Some reasons not to believe the linear no-threshold hypothesis

["Dukelow, James S Jr" <jim.dukelow@pnl.gov>]

I sent the following to RISKANAL, a mailing list for risk professionals, in the
context of a general discussion of the LNTH.

It seems relevant to the current discussion on RADSAFE, also.
-----Original Message-----
From:	Dukelow, James S Jr 
Sent:	Thursday, March 16, 2000 3:10 PM
To:	'riskanal@lyris.pnl.gov'
Subject:	A partial response to Finkel and Dankovic

Some reasons not to believe the linear no-threshold hypothesis.

First, and most flip, it has a lot of the flavor of homeopathy.

Second, it is so implausible as to strain credulity.  Living cells and 
living organisms have a variety of essentially independent schemes for 
preventing cancer.  Human cells have several different DNA-repair 
mechanisms.  If these fail to repair damaged DNA, there are mechanisms 
for identifying the failure and commanding cell suicide.  If this fails, 
immune system surveillance and response may destroy the proto-tumor.  A 
small solid tumor cannot grow past a certain point without inducing the 
body to build it a network of blood vessels to provide nourishment and 
remove wastes.  A solid tumor may need to metastasize before it can 
finally kill its host.  All of these lines of defense work with a 
greater or lesser degree of effectiveness, but with sufficient 
effectiveness that a majority of humans live long enough to die of 
something else.