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What is radon? Radon is a cancer-causing radioactive gas. You cannot see, smell
or taste radon but it may be a problem in your home. When you breathe air containing
radon, you increase your risk of getting lung cancer. In fact, the Surgeon General
has warned that radon is the second leading cause of lung cancer in the United
States today. If you smoke and your home has high radon levels, your risk of lung
cancer is especially high. Radon (A more scientific description) A gaseous highly
radioactive element. Discovered by English physicist Ernest Rutherford in 1899.
Although the discovery is *also* credited to German physicist Friedrich Ernst
Dorn in 1900, it may be fairer to say that Rutherford discovered radon's alpha
radiation and that Dorn found that radium was giving off a gas. (We welcome input
from anyone with additional documentation concerning this issue.) E-mail to: Radon's
Discoverer? Radon is a colorless, chemically unreactive inert gas, it is the densest
gas known. The gas and its highly radioactive (radioactivity described) metallic
daughter products emit alpha and beta particles and gamma rays. It has been used
in the treatment of cancer by radiotherapy. In homes and other buildings, in some
areas of the world, radon produced by the radioactive decay of uranium-238 present
in soil and rock can reach levels regarded as dangerous. (Chemical Symbol/Element
Number: Rn222) (Page Down for additional scientific info.) Should you test for
radon? Testing is the only way to know your home’s radon levels. There are
no immediate symptoms that will alert you to the presence of radon. It typically
takes years of exposure before any problems surface and then it is too late. The
U.S. Environmental Protection Agency, Surgeon General, American Lung Association,
American Medical Association and National Safety Council all recommend testing
your home for radon. Can you fix the problem? If you find that your home has high
radon levels, there are ways to reduce the concentrations. Even very high levels
can be reduced to acceptable levels. Most radon problems can be fixed by a do-it-yourselfer
for for less than $500. If you need the assistance of a professional click on
*Radon FAQ* (at the left) for some answers and links to other useful sites. RADIATION
AND RISK FACTS The alpha radiation emitted by radon is the exact same alpha radiation
that is emitted by any other alpha generating radiation source, like plutonium.
A family whose home has radon levels of 4 pCi/l is exposed to approximately 35
times as much radiation as the NUCLEAR REGULATORY COMMISSION allows if they were
standing next to the fence of a radioactive waste site. (25 mrem limit, 800 mrem
exposure) An elementary school student that spends 8 hours per day and 180 days
per year in a classroom with 4 pCi/l of radon will receive nearly 10 times as
much radiation as the NUCLEAR REGULATORY COMMISSION allows at the edge of a nuclear
power plant.(25 mrem limit, 200 mrem exposure) Most United States Environmental
Protection Agency (EPA) lifetime safety standards for carcinogens are established
based on a 1 in 100,000 risk of death. Most scientists agree that the risk of
death for radon at 4 pCi/l is approximately 1 in 100. At the 4 pCi/l EPA action
guideline level radon carries approximately 1000 times the risk of death as any
other EPA carcinogen. Radon induced lung cancer costs the United States over $2
Billion dollars per year in both direct and indirect health care costs. (Based
on National Cancer Institute statistics of 14,400 annual radon lung cancer deaths)
Radon's primary hazard is caused from inhalation of the gas and its highly radioactive
heavy metallic decay products (Polonium, Lead, and Bismuth) which tend to collect
on dust in the air. The problem arises when these elements stick to the delicate
cells lining the passageways leading into the lungs. There is sufficient evidence
for the carcinogenicity of radon and its isotopic forms, radon-222 and radon-220,
in experimental animals. When administered by inhalation, preceded by a single
exposure to cerium hydroxide dust, radon induced pulmonary adenomas, adenocarcinomas,
invasive mixed adenosquamous carcinomas, and squamous cell carcinomas in male
rats. Extrapulmonary metastases occurred in only one animal. Most or all of the
tumors were believed to be bronchiolar or bronchio-alveolar in origin. Radon decay
products in combination with uranium-ore dust induced a progression of activity
from single basal cell hyperplasia in bronchioles to malignant tumors in male
hamsters when exposed by inhalation. Lung tumors observed were adenomas, adenocarcinomas,
and squamous cell carcinomas; bronchiolar and alveolar metaplasia, adenomatous
lesions, fibrosis, and interstitial pneumonia were also observed. When administered
by inhalation in combination with decay products, uranium-ore dust, and cigarette
smoke, radon-induced nasal carcinomas, epidermoid carcinomas, bronchio-alveolar
carcinomas, and fibrosarcoma were observed in dogs of both sexes. In general,
a significant increase was observed in respiratory tract tumors in rats and dogs
in comparison with unexposed animals. A dose- response relationship was noted
in those experiments with rats in which radon was tested. In most instances, tumors
at sites other than the lung were not reported, but in one study, mention was
made of tumors of the upper lip and urinary tract in rats. An IARC Working Group
reported that there is sufficient evidence for the carcinogenicity of radon and
its decay products in humans. Increased incidences of lung cancer have been reported
from numerous epidemiologic studies of groups occupationally exposed to high doses
of radon, especially underground hard rock miners. These include particularly
uranium miners, but also groups of iron-ore and other metal miners, and one group
of fluorspar miners. Strong evidence for exposure response relationships has been
obtained from several studies, in spite of uncertainties that affect estimates
of the exposure of the study populations to radon decay products. Several small
case-control studies of lung cancer have suggested a higher risk among individuals
living in houses known or presumed to have higher levels of radon and its decay
products than among individuals with lower presumed exposure in houses. The evidence
on the interaction of radon and its decay products with cigarette smoking with
regard to lung cancer does not lead to a simple conclusion. The data from the
largest study are consistent with a multiplicative or submultiplicative model
of synergisms and reject an additive model. In many studies of miners and in one
of presumed domestic exposure, small cell cancers accounted for a greater proportion
than expected of the lung cancer cases. In one population of uranium miners, this
proportion has been declining with the passage of time. Because of the limited
scale of epidemiologic studies of nonoccupational exposure to radon decay products
available at the time reviews were made, quantification of risk has been based
only on data of miners' experience. An IARC Working Group considered that the
epidemiologic evidence does not lead to a firm conclusion concerning the interaction
between exposure to radon decay products and tobacco smoking. Most of the epidemiologic
studies involve small numbers of cases, and the analytical approaches for assessing
interaction have been variable and sometimes inadequate. PROPERTIES Radon was
discovered in 1900 by Friedrich Ernst Dorn, (Germany). Named after the element
"radium" (radon was called niton at first, from the Latin word "nitens"
meaning "shining") but has been called radon since 1923. It is an essentially
inert, colorless, odorless gas at ordinary temperatures. Its melting point is
202 degrees K and the boiling point is 211 degrees K. When cooled below the freezing
point radon exhibits a brilliant phosphorescence which becomes yellow as the temperature
is lowered and orange-red at the temperature of liquid air. The atomic radius
is 1.34 angstroms and it is the heaviest known gas, being nine times denser than
air. Because it is a single atom gas (unlike oxygen, O2, which is comprised of
two atoms) it easily penetrates many common materials like paper, leather, low
density plastic (like plastic bags, etc.) most paints, and building materials
like gypsum board (sheetrock), concrete block, mortar, sheathing paper (tarpaper),
wood paneling, and most insulation. Radon is also fairly soluble in water and
organic solvents. Although reaction with other compounds is comparatively rare,
it is not completely inert and forms stable molecules with highly electronegative
materials. Radon is considered a noble gas that occurs in several isotopic forms.
Only two are found in significant concentrations in the human environment: radon-222,
and radon-220. Radon-222 is a member of the radioactive decay chain of uranium-238,
and radon-220 is formed in the decay chain of thorium-232. Radon-222 decays in
a sequence of radionuclides called radon decay products, radon daughters, or radon
progeny. It is radon-222 that most readily occurs in the environment. Atmospheric
releases of radon-222 results in the formation of decay products that are radioisotopes
of heavy metals (polonium, lead, bismuth) and rapidly attach to other airborne
materials such as dust and other materials facilitating inhalation. USE Radon
is a noble gas. Only two of its isotopic forms are found in significant concentrations
in the human environment: radon-222 and radon-220. Their decay products are not
gases and occur as unattached ions or atoms, condensation nuceli, or attached
to particles. This decay product of uranium-238 is commonly found in uranium mines.
Radon has been used in some spas for presumed medical effects. In addition, radon
is used to initiate and influence chemical reactions and as a surface label in
the study of surface reactions. It has been obtained by pumping the gases off
of a solution of a radium salt, sparking the gas mixture to combine the hydrogen
and oxygen, removing the water and carbon dioxide by adsorption, and freezing
out the radon. PRODUCTION Radon is not produced as a commercial product. Radon
is a naturally occurring radioactive gas and comes from the natural breakdown
(radioactive decay) of uranium. Most soils contain varying amounts of uranium.
It is usually found in igneous rock and soil, but in some cases, well water may
also be a source of radon. EXPOSURE The primary routes of potential human exposure
to radon are inhalation and ingestion. Radon in the ground, groundwater, or building
materials enters working and living spaces and disintegrates into its decay products.
In comparison with levels in outdoor air, the concentrations of radon and its
decay products to which humans are exposed in confined air spaces, particularly
in underground work areas such as mines and buildings, are elevated. Although
high concentrations of radon in groundwater may contribute to human exposure through
ingestion, the radiation dose to the body due to inhalation of radon released
from water is usually more important. Concentrations of radon decay products measured
in the air of underground mines throughout the world vary by several orders of
magnitude. In countries for which data were available, concentrations of radon
decay products in underground mines are now typically less than 1000 Bq/m3 EEC
Rn (approx. 28 pCi/l). The average radon concentrations in houses are generally
much lower than the average radon concentrations in underground ore mines. Workers
are exposed to radon in several occupations. Underground uranium miners are exposed
to the highest levels of radon and its decay products. Other underground workers
and certain mineral processing workers may also be exposed to significant levels.
Exhalation of radon from ordinary rock and soils and from radon- rich water can
cause significant radon concentrations in tunnels, power stations, caves, public
baths, and spas. Peripheral lymphocyte chromosomes from 80 underground uranium
miners and 20 male controls in the Colorado plateau were studied. Taken into account
were confounding factors such as cigarette smoking and diagnostic radiation. Groups
that were increasingly exposed to radon and its decay products were selected.
Significantly more chromosomal aberrations were observed among miners with atypical
bronchial cell cytology, suspected carcinoma, or carcinoma in situ than among
miners with regular or mildly atypical cells, as evaluated by sputum cell cytology.
The Environmental Protection Agency (U.S. E.P.A.) and the Surgeons General's Office
have urged widespread testing for radon. They estimated that as many as 20,000
lung cancer deaths are caused each year by radon. Next to smoking, radon is the
second leading cause of lung cancer. EPA says that nearly 1 in 3 homes checked
in seven states and on three Indian lands had screening levels over 4 pCi/L, the
EPA's recommended action level for radon exposure. Radon is a national environmental
health problem. Elevated radon levels have been discovered in virtually every
state. The EPA estimates that as many as 8 million homes throughout the country
have elevated levels of radon. State surveys to date show that 1 out of 5 homes
has elevated radon levels. Radon seeps into homes from the surrounding soil through
cracks and other openings in the foundation. Indoor radon has been judged to be
the most serious environmental carcinogen to which the general public is exposed
and which the EPA must address. Based on current exposure and risk estimates,
radon exposure in single-family houses may be a causal factor in as many as 20,000
of the total lung cancer fatalities which occur each year. Radon decay products
(polonium- 218 and polonium-214, solid form) can attach to the surface of aerosols,
dusts, and smoke particles which may be inhaled, and become deeply lodged or trapped
in the lungs. Once lodged, they can radiate and penetrate the cells of mucous
membranes, bronchi, and other pulmonary tissues. Some scientific studies of radon
exposure indicate that children may be more sensitive to radon. This may be due
to their higher respiration rate and their rapidly dividing cells, which may be
more vulnerable to radiation damage. Radioactivity --- a Summary: The spontaneous
disintegration or decay of the nucleus of an atom by emission of particles, usually
accompanied by electromagnetic radiation. Natural radioactivity is exhibited by
several elements, including uranium, radium, radon gas, and radon's daughters.
The radiation produced is of three types: the alpha particle with relatively weak
penetration power, which is a nucleus (two protons and two neutrons) of an ordinary
helium atom; the beta particle with moderate penetration power, which is a high-speed
electron or, in some cases, a positron (the electron's antiparticle); and gamma
radiation, which is a type of electromagnetic radiation with very short wavelengths
resulting in very high penetration power. The rate of disintegration of a radioactive
substance is commonly designated by its half-life, which is the time required
for one half of a given quantity of the substance to decay. For example, if you
had a two liter bottle (think of the large soda bottle in the fridge) that was
filled with radon gas and then tighly sealed, at the end of one half-life (approximately
92 hours or almost 4 days) there would only be one liter left in the bottle. Another
issue to consider is the *unusual* property of the radioactive decay chain of
uranium/radium/radon. What makes this seem unusual is that a gas is produced from
a radioactive solid element (a rock) and then the radioactive gas changes back
into radioactive heavy metallic particles. This process and their atomic size
(extremely small) makes possible the transport of radioactive atoms through a
relatively static environment. In other words, radon's extended half-life (it
takes about a month for a specific amount of it to decay to almost nothing) provides
enough time for the gas to migrate through cracks and crevices in building foundations,
then into the internal air volume where it changes into the more harmful radioactive
heavy metals. This gas and the resulting very small metallic particles (so small
that they will float in air) move quickly through a building or home, contaminating
the air. An analogy that makes this easier to understand is to think how easily
some can detect the presence of a smoker in another part of the building or the
cooking of coffee or bacon in the kitchen on Sunday morning. In other words, almost
nothing will stop this gas from moving from the basement to other parts of a house
if it makes its way into the basement in the first place. Be sure you visit our
Radon FAQ page for answers on how to stop this gas before it enters your home.

From: Rachel's #100, October 24, 1988

Date: 04 Jun 1999


Rachel's #100, October 24, 1988

Despite What You May Suspect, The Danger From Radon Is Real The federal EPA
(U.S. Environmental Protection Agency) announced in midSeptember that 1/3 of
all U.S. homes may contain dangerous levels of radon, a colorless, odorless,
tasteless cancer-causing gas created by nature. The agency said as many as 20,000
Americans may be dying each year from lung cancer caused by radon in homes.
They said all homes should be tested for the presence of radon. Coming 60 days
before the election, the announcement looked political. But we believe our readers
should take this threat seriously. Here's why:

There can be absolutely no doubt that radon causes lung cancer in humans. An
epidemic of lung cancer is now sweeping through the men who worked the uranium
mines in our Western states from 1940 to today. European miners show similar
cancers from similar exposures. Radon gas is not something you want to breathe
and it is not something you want your children to breathe.

Radon is a natural hazard, but this does not make it safe by any means. Radon
is formed by the naturally-occurring radioactive decay of uranium, an element
that occurs in all soil (more in some soils, less in others). Radon is heavier
than air, so it tends to collect in low places that are poorly-ventilated, such
as basements. Newer homes may be especially prone to a buildup of radon because
they are often designed with poor ventilation as an energy-conservation measure.

The EPA has probably not overestimated the danger from exposure to particular
levels of radon. What the agency may have overestimated is the amount of radon
in peoples' homes. The agency's tests generally occur during the winter, when
people keep their houses zipped up against the cold. Therefore the agency's
tests may have overestimated the average exposures that people endure because
the average must take into account both winter and summer conditions.

Nevertheless, the radon problem is something we should each evaluate in our
own homes, including apartments below the 3rd floor. You can get a quick (one-day
to one-week) sample of the air in your home tested for radon for about $10.00,
but a sample of the air taken over a longer period (90 days to a year) is much
more reliable for showing you the average amount of radon in your home, which
is what you care about. One high reading for a day or a week is cause for concern
(it should prompt you to do a longer test) but it is not cause for panic. On
the other hand, a low reading for one day or one week does not prove there's
no danger. It is the long-term average that will create the cancer risk, so
that is what you want to know about.

The Reagan Administration (and certain state governments, such as New Jersey's)
would have you believe that the radon problem is so serious that you should
forget about the toxic chemicals in your air and water. This is dangerously
false. At a minimum, the hazard from radon in your home will be added to the
danger you face from chemicals. Worse yet, there is abundant evidence from cigarette-smoking
uranium miners that the effects of radon and some chemicals may be multiplied,
creating a combined hazard much worse than the two hazards added together. This
is called synergism and there is a definite synergistic effect between the chemicals
in tobacco smoke and radon gas. Therefore, the radon danger should make us redouble
our efforts to rid the environment of toxic chemicals; nature provided the earth
with a background level of hazards [radon, cosmic rays, black widow spiders,
to name a few], so we should work hard to prevent greedy humans from adding
industrial hazards and making the situation worse.

Therefore, though we believe Mr. Reagan hoped the radon announcement would
take your mind off the toxic chemicals that his EPA has failed to control over
the last eight years, we believe radon should be taken very seriously by people
who care about their health. The radon threat should be evaluated house by house.
This problem has been known in New Jersey and Pennsylvania since 1984 and we
have studied it closely. We firmly believe the danger is real.

We think the New York Times gave good advice when they suggested that their
readers contact a company called Air-Chek, Box 2000, Arden, NC 28704; phone
(704) 684-0893. Air-Check will sell you one short term [charcoal canister] test
for $9.95, or 3 short tests for $24.95. [Check the basement and typical living
areas, such as living room and a bedroom.] They sell 3 of the longerterm, more
reliable [called alpha track] tests for $49.95 and this is the test we recommend.
These tests are simple. They mail you a canister about the size of a can of
shoe polish. You set it in your home for the recommended time period, then mail
it back. They analyze it and send you the results along with an explanation.

The EPA says 4 picoCuries of radon per liter of air is "safe," but
they also admit that this is four times the natural background level, and that
4 picoCuries is the equivalent of getting 200 to 300 chest x-rays per year or
smoking 1/2 a pack of cigarettes per day. They say 1% to 5% of the people exposed
to such a level 75% of the time for 70 years will develop lung cancer. We believe
the federal standard should be cut in half; in truth, we favor reducing the
level inside homes to background (one picoCurie per liter). And of course no
one should use tobacco at all. We favor a law requiring alpha track testing
for any house that's sold.

Ventilating a home with fresh air is the right antidote to the radon hazard.
If you find excessive radon in your home, it can be fixed easily for an average
cost of $500 to $1000. Don't panic, don't move out, and don't be afraid to buy
a house. But above all, don't ignore the problem just because it was Mr. Reagan's
EPA who brought it to light.

To learn more about the problem in your area and to find reliable people who
can advise you on testing and mitigation, contact the American Association of
Radon Scientists and Technicians, a trade group: P.O. Box 70, Park Ridge, NJ
07656; phone (201) 391-6445.

Recently, Bernard Cohen, a pro-nuke scientist at University of Pittsburgh,
has been saying he has evidence that a little radon (between 1 and 4 picoCuries
per liter) may actually be good for you. [For example, see SCIENCE NEWS Vol.
134 (Oct. 15, 1988), pg. 254.] This is an interesting theory, but it's definitely
not something you want to bet your health or your children's health on. Be safe;
test for radon, then mitigate.

--Peter Montague



Some people are talking about it and some people are DOING it. There's a huge
group in Louisiana that's DOING it. Five organizations are sponsoring a 9-day,
70-mile march from Baton Rouge to New Orleans, Nov. 11 to 20 through Louisiana's
"cancer alley." Along the way they've planned actions that will highlight
the problems and will bring folks together. Try to be there! More on this next

For information, contact Darryl Malke-Wiley, The Sierra Club, 3227 Canal St.,
New Orleans, LA 70119; phone (504) 822-8760.

  [Posted by radon.com on 12/2/2004] Reply to this message