CR3 News Magazine 2020 VOL 3: MAY Medical - Radon vs Covid-19 | Page 11

drinking water from groundwater that contains
radon. Radon gas escapes from the water and
goes into the air when water that contains
radon is used in the home for showering,
washing dishes, and cooking. Radon in domestic
water generally contributes only a small
proportion (about 1 to 2 percent) of the total
radon in indoor air. Radon levels in air and
groundwater will generally be higher in areas of
the country with rock types that contain high
amounts of uranium and radium, such as
phosphate or granite.
How can radon affect people’s health?
Exposure to radon and its daughters increases
the chance that a person will develop lung
cancer. The increased risk of lung cancer from
radon primarily results from alpha particles
irradiating lung tissues. Most of the damage is
not from radon gas itself, which is removed from
the lungs by exhalation, but from radon’s short-
lived decay products (half-life measured in
minutes or less). When inhaled, these decay
products may be deposited in the airways of the
lungs, especially if attached to dust particles,
and subsequently emit alpha particles as they
decay further, resulting in damage to cells lining
the airways.
How does radon get into the body?
Radon and its radioactive daughters can enter
the body through inhalation and ingestion.
Inhaling radon is the main route of entry into
the body, with most of the radon being exhaled
again. However, some radon and its daughter
products will remain in the lungs, where
radiation released during the decay process
passes into the lung tissues, causing damage.
Radon is also produced in the body from parent
radium deposited in the body.
Radon is considered a known human carcinogen
based on extensive studies of exposure to
human beings. In two 1999 reports, the National
Academy of Sciences (NAS) concluded that
radon in indoor air is the second leading cause
of lung cancer in the U.S. after cigarette
smoking. The NAS estimated that the annual
number of radon-related lung cancer deaths in
the U.S., is about 15,000 to 22,000. NAS also
estimated that radon in drinking water causes
about 180 cancer deaths each year in the United
States. Approximately 89 percent of these
cancer deaths are caused by lung cancer from
inhalation of radon released to indoor air from
the water, and about 11 percent are a result of
cancers of internal organs, mostly stomach
cancers, from ingestion of radon in water.
Is there a medical test to determine
exposure to radon?
Radon in human tissue is not detectable by
routine medical testing. However, several of its
decay products can be detected in urine, in lung
and bone tissue, and by breath tests. These
tests, however, are not generally available to the
public. They are also of limited value since they
cannot be used to determine accurately how
much radon a person was exposed to, nor can
these tests be used to predict whether a person
will develop harmful health effects.
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