Saturday, April 5, 2008

Problem with radon?

Now one has to wonder about this issue of significant human fatalities attributed to radon as compared to other carcinogenic villains. The Environmental Protection Agency claims there are 20,000 deaths each year due to radon exposure--a broader range of 7,000 to 33,000. How is this known? How is it determined that radon is the ultimate cause of those deaths?

Beyond the obvious tragedies of the lethal effects of radium decay, this question is relevant in that it exemplifies the care in obtaining accurate information regarding statistics such as those quoted. I am always guarded when I see a broad display of statistics especially when it is coming from a government agency. One needs to probe a bit deeper and analyze the data. Thus, I headed for various web sites to discover, right away, the wide range of the death statistics: 7,000 to 33,000 annually. Okay, such a disparity for me is suspect in the process of data gathering, data analysis, and cautionary extrapolation.

Reflecting a bit more about this issue one has to wonder what all the fuss was about: Was it motivated by the sales of "radon detection kits" [big bucks] or was it the latest of a heath related issue? We are still being warned about the dangers of excessive ultraviolet radiation i.e., carcinogenic melanoma. Now there's a billion dollar industry of sun blocking creams and ointments. Mercury contaminated fish, smoke stack emissions from industry and power plants, the usual toxic spills, the fibrous asbestos, and on and on. Radon gas poisoning may be just a part of a string of revenue generating schemes or part of a list of human perils.

The point is one has to be careful when making statistical statements and extrapolating a conclusion.

Further reading...

"An Introduction To Radiation Hormesis"

"Beware Of EPA's Flawed Radon-Cancer Connection"

"EPA Refuses To Face The Facts On Radon Risks"


Just in case you are interested in the nuclear chemistry decay of radon:

1.) Start with a uranium-238 atom. This atom has 92 protons and 146 neutrons. It has a half-life of 4.5 billion years. When it decays it emits an alpha particle, leaving behind a thorium-234 atom.

2.) A thorium-234 atom has 90 protons and 144 neutrons. It has a half-life of 24.5 days. When it decays it emits a beta particle and a gamma ray, leaving behind a protactinium-234 atom.

3.) A protactinium-234 atom has 91 protons and 143 neutrons. It has a half-life of 269,000 years. When it decays it emits a beta particle and a gamma ray, leaving behind a thorium-230 atom.

4.) A thorium-230 atom has 90 protons and 140 neutrons. It has a half-life of 83,000 years. When it decays it emits an alpha particle and a gamma ray, leaving behind a radium-226 atom.

5.) A radium-226 atom has 88 protons and 138 neutrons. It has a half-life of 1,590 years. When it decays it emits an alpha particle and a gamma ray, leaving behind a radon-222 atom.

6.) radon-222, with a half-life of 3.825 days, emits an alpha particle to become polonium-218.

7.) polonium-218, with a half-life of 3.05 minutes, emits an alpha particle to become lead-214.

8.) lead-214, with a half-life of 26.8 minutes, emits a beta particle and a gamma ray to become bismuth-214.

9.) bismuth-214, with a half-life of 19.7 minutes, emits either an alpha particle or a beta particle and a gamma ray to become either thallium-210 or polonium-214.

10.) polonium-214, with a half-life of a 150 microseconds, emits an alpha particle to become thallium-210.

11.) thallium-210, with a half-life of 1.32 minutes, emits a beta particle to become lead-210.

12.) lead-210, with a half-life of 22 years, emits a beta particle and a gamma ray to become bismuth-210.

13.) bismuth-210, with a half-life of five days, emits a beta particle to become polonium-210.

14.) polonium-210, with a half-life of 138 days, emits an alpha particle and a gamma ray to become lead-206.

15.) lead-206 is a stable isotope of lead.


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