Re: Fwd: John Cameron & radiation risks (is there ANY evidence

[Tom Mohaupt <tmohaupt@wright.edu>]

Walter Huda attributes John Cameron as saying that there is no data 
for radiocarcinogenisis at doses below  25 rads.  Dr. Huda has 
challenged Dr. Cameron on this statement using a thyroid cancer study 
of Israeli children treated for tinea capitis infections.  The 
reference given by Dr. Huda [Radiation Carcinogenisis, edited by A. 
Upton, published by Elsevier, 1996, page 294] actually presents two tinea 
capitis studies - one in New York by Albert and Omram and the other 
in Israel by Modan. The Israel study is also addressed in NCRP 80 
(page 15).  The estmated mean thyroid dose was 9 rads, range 4.3 - 
16.9 rads.  Interestingly, where the Israeli study showed a relative 
risk of 5.4 (29 cancers in 10,842 persons treated), the New York 
study was negative.  Reflecting on the difference, the authors of the 
chapter in Radiation Carcinogenisis note that the Israeli study did 
not use any tinea capitis patients as controls, where the New York 
study used tinea capitis patients who were treated by topical 
medications only as the controls.  

Epidemiology is a blunt tool that requires consistent findings to 
correlate a suspected cause and effect.  Perhaps, Dr. Cameron's 
answer was already there for you.

Tom Mohaupt, M.S., CHP