Re: Linear-no threshold question

[Free Spirit <FRANK@rover.bsd.uchicago.edu>]

>Message-Id: <9601101711.AA52453@admin-one.radbio.mcw.edu>
>From: "John Moulder" <jmoulder@post.its.mcw.edu>

>The questions of more general interest are whether the linear no-threshold 
>model is a reasonable model for continuous low dose exposure (public 
>exposure); to low dose fractionated exposure at high dose rates (most 
>occupational radiation protection); or to single fraction high dose rate 
>exposures (most medical diagnostic exposure).

	Nobody ('cept John) wants to admit that fractionation is a
	significant factor. Why? Because it turns a complicated problem
	into one worthy of a Solomon.

>BTW:  For the general case of protracted exposure to low-LET radiation, it is 
>relatively easy to show that linear no threshold model, as applied in BEIR V, 
>predicts that no statistically significant effects will be seen in human 
>populations below a total dose of around 1000 mSv.  

	Hmm. John. Is this true also for the relatively rare cancers? From my
	recollection, no statistically significance was seen in the Hiroshima/
	Nagasaki survivors, even up near leathal doses. If its also true for
	low doses, dang we're wasting LOTS of money.

Frank R. Borger - Physicist     ___      "One third of the rats were improved
Michael Reese - U of Chicago   |___      on the experimental medication, one
Center for Radiation Therapy   | |_) _   third remained the same, and the 
net: Frank@rover.uchicago.edu    | \|_)  other one third could not be repor-
ph: 312-791-8075 fa: 791-2517       |_)  ted on, because that rat got away."
                                         - Edwin Bidwell Wilson