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Re: Fallout blamed for thyroid cancer -Reply -Reply -Reply -Reply
Charlie, Michael and others,
>While 1 Gy may lead to 20 DNA alterations per exposed cell in the
>human body, those same cells with go through 90 million DNA
>alterations in one year through normal metabolism.
I think there are important qualitive differences here: 1 Gy to
a human diploid cell typically gives about 35-40 DNA double-strand
breaks (DSBs) and perhaps as many as 25 to 50 times more of
single-strand breaks (SSBs). Whereas about 1 in 40 DSBs is lethal to the
cell, it may be normal for the same cell to have as many as 3000 SSBs
at the same time - and a metabolic change may make that number
increase by up to perhaps 100,000 SSBs. LD50 for cells may occur at
about 2 million simultaneous SSBs per cell. There are also many other
relatively trivial types of DNA damage like base losses etc. A gene
in a single cell may take billions of such damages throught a person's
lifetime.
Thyroid cancer in the U.S. - the 40% increase: 1. Is there any
specific group? 2. Is there any clear info. about the age structure
of these individuals?
I am in particular thinking about the people who came from former
Soviet Union. In Brooklyn alone - I think there are about 100,000
individuals from Russia, Ukraine, Belarus etc who arrived after
glasnost and perestroyka.
bjorn_cedervall@hotmail.com
Depts. Medical Radiation Biology & Medical Radiation Physics,
Karolinska Institutet, Box 260, S-171 76 Stockholm, Sweden
Ph/fax: Int + 468 343525 (Med. Radiation Physics)
Website: http://www.geocities.com/WallStreet/Exchange/8256/
Any opinions expressed above are those of mine and may not necessarily
coincide with those of others.
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