[ RadSafe ] ERR query: the exact form of LNT

[Strom, Daniel J]

This equation is valid for common or rare background cancers. Its high
dose behavior asymptotically approaches a probability of 1 at very high
doses. For acute whole-body irradiation, that is, of course, nonsense,
since everyone would die of one or another acute radiation syndrome.
However, for protracted partial body irradiation, such as the bone
surfaces of radium dial painters, it's sensible. 
 
In a more complete version of the equation that includes a threshold, P
also includes background cancer (incidence or mortality or whatever the
risk is):
 
P(n' > 0 | b, k, D, D_0) = 1 - EXP(-{k[D - D_0] + b})
 
where 
n' is the total number of tumors in an individual, both radiogenic and
nonradiogenic
b is the background incidence; the probability of an individual
contracting this kind of cancer in the absence of radiation exposure is
= EXP(-b)
k  is the probability per unit dose
D is the dose
D_0 is a threshold dose
 
- Dan Strom 

The opinions expressed above, if any, are mine alone and have not been
reviewed or approved by Battelle, the Pacific Northwest National
Laboratory, or the U.S. Department of Energy.

Daniel J. Strom, Ph.D., CHP 
Energy and Environment Directorate, Pacific Northwest National
Laboratory 
Mail Stop K3-56, PO BOX 999, Richland, Washington 99352-0999 USA 
Overnight: Battelle for the U.S. DOE, 790 6th St., Richland WA 99354
ATTN: Dan Strom K3-56 
Telephone (509) 375-2626 FAX (509) 375-2019 mailto:strom at pnl.gov 
Radiological Sciences and Engineering:
http://radiologicalsciences.pnl.gov/ 
Brief Resume: http://www.pnl.gov/bayesian/strom/strombio.htm 
Online Publications: http://www.pnl.gov/bayesian/strom/strompub.htm 
Pagemaster for  http://www.pnl.gov/bayesian   http://qecc.pnl.gov
<http://qecc.pnl.gov/>    http://bidug.pnl.gov <http://bidug.pnl.gov/>  

 


________________________________

From: garyi at trinityphysics.com [mailto:garyi at trinityphysics.com] 
Sent: Monday, January 14, 2008 12:46 PM
To: radsafe at radlab.nl; Strom, Daniel J
Cc: Strom, Daniel J
Subject: Re: [ RadSafe ] ERR query: the exact form of LNT


So you are saying that the kD approximation is only good for a given
cancer type if the background probability is low - is that it? 


-Gary Isenhower