Radon: The Leading Environmental Cause
of Cancer Mortality in the U.S
R. William Field, PhD, MS
College of Public Health
Department of Occupational and
Environmental Health
Department of Epidemiology
University of Iowa
What Is Radon –222 (radon)?
• Radon is a gas
• It is naturally occurring
• You can not see or smell it
• It enters buildings primarily from the
soil
Uranium
Radium
Radon
1,600 years
4.5 billion years
3.8 days
Reading Prong
U.S. Radon Potential
Based on geology and
surveys
Expected closed building
radon (pCi/L):
Zone 1: 4.0 and above
Zone 2: between 2.0 & 4.0
Zone 3: 2.0 and lower
RISK PERCEPTION: Why is the
evidence often ignored or not accepted ?
• Invisible, odorless, colorless
• Naturally occurring outdoors
• Can not link an individual death to radon exposure
• Long latency period
• Not a dread hazard
• Cancers occur one at a time
• Lung cancer does not occur in children
• Voluntary risk
• Lack of press – no sensational story
• No sensory reminders to repetitively stimulate us to think
about it
Stanley Watras at the
Limerick Nuclear Power
Plant, Christmas 1984
"I just thank God that if it was
going to be anybody living in that
house, it would be me, somebody
who could, through their work
activities, discover the situation,”
Philadelphia Inquirer March 20, 1985
Radon
Decay
Products
Lead-210
Polonium-214
Bismuth-214
Lead-214
Polonium-218
Radon-222
b,g
a,g
a,g
a,g
b,g
Lead-206
Polonium-210
Bismuth-210 b,g
a,g
b,g
22 yrs
4 day
3 min
27 min
20 min
0.2 ms
5 day
138 day
Stable
Po-218 and Po-214
deliver the majority
of radiation dose to
the lung.
Why are radon decay products a health concern?
These particles are easily inhaled and deposited in the lungs where they can damage sensitive lung tissue.
Radon Decay Products
Radon
Radon
Alpha Decay
4He nucleus ejected from 222Rn nucleus
+2
4He + 218Po
+
+
+
+
+
+
+
+
+
Radon - 222
What Happens When Radon Decay
Products Are Inhaled ?
• Highly radioactive
particles adhere to
lung tissue, where
they can irradiate
sensitive cells.
• Radiation can alter
the cells, increasing
the potential for
cancer. Double Strand Breaks
Ionizing radiation can directly and
indirectly damage DNA
Alpha
Particle
Defects in tumor
suppressor genes – p53
At risk individuals–GSTM1
(glutathione S-transferase M1)
Annual Effective Dose Equivalent to
Member of the U.S. Population
NCRP 93 (1987)
Other
< 1%
Radon
55%
Consumer
Products
3%Nuclear
Medicine
4%
Cosmic
(Outer Space)
8%
Terrrestrial
(Rocks & Soil)
8%
Internal
(Inside Human
Body)
11%
Medical X-rays
11%
Other Includes:
Occupational 0.3%
Fallout < 0.3%
Nuclear Pow er 0.1%
Miscellaneous 0.1%
Natural 82%
Artificial 18% Natural (mrem) Radon 200
Cosmic 27
Terrestrial: -external 28
-internal 39
Artificial (mrem) -Diag. X-rays 39
-Nuc. Med. 14
-Consumer Pro. 10
-Other ~1
TOTAL ~360
From NCRP Report No. 160, “Ionizing
Radiation Exposure of the Population of the
United States” (2009)
"Statistics are
people with the
tears wiped
away."
Irving Selikoff
Studies of Underground Miners
Cohort Studies (15) of Radon-Exposed Miners
Radium Hill
Czech Republic (2)
China
Ontario
Port Radium
Beaverlodge
Newfoundland France
New Mexico
Sweden
Colorado
Cornwall E. Germany
Brazil
National Academy of Sciences
BEIR VI (1999): Pooled Analysis of 11 Miner Studies
Study Lung ca P-yrs
China 980 175,342
Czech Republic 705 106,924
Colorado 336 87,821
Ontario 291 380,719
Newfoundland 118 48,742
Sweden 79 33,293
New Mexico 69 55,964
Beaverlodge 65 118,385
Port Radium 57 52,677
Radium Hill 54 51,624
France 45 43,962
Total 2,787 1,155,453
Mean: WLM = 164, Duration=5.7 y * With smoking info
Lubin et al. 1995
0<2
5
25-4
9
50-9
9
100-
199
200-
399
400-
799
800+
0
200
400
600
Num
ber
of lu
ng c
ancer
cases 493
602567
438
222
129
226
Working Level Months
110
Radon Exposure of Lung Cancer Cases in Miners
<5 pCi/L
<10 pCi/L
<20 pCi/L
Reside 25Y @
Dose-
Response
in Miner
Studies (I) 0 200 400 600 800 1000
0
1
2
3
0 200 400 600 800 10000
2
4
6
8
0 500 1000 1500 2000 25000
5
10
15
20
25
0 50 100 150 200 2500
1
2
3
4
5
China
Czechoslovakia
Colorado (<3.2K WLM)Re
lative
ris
k
Cumulative WLM
Ontario
Lubin et al. 1995
NRC BEIR VI, 1999
Dose-
Response
in Miner
Studies
(II)
0 1000 2000 30000
20
40
60
80
100
0 50 100 150 2000
2
4
6
8
0 500 1000 1500 2000 25000
20
40
60
80
0 50 100 150 2000
5
10
15
Newfoundland
Sweden
New Mexico
Re
lative
ris
k
Cumulative WLM
Beaverlodge
Dose-
Response
in Miner
Studies (III)
0 500 1000 1500 20000
2
4
6
8
0 20 40 60 80 1000
5
10
15
0 200 400 6000
2
4
6
8
Port Radium
Radium Hill
France
Re
lative
ris
k
Cumulative WLM
National Academy of Sciences
BEIR VI 1999
• Risk estimates based
primarily on radon-
exposed miners
• Estimated 18,600 lung
cancer deaths each
year in the U.S. from
residential radon
exposure
In 2003, the EPA
updated the BEIR VI risk
estimates to 21,000
radon-related lung
cancer deaths each year
in the United States.
http://www.epa.gov/radon/risk_assessment.html
CANCER MORTALITY - 2012
CANCER TYPE ESTIMATED U.S. DEATHS/YR
1. Lung and Bronchus 160,340
2. Colon and Rectum 51,690
3. Breast Cancer 39,920
4. Pancreas 37,390
5. Prostate 28,170
6. Leukemia 23,540
>>> Radon Induced Lung Cancer 21,000
7. Liver and Bile Duct 20,550
8. Non-Hodgkin Lymphoma 18,940
9. Ovary 15,500
10. Esophagus 15,070
11. Urinary Bladder 14,880
12. Kidney and Renal Pelvis 13,570
13. Myeloma 10,710
14. Stomach 10,540
Published Online: 27 May 2009
Copyright © 2009 American Cancer Society
CA: A Cancer Journal for Clinicians Volume 62, Issue 1, pages 10-29, 4 JAN 2012 DOI: 10.3322/caac.20138 http://onlinelibrary.wiley.com/doi/10.3322/caac.20138/full#fig4
Epidemiologic Residential
Radon Studies
Dose Response Model
Dose
Adve
rse H
ealth E
ffects
Linear Non-Threshold Theory
Observed
Effects
Radon-Exposed
Miners
Residential Radon Case-Control
Around the World European Studies 13 Studies from 9 Countries
• Austria • Czech Republic • Finland [nationwide] • Finland [south] • France • Germany [eastern] • Germany [western] • Italy • Spain • Sweden [nationwide] • Sweden [never smokers] • Sweden [Stockholm] • United Kingdom
• Total 7,148 cases and 14,208 controls
North American Studies • 7 Studies from 2 countries:
• New Jersey • Winnipeg • Missouri I [non-smoking
women] • Missouri II [women] • Iowa • Connecticut • Utah-South Idaho
• Total 3,622 cases and 4,966 controls
EuropeChina
North America
AustriaCzech Republic
FinlandFinland (south)
FranceGermany (eastern)Germany (western)
ItalySpain
SwedenSweden (never-smkrs)
StockholmUnited Kingdom
GansuShenyang
New JerseyWinnipegMissouri-IMissouri-II
IowaConnecticut
Utah/South Idaho
0.5 1.0 1.5 2.0
Study
OR at 148 Bq/m3
Cases/Cntls
511/862
963/949
413/614
512/553
538/1183
738/738
480/442
285/338
768/1659
960/3126
196/375
258/487
960/3126
156/235
384/405
1323/2146
945/1516
571/1209
160/328
881/1435
171/173
183/188
4155/5341
1053/1997
7148/13668
Residential Radon
Studies
Odds Ratios
at 4.0 pCi/L (150 Bq/m3)
China: Lubin 2004
Eur: Darby et al. 2004, 2006
NA: Krewski et al. 2005, 2006
OR at 4.0 pCi/L
New Jersey, Missouri I, Canada, Iowa, Missouri II, a combined study from Connecticut, Utah and S. Idaho
Shenyang, China, Stockholm, Sweden,
Swedish nationwide, Winnipeg, Canada, S. Finland, Finnish nationwide, SW England, W. Germany, Sweden, Czech Republic, Italy-Trento, Spain, Austria, France, China - Gansu Province, E. Germany
Pooled Analyses Agreement at 3 pCi/L ??
Continuing support was provided by the
National Cancer Institute and U.S. EPA
0 5 10 15 20
0
1
2
3 IA CT
MO-1 UT
MO-2 Winn
NJ-1
Od
ds
ra
tio
Radon concentration (x), pCi/L
Results of All
Radon Studies
of Lung
Cancer
0 5 10 15 20
0
1
2
3
Od
ds
ra
tio
Radon concentration (x), pCi/L
NA pooled RRs
EPA
Gansu
Shenyang China pooled RRs
Pooled European RRs
Pooled miners
Occupational Radon Exposure – also a health risk
Occupational Exposure to Radon
– Very Common
• Mine workers, including uranium, hard rock, and vanadium
• School Employees
• Workers remediating radioactive contaminated sites, including uranium mill sites and mill tailings
• Workers at underground nuclear waste repositories
• Radon mitigation contractors and testers
• Phosphate fertilizer plant workers
• Oil refinery workers
• Utility tunnel workers
• Subway tunnel workers • Construction excavators • Power plant workers, including geothermal power
and coal • Employees of radon health mines • Employees of radon balneotherapy spas
(waterborne radon source) • Water plant operators (waterborne radon source) • Fish hatchery attendants (waterborne radon
source) • Employees who come in contact with
technologically enhanced sources of naturally occurring radioactive materials
• Incidental exposure in almost any occupation from local geologic radon sources
• Farming related activities
Other types of cancer may be associated with protracted
radon exposure
Summary
• Radon is a global public health concern.
• The residential radon studies have provided direct evidence that prolonged residential radon is one of our leading public health risks and major cause of cancer mortality.
• Radon is our leading environmental cause of cancer mortality in the United States and seventh leading cause of cancer mortality overall.
Global Perspective on Radon WHO’s International Agency for Research on Cancer - Monographs
on the Evaluation of Carcinogenic Risks to Humans. Volume 43.
Man-made Mineral Fibres and Radon. Summary of Data Reported
and Evaluation (1988)
• Albania
• Argentina
• Austria
• Belgium
• Brasil
• Bulgaria
• Canada
• China
• Czech Republic
• Finland
• France
• Romania
• Russian Federation
• Serbia
• Slovenia
• South Korea
• Spain
• Sweden
• Switzerland
• Turkey
• USA
• Ukraine
• United Kingdom
• Georgia
• Germany
• Greece
• Hungary
• India
• Ireland
• Italy
• Japan
• Lithuania
• Luxembourg
• Norway
• Poland
WHO-IRP National Partners
http://www.who.int/ionizing_radiation/env/radon
WHO Handbook on Indoor Radon
THE WHO INITIATIVE TO REDUCE LUNG
CANCER RISK AROUND THE WORLD
Availability of WHO Handbook
• WHO Handbook on Indoor Radon: A Public Health Perspective:
http://www.who.int/ionizing_radiation/env/radon/en/index1.html
• WHO Radon Webpage: http://www.who.int/ionizing_radiation/env/radon/en/index.htm
l
Radon in Schools
“A nationwide survey of radon levels in schools
estimates that nearly one in five has at least one
schoolroom with a short-term radon level above the
action level of 4 pCi/L (picoCuries per liter) - the level
at which EPA recommends that schools take action to
reduce the level. EPA estimates that more than seventy
thousand (70,000) schoolrooms in use today have high
short-term radon levels.”
“EPA's national survey of schools
produced some alarming results about
concentrations in our children's
classrooms. Public awareness must be
raised about the hazards of radon to
hasten efforts to reduce the danger. All
schools must be tested to determine if
there is a problem, and schools must
inform parents of the results. We cannot
ignore this problem."
Kathryn Whitfill, National PTA
President.
Radon Testing and Mitigation
“Closed House” Conditions For All Short-Term Tests
All exterior doors and windows closed, except for normal entry and exit
Internal-external air exchange systems off Total internal recycle is allowed
Combustion or make-up air must not be closed
Permanent radon mitigation systems remain on
Bedroom
YES
Bedroom
YES
Kitchen
NO
Bedroom
YES
Closet NO Bathroom
NO
Living Room
YES
Garage
NO
Test Location Depends on Purpose
Suitable for
Occupancy
Non-Real Estate
Real Estate
Choose
occupied room
Keep away
from drafts and
moisture
Lowest lived in
Lowest lived in
Test Placement Within A Room
• 3 feet from windows or exterior doors
• At least 20 inches above floor
• 4 inches from other objects
• Where it won’t be disturbed
12 inches min. 3 feet
min.
20 inches min.
A Common Real Estate Testing Method 2 Simultaneous Tests
Two Simultaneous tests
Mitigation
Recommended
No Mitigation
Recommended
Average of Both
Tests > 4.0 pCi/L
YES NO
Homes With High Radon Concentrations
Can Be Remediated
Active soil depressurization is a means of
creating a vacuum beneath a slab or plastic
sheet and collecting the radon before it enters a
building.
Can’t We Just Seal The Cracks?
• Radon can enter through very small openings.
• Without affecting house pressures, sealing is not a stand-alone technique.
Suction Point For Slabs And Basements
• Hole cut through slab
• Pit dug out
• PVC pipe connected to
hole
• Pipe routed to fan
• May require more than
one suction point
System Depressurization Fan
• Installed in attic, garage, or outside
• Quiet
• 40 - 90 watt fan runs continuously
• 11 year expected life
System Discharges Away From Building Openings
• Discharge should be high to
avoid radon entering building
– Minimum of 10 feet above grade
– 10 feet from openings, 2 feet
below discharge
– Above eave
• Rain cap not recommended
• 1/4 inch bird screen
US EPA Mitigation Standards
http://www.epa.gov/iaq/radon/pubs/
New Homes Can Be Built With Radon Control Systems
RADON VENT
RADON
VENT
Radon: The Leading Environmental Cause
of Cancer Mortality in Iowa and the Midwest
R. William Field, PhD, MS
College of Public Health
Department of Occupational and
Environmental Health
Department of Epidemiology
University of Iowa
CANCER MORTALITY - 2012
CANCER TYPE ESTIMATED U.S. DEATHS/YR
1. Lung and Bronchus 160,340
2. Colon and Rectum 51,690
3. Breast Cancer 39,920
4. Pancreas 37,390
5. Prostate 28,170
6. Leukemia 23,540
7. Liver and Bile Duct 20,550
8. Non-Hodgkin Lymphoma 18,940
9. Ovary 15,500
10. Esophagus 15,070
11. Urinary Bladder 14,880
12. Kidney and Renal Pelvis 13,570
13. Myeloma 10,710
14. Stomach 10,540
15. Melanoma 9,180
Published Online: 27 May 2009
Copyright © 2009 American Cancer Society
CA: A Cancer Journal for Clinicians Volume 62, Issue 1, pages 10-29, 4 JAN 2012 DOI: 10.3322/caac.20138 http://onlinelibrary.wiley.com/doi/10.3322/caac.20138/full#fig4
Outreach activities related to Radon
Iowa Cancer Consortium (ICC)
Clin Chest Med 33 (2012) 681–703
Video on radon geared to health care professionals
Please watch:
http://www.canceriowa.org/BreathingEasier.aspx
http://www.gayandciha.com/obit-display.jhtml?DB=update/obits/dbase&DO=display&ID=1275271457_4483
http://www.canceriowa.org/BreathingEasier.aspx
Your help is needed!
Radon: The Leading Environmental Cause
of Cancer Mortality in Iowa and the Midwest
R. William Field, PhD, MS
College of Public Health
Department of Occupational and
Environmental Health
Department of Epidemiology
University of Iowa