Re: Laymans questions on hormesis and LNT

[BERNARD L COHEN <blc+@PITT.EDU>]

On Thu, 28 Aug 2003, Dimiter Popoff wrote:



> Since I have been on this list I have read words like 'hormesis' and LNT

> innumerable times and eventually - although I have no medical knowledge - I

> have some questions.



	--I see no conflict between hormesis and LNT. LNT applies to

cancer initiating DNA damage, and seems logical from that standpoint.

However it must be recognized that this is added to a very large

background of such DNA damage events occurring naturally, trillions of

times per day in each person. If this were the only important thing, we

would all die of cancer at a very young age.

Hormesis arises from stimulation of repair enzyme production, stimulation

of immune response, stimultion of apoptosis, modification of cell cycle

timing, etc. There is no reason to believe that these vary linearly with

dose, and there is direct evidence to the contrary, indicating that

hormesis apples most to low level radiation.

	The only question is what happens when you add the two effects.

There is strong evidence indicating that hormesis predominates for low

level radiation. Where is the contrary evidence?

************************************************************************

You are currently subscribed to the Radsafe mailing list. To unsubscribe,

send an e-mail to Majordomo@list.vanderbilt.edu  Put the text "unsubscribe

radsafe" (no quote marks) in the body of the e-mail, with no subject line.

You can view the Radsafe archives at http://www.vanderbilt.edu/radsafe/