Re: Number of chromosome repairs

[Andrew Karam <karam.1@osu.edu>]

>Dear Radsafers:
>
>A staff member has asked the following question:
>
>What is the average number of chromosome repairs per day?
>
>I guess around 100K, but would appreciate something a bit
>more scientifically concrete.
>

According to Billen (Spontaneous DNA Damage and Its Significance for the
"Negligible Dose" Controversy in Radiation Protection, Radiation Research,
124 pp 242-245, 1990) there are about 10,000 measureable DNA modification
event per hour in each mammalian cell due to intrinsic causes (roughly
quoted).  He goes into more detail as to the source of these, but he
equates this to the damage done by about 80 cGy per hour.

Hope this helps.

Andy

The opinions expressed above are well-reasoned and insightful.  Needless to
say, they are not those of my employer. (with apologies to Michael Feldman)		

Andrew Karam, CHP  (karam.1@osu.edu)		(614) 292-1284 (phone)
The Ohio State University 				(614) 292-7002 (fax)
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