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Lesson 2
Why is radon a health problem?
Slide 2-2
Radon and lung cancer
• Radon is largest source of radiation exposure to general public
• Radon is leading cause of lung cancer among nonsmokers– Only cigarette smoking
causes more deaths from lung cancer
– Radon causes more deaths than secondhand smoke
• Reducing radon in homes could reduce radon-related lung cancers by about 1/3– Home inspectors can
help when they measure radon levels accurately
Slide 2-3
What do you hear people say about radon?
Radon can’t really hurt you. The only problem is
those government alarmists, who are
always trying to scare us about some
environmental hazard. There’s really nothing to
worry about.
Have you heard statements like this?Do you agree with this statement?
Slide 2-4
The facts about radon
• Respected national and international organizations agree that radon causes lung cancer
• All radon studies confirm the connection between radon exposure and lung cancer
• American Lung Association
• American Medical Association
• American Public Health Association
• National Academy of Sciences
• U.S. Centers for Disease Control and Prevention
• U.S. Environmental Protection Agency
• World Health Organization
Slide 2-5
Can you fill in the numbers?
• Annual deaths (1995) from lung cancer: ???
• Total radon-related deaths per year: ???
• Average years of life lost for radon-related lung cancer: ???
Slide 2-6
Radon and lung cancer
• Annual deaths (1995) from lung cancer: 146,400
• Total radon-related deaths per year: 21,000 (14%)
• Average years of life lost for radon-related lung cancer: 17
Slide 2-7
How radon harms the lungs
• Radon gas is inhaled• Radon decay products become
trapped in the lungs• As products decay, some
release alpha radiation• Radiation damages lung tissue• Even very small exposures to
radon can cause lung cancer– No known safe level of radon
• Radon causes no immediate symptoms– Lung cancer usually occurs 5 to 25 years after
exposure• Cancer cells spread to other parts of the body
Slide 2-8
Lung cancer is deadly
• 60% of people with lung cancer die within 1 year of diagnosis
• 70-80% die within 2 years of diagnosis
• The leading cause of cancer death for men and women– Kills more people than
colon, breast, and prostate cancers combined
Slide 2-9
Radon and other health concerns
• No evidence that radon causes other respiratory diseases, such as asthma
• No evidence that children are at greater risk of radon-induced lung cancer than adults
Slide 2-10
Cancer deaths from radon in tap water
Stomach cancer11%
Lung cancer89%
Stomach cancer from swallowing water that contains radon accounts for 11% of those deaths
Lung cancer from breathing radon released by water—as in showering or washing dishes—accounts for 89% of those deaths
Total168 cancer deaths per year
related to radon in water
Slide 2-11
Match cause withestimated deaths per year
21,00017,400
8,000
2,8003,900
0
5,000
10,000
15,000
20,000
25,000
Radon Drunkdriving
Falls in thehome
Drownings Home fires
Cause
Drownings
Drunk driving
Falls in the home
Home fires
Radon
Slide 2-12
Relative risk:estimated deaths per year
21,000
3,900 2,800
8,000
17,400
0
5,000
10,000
15,000
20,000
25,000
Radon Drunkdriving
Falls in thehome
Drownings Home fires
Slide 2-13
Risk factors
• Duration of exposureLonger exposure time =
greater risk
• Levels of radonHigher levels = greater risk
• SmokingIn combination with radon
exposure = greater riskDANGER
Lungs at work
Slide 2-14
Radon concentrations in the air
Picocuries/liter (pCi/L)
Average outdoor 0.4
Average indoor 1.3
Consider fixing the home 2-under 4
Action level: fix the home 4 or above
Action level is based on level that can be achieved technically.
It is not based on health standards. No known level of radon is safe.
Slide 2-15
How common are high radon levels?
EPA estimates that1 in 15 U.S. homeshas a radon concentration at or above the action level of 4 pCi/L Recall: EPA also estimates that reducing
radon in homes could reduce radon-related lung cancers by about one-third
Slide 2-16
Radon risk for people who never smoked
Radon level
(pCi/L)
If 1,000 nonsmokers were exposed to this radon level, the number who could get lung cancer
after lifetime exposure*
Lung cancer risk equal to**
20 36 35 times the risk of dying by drowning
10 18 20 times the risk of dying in a home fire
8 15 4 times the risk of dying in a fall
4 7 The risk of dying in a car crash
2 4 The risk of dying from poison
Slide 2-17
Radon risk for smokers
Radon level
(pCi/L)
If 1,000 smokers were exposed to this level, the number who could
get lung cancer after lifetime
exposure*
Lung cancer risk equal to**
20 260 250 times the risk of dying by drowning
10 150 200 times the risk of dying in a home fire
8 120 30 times the risk of dying in a fall
4 62 5 times the risk of dying in a car crash
2 32 6 times the risk of dying from poison
Slide 2-18
Radon risk comparison
Radon level (pCi/L)
People who never smoked
People who smoke
20 36 260
10 18 150
8 15 120
4 7 62
2 4 32
1.3 2 20
0.4 - 3
Estimated number of people who could get lung cancer
per 1,000 people exposed over a lifetime
See handout 2-1
Slide 2-19
National Health Advisory2005
“Indoor radon is the second-leading cause of lung cancer in the United States …
Breathing it over prolonged periods can present a significant health risk to families all over the country.
It’s important to know that this threat is completely preventable.
Radon can be detected with a simple test and fixed through well-established venting techniques.”
Richard CarmonaU.S. Surgeon General
Slide 2-20
Role play activity
• Two characters– Home inspector– Client
• Action– Home inspector is trying to persuade a
client to have a home tested– Client is reluctant– Home inspector emphasizes health
issues
Slide 2-21
After the activity
• Inspector– What arguments
did you use to convince the client to have home tested?
– Could you have been more persuasive?
• If so, how?
• Client– Did the inspector
convince you?• Why or why not?
– Could the inspector have been more persuasive?
• If so, how?
Slide 2-22
Summary
Radon is known to cause lung cancer
Estimated radon-related deaths each year: 21,000
Reducing radon in homes could reduce radon-related lung cancers by about 1/3
EPA action level: 4 pCi/L
When people breathe in radon and its decay products, radioactive particles get trapped in the lungs– As particles decay, they
damage lung tissue– With long-term
exposure, damage increases risk of lung cancer
Slide 2-23
Summary
Chances of developing lung cancer depend on• Duration of exposure• Level of radon in the home• Smoking
– Greatly increases the risk of developing lung cancer
Slide 2-24
Questions?
• About why radon is a health problem
Slide 2-25
Check your understanding
• See handout 2-2