[ RadSafe ] protraction enhancement effect

[Otto G. Raabe]

At 03:54 PM 9/1/2010, Jerry Cohen wrote:
>If this protracted dose hypothesis were valid, then people in 
>Colorado would be worse off those in California. Cancer mortality 
>statistics show the opposite effect. As I recall from the Radiation 
>Biology class I had about 50 years ago, in the low-dose range (<5.0 
>rem), the dose rate is unimportant.
>Have things changed since then?
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Dear Jerry,

As described in my March HPJ paper, at low dose rates the latency is 
so long that it exceeds the natural life span resulting in a life 
span virtual threshold at cumulative doses less than 20 Sv  (2000 
rem) to the target tissues  (bronchial epithelium in the case of 
radon decay products).

So, even though the radiation is "more effective"  in observed cases 
at lower life time average dose rates, radiation-induced lung cancer 
cases are rare for cumulative doses less than 20 Sv.

Otto


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Prof. Otto G. Raabe, Ph.D., CHP
Center for Health & the Environment
University of California
One Shields Avenue
Davis, CA 95616
E-Mail: ograabe at ucdavis.edu
Phone: (530) 752-7754   FAX: (530) 758-6140
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