| Lung
Cancer Risks from Radon
The annual death toll of radon in homes
The "Annual Report on Carcinogens 2000" from
the U.S. Department of Health:
"Based on current exposure and risk estimates,
radon exposure in single-family houses may be a cause
of as many as 20,000 lung cancer fatalities each year."
Estimates from the National Research Council, the National
Academy of Sciences and the U.S. Environmental Protection
Agency as published in the reports "Biological Effects
of Ionizing Radiation" (BEIR VI, 1998).
Radon causes 20,000 additional lung cancer deaths in
the U.S. each year. One radon death occurrs every 25
minutes in the United States.
Indoor radon causes 12.5 percent (10-15%) of lung cancer
deaths. Radon in homes is the second leading cause of
lung cancer.
Radon causes 11% of the lung cancers among smokers
(most die of smoking), but 23% among never-smokers.
Radon is the No. 1 cause of lung cancer among non-smokers.
Comparing radon to other everyday risks
EPA: "Radon in homes causes more deaths than fires,
drownings and airplane crashes combined." People
spend most of their time at home - on average 70%, more
for children. The cumulative exposure to ionizing radiation
from radon and the lung cancer risks to a person are dependent
on the radon level in his/her home:
Radon Level
(pCi/L) |
Population
Mortality |
Risk Comparison |
20 |
11.8% |
90 |
times the
risk of dying by |
drowning |
80 |
" |
home fire |
6 |
" |
violent crime |
3 |
" |
car crash |
40 |
" |
airplane crash |
|
10 |
5.9% |
8 |
4.7% |
4 |
2.4% |
2 |
1.2% |
(Source: EPA Citizen's Guide to Radon,
NAS BEIR VI Report)
The death risk to the average person from radon gas at
home is 1,000 higher than the risk from any other carcinogen
or toxin regulated by FDA or EPA. Safety limits are expressed
in deaths per 100,000 people, but radon risks in percentages
(1 per 100 people).
The health risks are proportional to radon level
The passage of a single alpha particle can cause mutations
of DNA in your lungs, and some cells may become cancerous.
Most cancers originate from damage to a single cell. The
more radiation particles that pass through the human body,
the higher the chances of developing lung cancer. Therefore,
the risk to people is proportional to the length of exposure
and the radon concentration in air.
The radon risk drops off for high concentrations, like
for miners, because more lung cells are killed off by
the radiation rather than becoming cancerous, and some
radiation is wasted on the already killed cells (the "inverse
exposure-rate effect"). But at lower concentrations,
like at home, every emitted particle counts.
Radioactivity is dangerous at any level and even the
low levels of radon gas outdoors (average level 0.4 pci/L)
are not harmless.
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