutionsProposed High-Level WastePermanent Disposal Site

DOE has been evaluating a potential high-level radioactive waste disposal site at YuccaMountain, Nevada, since 1987. (Figure 26)However, DOE has been unable to moveforward with final site selection because ofscientific complexities and strong politicalopposition in Nevada and elsewhere.

In the Nuclear Waste Policy Act of 1982,Congress called for the development of amined geologic repository to dispose ofspent fuel and high-level radioactive waste.DOE identified nine potential sites in 1983

and selected three as candidates for furtherstudy in 1984. In 1987, Congress directedDOE to limit its study to the YuccaMountain site and to determine whetherthe site would be suitable for developmentas a repository.

Under the timetable set by Congress in the1980s, a permanent repository would havebegun receiving spent fuel by February1998. By late 1998, however, DOEannounced it would not be ready to make arecommendation on the suitability of theYucca Mountain site until 2001. The earli-est DOE anticipates operating a YuccaMountain repository is 2010, and manyobservers believe even this timetable isoptimistic.

Meanwhile, according to the NuclearEnergy Institute, the nation’s nuclear elec-tric utilities and their customers have com-mitted more than $14 billion, includinginterest, to a Nuclear Waste Fund. Thisfund is to pay for the government’s spentfuel management program, including thepermanent repository, an interim storagefacility, and the transportation of spent fuel.

How AreRadio-active

WastesManaged?

The Searchfor

PermanentDisposalSolutions

�

Idaho Nat'l Eng. and Env. Lab

�Fernald

�Oak Ridge

�Savannah River Plant

� Nevada Test Site

�

�Richland

�Envirocare

�

�Bamwell

Commercial LLW Disposal Site

Dept. of Energy or Dept. of Defense Disposal Site

Los Alamos

�

�

Hanford


Figure 24. Map of low-level waste disposal sites

4


50

It will cost about $4 billion of that moneyto determine if the Yucca Mountain site issuitable.

Public Concerns about PermanentDisposal Options

In its March 1995 report, Future Issues in

Environmental Radiation, a subcommittee ofthe EPA’s Science Advisory Board (SAB)listed radioactive waste management as oneof the seven radiation-related issues mostlikely to have a significant impact on thefuture quality of the environment. Public


Radioactive WasteCleanup

Source: LLW Forum, Inc.


Figure 26. Artist’s sketch of proposed Yucca Mountain disposal facility

Figure 25. Map of low-level waste state compacts

4


51

apprehensions about disposal risks are a sig-nificant impediment to achieving perma-nent solutions. Here are some excerpts fromthe SAB report:

Regardless of their categorization, radioactivewastes and the solutions proposed for thedisposal problem are feared by many mem-bers of the public. This creates a challengingdilemma: on the one hand, the public’s per-ception of the risk of the materials arguesstrongly for ultimate disposal; on the other,potential risks of the disposal itself are usedby opponents to argue against these efforts.

As a result of this conflict, disposal is in astalemate. Although a majority of the publicindicates that radioactive wastes should bedisposed of permanently, progress toward thisgoal is slow, with numerous setbacks, for anyform of wastes. On-site storage of high-levelradioactive waste is reaching capacity at somelocations, and the risks of such storage canonly increase as these wastes accumulate ….

As the stalemate continues, waste materialinventories continue to accumulate on site inless-than-optimal places such as hospitals …laboratory and university storage rooms andbuildings … and on reactor sites. Most ofthese locations were selected for featuresother than isolation of waste materials, (and)continued reliance on their use increases thelikelihood of the development of radioactivecontamination on these sites, and/or releaseto the environment ….

The scientific community believes that feasi-ble disposal options exist to ensure the long-term isolation of most forms of radioactivewastes; what is lacking is the requisite publicsupport for applying the technologies.

Radioactive Waste CleanupOne of the most difficult and expensiveradiation-related challenges facing thenation in the next century will be to com-plete the cleanup of contaminated sites.More than 100 nuclear weapons productionsites and thousands of facilities have beencontaminated by radioactivity and radioac-tive waste. This cleanup job will last wellinto the twenty-first century. The contami-

nation is primarily the result of the nation’sarms race with the former Soviet Unionduring the Cold War years following WorldWar II, when a huge industrial complexproduced and managed thousands of nuclearweapons.

In addition, radioactive waste from disman-tled nuclear reactors, hospitals that usenuclear medicine, and research laboratoriesand other facilities that generate low-levelwaste will require continuing disposalefforts.

Nuclear Weapons Waste

DOE is responsible for the bulk of thenuclear weapons cleanup. In its 1995 reporton its cleanup effort, Closing the Circle onthe Splitting of the Atom, DOE characterizedthe waste and contamination from nuclearweapons production as “a task that had, forthe most part, been postponed into theindefinite future,” adding: “That future isnow upon us.”

DOE’s nuclear weapons complex consists of16 major sites and dozens of smaller sitesacross the United States. According to the

How AreRadio-active

WastesManaged?

Radioactive Waste

Disposal

Figure 27.DOE’s Hanford site


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52

the soil and sediments. Leaking drumsfilled with plutonium-contaminated wastewere stored in the 1950s and early 1960soutside in an area near the plant. Whenworkers tried to clean up contaminatedsoil in the late 1960s, strong winds blewplutonium-contaminated dust across alarge area, spreading the contaminationand threatening the safety of cleanupworkers.

DOE has begun cleaning up the weaponscomplex. Some sites have been fully decon-taminated and turned over for other uses.DOE is working to:

• Develop more effective remediation tech-nologies,

• Involve the public in decisions aboutwhere and how to treat and dispose ofnuclear waste, and

• Involve the public in decisions about thefuture of decontaminated sites.

But the job will not be finished until 2070at the earliest. Meanwhile, places likeHanford and Rocky Flats will continue topose some of the nation’s most urgent andhigh-risk radiation management problems.

Nuclear Reactor Waste

Every 12 to 24 months, each nuclear reac-tor is shut down, and the oldest fuel assem-blies—those that have become depleted inuranium fuel—are removed from the reac-tor. Each year, the 100-plus operatingnuclear power plants in the United Statesproduce about 2,000 metric tons of high-level radioactive waste in the form of spentfuel.

While the material is highly radioactivewhen removed from the reactor, it losesabout 50 percent of its radioactivity in threemonths and about 80 percent after a year.About one percent remains radioactive forthousands of years. Because the UnitedStates has not yet built a permanent reposi-tory for long-term disposal of spent fuel (seeSites and Methods of Waste Disposal, thisChapter, page 46), the fuel assemblies aretemporarily stored at the reactor site. Steel-lined, concrete vaults filled with water,

DOE report, every site in the nuclearweapons complex is contaminated to somedegree with radioactive or hazardous materi-als. Buildings, soil, air, ground water, andsurface water at the sites are contaminated.EPA sets the criteria for cleaning up thecontamination at these facilities. Somebuildings and sites have been cleaned up,but DOE says that most sites have “signifi-cant and complicated problems that havebeen compounded over several decades.”

One of the most troubling examples of theAtomic Age’s environmental legacy isDOE’s Hanford Site in Washington State(Figure 27). It is home to almost two-thirds,by volume, of the entire solid and liquidhazardous and radioactive wastes created bythe nuclear weapons program. This volumeincludes more than 50 million gallons ofhigh-level radioactive waste stored inunderground tanks.

Severe contamination problems at theHanford site include:

• One million gallons or more of high-levelmixed waste believed to have leaked fromHanford’s deteriorating storage tanks,some of which are at risk of exploding

• Radioactive tritium and other radionu-clides detected in the ground water atHanford which threaten to contaminatethe Columbia River

• Widespread contamination with radioac-tive iodine released from early operationsat the Hanford Site

• Large buildings where spent fuel wasreprocessed at the Hanford Site (and theSavannah River Plant in South Carolina)so contaminated with radioactive materi-als that decontamination must be done byremote control to protect the workers

Other weapons sites have similar problems.

• At Fernald, Ohio, several hundred tons ofuranium dust were released into theatmosphere and a local river, and drink-ing water wells were contaminated withuranium.

• At the Rocky Flats Plant in Colorado,traces of plutonium have been found in




53

called spent fuel pools, and above-groundsteel or steel-reinforced concrete containerswith steel inner canisters are usually usedfor storage. (Figures 28)

The nuclear reactor structures, which pro-duce radioactive spent fuel, themselvesbecome radioactive over time. Eventuallythey must be shut down, and cleaned up,dismantled, or sealed off until the radioac-tivity has decayed to a point where it nolonger presents a hazard.

These processes, called decontamination anddecommissioning, produce additional quanti-ties of low-level radioactive waste, as well asfission products and other radioactive com-ponents that require safe and secure storage or disposal. Some of the contaminatedmetal from reactors may be salvaged andrecycled for other uses. (See OrphanedSources and Contaminated Scrap Metal inthis Chapter, page 54.)

Low-Level Radioactive Waste

Government facilities, nuclear reactors, fuelfabrication facilities, uranium fuel conver-sion plants, industries, universities, researchinstitutes, and medical facilities generatelow-level radioactive waste. In addition toDOE facilities, more than 22,000 commercialusers of radioactive materials generate someamount of this waste. The cleanup of con-

taminated buildings and sites will generatestill more low-level waste in the future.

Only about one percent of the total low-level waste stream comes from hospitals,medical schools, universities, and researchlaboratories. Much of this waste can be safe-ly stored on site until its radioactivity hasdecayed to background levels.

NRC regulates the medical, academic, andindustrial uses of nuclear materials genera-ted by nuclear reactors through a compre-hensive inspection and enforcement pro-gram. Some 32 states have entered intoagreements with NRC to assume regulatoryauthority over certain radioactive materials,including some radioisotopes.

As disposal costs have gone up, large-quan-tity waste generators have increasinglyturned to predisposal waste processing toreduce the volume of low-level waste thatmust be sent to disposal facilities. Thisinvolves measures such as:

• Separating radioactive from nonradioac-tive components

• Incinerating waste at specially designedincinerators

• Using hydraulic presses to compact thewaste before it is packaged for disposal,which can reduce the volume of bulkwaste by up to 90 percent

• Decontaminating, reusing, or recyclingradioactive materials whenever possible

While these activities significantly reducethe volume of waste to be disposed of, theyalso concentrate the radioactivity and thusrequire more stringent disposal safeguards.

Low-level wastes must be properly packagedand disposed of to minimize the chance ofexposure to people or the environment.Disposal sites must have features that willisolate the waste from the environment.Radiation levels around disposal facilitiesmust be monitored carefully to ensure thatthey meet regulatory standards.

How AreRadio-active

WastesManaged?

Radioactive Waste

Disposal


Figure 28.Spent fuel in pool storage at a nuclear power plant

4

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54

Orphaned Sources andContaminated Scrap Metal

Many DOE reactors have been shut downin recent years, and hundreds of reactors,processing facilities, and storage tanks willbe dismantled as part of the cleanup fromthe nation’s nuclear weapons program. (SeeNuclear Weapons Waste in this Chapter,page 51.) Dismantling these facilities cre-ates large amounts of scrap steel and othermetals, some of which is contaminated byradioactivity.

Scrap metal and other waste can also becontaminated by so-called orphaned radioac-tive sources. These are primarily specializedindustrial devices, such as those used formeasuring the moisture content of soil andthe density or thickness of materials. Thesedevices often contain a small amount ofradioactive material sealed in a metal casingor housing. If equipment containing asealed radioactive source is disposed ofimproperly or sent out for recycling, thesealed source may wind up in a metal recy-cling facility. If the item does not havemarkings identifying its original owners, thesource is called an orphaned source.

Approximately 200 lost, stolen, or aban-doned licensed sources are reported eachyear. Orphaned sources are one of the mostfrequently reported radioactive contami-nants in shipments received by scrap metalfacilities. If an orphaned source is meltedduring reprocessing, it can contaminateentire batches of scrap metal, the processingequipment, and even the entire facility. Theradiation can also pose a hazard to facilityworkers and to consumers if contaminatedrecycled metal were to be used in consumerproducts.

EPA is working with state, federal, andinternational radiation protection organiza-tions to ensure a national supply of cleanmetal for general use. In 1998, EPA deter-mined that uncontrolled, orphaned sourcesand contaminated metal imports pose ahigher risk to the public and workers thanthe recycling of scrap metal from nuclearfacilities (which is only one tenth of one

percent of the metal used in the UnitedStates annually). Therefore, EPA has direct-ed its efforts towards orphaned waste andcontaminated metal imports as the moresignificant problem.

The agency’s orphaned sources initiative,now being carried out in conjunction withthe Conference of Radiation ControlPrograms Directors, has established anationwide system that provides quick andeffective information on identification,removal, and disposal of orphaned sources.

The lesser problem, preparation of contami-nated scrap metal from domestic nuclearfacilities for recycling, continues to followguidance developed by the NRC and DOEin the 1970s. These standards apply tomaterials that are contaminated on the sur-face only and can be decontaminated.DOE suspended the recycling of all contam-inated metal in July 2000.

Naturally Occurring RadioactiveMaterials

Radioactive materials that occur in natureand become concentrated through humanactivities (such as mineral extraction andprocessing) are considered radioactivewastes. These are receiving increasingattention from the federal and state govern-ments.

These materials are known as NORM (nat-urally occurring radioactive materials) orTENORM (technologically enhancedNORM). They are a subset of a broader cat-egory of wastes, NARM (naturally occuringand accelerator-produced radioactive mate-rials) which also includes radioactive wasteproduced during the operation of atomicparticle accelerators for medical, research,or industrial purposes. (See Types ofRadioactive Waste in this Chapter, page46.) The radioactivity contained in thewaste from accelerators is generally shortlived, less than one year, and constitutes avery small percentage of the nation’s totalradioactive waste stream.

NORM and TENORM, however, are ofgrowing concern because some of this waste



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contains relatively high concentrations ofradioactivity. Even NORM with a lowerconcentration of radioactivity can pose dis-posal problems because of its high volume.Metal mining and processing, for example,will generate an estimated 20 billion metrictons of waste over the next 20 years.NORM is also a problem because some of itis used in construction, concrete, and road-building, resulting in contamination of theenvironment and possible human radiationexposure.

There were no federal regulations coveringdisposal of NARM with high radioactivityconcentrations as of mid-2000. EPA isworking to improve the government’sunderstanding of the radiological hazardsposed by all these materials, and is workingwith the states as they develop guidancerelated to NORM and TENORM. At therequest of Congress, EPA sponsored a studyof guidance and risk assessment approachesto TENORM. This study was conducted bythe National Academy of Sciences andcompleted in January 1999.

Transporting Radioactive WasteThe federal government’s plans to createpermanent disposal facilities for radioactivewaste lead to continuing public concernover the safe transport of these hazardousmaterials to their final resting places. Tensof thousands of shipments will be requiredto dispose of spent fuel from the nation’snuclear reactors, high-level defense wastestored in nuclear weapons complexes, andtransuranic waste designated for the WIPPin New Mexico. Even more shipments willbe needed for the continuing stream of low-level waste.

Two federal agencies, DOT and NRC, areprimarily responsible for overseeing radioac-tive waste transportation. They must mini-mize the risk of any accidental releases ofradiation and carry out a range of regulations:

• All radioactive waste shipments mustcomply with federal standards for packag-

ing, labeling, handling, loading, andunloading.

• Transportation workers must be highlyqualified and receive special training.

• Shipment routes must follow federalguidelines, avoiding highly populatedareas wherever possible.

• Transport vehicles for some waste typesmust meet special safety standards,including capabilities for satellite trackingand constant communication.

• Drivers and state and local officials mustreceive special emergency response training.

High-level and transuranic wastes must betransported in airtight, specially shieldedstainless steel containers designed to pre-vent radioactive releases even in a severeaccident or other emergency. The contain-ers (Figures 29 and 30), constructed withinner and outer containment vessels, mustsurvive extreme durability tests includingthe following:

• A 30-foot fall onto a steel-reinforced con-crete pad

• A 40-inch drop onto a 6-inch steel spike

• A 30-minute exposure to a fire of 1,475degrees Fahrenheit

How AreRadio-active

WastesManaged?

TransportingRadioactive

Waste

Figure 29.Truck transporting radioactive waste


4

• Submersionin 50 feetof water foreight hours

Some criticscontinue toquestion thesafety ofradioactivewaste ship-ments andthe adequacyof containertesting. Todate, howev-er, the safetyrecord forwaste ship-ments hasbeen good,much betterthan for ship-ments of other hazardous materials.

As of mid-1998, four accidents hadoccurred during spent fuel shipments. Noneof them released radioactive material.Between 1971 and 1999, 62 accidentsoccurred during the transport of low-levelradioactive waste in the United States. Ofthese, only four resulted in the release ofradioactive materials. The radioactive mate-rial was quickly cleaned up and repackagedwith no measurable radiation exposure topeople along the routes or to the emergencyresponse personnel.


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TransportingRadioactiveWaste

Figure 30. Transuranic Waste shipping containers


5How Is the Public Protectedfrom Radiation?


57

The U.S. government and state govern-ments play important roles in ensuring thatradiation is responsibly managed to protectthe public and the environment from therisks of exposure to ionizing radiation.Other organizations, including local govern-ments, Native American Tribes, and inter-national bodies, share in this responsibility.

Each of us as individuals also plays a keyrole by learning about radiation and makingour opinions known in writing or at publicforums and meetings. Individuals can havean effect on decisions about such issues as:

• Balancing the benefits and risks of radiation

• Safe disposal of radioactive waste

• Appropriate levels of cleanup for contam-inated sites and facilities

Each of us, as individuals, can also take rea-sonable precautions to limit our own exposure.

This chapter provides an overview of howthese public and individual responsibilitiesfor protection from the harmful effects ofradiation are carried out. Topics include:

• Government Responsibilities inProtecting the Public

• Government Controls on Exposure toRadiation

• Major Federal Legislation

• Responsible Federal Agencies

• Federal, State, and Local GovernmentFunctions

• Other Roles in Managing Radiation

Government Responsibilities inProtecting the PublicThe federal government’s primary responsi-bilities in protecting the public include:

• Educating the public on radiation and itsbenefits and risks

• Regulating the storage, transportation,and disposal of radioactive waste

• Controlling the sources and uses of radia-tion, and setting and enforcing protectivestandards

• Conducting research to determine poten-tial health effects and to find more effec-tive ways to reduce radiation exposures

• Providing guidance on appropriate pre-cautions by individuals

The first two responsibilities above havebeen discussed in previous chapters. Thischapter discusses appropriate precautionsindividuals can take against overexposure,governmental controls and standards for useof radiation, and government researchresponsibilities.

Controlling Risks of Exposure toRadiation: Federal and IndividualRoles

The federal government regulates manmadeand some naturally occurring radioactivematerials by setting emissions, exposure,and cleanup standards. Allowable exposurelevels are set to provide the appropriatelevel of protection for both workers and thepublic. (Table 4) The federal governmentbegan setting radiation standards in 1957.NRC and EPA have primary responsibility

How Is the PublicProtected

fromRadiation?

GovernmentResponsibilities

in Protectingthe Public

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for radiation protection except at DOEfacilities where DOE regulates its radiation-related activities.

In 1995 the U.S. Environmental ProtectionAgency’s Science Advisory Board (SAB), apanel of independent experts that advisesEPA on the scientific aspects of its regulato-ry responsibilities, studied the current stateof knowledge about radiation and providedEPA with guidance on how it shouldapproach radiation issues for the next 30years. The SAB report, Future Issues inEnvironmental Radiation, concluded that:

• High priority governmental controls oversources and standards of radiation arealready in place and undergoing continualrefinement.

• The greatest potential for further reduc-tion in public exposure is through indi-vidual protective actions.

The SAB found that the greatest potentialfor reducing overall public exposure to con-trollable sources of radiation was notthrough more government regulation, butby individual action, primarily by avoidingunnecessary exposure to medical radiationand by reducing exposure to indoor radon.

How You Can Limit Your RadiationExposure?

Some recommended precautions that allindividuals should take to limit exposure toradiation include:

• Test your home for radon, and reduceradon levels if necessary. (See HealthEffects of Radon, Chapter 3, page 37, andControlling Exposure to Radon in thisChapter, page 61.)

• Evaluate medical uses of radiation, andweigh benefits and risks. (See ControllingMedical Exposures in this Chapter, page60.)

• Minimize exposure to ultraviolet radia-tion from the sun by:

—Wearing protective clothing and sun-glasses

—Wearing sunscreen

— Limiting exposure to midday sun

• Participate in public decision-makingon issues such as facility sites and stan-dards.

You will find more details on some of theseprecautions in the following sections.

How Is the PublicProtectedfromRadiation?

GovernmentResponsibilitiesin Protectingthe Public

Table 4: Dose Standards for ionizing radiation exposure in theUnited States (expressed in terms of annual effective dose)

Population and source of radioactivity Dose Limit(mrem/yr)

Occupational limit 5,000

General Public

Limit for any licensed facility (excluding medical) 100

Limit for nuclear power facility 25

Limit for waste repository (excluding Yucca Mountain) 15

NAS recommendation for Yucca Mountain 2-20

EPA recommended “action level” for indoor radon 800 (approx.)

Source: Lawrence Berkeley National Laboratory

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Government Controls onExposure to RadiationControlling Radiation in the Air

Radioactive materials can enter the atmos-phere several ways:

• By natural processes, such as the interac-tion of cosmic radiation with nitrogen toproduce radioactive carbon-14

• By human activities that generate radia-tion or enhance natural radiation

• By wind or some other natural or humanactivity stirring up dust containingradioactive particles

Once airborne, particles can remain sus-pended in the air for a long time, or theycan settle in water, on the soil, or on sur-faces of plants, where they can enter thefood chain. Rain or snow can also removeradioactive particles from the air. (Figure 31)

Under the Clean Air Act of 1970 and itsamendments, EPA established standards toregulate the release to the air of manmaderadiation by most governmental and indus-trial facilities.

• EPA’s National Emissions Standards forHazardous Air Pollutants for radionuclidesrequire facilities to limit their radionu-clide air emissions so that no member ofthe public is exposed to more than 10millirem of radiation per year.

• Facilities must submit annual reports doc-umenting their emissions, and they maybe subject to annual inspections.

Facilities regulated by NRC, such as nuclearpower plants, hospitals, medical researchfacilities, research reactors, and uraniumfuel cycle facilities, are subject to similarlimits.

EPA is also responsible for taking steps toreduce indoor exposures from radon. (SeeHealth Effects of Radon, Chapter 3, page 37and Controlling Radon Exposure in thisChapter, page 61.)

Controlling Radiation in Water

Radioactive materials can enter water inseveral ways:

• By being deposited in surface water fromthe air

• By entering groundwater or surface water


fromRadiation?

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on Exposureto Radiation


Figure 31. Major pathways by which dispersed radionuclides can affect living organisms

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from the ground through erosion, seepage,or human activities such as mining

Some radioactive particles dissolve andmove along with the water. Others aredeposited in sediments or on soil or rocks.

Two federal laws govern the regulation ofradiation in water:

• The Safe Drinking Water Act (SDWA) directed EPA to set standardsfor drinking water contaminants that mayadversely affect human health. Under theSDWA, EPA set limits for some radioac-tive materials in drinking water. Publicwater supplies must comply with EPA’snational primary drinking water regula-tions, which are based on the agency’sdrinking water standards.

In November 1999, EPA proposed aNational Primary Drinking WaterRegulation (NPDWR) for radon in drink-ing water based on a multimedia approachdesigned to achieve greater risk reductionby addressing radon risks in indoor air,with public water systems providing pro-tection from the highest levels of radon intheir ground water supplies. The frame-work for this proposal is set out in theSafe Drinking Water Act as amended in1996. This statutory-based frameworkreflects the characteristics uniquely specif-ic to radon among drinking water con-taminants. SDWA directs EPA to promul-gate a maximum contaminant level(MCL) for radon in drinking water, butalso to make available a higher alternativemaximum contaminant level (AMCL)accompanied by a multimedia mitigation(MMM) program to address radon risks inindoor air.

For more information on radon in drink-ing water, call EPA’s Drinking WaterHotline (1-800-426-4791) or visit theEPA Web site at www.epa.gov/safewater.

• The Federal Water Pollution ControlAct, as amended by the Clean WaterAct, prohibits the discharge of radioac-tive wastes or other pollutants into U.S.navigable waters without a permit. EPAand authorized states have the authority

to issue permits in accordance with waterquality standards.

The government also controls radiation inwater by requiring low-level radioactivewaste disposal facilities to be located awayfrom floodplains. These facilities are alsodesigned to divert water away from thewaste, or collect and remove radionuclidesfrom water that has come in contact withthe waste. This precaution minimizes theamount of radioactive material released intowater, keeping it out of the food chain andaway from people.

Controlling Medical ExposuresGovernment Controls and Guidance

The U.S. Food and Drug Administration(FDA) and other federal and state agenciesregulate medical procedures that use radia-tion. Radiologists, health physicists, NRC,EPA, state agencies, the National Councilon Radiation Protection and Measurements,and other responsible parties are continuallylooking for ways to reduce risk while takingadvantage of the benefits from medical usesof radiation.

Government agencies also issue guidancedesigned to reduce unnecessary use of radia-tion in diagnosis and treatment and toensure that technicians, equipment, andtechniques meet standards that minimizeradiation exposure. Within these standards,however, patients and health care providersmust decide when to use radiation on acase-by-case basis.

The National Institutes of Health (NIH)points out that the radiation doses involvedin medical procedures have been decreasingover the past two decades as X-ray films andequipment have been improved. In addi-tion, the ability to target radiation moreprecisely to one part of the body has result-ed in less exposure to the rest of the body.In the NIH’s view, with the development ofbetter machines and the use of computers toplan treatment, the safety and effectivenessof radiotherapy has steadily improved.


ControllingMedicalExposures

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In the overwhelming majority of cases,according to NIH, “the benefits of medicalradiation far outweigh the risks associatedwith it.” For example:

• Diagnostic tests using radiation allowdoctors to treat patients without usinginvasive and life-threatening procedures.

• Radiation, surgery, and chemotherapy arethe mainstays of cancer treatment and areused in combination, depending on thecancer.

• Certain tumors can be treated successfullywith radiotherapy alone.

“But,” notes the NIH, “there is a tradeoff.In this sense, radiation is no different thanany other diagnostic or therapeutic agent,except that we have more information thanusual.” For example, doctors try to avoidexposure of large parts of the body to radia-tion because this can cause serious sideeffects like cancer. About five percent of allsecondary cancers—cancers that developafter treatment for the initial cancer—havebeen linked to radiotherapy.

Individual Actions You Can Take

You can minimize your exposure from med-ical radiation by taking these actions:

• Discuss your treatment with your doctorto determine if it is really the best alter-native.

• Ask if MRI (magnetic resonance imag-ing), ultrasound, and other nonionizingdiagnostic techniques are possibleoptions.

• Get a second opinion if you have anyreservations.

• Always avoid radiation exposure if youhave reason to believe it is unnecessary.

Controlling Exposure to RadonGovernment Guidance

EPA and the U.S. Surgeon General recom-mend testing all homes below the thirdfloor for radon and taking steps to reduceindoor radon levels to below four picocuries

per liter (pCi/L), the level above whichEPA recommends that homeowners volun-tarily take steps to reduce radon exposures.This level is cost and technology-based,meaning that it takes into account the lim-its of the technology currently available andaffordable to address residential radon lev-els. There is currently no known safe levelof exposure to radon decay products. Anylevel of exposure, no matter how small, maypose some increased risk of lung cancer.(See Health Effects of Radon, Chapter 3page 37.) Testing your home is the only wayto know if you and your family are at riskfrom radon in indoor air.


Testing for radon is easy:

• Buy a low-cost, radon test kit from a qual-ified laboratory through the mail or inhardware and home-improvement stores.

• Hire a professional to do the testing. Inthis case, EPA recommends choosing aqualified measurement company or indi-vidual (e.g., home inspector). Check withyour state radon office; most states requireradon professionals to be licensed, certi-fied or registered.

If you find high radon concentrations:

• A variety of methods are used to reduceradon in homes, schools, and other build-ings. Simple systems using pipes and fansmay be used to reduce radon. Such sys-tems are called sub-slab depressurizationand do not require major changes to ahome. These systems remove radon gasfrom below the concrete floor and thefoundation before it can enter the build-ing.

• The typical cost for a contractor to installa sub-slab depressurization system rangesfrom $500 to $2500, about the same costas other common home repairs and rou-tine maintenance.

• With the technology available today, ele-vated radon levels can be reduced tobelow four pCi/L more than 95 percentof the time, and to below two pCi/L an


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estimated 70 to 80 percent of the time.

New homes can be built to be radon-resist-ant.• In many areas of the country, construc-

tion of new homes with radon-resistant features is becoming common practice or is required by code.

• EPA estimates the costs of building newhomes radon-resistant to be about $350to $500.

EPA has developed a number of publica-tions on radon which provide informationon how indoor air radon problems can befixed. (See Appendix C.) EPA also has aNational Radon Program to inform the pub-lic about radon risks, provide grants forstate radon programs, and develop standardsfor radon-resistant buildings. For moreinformation, call EPA’s radon hotline (1-800-SOS-Radon) or visit EPA’s web site(www.epa.gov/iaq/radon).

Monitoring Radiation Levels inthe EnvironmentTo keep track of levels of radioactivity inthe air, water, and food chain, EPA operatesa national network of monitoring stations.The Environmental Radiation AmbientMonitoring System samples air, precipita-tion, surface and drinking water, and milkto track any radioactivity that reaches thepublic through the different environmentaland food pathways. The system processesabout 2,000 samples per month and con-ducts 6,000 analyses of the data, which arepublished in the quarterly journalEnvironmental Radiation Data. These reportscan also be viewed at www.epa.gov/narel.

Controlling UV RadiationExposureOverexposure to the sun's ultraviolet (UV)rays threatens human health by causing:

• Immediate painful sunburn

• Skin cancer

• Eye damage

• Immune system suppression

• Premature aging

Children are highly susceptible to harmfulUV radiation. Just one or two blisteringsunburns in childhood may double the riskof developing melanoma, a highly malig-nant form of skin cancer. An estimated 80percent of lifetime sun exposure occursbefore the age of 18.


Sunburn, skin cancers, and other sun-relat-ed adverse health effects are largely prevent-able when sun protection is practiced earlyand consistently. The best sun protection isachieved by practicing a combination ofrecommended sun-safe behaviors:

• Limit sun exposure during the hourswhen the sun’s rays are the strongest,between 10am and 4pm.

• Seek shade, such as trees or umbrellas,whenever possible.

• Wear a wide-brimmed hat, sunglasses, andlong-sleeved, tightly woven clothing.

—A wide-brimmed hat protects the facefrom direct sun’s rays but not from raysreflected from lower-level surfaces.

—Clothing can physically block out thesun's harmful rays.

—Sunglasses can block out 100 percent ofUVA and UVB radiation to protect theeyes from damage.

• Use a broad-spectrum sunscreen with asun protective factor (SPF) of at least 15.

• Avoid tanning salons. Artificial UV radi-ation can be as damaging as sunlight.

• Limit exposure to reflective surfaces suchas snow and water. UV rays can bereflected off of sand, tile, water, snow, andbuildings.

Controlling OccupationalExposuresPeople who work at nuclear power plants orin laboratories where radioactive materialsare used, wear thermoluminescent dosime-ters (TLDs) and/or film badges on the job.These devices measure cumulative whole-body exposures to ensure the exposure isnot above regulatory limits.


ControllingUV RadiationExposure

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Table 5

MajorFederal

Legislationon Radiation

Protection

Table 5: Major Federal Legislation on Radiation Protection

Law YearPassed

Agencies Description

The AtomicEnergy Act(AEA)

The Clean AirAct (CAA)

TheComprehensiveEnvironmentalResponse,Compensation,and LiabilityAct (CER-CLA), asamended by theSuperfundAmendmentsandReauthorizationAct (SARA)

The EnergyPolicy Act

The FederalWater PollutionControl Act, asamended by theClean WaterAct

1946,amended in1954

1970, amended in1977and 1990

1980, amendedin 1986

1992

1972,amendedin 1977 and 1987

NRCEPA DOE

EPA

EPA

EPANRCNAS

EPA

• Establishes roles and responsibilities for con-trol of nuclear materials. NRC, DOE, andEPA manage use, possession, and disposal ofregulated materials.

• Charges EPA with setting generally applicableenvironmental standards to protect the envi-ronment from listed radioactive materials.EPA has issued standards for (a) environmen-tal releases of radioactivity from nuclear fuelcycle facilities (nuclear power reactors andsupporting facilities), (b) disposal of radioac-tive materials from uranium ore refining, and(c) the disposal of high-level and transuranicradioactive waste anywhere except YuccaMountain.

• Establishes the National Emissions Standardsfor Hazardous Air Pollutants to regulate airpollution from various sources.

• Section 112 applies specifically to airborneemissions or releases of radionuclides (radioac-tive particles) into the environment andrequires EPA to protect public health and theenvironment from these emissions. EPAdeveloped standards that limit air emissions ofradionuclides to the environment from varioussources. EPA implements these standardsacross the country through its regional offices.

CERCLA and SARA require that cleanup ofhazardous substances be conducted in a mannerprotective of human health. EPA has establishedsite-specific methods to implement the missionestablished by CERCLA as it relates to cleanupand remediation of radioactively contaminatedsites.

Directs the NAS to develop scientific recom-mendations and EPA to issue public health andsafety standards for the operation of the poten-tial high-level nuclear waste repository at YuccaMountain. NRC will implement EPA’s standardsfor Yucca Mountain.

Prohibits discharge of radioactive wastes or otherpollutants into U.S. navigable waters without apermit. EPA and authorized states have authorityto issue permits in accordance with nationalwater quality standards.

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Table 5

MajorFederalLegislationon RadiationProtection

Table 5: Major Federal Legislation on Radiation Protection, con’t

Law YearPassed Agencies Descriptions

The HazardousMaterialsTransportationAct

The IndoorRadonAbatementAct

The Low-LevelRadioactiveWaste PolicyAct

The NuclearWaste PolicyAct

The SafeDrinkingWater Act(SDWA)

The UraniumMill TailingsRadiationControl Act(amendmentto AEA)

The WasteIsolation PilotPlant LandWithdrawalAct

1975

1988

1980

1982,amended in 1987

1974, amendedin 1996

1978

1992

DOT

EPA

States

DOE

EPA

DOE NRCEPA

DOE

Authorizes the DOT to set standards for thetransport of radioactive and other hazardousmaterials in interstate and foreign commerce.

Instructs EPA to reduce indoor exposures fromradon.

Makes each state responsible for ensuring thatadequate disposal capacity is available for com-mercial low-level nuclear waste generated withinits borders. Encourages states to join compacts todevelop needed disposal capacity.

• Authorizes DOE to develop two geologicrepositories to dispose of civilian spent nuclearfuel.

• Assigns responsibilities for nuclear waste man-agement to specific federal agencies and cre-ates the Nuclear Waste Fund to pay fornuclear waste disposal costs from nuclearpower user fees.

• Charges EPA with developing generally appli-cable standards for repositories and NRC withdeveloping specific technical requirements.

• 1987 amendment directs DOE to investigateonly one potential repository site: YuccaMountain, Nevada.

Requires EPA to publish standards for drinkingwater contaminants that may adversely affecthuman health. EPA has set limits on radionu-clides in drinking water along with numerousother physical, chemical, and biological constituents.

• Directs DOE to provide for stabilization andcontrol of uranium mill tailings from inactivesites in a safe and environmentally soundmanner to minimize radiation hazards to thepublic. DOE is cleaning up 24 sites and morethan 5,000 “vicinity properties” (contaminat-ed off-site locations).

• Charges EPA with developing standards ofgeneral application for both inactive andactive uranium mill tailings sites.

• Directs NRC to regulate operation and closureof active uranium mill tailing sites.

Gives EPA regulatory oversight authority overmany of DOE’s activities at the WIPP in south-eastern New Mexico near Carlsbad.

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Radiation workers are also rigorouslytrained to handle radioactive materials safe-ly, to protect themselves and the publicfrom possible radiation hazards. The respon-sible authorities and government agencies,in order to determine the cause and helpprevent recurrences, investigate accidentsthat result in even slight radiation exposureor the release of small amounts of radioac-tivity. If an investigation reveals careless-ness or neglect, the government can imposeheavy fines and even shut down the respon-sible facilities.

Responsible Federal AgenciesThe federal government’s radiation manage-ment and protection programs are author-ized by more than 20 laws enacted since1946. Table 5 outlines the major laws feder-al agencies use to set standards and issueregulations for radiation protection.

Nuclear Regulatory Commission(NRC)NRC protects public health and safety andthe environment by ensuring that nuclearmaterials are used safely. NRC’s regulatoryfunctions apply to both nuclear powerplants and other civilian users of nuclearmaterials, including nuclear medicine athospitals, academic activities at educationalinstitutions, research, and industrial appli-cations. NRC ensures that these facilitiesoperate in compliance with strict safetystandards by:• Licensing facilities that possess, use, or

dispose of nuclear materials

• Establishing standards governing theactivities of licensees

• Inspecting licensed facilities to ensurecompliance with its requirements

NRC carries out its programs either directlyor through the Agreement State Program, inwhich NRC relinquishes its regulatoryauthority for most facilities to qualified par-ticipating states. Under this arrangement,Agreement States perform the licensing andinspection functions. They must provide at

least as much health and safety protectionas NRC standards prescribe.

NRC limits the amount of radiation thatworkers or members of the public can beexposed to from nuclear power plants andindustrial and medical facilities that arelicensed to use nuclear materials. NRC alsoconducts research, testing, and training pro-grams, and has the authority to regulatelow-level and high-level radioactive wastefacilities. NRC enforces its own standards aswell as some of EPA’s standards for protect-ing the public from radiation.

Department of Energy (DOE)

DOE’s important responsibilities for protect-ing the public from radiation include:• Issuing standards and guidelines and

enforcing some of EPA’s radiation stan-dards for protecting workers and the pub-lic at DOE facilities.

• Developing the disposal system for spentnuclear fuel from the nation’s civiliannuclear power plants. (See Sites andMethods of Waste Disposal, Chapter 4,page 46.) This activity is funded com-pletely by a tax paid by the users ofnuclear-generated electricity.

• Managing the cleanup and disposal ofradioactive materials that resulted fromnuclear weapons production at federallyowned facilities during the Cold War.(See Nuclear Weapons Waste, Chapter 4,page 51.)

• Cooperating with state governments, trib-al governments, the public, and privateindustry to clean up other locationsaround the United States that were con-taminated with radiation as a result ofgovernment programs.

• Providing technical advice and assistanceto states and the private sector for manag-ing and disposing of low-level radioactivewaste.


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Environmental Protection Agency(EPA)Since its establishment in 1970 as part ofthe executive branch of the federal govern-ment, EPA has been responsible for protect-ing the public health and the environmentfrom avoidable exposures to radiation. Incarrying out this mission, EPA:• Issues standards and guidance to limit

radiation exposures and conducts anational monitoring program to keeptrack of radiation levels in the environ-ment. (See Monitoring Radiation Levelsin the Environment, this Chapter 4, page62.)

• Works with industry, the states, and othergovernment agencies to inform the publicabout radiation risks and to promoteactions that reduce human exposure.

• Assesses radiation effects on people andthe environment, studies radiation meas-urement and control, and provides tech-nical assistance to states and other federalagencies.

• Administers the National Radon Programand evaluates new and developing radia-tion control and cleanup technologies.

• Provides technical assistance and supportfor cleaning up radioactively contaminat-ed sites.

EPA sets standards for the management anddisposal of radioactive wastes and guidelinesrelating to control of radiation exposureunder the Atomic Energy Act, the CleanAir Act, and other legislation. (Table 5)The legislation describes the result EPAmust produce (for example, “protect thepublic health” with an “ample margin ofsafety”). EPA must determine what levels orlimits are considered protective and specifymeasures or processes for putting thesemeasures in place. In 1989, for example,under the Clean Air Act, EPA publishedstandards limiting emissions of radioactivematerials from all federal and industrialfacilities. (See Controlling Radiation in theAir, Chapter 4, page 59.)

Department of Defense (DOD)

DOD is in charge of the safe handling andstorage of nuclear weapons and other mili-tary uses of nuclear energy under its custody.These uses include fueling nuclear-poweredships and research reactors, cleaning up anddecommissioning military bases, and prac-ticing nuclear medicine. (DOE remainsresponsible for the safe handling of radioac-tive material at DOE defense weapons production facilities.)

Department of Transportation(DOT)

DOT, in cooperation with NRC and theStates, governs the packaging and transportof radioactive materials. (See TransportingRadioactive Waste, Chapter 4, page 55.)The department regulates both the carriersand the drivers who transport these materi-als. DOT’s Research and Special ProgramsAdministration (RSPA) is responsible forissuing hazardous materials regulations forradioactive materials that are compatiblewith the regulations of the InternationalAtomic Energy Agency (IAEA). (See Roleof International Organizations in thisChapter, page 70.)

Department of Health and HumanServices (HHS)

The Food and Drug Administration (FDA)carries out HHS radiation responsibilities.FDA’s Center for Devices and RadiologicalHealth sets standards for X-ray machines,microwave ovens, and other electronicproducts to ensure that the radiation theseitems produce does not endanger humanhealth. FDA, in conjunction with theDepartment of Agriculture, also regulatesthe use of radiation on food. (See FoodIrradiation, Chapter 3, page 29.)

Occupational Safety and HealthAdministration (OSHA)

OSHA, part of the Department of Labor,has the mission of saving lives, preventinginjuries, and protecting the health ofAmerica’s workers. Under of the authority


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fromRadiation?

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LocalGovernment

Functions

of the Occupational Safety and Health Actof 1970, OSHA develops and enforces regu-lations to protect workers who are not cov-ered by other agencies from radiation expo-sure.

The National Academy of Sciences(NAS)

While not part of the federal government,NAS frequently conducts studies at thegovernment’s request and advises federalagencies on scientific and technical aspectsof radiation issues. For years, NAS has beenheavily involved in the government’s searchfor a solution to the high-level andtransuranic nuclear waste disposal problem.The NAS’s Committee on the BiologicalEffects of Ionizing Radiation (BEIRCommittee) and its predecessors have beenissuing influential reports on radiation andits health effects for the past 35 years.

National Council on RadiationProtection and Measurements(NCRP)

NCRP is a nonprofit corporation charteredby Congress in 1964 to study the scientificand technical aspects of radiation protec-tion. With NRC and EPA, NCRP recom-mends radiation standards that help formthe basis for federal, state, and local regula-tions to protect the public health and theenvironment from radiation hazards.NCRP’s members, chosen on the basis oftheir scientific expertise, come from univer-sities, medical centers, national and privatelaboratories, and industry. NCRP’s interna-tional counterpart is the InternationalCommission on Radiological Protection.(See ICRP in this Chapter, page 70.)

Federal, State, and LocalGovernment FunctionsResponding to Emergencies

The 1979 accident at Three Mile Islandnuclear power plant changed the approachto responding to nuclear accidents in theU.S. (See Accidental Releases, Chapter 3,page 39.) As a result of the accident, NRC

requires all domestic nuclear power plantsto develop and test emergency plans.

A number of federal and state agencies havevarious roles in preparing for and respond-ing to radiological emergencies:

• State and local emergency governmentresponse agencies have primary responsi-bility for immediate response and publicprotection in a radiological emergency.

• Seventeen U.S. government agenciescooperated in developing the FederalRadiological Emergency Response Plan.This plan provides for coordinated federalassistance to state and local governmentsdealing with the risks posed by accidentalreleases of radioactive material.Depending on the situation, EPA, NRC,DOD, NASA, DOE, HHS, the FederalEmergency Management Agency, and/orthe Department of Agriculture may playsignificant roles in any federal response.

• EPA’s Radiological Emergency ResponseTeam (RERT) provides quick responseand support for incidents involving radio-logical hazards. The RERT can monitorand assess radioactivity in the environ-ment from an accident to define theextent of exposure.

• EPA determines the exposure levels atwhich protective actions, such as stayingindoors or evacuating the area, should beconsidered in case of a release or poten-tial release of radioactive material to theenvironment.

• DOE’s Federal Radiological Monitoringand Assessment Center coordinates theprimary federal equipment and materialfor environmental and personnel moni-toring immediately following an emer-gency.

Setting Standards

Radiation is classified as a class A carcino-gen. This means there is specific scientificevidence proving that radiation can causecancer. EPA sets radiation protection stan-dards so that the maximum allowable dose

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to a member of the public is protective ofhuman health and the environment. (Forthe purpose of setting radiation standards,protective means not adding significantly tothe average risk of developing cancer.)

When setting standards, EPA considersadditional factors, including:

• The benefits provided by the source ofradiation

• The size of the dose received

• The frequency of exposure

• The feasibility and cost of avoiding exposure

EPA also considers public comments beforefinalizing its standards.

NCRP and The International Commissionon Radiological Protection also have a rolein recommending standards within theUnited States. (See Responsible FederalAgencies in this Chapter, p. 65.) The rec-ommendations issued by these organizationsprovide the scientific basis for radiation pro-tection efforts throughout the country.Governmental organizations, includingNRC, the U.S. Public Health Service, EPA,and state governments, use recommenda-tions from ICRP and NCRP as the scientif-ic basis for their protection activities.

EPA sets radiation standards that minimizethe public’s exposure to various sources ofradioactivity, including both manmade and,in some instances, natural sources. (SeeNatural Sources, Chapter 2, page 18.) Forexample:

• EPA’s drinking water standards controlthe public’s exposure to both natural andman-made sources of radiation. Waterdepartments and other suppliers of drink-ing water must comply with limits on theradionuclide content in public water supplies.

• EPA’s regulations for high-level radioac-tive waste disposal limit the exposure ofthe public from such facilities to no morethan 15 millirems per year.

• For abandoned uranium mines, EPA lim-

its the concentration of naturally occur-ring radium and thorium left behind atthe site to no more than five picocuriesper gram in the upper 15 centimeters ofsoil.

In enforcing EPA’s exposure standards forthe nuclear industry, NRC limits the air andwater emissions of radionuclides fromnuclear reactors to levels that would exposeno member of the public to more than 25millirems of radiation per year.

For occupational exposures at nuclearplants, NRC limits the sum of both internaland external doses to workers to 5,000 mil-lirem per year. Actual annual occupationalexposures in the U.S. nuclear energy indus-try average much less than 5,000 millirem.The average worker dose in the U.S.nuclear energy industry in 1995 was about160 millirem, less than 5 percent of theNRC limit.

EPA and NRC co-chair the InteragencySteering Committee on RadiationStandards, which includes representatives ofthe DOE, DOD, and other federal agencies.The committee works to foster early resolu-tion and coordination of regulatory issuesassociated with radiation standards.

Issuing Guidance

When radiation hazards exist but legallybinding regulations are inappropriate, EPAissues guidance, recommends action levels,and/or undertakes public education effortsthat will help protect the public from exces-sive exposures. For example:

• EPA’s radon program recommends anaction level of 4 pCi/L. EPA recom-mends, but does not require, that home-owners reduce radon levels below theaction level in their homes (see TheHealth Effects of Radon, Chapter 3, page37.)

• EPA’s radon educational efforts helpreduce exposure to natural radiation.

• EPA’s SunWise school program is a com-prehensive health and science relatedprogram designed to educate children


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about overexposure to ultraviolet radia-tion from the sun and how it can affecttheir health in the future.

• EPA’s 1987 guidelines help federal agen-cies to develop radiation exposure stan-dards for workers. These standards recom-mend the maximum amount of radiationthat workers in nuclear power, medicine,industry, mining, and waste managementcan safely receive.

Conducting Site Cleanup

Government agencies and private compa-nies alike are required by law to clean upany hazardous and radioactive substancesthat could endanger public health and wel-fare and the environment. CERCLA givesEPA the authority to determine the degreeof public hazard posed by contaminatedsites. EPA places the most serious problemsites on the Superfund National PrioritiesList (NPL) for expedited study and cleanup.For sites on the NPL, EPA works closelywith the affected states, with input from thepublic, to develop and monitor site assess-ment and cleanup schedules.

EPA also supports efforts to clean up themany non-NPL sites in the United Statescontaminated with radioactive material,including those contaminated with mixedwaste—a combination of radioactive andhazardous chemical waste (See MixedWaste, Chapter 4, page 48.)

Other Roles in ManagingRadiationRole of the States and NativeAmerican Tribes

States have additional responsibilities forprotecting the public and the environmentthat go beyond responding to radiologicalemergencies. Both EPA and NRC areauthorized to delegate some of their regula-tory authority over radioactive materials tothe states.

• EPA can authorize states to regulate haz-ardous wastes under the RCRA.

• NRC can delegate regulation of radioac-

tive materials from facilities (exceptnuclear power plants) within their juris-dictions to states, called AgreementStates, that have reached an agreementwith the NRC under the Atomic EnergyAct of 1954.

• NRC may also delegate to AgreementStates regulation of low-level waste dis-posal facilities under the Low-LevelRadioactive Waste Policy Act of 1980.The law makes the states responsible,either individually or in groups calledcompacts, for ensuring adequate disposalcapacity for the low-level radioactivewaste generated within their borders.

• DOE must consult the state if it is consid-ering building a high-level waste storageor disposal facility within state borders,under the Nuclear Waste Policy Act of1982. If a state objects to the siting ofsuch a facility, both houses of Congressmust vote to overturn the state’s veto.

• Native American tribes that may beaffected by a potential waste disposal siteare also guaranteed the same rights asaffected states under the 1982 Act. In theearly 1990s, several tribes actively partici-pated in feasibility studies as potentialhosts to a proposed interim storage facili-ty for spent nuclear fuel until a perma-nent repository is built. (See Sites andMethods of Waste Disposal, Chapter 4,page 46.) Tribes with treaty claims tolands currently occupied by DOE nuclearweapons facilities, such as the HanfordSite in Washington, are participating inthe decontamination and cleanup ofthose territories. Some tribes are voicingconcerns about additional exposure fromthe transport of nuclear waste.

• States and tribes also play a role, withNRC and DOT, in regulating the trans-portation of radioactive materials withintheir borders. (See TransportingRadioactive Waste, Chapter 4, page 55.)and in preparing for accidents or emer-gencies involving nuclear waste ship-ments.

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• For TENORM, states are developing avariety of standards and guidances. Manystates have developed regulations for themanagement and disposal of radium-con-taminated pipe scale from the oil and gasindustry. Some states have issued guid-ance to address the disposal of sludge andresidues resulting from the treatment ofwater at public water supplies.

• OSHA delegates some worker protectionresponsibilities to the states.

• Most states regulate the specifications forX-ray equipment.

Role of International Organizations

National governments have primary respon-sibility for ensuring the safety of nuclearoperations within their borders. As theChernobyl accident dramatically demon-strated, however, radiation from nuclearaccidents can spread rapidly across interna-tional boundaries. (See AccidentalReleases, Chapter 3, page 39.)

Several international organizations havebeen formed to help establish and ensurecompliance with worldwide radiation pro-tection standards.

• The International Commission onRadiological Protection (ICRP), estab-lished in 1928, provides worldwide rec-ommendations and guidance on radiationprotection. Its members come from 20countries and include scientists, physi-cians, and engineers. While ICRP has noformal power to impose its proposals onanyone, legislation in most countriesadheres closely to ICRP recommenda-tions. Congress chartered in 1964 theU.S. counterpart to the ICRP, theNational Council on RadiationProtection and Measurements (NCRP).

• The International Atomic EnergyAgency (IAEA) is a 131-member inde-pendent organization operating under theprotection of the United Nations. IAEAwas organized in 1956 to promote peace-ful uses of nuclear energy. It appliesnuclear safety and radiation protectionstandards to its own operations and to

activities that make use of IAEA materi-als, equipment, facilities, and services.Countries that receive IAEA assistanceare required to observe health and safetymeasures prescribed by the agency.

• The Nuclear Energy Agency (NEA) isan arm of the Organization for EconomicCooperation and Development (OECD).NEA is a 23-member body that promotesthe exchange of information on nuclearwaste issues; conducts and sponsors inter-national research and development proj-ects; and coordinates research, site inves-tigations, and underground demonstrationprojects by its members. NEA also recom-mends nuclear safety standards to OECDmember nations.

• The International Commission onRadiological Units and Measurements(ICRU) recommends the units used indesignating radiation protection levels.The ICRU was created in 1925.

• The United Nations ScientificCommittee on the Effects of AtomicRadiation (UNSCEAR) was establishedin 1955 to evaluate doses, effects, andrisks from ionizing radiation on a globalscale. UNSCEAR is one of the interna-tional organizations studying theHiroshima and Nagasaki survivors. (SeeStudying Radiation’s Effects on Humans,Chapter 3, page 33.) Based on its studies,UNSCEAR makes risk estimates that areused by the IAEA, the NEA, and otherorganizations to set radiation exposurestandards.

Your Role as a Citizen

Since we are constantly exposed to manydifferent sources of background radiationthroughout our lives, there is no way toreduce our exposure to zero. Hence, we can-not guarantee that we are completely safefrom the possible effects of radiation. As istrue for many other aspects of life, the veryfact of living means we have to accept acertain amount of risk from the radiation allaround us.


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As concerned citizens, the key question weneed to ask and try to help answer is:

How much exposure to radiationbeyond the normal levels of uncontrol-lable natural radiation should societytolerate in order to balance the risksand the benefits of radiation?

Public participation can play a significantrole in the way the government managesrisk, including the risk of exposure to radia-tion. In a democracy, when citizens speakup at public hearings, write to their electedrepresentatives and regulatory agencies,march on picket lines, and file lawsuits,their opinions count. The voices of citizensinfluence the debate that helps determinewhat laws and regulations are written,where and when facilities are built, andwhat levels of releases and exposure will bepermitted by the government.

In fact, many government agencies areincreasingly inviting this kind of public par-ticipation—called stakeholder involve-ment—in their decision-making process.They are doing so by

• Publishing scientific and regulatory infor-mation on public issues, both in hardcopy and on their World Wide Web sites

• Holding public meetings and hearingsand teleconferences

• Encouraging citizens to submit writtencomments on proposed policies and programs

The goal of these outreach efforts is toinvolve citizens more directly in determin-ing the appropriate balance between, forexample, sustaining our nations economicstrength and other social values, such asmaintaining environmental quality.

Ultimately, we must rely on our elected offi-cials and the regulators who are responsiblefor enforcing their decisions to find the bestbalance of social, political, and scientificfactors for the benefit of society as a whole.Citizens can help them do their jobs moreeffectively by learning about and doing

their best to understand the environmentaland other consequences of technologicalchange, including the benefits and risksassociated with radiation in all its forms.The more we know, the better equipped wewill be to help ensure that society developsand uses radiation wisely.

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AAppendix A: Glossary of Radiation Terms


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Acute Exposure: A single exposure to asubstance which results in biological harmor death. Usually characterized by a briefexposure lasting no more than a day, ascompared to longer, continuing exposureover a period of time (chronic exposure).

Agreement State: A State that has signedan agreement with the Nuclear RegulatoryCommission allowing the State to regulatethe use of by-product radioactive materialwithin that State.

ALARA: Acronym for “As Low AsReasonably Achievable.” It means makingevery reasonable effort to maintain exposuresto ionizing radiation as far below the dose lim-its as practical, consistent with the purpose forwhich the licensed activity is undertaken, tak-ing into account the state of technology, theeconomics of improvements in relation tostate of technology and in relation to benefitsto the public health and safety, and other soci-etal and socioeconomic considerations.

Alpha particle: A positively charged parti-cle ejected spontaneously from the nuclei ofsome radioactive elements. It has low pene-trating power and a short range (a few cen-timeters in air). The most energetic alphaparticle will generally fail to penetrate thedead layers of cells covering the skin andcan be easily stopped by a sheet of paper.Alpha particles are hazardous when analpha-emitting isotope is inside the body.

Atom: The smallest unit of an elementthat cannot be divided or broken up bychemical means. It consists of a central coreof protons and neutrons (except hydrogenwhich has no neutrons), called the nucleus.

Electrons revolve in orbits in the region sur-rounding the nucleus.

Atomic energy: Energy released in nuclearreactions. Of particular interest is the ener-gy released when a neutron initiates thebreaking up of an atom's nucleus into small-er pieces (fission), or when two nuclei arejoined together under millions of degrees ofheat (fusion). It is more correctly callednuclear energy.

Atomic Energy Commission: Federalagency created in 1946 to manage thedevelopment, use, and control of nuclearenergy for military and civilian applications.Abolished by the Energy ReorganizationAct of 1974 and succeeded by the EnergyResearch and Development Administration(now part of the U. S. Department ofEnergy) and the U. S. Nuclear RegulatoryCommission.

Atoms for Peace: President Eisenhower's1954 initiative to allow the peaceful uses ofatomic energy to be available to othernations.

Background radiation: Radiation from cos-mic sources and terrestrial sources, includ-ing radon. It does not include radiationfrom source or byproduct nuclear materialsregulated by the Nuclear RegulatoryCommission. The average individual expo-sure from background radiation is about 300millrems per year.

Beta particle: A charged particle emittedfrom a nucleus during radioactive decay,with a mass equal to 1/1837 that of a pro-ton. A negatively charged beta particle isidentical to an electron. A positively

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charged beta particle is called a positron.Large amounts of beta radiation may causeskin burns, and beta emitters are harmful ifthey enter the body. Beta particles may bestopped by thin sheets of metal or plasitc.

Biological effectiveness factor: Neutronsand alpha particles do more harm per unitdose than photons or beta particles. Anexperimentally determined value for thisdifference is referred to as the relative bio-logical effectiveness (RBE) and is mostlyrestricted to uses in the field of radiobiology.Each species tested, each target organ with-in that species, and each radionuclide cho-sen might give a different RBE. Forhumans, a conservative upper limit of theRBE, called the quality factor (Q) or theradiation weighting factor (WR), is used todetermine the dose equivalent.

Carcinogen: A cancer-causing substance.

Chain reaction: A reaction that initiatesits own repetition. In a fission chain reac-tion, a fissionable nucleus absorbs a neutronand fissions spontaneously, releasing addi-tional neutrons. These, in turn, can beabsorbed by other fissionable nuclei, releas-ing still more neutrons. A fission chainreaction is self-sustaining when the numberof neutrons released in a given time equalsor exceeds the number of neutrons lost byabsorption in nonfissionable material or byescape from the system.

Charged particle: An ion. An elementaryparticle carrying a positive or negative elec-tric charge.

Chronic exposure: Exposure to a substanceover a long period of time resulting inadverse health effects.

Compact: A group of two or more Statesformed to dispose of low-level radioactivewaste on a regional basis. Forty-four Stateshave formed ten compacts.

Contamination: The deposition of unwant-ed radioactive material on the surfaces ofstructures, areas, objects, or people. It mayalso be airborne, external, or internal(inside components or people).

Cooling tower: A heat exchanger designed

to aid in the cooling of water that isused tocool exhaust steam exiting the turbines of apower plant. Cooling towers transferexhaust heat into the air instead of into abody of water.

Core: The central portion of a nuclearreactor containing the fuel elements, mod-erator, neutron poisons, and support struc-tures.

Core melt accident: An event or sequenceof events that result in the melting of partof the fuel in a nuclear reactor core.

Cosmic radiation: Ionizing radiation, bothparticulate and electromagnetic, originatingin outer space.

Criticality: A term used in reactor physicsto describe the state when the number ofneutrons released by fission is exactly bal-anced by the neutrons being absorbed andescaping the reactor core. A reactor is saidto be “critical” when it achieves a self-sus-taining nuclear chain reaction, as when thereactor is operating.

Cumulative dose: The total dose to anindividual resulting from repeated exposuresof ionizing radiation to the same portion ofthe body, or to the whole body, over a peri-od of time.

Curie (Ci): The basic unit used to describethe intensity of radioactivity in a sample ofmaterial. The curie is equal to 37 billion (3X 1010) disintegrations per second, which isapproximately the activity of 1 gram of radi-um. A curie is also a quantity of anyradionuclide that decays at a rate of 37 bil-lion disintegrations per second. It is namedfor Marie and Pierre Curie, who discoveredradium in 1898.

Decay, radioactive: The decrease in theamount of any radioactive material with thepassage of time due to the spontaneousemission of radiation from the atomicnuclei (either alpha or beta particles, oftenaccompanied by gamma radiation).

Decommission: The process of closingdown a nuclear facility and reducingradioactivity at the facility to a level safe forunrestricted use.

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Decontamination: The reduction orremoval of contaminated radioactive mate-rial from a structure, area, object, or person.Decontamination may be accomplished by:(1) treating the surface to remove ordecrease the contamination, (2) letting thematerial stand so that the radioactivity isdecreased as a result of natural radioactivedecay, or (3) covering the contamination tolimit the radiation emitted.

Dose, absorbed: Represents the amount ofenergy absorbed from the radiation in agram of any material. It is expressed numer-ically in rads.

Dose equivalent (also called biologicaldose): is a measure of the biological damageto living tissue from the radiation exposure.It takes into account the type of radiationand the absorbed dose. For example whenconsidering beta, X-ray, and gamma rayradiation, the equivalent dose (expressed inrems) is equal to the absorbed dose(expressed in rads). For alpha radiation, theequivalent dose is assumed to be twentytimes the absorbed dose. It is expressednumerically in rem.

Dose rate: The ionizing radiation dosedelivered per unit time. For example, remper hour.

Dosimeter: A small portable instrument(such as a film badge, thermoluminescent,or pocket dosimeter) for measuring andrecording the total accumulated personneldose of ionizing radiation.

Electromagnetic radiation: Radiation con-sisting of electric and magnetic waves. Atraveling wave motion resulting fromchanging electric or magnetic fields. Itranges from X-rays (and gamma rays) withshort wavelength, through the ultraviolet,visible, and infrared regions, to radar andradio waves with relatively long wavelength.

Electron: An elementary particle with anegative charge and a mass 1/1,837 that ofthe proton. Electrons surround the positive-ly charged nucleus and determine thechemical properties of the atom.

Element: One of the 103 known chemicalsubstances that cannot be broken down fur-ther without changing its chemical proper-ties. Some examples include, hydrogen,nitrogen, gold, lead, and uranium.

Entomb: A method of decommissioning anuclear facility in which radioactive con-taminants are encased in long-lived materi-al, such as concrete. The entombmentstructure is maintained and monitored untilthe radioactivity decays to a level allowingdecommissioning and ultimately, safe unre-stricted use of the property.

Epidemiological studies: Studies of the dis-tribution of disease and other health issuesas related to age, sex, race, ethnicity, occu-pation, economic status, or other factors.

Fallout, nuclear: The slow decent ofminute particles of radioactive debris in theatmosphere following a nuclear explosion.

Film badge: Photographic film used formeasurement of ionizing radiation exposurefor personnel monitoring purposes. The filmbadge may contain two or three films of dif-fering sensitivities, and it may also containa filter that shields part of the film from cer-tain types of radiation.

Fissile material: Although sometimes usedas a synonym for fissionable material, thisterm has acquired a more restricted mean-ing. Namely, any material fissionable bythermal (slow) neutrons. The three primaryfissile materials are uranium-233, uranium-235, and plutonium-239.

Fission (fissioning): The splitting of anucleus into at least two other nuclei andthe release of a relatively large amount ofenergy. Two or three neutrons are usuallyreleased during this type of transformation.Fissioning is also referred to as burning.

Fuel cycle: The series of steps involved insupplying and managing fuel used in nuclearpower reactors. It can include mining,milling, isotopic enrichment, fabrication offuel elements, use in a reactor, reenrich-ment of the fuel material, refabrication intonew fuel elements, and waste disposal.

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Fuel rod: A long, slender tube that holdsfissionable material and managing (fuel)used in nuclear reactor use. Fuel rods areassembled into bundles called fuel elementsor fuel assemblies, which are loaded individ-ually into the reactor core.

Fusion: A reaction in which at least oneheavier, more stable nucleus is producedfrom two lighter, less stable nuclei.Reactions of this type are responsible forenormous release of energy, as in the energyof stars, for example.

Gamma radiation: High-energy, shortwavelength, electromagnetic radiationemitted from the nucleus. Gamma radiationfrequently accompanies alpha and betaemissions. Gamma rays are very penetratingand are best stopped or shielded by densematerials, such as lead. Gamma rays aresimilar to X-rays

Geiger counter (or Geiger-Mueller count-er): A radiation detection and measuringinstrument. It consists of a gas-filled tubecontaining electrodes, between which thereis an electrical voltage, but no current flow-ing. When ionizing radiation passes throughthe tube, a short, intense pulse of currentpasses from the negative electrode to thepositive electrode and is measured or count-ed. The number of pulses per second meas-ures the intensity of the radiation field. It isthe most commonly used portable radiationinstrument.

Half-life: The time in which one half ofthe atoms of a particular radioactive sub-stance decay into another nuclear form.Half-lives vary from millionths of a secondto billions of years.

Hazardous Waste: By-products that canpose a substantial or potential hazard tohuman health or the environment whenimproperly managed. Hazardous waste hasat least one of four characteristics—ignitable, corrosive, reactive, or toxic, or islisted in regulations as hazardous.

High-level waste: Highly radioactivematerial resulting from the reprocessing ofspent nuclear fuel and other highly radioac-

tive material that, under current law, mustbe permanently isolated.

Ion: (1) An atom that has too many or toofew electrons, causing it to have an electri-cal charge, and therefore, be chemicallyactive. (2) An electron that is not associat-ed (in orbit) with a nucleus.

Ionization: The process of adding one ormore electrons to, or removing one or moreelectrons from, atoms or molecules, therebycreating ions. High temperatures, electricaldischarges, or nuclear radiation can causeionization.

Ionizing radiation: Any radiation capableof displacing electrons from atoms or mole-cules, thereby producing ions. Some exam-ples are alpha, beta, gamma, and X-rays.High doses of ionizing radiation may pro-duce severe skin or tissue damage.

Irradiation: Exposure to radiation

Isotope: One of two or more atoms withthe same number of protons, but differentnumbers of neutrons in their nuclei. Forexample, carbon-12, carbon-13, and car-bon-14 are isotopes of the element carbon,the numbers denote the approximate atom-ic weights. Isotopes have very nearly thesame chemical properties, but often differ-ent physical properties (for example, car-bon-12 and -13 are stable, carbon-14 isradioactive).

Linear- no-threshold-hypothesis: The the-ory that the number of cancers and othereffects of exposure to low levels of radiationare proportionate to the number of cancersfrom exposure to high levels of radiation.The precise effects are uncertain because itis very difficult to directly measure theeffects of low levels of radiation.

Manhatten Project: The U.S. governmentprogram to develop the first atomicweapons during World War II.

Mill-tailings: Naturally radioactive residuefrom the processing of uranium ore.Although the milling process recovers about93 percent of the uranium, the residues, ortailings, contain several naturally-occurring

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radioactive elements, including uranium,thorium, radium, polonium, and radon.

Molecule: A group of atoms held togetherby chemical forces. A molecule is the small-est unit of a compound that can exist byitself and retain all of its chemical properties.

Neutron: An uncharged elementary parti-cle with a mass slightly greater than that ofthe proton, and found in the nucleus ofevery atom heavier than hydrogen.

Non-ionizing radiation: Radiation that haslower energy levels and longer wavelengths.It is not strong enough to affect the struc-ture of atoms it contacts, but it does heattissue and can cause harmful biologicaleffects. Examples include radio waves,microwaves, visible light, and infrared froma heat lamp.

NARM/NORM: Naturally Occurring andAccelerator-Produced Radioactive Materials(NARM) include by-products of petroleumproduction, coal ash, phosphate fertilizerproduction, drinking water treatment, andother industrial processes. NORM is a sub-set of NARM and includes everything inNARM except accelator-produced materi-als. The federal government has not devel-oped a comprehensive policy forNORM/NARM disposal.

Nuclear energy: The heat energy producedby the process of nuclear reaction (fission orfusion) within a nuclear reactor or byradioactive decay.

Nuclear power plant: An electrical gener-ating facility using a nuclear reactor as itspower (heat) source. The coolant thatremoves heat from the reactor core is nor-mally used to boil water. The steam pro-duced by the boiling water drives turbinesthat rotate electrical generators.

Nuclear tracers: Radioisotopes that givedoctors the ability to “look” inside the bodyand observe soft tissues and organs, in amanner similar to the way X-rays provideimages of bones. A radioactive tracer ischemically attached to a compound thatwill concentrate naturally in an organ or

tissue so that a picture can be taken.

Nucleus: The small, central, positivelycharged region of an atom that carries theatom's nuclei. All atomic nuclei containboth protons and neutrons (except for ordi-nary hydrogen, which has a single proton).The number of protons determines the totalpositive charge, or atomic number.

Nuclide: A general term referring to allknown isotopes, both stable (279) andunstable (about 5,000), of the chemical ele-ments.

Photon: A quantum (or packet) of energyemitted in the form of electromagnetic radi-ation. Gamma rays and X-rays are examplesof photons.

Picocurie: One trillionth of a curie.

Plutonium: A very heavy element formedwhen uranium-238 absorbs neutrons. Likeuranium, it has two principal isotopes thatare fissile.

Poison, neutron: In reactor physics, amaterial other than fissionable material, inthe vicinity of the reactor core that willabsorb neutrons. The addition of poisons,such as control rods or boron, into the reac-tor is said to be an addition of negativereactivity.

Positron: Particle equal in mass, but oppo-site in charge, to the electron (a positiveelectron).

Power reactor: A reactor designed to pro-duce heat for electric generation, as distin-guished from reactors used for research, forproducing radiation or fissionable materials,or for reactor component testing.

Proton: An elementary nuclear particlewith a positive electric charge located inthe nucleus of an atom.

Quality factor: The factor by which theabsorbed dose (rad) is multiplied to obtain aquantity that expresses, on a common scalefor all ionizing radiation, the biologicaldamage (rem) to an exposed individual. It isused because some types of radiation, suchas alpha particles, are more biologicallydamaging internally than other types.

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Rad: The unit of absorbed dose, which isthe amount of energy from any type of ion-izing radiation (e.g., alpha, beta, gamma,etc.) deposited in any medium (e.g., water,tissue, air). A dose of one rad means theabsorption of 100 ergs (a small but measura-ble amount of energy) per gram of absorbingtissue.

Radiation: Energy in the form of waves orparticles sent out over a distance.

Radiation sickness (or syndrome): Thecomplex of symptoms characterizing the dis-ease known as radiation injury, resultingfrom excessive exposure (greater than 200rads) of the whole body (or large part) toionizing radiation. The earliest of thesesymptoms are nausea, fatigue, vomiting, anddiarrhea, which may be followed by loss ofhair, hemorrhage, inflammation of themouth and throat, and general loss of ener-gy. In severe cases, where the radiationexposure has been approximately 1,000 rador more, death may occur within two tofour weeks.

Radiation standards: Exposure limits, per-missible concentrations, rules for safe han-dling, regulations for transportation, andregulations controlling the use of radiationand radioactive material.

Radiation warning symbol: An officiallyprescribed symbol (a magenta or black tre-foil) on a yellow background that must bedisplayed where certain quantities ofradioactive materials are present or wherecertain doses of radiation could be received.

Radioactive contamination: Deposition ofradioactive material in any place where itmay harm persons, equipment, or the envi-ronment.

Radioactivity: The emission of radiation,generally alpha or beta particles, oftenaccompanied by gamma rays, from thenucleus of an unstable isotope. Also, therate at which radioactive material emitsradiation.

Radioisotope: An unstable isotope of anelement that decays or disintegrates sponta-neously, emitting radiation. Approximately

5,000 natural and artificial radioisotopeshave been identified.

Radionuclide: A radioactive nuclide. Anunstable isotope of an element that decaysor disintegrates spontaneously, emittingradiation.

Radiology: The branch of medicine deal-ing with the diagnostic and therapeuticapplications of radiation, including X-raysand radioisotopes.

Radon (Rn): A radioactive element that isone of the heaviest gases known. Its atomicnumber is 86. It is found naturally in soiland rocks and is formed by the radioactivedecay of radium.

Reactor, nuclear: A device in whichnuclear fission may be sustained and con-trolled in a self-supporting nuclear reaction.There are different designs.

Recycling: The reuse of slightly contami-nated materials.

Rem: The unit of measurement of doseequivalent. The rem value takes intoaccount both the amount, or dose, of radia-tion and the biological effect of the specifictype of radiation. Rem equals the absorbeddose multiplied by the quality factor. (100rem = 1 sievert)

Reprocessing: The mechanical and chemi-cal process of separating out usable products(like uranium and plutonium) from spent ordepleted reactor fuel then re-enriching andre-fabricating them inor new fuel elements.

Risk: In many health fields, risk means theprobability of incurring injury, disease, ordeath. Risk can be expressed as a value thatranges from zero (no injury or harm willoccur) to one hundred percent (harm orinjury will definitely occur).

Risk assessment: Qualitative and quanti-tative evaluation of the risk posed to humanhealth and/or the environment by the actu-al or potential presence of hazards.

Roentgen: A unit of exposure to ionizingradiation. It is the amount of gamma or X-rays required to produce ions resulting in a

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charge of 0.000258 coulombs/kilogram ofair under standard conditions.

Somatic effects of radiation: Effects ofradiation limited to the exposed individual,as distinguished from genetic effects, whichmay also affect subsequent unexposed gen-erations.

Spent (depleted) fuel: Nuclear reactor fuelthat has been used to the extent that it canno longer effectively sustain a chain reac-tion.

Subatomic particles: The matter thatmakes up atoms. It includes particles suchas neutrons, protons, electrons, and manymore.

Superfund: The program operated underthe authority of the ComprehensiveEnvironmental Response, Compensation,and Liability Act (CERCLA) and theSuperfund Amendments andReauthorization Act (SARA) that fundsand carries out EPA hazardous waste emer-gency and long-term removal and remedialactivities.

Terrestrial radiation: Radiation that isemitted by naturally occurring radioactivematerials in the earth, such as uranium,thorium, and radon.

Thermoluminescent dosimeter: A smalldevice used to measure radiation dose bymeasuring the amount of visible light emit-ted from a crystal in the detector. Theamount of light emitted is proportional tothe radiation dose received.

Thermonuclear: An adjective referring tothe process in which very high temperaturesare used to bring about the fusion of lightnuclei, such as those of the hydrogen iso-topes deuterium and tritium, with theaccompanying liberation of energy.

Ultraviolet radiation: Radiation of a wave-length between the shortest visible violetrays and low energy X-rays.

Unstable isotope: A radioactive isotope.

Uranium: The heaviest element normallyfound in nature. The principal fuel material

used in today's nuclear reactors is the fissileisotope uranium-235.

Uranium Mill Tailings: See Mill Tailings.

Waste, radioactive: Solid, liquid, andgaseous materials from nuclear operations orTENORM activities that are radioactive orbecome radioactive and for which there isno further use.

Whole body exposure: An exposure of thebody to radiation, in which the entire body,rather than an isolated part, is irradiated.

X-rays: One type of electromagnetic radia-tion which arises as electrons are deflectedfrom their original paths or inner orbitalelectrons change their energy levels aroundthe atomic nucleus. Like gamma rays, X-rays require more shielding to reduce theirintensity than do beta or alpha particles.

Sources:• Glossary of Nuclear Terms, Nuclear

Regulatory Commission, • http://www.nrc.gov/NRC/EDUCATE/

GLOSSARY/index.html#N• Fact Sheet, Health Physics Society,

http://www.hps.org/publicinformation/radfactsheets.cfm

• Glossary of Nuclear Terms, http://ie.lbl.gov/education/glossary/glossaryf.htm, Lawrence Berkely Laboratory

• Glossary of Nuclear Terms, Frontline, PBS, http://www.pbs.org/wgbh/pages/frontline/shows/reaction/etc/terms.html

• Terms of Environment, Environmental Protection Agency, http://www.epa.gov/OCEPAterms/intro.htm.

Appendix


Terms

BLANK

BAppendix B: List of Acronyms


Appendix

List ofAcronyms

81

AC alternating currentAEC Atomic Energy CommissionALARA as low as reasonably

achievableBEIR U.S. Committee on

Biological Effects of Ionizing Radiation

CERCLA Comprehensive Environmental Response, Compensation, and LiabilityAct

CAA Clean Air ActDoD Department of DefenseDOE Department of EnergyDOT Department of

TransportationEMF electric and magnetic fieldsEPA U.S. Environmental

Protection AgencyFDA Food and Drug

AdministrationIAEA International Atomic Energy

AgencyICRP International Commission

on Radiological ProtectionICRU International Commission of

Radiological Units and Measurements

MRI magnetic resonance imagingNARM naturally occurring and

accelerator-produced radioactive materials

NAS National Academy of Sciences

NCI National Cancer InstituteNCRP National Council on

Radiation Protection and Measurements

NEA Nuclear Energy Agency of

the Organization for Economic Cooperation and Development

NEI Nuclear Energy InstituteNIEHS National Institute of

Environmental Health Sciences

NIH National Institutes of HealthNIMBY not in my backyardNORM naturally occurring

radioactive materialsNPL National Priority List for

the Superfund programNRC Nuclear Regulatory

CommissionOSHA Occupational Safety and

Health AdministrationpCi/L picocuries per literPET positron emission

tomographyRCRA Resource Conservation

and Recovery Actrad radiation absorbed doserem roentgen equivalent manRERT EPA Radiological

Emergency Response Team

RF radio frequencyRTG radioisotope thermoelec-

tric generatorSAB EPA’s Science Advisory

BoardSARA Superfund Amendments

and Reauthorization ActSDWA Safe Drinking Water ActTENORM technologically enhanced

naturally occurring radioactive material

TLD thermoluminescentdosimeter

TRANSCOM Transportation Tracking and Communication System

UNSCEAR United Nations Scientific Committee on the Effects of Atomic Radiation

WIPP Waste Isolation PilotPlant


82

Appendix

List ofAcronyms

CAppendix C: Additional Resources and References


Appendix

AdditionalResources

andReferences

83

American Nuclear Society555 North Kensington AvenueLa Grange Park, Illinois 60526Phone: 708/352-6611Fax: 708/352-0499Email: [email protected]://www.ans.orgThe American Nuclear Society is a not-for-profit, international, scientific and educa-tional organization. Its membership includesapproximately 13,000 individuals represent-ing 1,600 plus corporations, educationalinstitutions, and government agencies.

Concerned Citizens for Nuclear Safety107 CienegaSanta Fe, NM 87501Phone: 505/ 982-5611Fax: 505/986-0997 Email: [email protected] http://www.nuclearactive.org/Concerned Citizens for Nuclear Safety is anonprofit, nonpartisan organization thatworks to increase public awareness aboutradioactivity and the nuclear industry. Itparticularly focuses on Los Alamos NationalLaboratory (LANL) and the WasteIsolation Pilot Plant (WIPP).

Conference of Radiation Control ProgramDirectors, Inc.205 Capital AvenueFrankfort, KY 40601Phone: 502/227-4543Fax: 502/227-7862http://www.crcpd.org/The Conference of Radiation ControlProgram Directors, Inc. (CRCPD) is a non-

profit professional organization whose pri-mary membership is made up of individualsin state and local government who regulatethe use of radiation sources, and othersinterested in radiation protection.

Health Physics Society1313 Dolley Madison BoulevardSuite 402McLean, Virginia 22101Phone: 703/790-1745Fax: 703/790-2672Email: [email protected]://www.hps.orgThe Health Physics Society is an interna-tional professional scientific organizationthat is active in all aspects of radiation pro-tection including information dissemina-tion, standards development, education,preparation of position papers, and promo-tion of scientific conferences and commit-tees.

Idaho State UniversityDepartment of Physics and HealthPhysicsRadiation Information NetworkCampus Box 8106 Pocatello, ID 83209 Phone: 208/236-2350 Fax: 208/236-4649 Email: [email protected]://www.physics.isu.edu/radinf/This Idaho State University’s RadiationInformation Network web site contains awide range of information about Radiationand the professions of Radiation Protection.

Institute for Energy and EnvironmentalResearch6935 Laurel Avenue Takoma Park, MD 20912Phone: 301/270-5500Fax: 301/270-3029Email: [email protected]://www.ieer.orgThe Institute for Energy and EnvironmentalResearch is a nonprofit organization fundedprimarily through private foundation grants.It provides activists, policymakers, journal-ists, and the public with understandable sci-entific and technical information on energyand environmental issues, particularlynuclear materials and technologies.

International Atomic Energy AgencyP.O. Box 100, Wagramer Strasse 5A-1400 Vienna, AustriaPhone: +431-2600-0Fax: +431-2600-7Email: [email protected]://www.iaea.org/worldatom/The International Atomic Energy Agency(IAEA) serves as the world's central inter-governmental forum for scientific and tech-nical co-operation in the nuclear field, andas the international inspector of nuclearsafeguards and verification measures incivilian nuclear programs.

International Commission on RadiologicalProtectionS-171 16 Stockholm, Sweden Phone: +46-8-7297275Fax: +46-8-7297298Email: [email protected]://www.icrp.orgThe Commission works to advance for thepublic benefit the science of radiologicalprotection, in particular by providing rec-ommendations on all aspects of radiationprotection.

National Council on Radiation Protection and Measurements7910 Woodmont Avenue, Suite 800Bethesda, MD 20814-3095Phone: 301/657-2652Fax: 301/907-8768

Email: [email protected]://www.ncrp.comThe National Council on RadiationProtection and Measurements (NCRP)seeks to formulate and disseminate informa-tion, guidance and recommendations onradiation protection and measurementswhich represent the consensus of leadingscientific thinking.

National Institute of EnvironmentalHealth SciencesDepartment of Health and Human ServicesP.O. Box 12233111 Alexander DriveResearch Triangle Park, NC 27709Phone: 919/541-3345http://www.niehs.nih.aolThe National Institute of EnvironmentalHealth Sciences (NIEHS) undertakes bio-medical research, prevention and interven-tion efforts, and training, education, tech-nology transfer, and community outreach. Itfocuses on human health and human disease that result from three interactiveelements: environmental factors, individualsusceptibility, and age.

National Safety Council/Environmental Health Center1025 Connecticut Ave., NW, Suite 1200 Washington, DC 20036Phone: 202/293-2270Fax: 202/[email protected]://www.nsc.org/ehc.htmThe Environmental Health Center is a divi-sion of the National Safety Council, a nongovernmental, nonprofit public serviceorganization. EHC provides informationand resources on a range of environmentalissues.

Nevada Nuclear Waste Project Office1802 N. Carson Street, Suite 252Carson City, NV 89701Phone: 775/687-3744Fax: 775/687-5277Email: [email protected]://www.state.nv.us/nucwaste


Appendix

AdditionalResourcesandReferences

84


85

Appendix

AdditionalResources

andReferences

The State of Nevada’s agency for nuclearProjects works to assure that the health,safety, and welfare of Nevada's citizens,environment and economy are adequatelyprotected with regard to any federal high-level nuclear waste disposal activities in thestate.

New Mexico Environmental EvaluationGroup7007 Wyoming Blvd NE, Suite F-2Albuquerque, NM 87109Phone: 505/828-1003Fax: 505/828-1062Email: [email protected]://www.eeg.orgThe New Mexico Environment EvaluationGroup (EEG) is an interdisciplinary groupof scientists and engineers funded by theU.S. Department of Energy. EEG providesindependent technical evaluation of theWaste Isolation Pilot Plant (WIPP) toensure the protection of public health andsafety, and the environment of NewMexico.

New Mexico WIPP Transportation SafetyProgram2040 South PachecoSanta Fe, NM 87505Phone: 505/827-5950http://www.emnrd.state.nm.us/wippThe State of New Mexico has implementedthe WIPP Transportation Safety Program toensure the safe and uneventful transporta-tion of radioactive waste to the Departmentof Energy’s Waste Isolation Pilot Plant(WIPP) in southeastern New Mexico.

Nuclear Energy Institute176 I Street, NW, Suite 400 Washington, DC 20006Phone: 202/739-8009Fax: 573/445-2135Email: [email protected]://www.nei.orgThe Nuclear Energy Institute represents thecommercial nuclear energy industry. Itadvocates policies that ensure the beneficialuses of nuclear energy and related technologies.

Nuclear Information and ResourcesService1424 16th Street NW, Suite 404 Washington, DC 20036Phone: 202/328-0002Fax: 202/462-2183Email: [email protected]://www.nirs.orgThe Nuclear Information and ResourcesService is the information and networkingcenter for citizens and environmentalorganizations concerned about nuclearpower, radioactive waste, radiation, and sustainable energy issues.

Southern States Energy Board6325 Amherst CourtNorcross, GA 30092Phone: 770/242-7712Fax: 770/242-0421http://www.sseb.org/cpa_rmt.htmThe Southern States Energy Board (SSEB)is a non-profit interstate compact organiza-tion of 16 southern states and two territo-ries. SSEB develops, promotes and recom-mends policies and programs which protectand enhance the environment withoutcompromising the needs of future genera-tions. It has a Radioactive MaterialsTransportation Committee which partici-pates in the policymaking process concern-ing the U.S. Department of Energy'sradioactive materials transportation programs.

Union of Concerned Scientists2 Brattle Square, Cambridge, MA 02238-9105Phone: 617-547-5552 Email: [email protected]://www.ucsusa.orgThe Union of Concerned Scientists is anindependent nonprofit organization repre-senting scientists and other citizens aroundthe country. It does research, public educa-tion and citizen advocacy particularly onenvironmental and related issues.


86

U.S. Department of Energy600 Maryland Avenue, NW, Suite 760 Washington, DC 20024Phone: 202/488-6220National Transuranic Waste ProgramP.O. Box 3090Carlsbad, NM 88221-3090Phone: 505/234-7302Email: [email protected]://www.wipp.carlsbad.nm.usThe U.S. Department of Energy is the fed-eral agency responsible for developing andmanaging the country’s nuclear weapons,and for managing its waste and cleaning upits facilities. In addition, DOE has more30,000 scientists and engineers conductingresearch. The National Transuranic WasteProgram manages the Waste Isolation PilotPlant (WIPP) Facility.

U.S. Environmental Protection AgencyAriel Rios Building1200 Pennsylvania Avenue, N.W.Washington, DC 20460Phone: 202/564-9290http://www.epa.gov/radiationThe U.S. Environmental ProtectionAgency (EPA) is an independent federalagency that works to protect human healthand to safeguard the natural environment –air, water, and land.

U.S. Nuclear Regulatory Commission11555 Rockville PikeRockville, MD 20852-2738Phone: 301/415-7000http://www.nrc.govThe U.S. Nuclear Regulatory Commission(NRC) is an independent federal agencyresponsible for overseeing the use of nuclearmaterials in the United States. NRC's scopeof responsibility includes regulation of com-mercial nuclear power reactors; medical,academic, and industrial uses of nuclearmaterials; and the transport, storage, anddisposal of nuclear materials and waste.

University of MichiganNuclear Engineering and RadiologicalSciences1906 Cooley Building

2355 Bonisteel Blvd.Ann Arbor, MI 48109Phone: 734/764-4260Fax: 734/763-4540Email: [email protected]://www.engin.umich.edu/~nuclearThe University of Michigan’s Departmentof Nuclear Engineering and RadiologicalSciences conducts research and provideseducation on range of issues including radi-ation detection, fission power, fusion power,radiological health, and waste management.

Western Governors’ Association600 17th StreetDenver, CO 80202-5452Phone: 303/623-9378Email: [email protected]://www.westgov.org/wippThe Western Governors' Association is anindependent, non-partisan organization ofgovernors from 18 western states, twoPacific-flag territories and one common-wealth. The Association addresses key poli-cy and governance issues in naturalresources, the environment, human servic-es, economic development, internationalrelations and public management.

State Radiation Program ContactsList of state radiation program contactsavailable at: http://www.hsrd.ornl.gov/nrc/asframe.htm

Publications

“1997 Findings and Recommendations:Report to The U.S. Congress and TheSecretary of Energy.” U.S. Nuclear WasteTechnical Review Board (Arlington, VA,undated)

“A Fact Sheet on the Health Effects fromIonizing Radiation”(ANR459)(http://www.epa.gov/radiation/ionize2.htm). U.S.Environmental Protection Agency, Office ofRadiation & Indoor Air, RadiationProtection Division (Washington, DC, June1991)

Appendix



87

Appendix

AdditionalResources

andReferences

A Reporter’s Guide to the Waste Isolation PilotPlant (WIPP). National Safety Council,Environmental Health Center(Washington, DC, September 1997)

Accelerating Cleanup: Paths to Closure(DOE/EM-0342). U.S. Department ofEnergy, Office of EnvironmentalManagement (Washington, DC, February1998)

“ACHRE Report: How Do ScientistsDetermine the Long-Term Risks fromRadiation?” (http://tisnt.eh.doe.gov/ohre/roadmap/achre/intro_9_8.html). U.S.Department of Energy, Advisory Committeeon Human Radiation Experiments(Washington, DC, June 11, 1996)“Americans ambivalent on nuclear poweruse: Poll finds only 45% support it for ener-gy.” The Associated Press (Washington,DC, March 19, 1999)

“An Overview of Mixed Waste”(http://www.epa.gov/radiation/mixed-waste/mw_pg3.htm). U.S. EnvironmentalProtection Agency, Mixed Waste Team(Washington, DC, Feb. 6, 1998)

An SAB Report: Future Issues inEnvironmental Radiation (EPA-SAB-RAC-95-006). U.S. Environmental ProtectionAgency, Science Advisory Board, RadiationEnvironmental Futures Subcommittee(Washington, DC, March 1995)

“Assessment of Health Effects fromExposure to Power-Line Frequency Electricand Magnetic Fields: Working GroupReport” (http://www.niehs.nih.gov/emfrapid/html/WGReport/doc.html).National Institutes of Health, NationalInstitute of Environmental Health Sciences(Washington, DC, June 1998)

“Background on 40 CFR Part 197:Environmental Radiation ProtectionStandards for Yucca Mountain.” Capt.Raymond L. Clark, U.S. EnvironmentalProtection Agency, Office of Radiation andIndoor Air (Washington, DC, undated)

“Chronology of Key Political and PolicyDevelopments Regarding The YuccaMountain Repository Program”(http://www.state.nv.us/nucwaste/yucca/chrono.htm). State of Nevada, Nuclear WasteProject Office (Carson City, NV, undated)

“A Citizen’s Guide To Radon.” U.S.Environmental Protection Agency(Washington, DC, September 1992)

“Clinically Observed Effects in IndividualsExposed to Radiation as a Result of theChernobyl Accident”(http://www.iaea.or.at/worldatom/thisweek/preview/chernobyl/paper1.html). International Atomic Energy Agency(Vienna, Austria, undated)

Closing the Circle on the Splitting of theAtom (DOE/EM-0266). U.S. Departmentof Energy, Office of EnvironmentalManagement (Washington, DC, January1996)

Committed to Results: DOE’s EnvironmentalManagement Program (DOE/EM-0152P)U.S. Department of Energy, Office ofEnvironmental Management (Washington,DC, April 1994)

“Consumer’s Guide to Radon Reduction.”U.S. Environmental Protection Agency(Washington, DC, August 1992)

“Decommissioning of Nuclear Power Plants(http://www.nei.org/pressrm/facts/infob17.htm). Nuclear Energy Institute (Washington,DC, February 1998)

“Disposal of Low-Level Radioactive Waste”(http://www.nei.org/library/infob30.htm).Nuclear Energy Institute (Washington, DC,April 1998)“Disposal of Naturally Occurring andAccelerator-Produced Radioactive Materials(NARM).” Radioactive Waste Disposal: AnEnvironmental Perspective (EPA 402-K-94-001). U.S. Environmental ProtectionAgency, Office of Radiation and Indoor Air,


88

Radiation Protection Division(Washington, DC, August 1994)

Electromagnetic Fields and Human Health.John E. Moulder, Ph.D., Professor ofRadiation Oncology, Medical College ofWisconsin (Madison, WI, June 1998)

“EMFs’ Biological Influences:Electromagnetic fields exert effects on andthrough hormones” (http://www.science-news.org/sn_arc98/1_10_98/bob1.htm).Janet Raloff, Science News Online(Washington, DC, Jan. 10, 1998)

“Experts Critical of DOE Technical Reporton Yucca Mountain” (http://www.nas.edu/onpi/pr/nov95/yucca.html). NationalAcademy of Sciences, National ResearchCouncil (Washington, DC, Nov. 30, 1995)

“Fact Sheet: Setting EnvironmentalStandards For Yucca Mountain”(http://www.epa.gov/rpdweb00/yucca/fac-trev.htm). U.S. Environmental ProtectionAgency, Office of Radiation and Indoor Air,Radiation Protection Division(Washington, DC, Jan. 21, 1998)

“Facts about Food Irradiation”(http://www.iaea.or.at:80/worldatom/infore-source/other/food/status.html). Food andAgricultural Organization, InternationalAtomic Energy Agency and World HealthOrganization, International ConsultativeGroup on Food Irradiation (Vienna,Austria, undated)

“Failure of the Nuclear RegulatoryCommission: Whistleblowers are doing theNRC’s job” (http://www.igc.apc.org/nrdc/bkgrd/nuusnrc.html). Natural ResourcesDefense Council (New York, NY, 1996)

“Food Irradiation”(http://www.acesag.auburn.edu/department/family/foodsafe/irrad.htm). W.T. Roberts andJean Olds Weese, Auburn University(Auburn, AL, undated)

Appendix


“Food Irradiation”(http://www.nei.org/pressrm/facts/infob34.htm). Nuclear Energy Institute (Washington,DC, 1998)

“Frequently Asked Questions about MixedWaste”(http://www.epa.gov/rpdweb00/mixed-waste/mw_pg 17.htm). U.S. EnvironmentalProtection Agency, Mixed Waste Team(Washington, DC, Dec. 8, 1998)

“Haste Makes Waste” (http://www.essen-tial.org/orgs/FOE/scissors95/greenpart13.html). Friends of the Earth, Green ScissorsReport (San Francisco, CA, undated)“Hazard-Based Classification of NuclearWaste – A Wiser Arrangement”(http://www.nonukes.org/w29hazl.htm).Ward A. Young, Nuclear GuardianshipForum, #3 (Spring 1994)

“Health and Environmental Impacts ofNuclear Weapons Production: Radioactivityin the Fernald Neighborhood”(http://www.ieer.org/ieer/sdafiles/vol_5/5-3/fern-res.html). Arjun Makhijani, Institutefor Energy and Environmental Reserch(Takoma Park, MD, March 1997)

“High-Level Nuclear Waste”(http://www.nei.org/library/infob31.htm).Nuclear Energy Institute (Washington, DC,June 1998)

“High-Level Waste: What will we do withused nuclear fuel?” Nuclear Energy Institute(Washington, DC, undated)

“Home Buyer’s and Seller’s Guide toRadon.” U.S. Environmental ProtectionAgency (Washington, DC, July 2000)

“How Can We Face the Challenge? – FiftyYears at a Time”(http://www.nonukes.org/r05howca.htm).Molly Young Brown, Nuclear GuardianshipLibrary (undated)


89

Appendix

AdditionalResources

andReferences

“How Do Radioactive Materials MoveThrough the Environment to People?”(RER-25) (http://www.ag.ohio-state.edu/~rer/rerhtml/rer_25.html). OhioState University Extension Research(Columbus, OH, undated)

“Human Radiation Experiments.” InterimReport of the Advisory Committee onHuman Radiation Experiments(Washington, DC, Oct. 21, 1994)

“International law and nuclear energy:Overview of the legal framework”(http://ecoluinfo.unige.ch/colloques/Chernobyl/Pages/Opelz.html). Mohamed Elbaradei,Edwin Nwogugu, and John Rames,International Atomic Energy Agency(Vienna, Austria, undated)

“Ionizing Radiation Series No. 1”(ANR459) (http://www.epa.gov/radiation/ionize.htm). U.S. EnvironmentalProtection Agency, Office of Radiation &Indoor Air, Radiation Protection Division(Washington, DC, September 1990)

“Ionizing Radiation-It’s Everywhere!” LosAlamos Science, Number 23, Los AlamosNational Laboratory (Los Alamos, NM,1995)

“Irradiation in the Production, Processingand Handling of Food” (21 CFR Part 179).Federal Register, Vol. 62, No. 232, pp.64101-64107, U.S. Department of Healthand Human Services, Food and DrugAdministration (Washington, DC, Dec. 3,1997)

“Irradiation: A Safe Measure for SaferFood” (http://www.fda.gov/fdac/fea-tures/1998/398_rad.html). FDA Consumer,U.S. Food and Drug Administration(Washington, DC, May-June 1998)“Irradiation-An Overview of a SafeAlternative to Fumigation.” U.S.Department of Agriculture, AgriculturalResearch Service (Washington, DC,October 1997)

“Issues Paper on Radiation Site CleanupRegulations” (http://www.epa.gov/radia-tion/cleanup/html/issueppr.txt). U.S.Environmental Protection Agency, Office ofRadiation and Indoor Air (Washington,DC, September 1993)

“Key Federal Laws and Regulations”(http://www.rw.doe.gov/pages/intro/96ar/ocrwm008.htm). U.S. Department of Energy,Office of Environmental Management,Office of Civilian Radioactive WasteManagement (Washington, DC, 1996)

“Leukemia Clusters Near La Hague andSellafield” (http://www.ieer.org/ieer/ensec/no-4/lahague.html). Anita Seth,Institute for Energy and EnvironmentalResearch (Takoma Park, MD, February1998)

“Living with Radiation.” NationalGeographic, Vol. 175, No. 4, pp. 402-437(Washington, DC, April 1989)

“Low-Level Radioactive Waste Fact Sheets”(RER-00, -10, -12, -13, -14, -32, -33, -40, -41, -42, -43, -44, -45, -46, -47, -49, -50, -61,-65, and –66) (http://www.ag.ohio-state.edu/~rer/). Ohio State UniversityExtension Research (Columbus, OH, undated)

“Low-Level Waste: What should we knowabout it?” Nuclear Energy Institute(Washington, DC, undated)

“Managing Used Fuel from Nuclear PowerPlants” (http://www.nei.org/pressrm/briefs/usedfuel.htm). Nuclear EnergyInstitute (Washington, DC, February 1998)

“Medical and Industrial Uses of RadioactiveMaterials” (http://www.nei.org/pressrm/facts/infob35.htm). Nuclear EnergyInstitute (Washington, DC, February 1998)


90

“Medical Waste: Trojan Horse? ‘Don’t gethooked by medical arguments’”(http://www.nonukes.org/r07waste.htm)Wendy Oser, Nuclear Guardianship Forum,#3, Spring 1994

“Mixed Waste FAQ”(http://www.epa.gov/radiation/mixed-waste/mw_pg17.htm). U.S. EnvironmentalProtection Agency, Mixed Waste Team(Washington, DC, March 4, 1998)

“Nuclear Energy: Pros, Cons, and Prospects”(http://www.lehigh.edu/~ghh2/index.html).Kyle Kononowitz, Jared Hess, and GreggHilzer, Lehigh University (Bethlehem, PA,undated)

“Nuclear Power Plant Oversight: Industryand Government Roles”(http://www.nei.org/pressrm/facts/infob10.htm). Nuclear Energy Institute (Washington,DC, February 1998)

The Nuclear Waste Primer. League of WomanVoters Education Fund (Washington, DC,1993)

“Orphaned Sources Initiative”(http://www.epa.gov/radiation/cleanmetals/orphan.htm). U.S. Environmental ProtectionAgency, Office of Radiation and Indoor Air,Radiation Protection Division(Washington, DC, undated)

“Plant Regulation”(http://www.nei.org/safe/reg.htm). NuclearEnergy Institute (Washington, DC, undated)

“Questions and Answers about EMF:Electric and Magnetic Fields Associatedwith the Use of Electric Power”(http://www.niehs.nih.gov/oc/factsheets/emf/emf.htm). National Institutes of Health,National Institute of Environmental HealthSciences (Washington, DC, January 1995(revised Jan. 27, 1998))“Questions and Answers about NuclearEnergy” (http://www.nuc.u

Appendix


mr.edu/~ans/QA.html). University ofMissouri-Rolla American Nuclear Society(Rolla, MO, undated)

“Radiation and Risk: A Hard Look at theData.” Los Alamos Science, Number 23,Los Alamos National Laboratory (LosAlamos, NM, 1995)

“Radiation Protection Today andTomorrow: An Assessment of the PresentStatus and Future Perspectives of RadiationProtection” (http://www.nea.fr/html/rp/rp.html). Organization for EconomicCooperation and Development, NuclearEnergy Agency, Committee on RadiationProtection and Public Health (Paris,France, 1993)

“Radiation Roulette” (http://www.newscien-tist.com/ns/971115/radiation.html). NewScientist (Great Britain, Nov. 15, 1997)

“Radiation Standards and Organizations: AHistorical Perspective”(http://www.nei.org/pressrm/facts/infob25.htm). Nuclear EnergyInstitute (Washington, DC, February 1998)

Radiation: Risks and Realities (EPA 402-K-92-004). U.S. Environmental ProtectionAgency, Office of Air and Radiation(Washington, DC, August 1993)

“Radiation Waste: Too Hot to Handle? AnInterview With Dr. Rustum Roy on How ToPackage Nuclear Waste”(http://www.nonukes.org/r27pack.htm).Francis Macy, Nuclear Guardianship Forum,Issue 2, Spring 1993

Radioactive Waste Disposal: AnEnvironmental Perspective (EPA 402-K-94-001). U.S. Environmental ProtectionAgency, Office of Radiation & Indoor Air,Radiation Protection Division(Washington, DC, August 1994)“Radioactive Waste: Production, Storage,

Disposal” (NUREG/BR-0216). U.S.


91

Appendix

AdditionalResources

andReferences

Nuclear Regulatory Commission(Washington, DC, July 1996)

“Radioactive Waste: Yucca Mountain MayBe Unstable For Permanent Repository,Study Finds”(http://www.junkscience.com/news/yucca.htm). Bureau of National Affairs, DailyEnvironment Report (Washington, DC,March 30, 1998)

“Radionuclides (Uranium, Radium, andRadon)” (wysiwyg://42/http:www.epa.gov/ttn/uatw/hlthef/radionuc.html).U.S. Environmental Protection Agency,Office of Air Quality Planning & Standards(Washington, DC, May 26, 1998)

Ready to Respond (EPA 520/1-91-027). U.S.Environmental Protection Agency, Office ofAir and Radiation (Washington, DC,February 1992)

The Regulation and Use of Radioisotopes inToday’s World (NUREG/BR-0217). U.S.Nuclear Regulatory Commission(Washington, DC, July 1996)

“Regulatory History of Mixed Waste”(http://www.epa.gov/radiation/mixed-waste/mw_pg4.htm). U.S. EnvironmentalProtection Agency, Mixed Waste Team(Washington, DC, April 9, 1998)

“Safety in Motion: Transportation ofradioactive materials.” Nuclear EnergyInstitute (Washington, DC, undated)

“Science for the Critical Masses: RadiationDoses” (http://www.ieer.org/ieer/ensec/no-4/dose-exp.html). Institute for Energy andEnvironmental Research (Takoma Park,MD, February 1998)

“Science For The Critical Masses:Radiation Protection” (http://www.ieer.org/ieer/ensec/no-4/protec.html). Institute forEnergy and Environmental Research(Takoma Park, MD, February 1998)“Science for the Critical Masses: Units of

Radiation and Dose” (http://www.ieer.org/ieer/ensec/no-4/units.html). Institute forEnergy and Environmental Research(Takoma Park, MD, February 1998)

“Site Recommendation”(http://www.ymp.gov/timeline/sr/index.htm). U.S. Department of Energy, Office ofCivilian Radioactive Waste Management(Washington, DC, undated)

“State or Federal Regulations: Which do Iuse?” (http://www.epa.gov/radiation/mixed-waste/mw_pg6.htm) U.S. EnvironmentalProtection Agency, Mixed Waste Team(Washington, DC, Feb. 6, 1998)

“Static Electric and Magnetic Fields andCancer FAQs” (http://www.mcw.edu/gcrc/cop/static-fields-cancer-FAQ/toc.html);and “Cellular Phone Antennas and HumanHealth” (http://mcw.edu/gcrc/cop/cell-phone-health-FAQ/toc.html).

“Sustainable Development and NuclearPower” (http://www.iaea.org/worldatom/inforesource/other/develop-ment/index.html). International AtomicEnergy Agency (Vienna, Austria, undated)

“The TMI 2 Accident: Its Impact, ItsLessons” (http://www.nei.org/pressrm/facts/infob19.htm). Nuclear EnergyInstitute (Washington, DC, April 1998)

“TIP:36-Biological Effects of Radiation”(http://www.nrc.gov/OPA/gmo/tip9836.htm).U.S. Nuclear Regulatory Commission(Washington, DC, undated)

“Transporting Radioactive Materials”(http://www.nei.org/pressrm/facts/infob32.htm). Nuclear Energy Institute (Washington,DC, April 1998)

The U.S. Nuclear Regulatory Commission’sRegulatory Program. U.S. Nuclear RegulatoryCommission, Office of Nuclear Material Safetyand Safeguards (Washington, DC, undated)


92

“Waste Disposal”(http://www.em.doe.gov/em30/wastdisp.html) U.S. Department of Energy, Office ofEnvironmental Management, Office ofWaste Management (Washington, DC,April 14, 1998)

“What Are the Health Effects of IonizingRadiation?” (RER-24); “How Are PeopleProtected From Ionizing Radiation?” (RER-26) (http://www.ag.ohio-state.edu/~rer/rerhtml/rer_24.html;rer_26.html). Ohio StateUniversity Extension Research (Columbus,OH, undated)

“What Are the Sources of IonizingRadiation?” (RER-22) (http://www.ag.ohio-state.edu/~rer/rerhtml/rer_22.html). OhioState University Extension Research(Columbus, OH, undated)

“What Is Radioactive Material and HowDoes It Decay?” (RER-20); “What IsIonizing Radiation?” (RER-21); “How isIonizing Radiation Measured?” (RER-23)(http://www.ag.ohio-state.edu/~rer/rerhtml).Ohio State University Extension Research(Columbus, OH, undated)

“What Processes Use RadioactiveMaterials?” (RER-11) (http://www.ohio-line.ag.ohiostate.edu/~rer/rerhtml/rer_11.html). Ohio State University ExtensionResearch (Columbus, OH, undated)

“What We Know About Radiation.”National Institutes of Health, Office ofCommunications (Washington, DC, April11, 1994)

“White Paper: Research Needs forNonionizing Radiation”(http://www.cdc.gov/niosh/ctwpnira.html).National Institute for Occupational Safetyand Health/Centers for Disease Control andPrevention (Washington, DC/Atlanta, GA,March 1998)

Appendix


DAppendix D: Brief Chronology ofRadioactive Materials and Radioactive

Waste in the United States


93

Appendix

BriefChronology

ofRadioactive

Materialsand

RadioactiveWaste in

the UnitedStates

1895 Roentgen discovers X-rays. 1896 First diagnostic X-ray in US.1898 Marie & Pierre Curie coin

word “radioactivity.” 1903 Marie and Pierre Curie

awarded the Nobel Prize for Physics.

1905 Albert Einstein develops theory about the relationship of mass and energy.

1910 Curie unit defined as activity of 1 gram of radium.

1915 The British Roentgen Societyadopted a resolution to protect people from overexposure to X-rays.

1922 Many American organizationsadopted the British protectionrules.

1925-1929 The saga of radium dial painters unfolds.

1928 Organization of US Advisory Committee on X-ray and Radium Protection (predecessor of National Council on Radiation Protection).

1939 Enrico Fermi patents first reactor (conceptual plans).

1942 The Manhattan Project is formed to secretly build the atomic bomb before the Germans.

1942 Enrico Fermi demonstrates the first self-sustaining

nuclear chain reaction in a lab at the University of Chicago.

1946 Atomic Energy Act is passed; establishes Atomic Energy Commission.

1946 The U.S. Advisory Committee was reorganized and renamed the National Committee on Radiation Protection and operating out of the Bureau of Standards.

1951 First electricity is generated from atomic power at EBR-1 Idaho National Engineering Lab, Idaho Falls.

1954 Atomic Energy Act of 1954 ispassed to promote the peaceful uses of nuclear energy through private enterprises and to implement President Eisenhower's Atomsfor Peace Program.

1954 The first nuclear submarine, U.S.S. Nautilus, is launched.

1955 Arco, Idaho becomes the fist U.S. town to be powered by nuclear energy.

1957 The first U.S. large-scale nuclear power plant begins operating in Shipingport, Pennsylvania.

1957 United Nations establishes the International Atomic Energy Agency (IAEA)


Appendix

BriefChronologyofRadioactiveMaterialsandRadioactiveWaste inthe UnitedStates

94

1958 Bureau of Radiological Healthorganized within US Public Health Service.

1959 Federal Radiation Council (FRC) formed to advise the US President about radiation matters, especially standards.

1962 The first commercial low-level waste disposal site was established in Beatty, Nevada.

1968 Nuclear Nonproliferation Treaty calling for halting the spread of nuclear weapons capabilities is signed.

1970 U.S. Environmental Protection Agency is formed. Responsibilities include radiation protection.

1970 National Environmental Policy Act is signed requiring the Federal government to review the environmental impact of any action - such asconstruction of a facility - that might significantly affect the environment.

1971 Six commercial low-level waste sites operating.

1972 Computer axial tomography, commonly known as CAT scanning, is introduced. A CAT scan combines many high-definition cross-sectionalX-rays to produce a two-dimensional image of a patients anatomy.

1972 AEC reveals that since 1946 radioactive waste was dumpedoff shore of US coast; biggest dumps near San Francisco, CA, 47,500 55-gallon drums.

1974 Atomic Energy Commission isabolished and the Nuclear Regulatory Commission and the Energy Research and Development Administration are established.

1975 West Valley, New York low-level waste site closed after water overflowed from two of its burial trenches.

1976 The Resource Conservation and Recovery Act (RCRA) ispassed to protect human health and the environment from the potential hazards of waste disposal.

1977 The U.S. Department of Energy replaces the Energy Research and Development Administration.

1977 Maxey Flats, Kentucky low-level waste site closed after some radioactive materials migrated from the site and thestate imposed additional surcharges making disposal uneconomical.

1978 Sheffield, Illinois low-level waste site closed after reaching capacity.

1979 Three Mile Island (Middletown, Pa) nuclear power plant suffers hydrogen explosions and a partial core meltdown.

1979 Beaty, Nevada and Richland, Washington low-level waste sites closed temporarily because damaged and leaking nuclear waste containers werebeing delivered.

1980 The Low-Level Radioactive Waste Policy Act is passed, making states responsible for the disposal of their own low-level nuclear waste, such as from the hospitals and industry.

1980 The Comprehensive Environmental Response, Compensation, and Liability Act (also known as Super fund) is passed in response to the discovery in the late 1970s of a large number of abandoned, leaking hazardouswaste dumps.

1983 The Nuclear Waste Policy Act of 1982 is signed, authorizing the development


Appendix

BriefChronology

ofRadioactive

Materialsand

RadioactiveWaste in

the UnitedStates

95

of a high-level nuclear waste repository.

1985 Because no low-level waste state compacts had yet been ratified or sites selected, Congress amended the act to create siting milestones, deadlines for compliance, andpenalties for failure to meet the deadlines. It provided thaton Jan. 1, 1993, the three states with sites (Washington,South Carolina and Nevada) could refuse to accept low-level waste generated outside their borders by states that arenot in their respective compacts.

1986 Chernobyl Nuclear Reactor meltdown and fire occur in the Soviet Union. Much radioactive material is released.

1987 Nuclear Waste Policy Amendments Act designates Yucca Mountain, Nevada, for scientific investigation as onlycandidate site for the US's first geological repository for high-level radioactive waste and spent nuclear fuel.

1989 DOE changes its focus from nuclear materials production to environmental cleanup by forming the Office of Environmental Restoration and Waste Management.

1991 The United States and SovietUnion sign historic agreementto cut back on long-range nuclear weapons by ore than 30 percent over the next seven years.

1992 The Waste Isolation Pilot Plant (WIPP) Land Withdrawal Act withdraws public lands for WIPP, a test repository for transuranic nuclear waste located in a saltdeposit deep under the desert.

1993 The Beatty, Nevada, low-levelwaste site closed to low-level waste.

1996 The United Nations approves the Comprehensive Test Ban Treaty which bans nuclear test explosions

1999 An accident at the uranium processing plant at Tokaimura, Japan, exposed fifty-five workers to radiation.One worker later dies.

1999 The Waste Isolation Pilot Plant began receiving shipments of transuranic waste.

Sources:

“A Brief Chronology of Radiation andProtection.” by J. Ellsworth Weaver III1994,1995, http://www.sph.umich.edu/eih/UMSCHPS/chrono.htm#top

The Nuclear Waste Primer, League ofWomen Voters, 1993

“Radiation Protection: An Historical Perspective,” U.S. Environmental Protection Agency

“Nuclear Age Timeline,” U.S. Departmentof Energy

BLANK

EAmericium-241 – Used in many smokedetectors for homes and businesses ... tomeasure levels of toxic lead in dried paintsamples ... to ensure uniform thickness inrolling processes like steel and paper pro-duction ... and to help determine where oilwells should be drilled.

Cadmium-109 – Used to analyze metalalloys for checking stock, scrap sorting.

Calcium-47 – Important aid to biomedicalresearchers studying the cellular functionsand bone formation in mammals.

Californium-252 – Used to inspect airlineluggage for hidden explosives ... to gaugethe moisture content of soil in the roadconstruction and building industries ... andto measure the moisture of materials storedin soils.

Carbon-14 – Major research tool. Helps inresearch to ensure that potential new drugsare metabolized without forming harmfulby-products. Used in biological research,agriculture, pollution control, and archeology.

Cesium-137 – Used to treat canceroustumors ... to measure correct patient dosagesof radioactive pharmaceuticals ... to meas-ure and control the liquid flow in oilpipelines ... to tell researchers whether oilwells are plugged by sand ... and to ensurethe right fill level for packages of food,drugs and other products. (The products inthese packages do not become radioactive.)

Chromium-51 – Used in research in redblood cell survival studies.

Cobalt-57 – Used as a tracer to diagnosepernicious anemia.

Cobalt-60 – Used to sterilize surgical instru-ments ... and to improve the safety and reli-ability of industrial fuel oil burners. Used incancer treatment, food irradiation, gauges,and radiography.

Copper-67 – When injected with mono-clonal antibodies into a cancer patient,helps the antibodies bind to and destroy thetumor.

Curium-244 – Used in mining to analyzematerial excavated from pits ... and slurriesfrom drilling operations.

Gallium-67 – Used in medical diagnosis.

Iodine-123 – Widely used to diagnose thy-roid disorders and other metabolic disordersincluding brain function.

Iodine-125 – Major diagnostic tool used inclinical tests and to diagnose thyroid disor-ders. Also used in biomedical research.

Iodine-129 – Used to check some radioac-tivity counters in in vitro diagnostic testinglaboratories.

Iodine-131 – Used to treat thyroid disor-ders. (Former President George Bush andMrs. Bush were both successfully treated for

Appendix E: Major Uses of Radioisotopes


Appendix

Major Uses of Radioiso-

topes

97

Graves' disease, a thyroid disease, withiodine- 131.)

Iridium-192 – Used to test the integrity ofpipeline welds, boilers and aircraft parts andin brachytherapy/tumor irradiation.

Iron-55 – Used to analyze electroplatingsolutions and to detect the presence of sul-phur in the air. Used in metabolismresearch.

Krypton-85 – Used in indicator lights inappliances such as clothes washers and dry-ers, stereos, and coffee makers ... to gaugethe thickness of thin plastics and sheetmetal, rubber, textiles and paper... and tomeasure dust and pollutant levels.

Nickel-63 – Used to detect explosives, andin voltage regulators and current surge pro-tectors in electronic devices, and in elec-tron capture detectors for gas chro-matographs.

Phosphorus-32 – Used in molecular biolo-gy and genetics research.

Phosphorus-33 – Used in molecular biolo-gy and genetics research.

Plutonium-238 – Has powered more than20 NASA spacecraft since 1972.

Polonium-210 – Reduces the static chargein production of photographic film andother materials.

Promethium-147 – Used in electric blanketthermostats ... and to gauge the thickness ofthin plastics, thin sheet metal, rubber, tex-tile and paper.

Radium-226 – Makes lightning rods moreeffective.

Selenium-75 – Used in protein studies inlife science research.

Sodium-24 – Used to locate leaks in indus-trial pipe lines and in oil well studies.

Strontium-85 – Used to study bone forma-tion and metabolism.

Sulphur-35 – Used in survey meters byschools, the military and emergency man-agement authorities. Also used in cigarettemanufacturing sensors and medical treat-ment.

Technetium-99m – Used in genetics andmolecular biology research. The most wide-ly used radioactive pharmaceutical for diag-nostic studies in nuclear medicine. Differentchemical forms are used for brain, bone,liver, spleen and kidney imaging and alsofor blood flow studies.

Thallium-201 – Used in nuclear medicinefor nuclear cardiology and tumor detection.

Thallium-204 – Measures the dust and pol-lutant levels on filter paper ... and gaugesthe thickness of plastics, sheet metal, rub-ber, textiles and paper.

Thoriated Tungsten – Used in electric arcwelding rods in construction, aircraft, petro-chemical and food processing equipmentindustries. They produce easier starting,greater arc stability and less metal contami-nation.

Thorium-229 – Helps fluorescent lights lastlonger.

Thorium-230 – Provides coloring and fluo-rescence in colored glazes and glassware.

Tritium – Major tool for biomedicalresearch. Used for life science and drugmetabolism studies to ensure the safety ofpotential new drugs ... for self-luminous air-craft and commercial exit signs ... for lumi-nous dials, gauges and wrist watches ... toproduce luminous paint, and for geologicalprospecting and hydrology.

Uranium-234 – Used in dental fixtures likecrowns and dentures to provide a naturalcolor and brightness.


Appendix

Major Uses of Radioiso-topes

98

Uranium-235 – Fuel for nuclear powerplants and naval nuclear propulsion systems... and used to produce fluorescent glass-ware, a variety of colored glazes and walltiles.

Xenon-133 – Used in nuclear medicine forlung ventilation and blood flow studies.

Source: U.S. Nuclear RegulatoryCommission, “The Regulation and Use OfRadioisotopes in Today's World”(NUREG/BR-0217)


Appendix

Major Uses of Radioiso-

topes

99

National Safety Council’s Environmental Health Center1025 Connecticut Ave., NW Suite 1200

Washington, DC 20036202/293-2270

http://www.nsc.org/ehc.htm

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