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Radiation Physics and Chemistry 71 (2004) 8–15
ARTICLE IN PRESS
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Opening lecture
Reflections on the evolution and current status of theradiation industry
John Masefield*
Steris Isomedix Services Inc., 5960 Heisley Road, Mentor, OH 44060, USA
Ladies and gentlemen, as Co-Chairman of this meet-
ing, may I extend my very warm welcome to all of you,
your spouses, family members and friends to Chicago,
and to the 13th International Meeting on Radiation
Processing!
We have with us today over 400 distinguished
delegates from over 30 countries around the world.
You represent Government, Academia, and various
industries and are gathered here to share, yet again, the
most recent developments that have taken place in our
industry.
Chicago was selected as the venue for this Conference,
because of its exciting and dynamic reputation as one of
the world’s leading conference cities and the fact that it
hosts the headquarters of a number of the multi-national
companies that utilize ionizing radiation technology.
When it was suggested that I give this keynote
address, I must confess, it was a challenge to decide
what I could talk about of value that had not already
been addressed on prior occasions.
I then reflected on recent events that are impacting the
way we think and live, including acts of terror, concern
over dirty bombs, and security issues, all of which have
led to renewed discussion these days, about the use of
nuclear energy, in the generation of electrical power.
This was reinforced by the recent electrical blackout in
the North East corridor of North America the
consequences of which I’m sure some of you experienced
first hand! Though in this instance not caused by a
shortage of the electrical power, it emphasized in my
mind the total disruption that occurs when we are
suddenly without electricity, and reminded me of the
wise and visionary statement made ‘‘over 30 years’’ ago
by one of the world’s most renowned theoretical
8-387-7078.
ess: john [email protected] (J. Masefield).
ee front matter r 2004 Elsevier Ltd. All rights reserv
dphyschem.2004.05.031
physicists, Edward Teller, in his book, called ‘‘Energy
from Heaven and Earth’’:
No single prescription exists for a solution to the
energy problem.
Petroleum is not enough,
Coal is not enough,
Nuclear energy is not enough,
Solar energy and geothermal energy are not enough,
New ideas and developments will not be enough by
themselves,
Only the proper contribution of all of these will
suffice.
Being mindful of the fact that a small number of
certain types of nuclear power reactors as an adjunct to
producing electricity are used to produce Co-60 that is
the backbone of a major part of the radiation processing
industry, and that particle accelerators also depend
heavily upon the availability of an economical and
plentiful supply of electricity, I decided that it is
appropriate to commence by reflecting upon the origins,
merits, and current status of nuclear power. You will
hear more about the future of nuclear power during the
course of this conference.
I will also touch briefly upon developments that are
taking place in various sectors of the radiation proces-
sing industry.
You know, it is truly symbolic that this meeting is
being held in Chicago in that it was here some 61 years
ago that the world entered the ‘‘nuclear age’’!
It was on the floor of a squash court beneath the
University of Chicago’s athletic stadium on December
2nd 1942, that a group of scientists led by Italian
physicist Enrico Fermi witnessed the first sustained
ed.
ARTICLE IN PRESSJ. Masefield / Radiation Physics and Chemistry 71 (2004) 8–15 9
nuclear chain reaction involving the fissioning of
uranium in the world’s first nuclear reactor which
became known as ‘‘Chicago Pile-1’’, which I’m sure
that many of you know about and which is depicted in a
well known painting.
This reactor was made up of a cubic matrix of
uranium, graphite to moderate the speed of the
neutrons, and neutron absorbing control rods that
could be withdrawn or inserted to start, or arrest, the
chain reaction.
So, how did this come about? Well, by 1900 physicists
knew the atom contained large quantities of energy.
British physicist ‘‘Ernest Rutherford’’ who was called
the father of nuclear science because of his considerable
contributions to the theory of atomic structure wrote in
1904:
If it were possible to control, at will, the rate of
disintegration of the radio elements, an enormous
amount of energy could be obtained from a small
amount of matter.
As you undoubtedly know, one year later Albert
Einstein developed his theory on the relationship
between mass and energy, contained in the mathematical
formula, E=mc2, or, energy equals mass times the speed
of light squared.
It was in 1934 that Enrico Fermi together with his
associates conducted experiments in Rome showing that
neutrons could split many kinds of atoms, a process
which became known as ‘‘fission’’.
When neutrons were fired into uranium it was found
that the uranium atoms split and that the atomic mass of
the left over fission products did not total the original
uranium’s atomic mass! Einstein’s by then famous
theory was used to show that the mass lost in the
fissioning process had been converted into energy which
is then released in the form of ‘‘heat’’. Two or three
neutrons are also released along with the heat with every
fission reaction. These neutrons may hit other atoms
causing further fissioning.
A series of fissions is called ‘‘a chain reaction’’. If
enough uranium is brought together, under the right
conditions a continuous chain reaction occurs. This self-
sustaining chain reaction produces a great deal of heat
energy which can then be used in the generation of
electricity.
How? Let us now talk about how nuclear plants work.
They generate electricity, just like any other steam-
electric power generating plant. Water is heated and
steam from the boiling water turns turbines and
generates electricity. The main difference between the
various types of steam-electric plants is the ‘‘heat’’
source. Heat from a self-sustaining chain reaction boils
the water in a nuclear power plant as opposed to
burning coal, oil, or gas in other plants to heat water.
Here is the compelling basic energy fact which makes
atomic energy so attractive:
The fission of an atom of uranium produces 10
million times the energy produced by the combustion
of an atom of carbon from coal.
After the end of the Second World War under US
President Eisenhower’s ‘‘Atoms for Peace Program’’ a
major goal of atomic research was to show that nuclear
energy could be used as a safe and environmentally
friendly means of producing electricity. This led to the
first commercial nuclear power plant in Shippinport,
Pennsylvania which reached full operating power in 1957.
During the same period research also proceeded on
the development of nuclear reactors to power submar-
ines and, it is worthy of note, that in 1955 the US Navy
submarine ‘‘Nautilus’’ traveled over 62,000 miles pow-
ered by a single lump of uranium the size of a golf ball!
So, you can imagine how powerful and useful this type
of energy can be! Currently, some 150 ships are now
propelled by more than 200 nuclear reactors. The US
Navy alone has to date some 5400 reactor years of
accident-free experience.
The nuclear power industry grew rapidly in the 1960s.
Utility companies saw this new form of electricity
production as economical environmentally clean and
safe. Electricity was going to be so cheap and plentiful
that we would not need electric meters in our homes!
In the 1970s and 1980s however, growth in the
construction of new reactors slowed due to (a) growing
concerns over reactor safety partly triggered by the
Three Mile Island incident, which was more of a
perceived than real disaster, (b) the question of the
disposal of radioactive waste, and (c) other public
perception issues which concerns are still in the process
of being debated and hopefully, resolved.
Nevertheless, today in the USA nuclear power plants
produce around 20% of the nation’s electricity, second
only to coal which produces around 51%, followed by
natural gas at around 17%, hydro at around 5.6%,
petroleum at around 3.4%, and solar wind and other
renewable sources at around 2.1%. In fact, in the year
2000 US nuclear power plants generated a record 753.9
billion KWh of electricity. That is to say on average the
electricity in one out of every five homes and businesses,
in the US, comes from a nuclear power plant!
At the present time some 31 countries world wide are
operating some 441 nuclear power plants generating
electricity which in the year 2000 produced about 16%
of the entire world’s electrical energy! Today 17 of these
31 countries rely on nuclear energy to supply at least one
quarter of their total electricity needs. In 10 countries
some 29 new nuclear reactors are currently under
construction and 6 new plants began producing elec-
tricity in 2002.
ARTICLE IN PRESSJ. Masefield / Radiation Physics and Chemistry 71 (2004) 8–1510
Let us now consider the growing global need for
electrical power.
Do you know in the year 2000 the world population
reached some 6.1 billion? And it is estimated that
population could climb as high as 10 billion by the year
2050 according to ‘‘World Population Prospects: The
year 2000 Revision’’. In fact, children born in the 1950s
are the first generation to see the world’s population
double in their lifetime.
Can you imagine that of the world’s population there
are still approximately 1.6 billion people who have no
access to electricity?
As the world population continues to grow at around
1.3%, that is to say around 220,000 people per day
mostly in countries that have limited access to electricity
it is estimated that by the year 2020 an additional 2
billion people, will need electricity!
However, in view of the fact that in the minds of some
people the concept of nuclear power plants still
generates concerns and misguided fear as to their safety
and environmental impact let us consider some of the
real facts:
* Nuclear power in comparison with traditional fossil
fuel energy sources has in fact the lowest impact on
the environment.* Nuclear power plants, produce no controlled air
pollutants, and greenhouse gases.* Over a 25 year period ending in 2001 nuclear power
plants avoided the emission of 70.3 million tons of
sulfur dioxide, 35.6 million tons of nitrogen oxide,
and nearly 3 billion tons of carbon dioxide!* In Europe, nuclear energy plays a vital role in helping
the EU meet its Kyoto protocol commitment to
significantly reduce the emission of greenhouse gases.* According to Frederik Bolkestein, who is the EU
Commissioner of the Internal Market and Taxation
Directorate:
the current use of nuclear energy avoids 312 million
tons of carbon dioxide per year, which is 7% of all
greenhouse gases emitted in the Union.
* Also, throughout the nuclear fuel cycle the relatively
small volume of waste by-products actually created is
carefully contained, packaged, and safely stored.* As a result the nuclear energy industry is, in fact, one
of the only industries established since the industrial
revolution that has accounted for all of its waste
preventing adverse impacts on the environment.* Also, contrary to the claims made by those who
criticize the safety of nuclear power plants, for years
America’s nuclear energy industry has ranked
amongst the safest places to work in the United
States. For example:
In the year 2000 its industrial safety accident rate,
which tracks the number of accidents, that resulted in
lost work time or restricted work by facility was 0.26
per 200,000 worker-hours. By comparison, the
accident rate for US private industry was 3.1 per
200,000 worker-hours, in the year 1998!
After more than 20 years and over $4 billion spent on
scientific research and construction, last summer the US
Congress approved ‘‘Yucca Mountain’’ in Nevada as
America’s first permanent repository for radioactive
waste.
The use of this site, however, is still temporarily held
up for political rather than scientific reasons. As recently
stated by President Bush:
The use of Yucca Mountain as a disposal site is based
on sound science and compelling national interest.
Also, Vice President Cheney recently stated that:
If you’re really concerned about global warming and
carbon dioxide emissions then we need to aggres-
sively pursue the use of nuclear power which we can
do safely and sanely, but for some 20 years now has
been a big no-no politically. Some of the same people
who yell the loudest about global warming are also
the first ones to scream when somebody says: ‘Gee,
we ought to use nuclear power’.
Both President Bush, and Vice President Cheney’s
views were confirmed by the findings of researchers with
the Massachusetts Institute of Technology (MIT),
and Harvard University in July of this year in what
is recognized as ‘‘the most comprehensive interdisciplin-
ary study ever conducted on the future of nuclear
energy’’.
The Study concluded that nuclear power should be
pursued as a long term option along with other options
and in it, Dr. John Deutch, an MIT Chemistry Professor
stated:
Taking nuclear power off the table will prevent the
global community from achieving long term gains in
the control of carbon dioxide emissions.
In fact, the carbon dioxide emissions avoided by US
nuclear power plants alone are equivalent to carbon
dioxide emissions from approximately 130,000,000 cars
which is an astounding 94% of the total number of cars
in the US!
However, as is often the case with so many worth-
while endeavors the nuclear industry has its fair share of
challenges. Some of these which require further resolu-
tion are:
* Issues associated with the high up front capital costs
of nuclear power reactors, reactor safety, the ques-
tion of waste disposal and proliferation.
ARTICLE IN PRESSJ. Masefield / Radiation Physics and Chemistry 71 (2004) 8–15 11
In a number of countries the nuclear industry is facing
up to these challenges by investing in the design of
advanced reactors with higher efficiency, lower cost, and
further improved safety.
Also, the US Congress is currently considering a
sweeping energy bill that includes construction loan
guarantees for up to 50% of the cost for six or seven new
nuclear plants coupled with power purchase guarantees.
The intent is to add 8400 megawatts of electricity
production capacity.
Thus, it would seem that Edward Teller’s visionary
statement made three decades ago is as true today as it
was then, namely that in order to meet mankind’s
growing need for energy we must utilize appropriately
all of the vital energy sources provided from ‘‘Heaven
and Earth’’, as suggested by the title of his book, from
fossil fuels and nuclear to hydro, solar, geothermal and
wind! We need to fine tune and further refine each
technology so that our energy producing technologies
are kinder to our environment as well as plentiful and
cost effective.
With these thoughts in mind, I would now like to
move on to our own industry—Ionizing Radiation
Processing!
To briefly review how we have come to where we are
today, in July of 1947 the Canadian government’s
nuclear research establishment commissioned its own
Nuclear Research Experimental Reactor, NRX, which
was a heavy water natural uranium reactor located at
Chalk River, Ontario. Aside from its planned nuclear
research activities whose primary function was to
support the design and development of electricity
generating nuclear power plants, NRX, began produ-
cing small quantities of the radio-isotope Co-60 for use
in the treatment of cancer by exposing the non radio-
active element Co-59 to neutron bombardment in the
flux flattening adjuster rod positions in the reactor.
It just so happened that the neutron flux that resulted
from this heavy water natural uranium reactor design
meant that NRX could produce high specific activity
Co-60 more efficiently and a lower cost than any other
reactor in existence at the time.
Indeed, one of the routine activities at NRX became
the production of high specific activity Co-60 for cancer
treatment.
Subsequently, in 1952 the Canadian government
created a new Crown Corporation, ‘‘Atomic Energy of
Canada Ltd. (AECL)’’, to take charge of the develop-
ment of electricity generating power reactors and to
manage its nuclear research.
Additionally, a commercial products division of
AECL was formed now known as MDS Nordion,
dedicated to finding and developing medical and
industrial applications for radio isotopes.
Over the ensuing years the AECL’s Commercial
Products Division, developed, manufactured, and mar-
keted a successful line of Co-60 cancer therapy machines
before going on to develop industrial Co-60 sources and
industrial gamma irradiators.
During 1954, AECL commissioned the more powerful
NRU reactor which had seven times the Co-60
production capacity of NRX and by 1960, the combined
annual production capacity of NRX and NRU was
900,000 curies of Co-60 per year.
Those of us that joined AECL Commercial Produc-
tion Division at that time were pretty excited by this
seemingly large amount of Co-60 and were enthusiasti-
cally engaged in exploring potential useful radiation
processing applications.
In order to stimulate interest in the merits of radiation
processing and to better understand and demonstrate
possible applications of gamma radiation particularly
for the irradiation of food for shelf life extension and
sprout inhibition, AECL Commercial Products Division
built in 1960 a truck mounted mobile Co-60 gamma
irradiator with a 40,000 curie Co-60 source to tour the
provinces of Canada irradiating a variety of food and
other products.
I recall that it was in the Maritime Provinces, New
Brunswick to be precise, that the now oft repeated
incident occurred when a local farmer arrived at the
irradiator just as we were transitioning from the
irradiation of potatoes to the irradiation of carrots.
As a result, for a brief period carrots were going into
one end of the irradiator and potatoes were emerging
from the other end. The amazed farmer, commented
that, radiation must be ‘‘powerful stuff’’ and pointed
out that there was a shortage of lettuce that year and
could we turn those carrots into lettuce instead of
potatoes!
Well, the industry has progressed a long way since
then and today upwards of 30 million curies per year are
being produced annually in nuclear electrical power
generating reactors in several countries. The two main
suppliers being Canadian based MDS Nordion, and
UK-based REVISS (Puridec) Services.
There are now some 163 commercial Co-60 irradia-
tors operating in some 47 countries containing approxi-
mately 240 million curies of Co-60. Of these, 54
irradiators containing approximately 132 million curies,
that is to say, well over 50% of the installed base are in
operation in 18 States of the USA.
In fact, approximately 80% of the installed industrial
Co-60 base in North America is being used to sterilize
single-use medical devices amounting to some 200
million cubic feet of products per year.
Of the 240 million curies of Co-60 currently in service
replenishment for decay alone requires annual produc-
tion of 29 million curies. Overall growth in demand for
the radiation sterilization of single-use medical devices
continues in the United States at a rate of approximately
7% per year. Assuming a modest overall growth in
ARTICLE IN PRESSJ. Masefield / Radiation Physics and Chemistry 71 (2004) 8–1512
demand of 3–5%, worldwide would add another 7–12
million curies per year to the global requirement.
It is important therefore that our segment of the
industry effectively and regularly conveys to govern-
ment, management of the nuclear power utilities, and
society at large the vital role that reactor produced
isotopes, especially Co-60, play in bringing countless
benefits to our lives.
It is worthy to note that, since the 1960s, over 600
million curies of Co-60 have been safely shipped
worldwide.
With respect to applications, one of the first and what
has become one of the largest single industrial uses of
ionizing radiation is the gamma radiation sterilization of
medical products.
The drivers of this technology, which have withstood
the test of time are:
1. Firstly, the effectiveness of the process resulting from
the ability of gamma radiation to easily penetrate
relatively large thickness of dense product. This
permitted great flexibility in product and package
design.
2. Secondly, the inherent simplicity of the gamma
irradiation process.
3. Thirdly, the inherent reliability of gamma
irradiators.
4. Fourthly, the absence of residuals in irradiated
product.
5. Finally, the process is cost competitive.
Increasingly, in the case of North America, as the
network of contract Service irradiation facilities
continues to strategically expand the need for
healthcare companies to build in-house irradiators
has diminished significantly and there is a trend
towards phasing out some existing in-house irradia-
tors in favor of using contract facilities.
With respect to the design of gamma irradiators
themselves, the principles adopted in the first
industrial irradiators have stood the test of time and
are still evident in the irradiators being built today,
namely:
* Welded, double encapsulated Co-60 sources.* A water filled source storage pool (usually about 23
feet deep).* Multiple layers of product overlapping the source in
order to maximize the amount of radiation energy
absorbed in the product.* Vertical and horizontal integration of the product
around the source to achieve optimum absorbed dose
uniformity. And* A biological shield made of standard density concrete
with a labyrinth entrance, to facilitate uninterrupted
production.
Irradiator design changes that are taking place
currently focus on improving the cost effectiveness of
the irradiation process, speeding up the turn time,
improving the dose uniformity ratio within product
being sterilized, and further improving the operational
reliability of the process.
These changes include:
* An increase in the average design capacity of
irradiators from around 1 million curies in 1964 to
between 3–7 million curies per irradiator today.* Improvements in the design of irradiator product
conveyor systems to further increase energy absorp-
tion efficiency within the product, improve dose
uniformity, ease of maintenance, and machine
reliability.* Further automation of product handling systems in
warehouse product staging areas to reduce labor
costs.* Further computerization of irradiator controls in-
cluding the inclusion of irradiator fault diagnostic
systems, and after 9/11/2002, further improvements
in irradiator security and irradiator safety interlock
systems.
With respect to the sterilizing process itself, I had the
privilege of co-chairing the Association for the Ad-
vancement of Medical Instrumentation (AAMI) Radia-
tion Sterilization Committee that was charged with
developing ‘‘Process Control Guidelines for the Ster-
ilization of Medical Devices’’ from its inception in 1974
until after its work was accepted in 1994 as the
International Standard, ISO11137.
This standard has in the intervening period been
further reviewed and the latest revisions will be
presented during the course of this Conference including
techniques for establishing a sterilization dose for
products with low average bio-burden.
Continuing efforts are being made firstly to optimize
the selection of sterilizing dose, secondly to more
accurately determine the dose distribution within
products using mathematical modeling of dose distribu-
tion, and thirdly to use new and more accurate
dosimetry systems. Mathematical models have been
developed for gamma, high energy electron beam and X-
ray irradiation facilities.
I hope that the next step in the evolution of dose
setting methods will include a comprehensive risk
analysis which relates Sterility Assurance Level
(SAL) to the end use of the product as it relates to
patient safety and re-examine the current practice
of tying rational dose setting methods to an arbitrary
Sterility Assurance Level (SAL) of 10–6 regardless of the
end use of the product. By so doing we would expect in
many cases to see sterilizing doses lowered significantly
without any compromise in patient safety which can
ARTICLE IN PRESSJ. Masefield / Radiation Physics and Chemistry 71 (2004) 8–15 13
further expand the range of products that can be
radiation sterilized and improve process cost effective-
ness.
Now, I would like to briefly discuss the status of High
and Low Energy Electron Beam Accelerators.
Over the last 50 years advances made in particle
accelerator technology have resulted in the wide scale
global industrial use of both high and low energy
electron beam accelerators and more recently to the
limited industrial use of X-rays.
Indeed, there are now over 1000 high-energy e-beam
machines installed around the world for industrial
applications.
The range of uses encompass:
1.
First, the cross linking of polymeric materials toenhance their Physical properties. Some examples of
radiation cross linking include:
�
The cross linking of the PVC Jacketing of wireand cable to enhance thermal stability, increase
tensile strength, and other physical properties.
�
The cross linking of tubing to impart heat shrinkmemory, increase tensile strength, and service
temperature.
�
The cross linking of rubber compound compo-nents to improve their mechanical properties, and,
�
The cross linking of plastic parts and pellets toimprove their physical properties and convert
thermo plastics to thermo sets.
2.
Second, in the area of curing some examples includethe e-beam radiation curing of advanced composites
for use in the aircraft, aerospace, sporting goods,
and, transportation industries.
Another significant development in the past year
has been the availability of approved e-beam curable
laminating adhesives for flexible packaging applica-
tions. This opens up a potentially large application in
the packaging of food products where conventional
ultra violet (UV) cured adhesives cannot be used
because of the potential for product adulteration
from any un-reacted photo initiator associated with
the UV curing process.
Similarly, the development of Food and Drug
Administration (FDA) complying flexographic inks
and coatings has opened up new opportunities for
high speed converting processes where a single e-
beam curing station for example, may cure inks,
topcoats, and laminating adhesive at the same time
with great economic advantage and energy economy.
Other growing electron beam applications include:
�
The terminal sterilization of heat-sensitive low-density medical products.
�
The irradiation of up to 3-inch thick packagedselected fresh and frozen meat products to
eliminate pathogenic organisms and the irradia-
tion disinfestations of certain tropical fruits.
�
A major application for low-energy e-beam is thetreatment of flue gases for controlling air pollu-
tion. This process developed in Japan, Germany,
and Poland allows simultaneous removal of
nitrogen and sulfur oxides (NOx and SOx) with
high efficiency and the byproducts generated can
then be applied as fertilizer. Two industrial
installations using this technology have been
constructed one in China and the second in
Poland.
In the area of electron beam equipment, there are 3
major types, namely:
1. Direct current (DC) accelerators: Energy range from
0.1 to 5.0Mev and power up to 300 kW.
2. Microwave linear accelerators (S and L band): With
energies ranging from 2.0 to 25Mev, and beam
power up to 150 kW.
3. Radio frequency accelerators: With energies ranging
from 1.0 to 10Mev and beam power up to 700 kW.
The industrial market for accelerators is being driven
by the need for:
* Smaller more compact self-contained irradiation
systems.* Lower up front equipment capital costs.* Machines with higher beam power levels for high
throughput cross linking and for high penetration X-
ray applications.
Further development of X-ray targets is ongoing in
the US and Europe for use with 5–10MeV high-power
electron accelerators with the goal of enabling the
sterilization of higher-density medical products and the
processing of pallet quantities of food products.
High electron beam powers at low voltage have been
successfully developed to provide 10,000 kGy meters per
minute (mpm) from single units at product widths of up
to two meters. These systems support the 300–400mpm
speeds sought in most ‘‘converting’’ applications.
Continuing progress is being made in the utilization of
low-voltage self-shielded processors for the disinfesta-
tion and sterilization of particulates. These units have
been used to disinfect seed while retaining germ vitality
and several papers to be presented at this Conference
address this application which is important to plant
pathogen control.
Additionally, progress is being made in the develop-
ment of modular sealed electron beam tubes working at
voltages around 100KV which show promise for low
power use particularly in the surface sterilization of
medical devices and pharmaceutical packaging materials
used in conjunction with aseptic filling operations.
ARTICLE IN PRESSJ. Masefield / Radiation Physics and Chemistry 71 (2004) 8–1514
Now, let us briefly review the status of the long
debated subject of Food Irradiation.
Until recently, the only food product that has been
routinely irradiated in larger quantities has been spices
of which an estimated 100 million pounds are being
irradiated annually to eliminate harmful pathogens. The
majority of spices, however, are still being fumigated
with ethylene oxide.
Irradiation is starting to be used commercially as a
phytosanitary treatment on imported tropical fruits and
some vegetables to replace methyl bromide and reduce
the use of vapor heat treatment as well as hot water dip
which adversely affects product quality.
With small quantities of certain irradiated meats and
fruits now in several thousand stores across the USA it is
perhaps fair to ask the question: Food Irradiation, Why
Now?
Though it is generally recognized that the USA has
the safest food supply in the world the number of food-
borne diseases yearly remains staggeringly high.
Though estimates vary one authoritative estimate is
that annually there are 76 million illnesses, 325,000
hospitalizations, and 5000 deaths from food
poisoning.
US Government agencies have identified the primary
preventable food safety hazards as microbial infections
from a growing emergence of antibiotic resistant
pathogens, food allergens, and certain pesticides and
chemical additives.
Today, centralized food production has in addition
created even more favorable conditions for the dis-
semination of bacteria.
Another contributing factor in the increase in food-
borne illnesses is that we live in a global economy with a
global food supply and porous borders. Additionally,
we have become accustomed to enjoying fresh produce
year round imported from around the world.
In the year 2000 alone the USA imported nearly $49
billion worth of food products including about $8 billion
worth of fruits, vegetables, and juices many from places
with compromised standards of water quality and
sanitation. The level of imports has expanded way
beyond any reasonable inspection capacity. It is not
surprising, therefore that imported foods have caused
notable food-borne disease outbreaks.
As you may know in 1994 Isomedix petitioned the
FDA to authorize the irradiation of fresh and frozen red
meat to enable its selected use were needed to improve
food safety.
Shortly, after a massive recall of E.coli 0157H7
contaminated ground beef in 1997, which put the
billion dollars a year Hudsons Food Company out of
business, almost overnight the Isomedix Petition was
approved.
In issuing their ruling after rigorous scientific review
the FDA explained that the process:
Will not present toxicological hazards, will not
present microbiological hazards, and will not affect
the nutritional adequacy of such products.
Since it is generally accepted however, that by testing
alone it is not possible to prove that any food process is
perfectly safe, public willingness to accept a new food
process depends on how well it meets the value and fear
concerns of the consumer whether such concerns are real
or perceived. In essence, some claim that science should
take a back seat to fear whether that fear is justified or
not.
Well, history has witnessed that this situation is not
new. As you know, amongst many other fear-driven
challenges that we have had to overcome in advancing
technology over the decades, it took 50 years for
pasteurized milk to be accepted. And, when electricity
was first introduced it was considered to be very
dangerous and something that should be avoided at all
cost by many people!
Thus, even though it is generally recognized that the
estimation of safety and nutritional adequacy is a
scientific question and therefore a legitimate activity of
scientific agencies, the acceptability of any new food
process becomes a consumer and political question.
Amongst many encouraging reports by credible
authorities one recent report quoted the President of
the Food Marketing Institute as stating:
Food irradiation is one safety tool whose time has
come!y . As industry, we must also have the courage
to support irradiated food products in the market
placey . We must not let those who are afraid to let
consumers make their own judgments use misinfor-
mation and scare tactics to win arguments they
would lose on the scientific merits of the argument.
Certainly, the use of food irradiation technology is
not the panacea for all food-borne illnesses! However,
there are certain selected food safety problems that can
most effectively be resolved by the use of this valuable
technology.
Food irradiation has been meticulously studied by
scientists around the world for more than half a century
and surely it is high time that food irradiation takes its
place amongst the panoply of accepted food safety
processes.
Accordingly, recognizing the sophistication of today’s
consumers we should be given the choice of being able to
purchase irradiated food products in those instances
where it is clear that irradiation improves food safety.
This is happening slowly in the US where consumers
now have the choice of buying certain irradiated meat
and fruit products in several thousand stores across the
country.
In addition, the Food and Agriculture Organization
(FAO) of the United Nations (UN) estimated that
ARTICLE IN PRESSJ. Masefield / Radiation Physics and Chemistry 71 (2004) 8–15 15
worldwide over 25% of all food production is lost after
harvesting to insects, bacteria, rodents, and sprouting.
Food irradiation promises to play a role in cutting these
losses at the same time reducing the world’s dependence
upon pesticides and other chemical treatments.
Other growing applications of the technology include
the radiation processing of a wide range of consumer
products from personal hygiene products and children’s
toys to the microbial reduction of cosmetic ingredients
to mention just a few. In addition, there is phytosanitary
treatment for fresh imported tropical fruits and vege-
tables from Hawaii and other tropical fruit growing
countries, and insect pest control and insect eradication
using the sterile male technique.
Ladies and gentlemen, in summary it is apparent that
ionizing radiation applications have grown vastly over
the past decades to where they are playing an increas-
ingly important role and impact a substantial part of our
every day lives!
In the area of healthcare ionizing radiation is put to
use on a daily basis in the diagnosis of illnesses (radio-
pharmaceuticals), in the treatment of cancer, and in the
sterilization of billions of medical devices annually to
render them safe for their intended use.
It is also used to sanitize and reduce the microbial
bioburden on a wide range of consumer products
from food packaging and baby products to neutraceu-
ticals.
It is being used to improve the physical properties of a
wide range of materials used by the auto-
motive, aerospace, telephone, and consumer products
industries.
In the agricultural sector, it is being used, as a
phytosanitary treatment. Now, it is beginning to be used
on a selective basis to make our food supply safer extend
its fresh shelf life and reduce food spoilage losses.
This is a dynamic industry! At this Conference we can
inspire each other by exchanging ideas and sharing in
the results of ongoing research and information about
the commercial application of the technology so that we
can return to our homes refreshed with renewed
enthusiasm new ideas and with the ‘‘will’’ to further
expand the technology around the world!
This is an industry that many of you gathered here
have helped to shape and expand for the benefit of
mankind, to improve the quality of our daily lives, and it
is an industry that each and every one of us should be
proud to be a part of!!!
