Re: x-rays, IRB, rad-safty, consents, r -Reply

[FRAMEP@ORAU.GOV]

Bonjour mes amis

Jim Muckerheide wrote in part:

>Of course this begs the question of whether 1 rad to 1 gram, and 1
>rad to the whole brain, are equivalent when dealing with dose risks,
>and the matter of the need to look at  radiation differently than
>other toxins. 

Jim:

Radiation is not  a toxin. Mutagenic agent is another story.

I don't recall anyone ever remotely suggesting that 1 rad to one gram
carried an equivalent risk to one rad to the whole brain or any other
similar tissue. That argument looks suspiciously like a strawman 
created for the purpose of being knocked down. 

Rads are units of absorbed dose. The latter is not a quantitiy
created to evaluate risk. Thats why it can be used with all sorts of
materials in addition to living humans. Risks are more properly
evaluated through the effective dose equivalent. Because the latter
is created for the purpose of radiation protection, we can play all
sorts of games with it that take into account the sensitivity of the
irradiated tissue.

The implied arguement that two individuals of different masses
receiving the same effective dose equivalent would experience
different risks is a legitimate.  But in view  of all the other
uncertainties and variables, its not really a significant issue.

Non?

Regards

Paul Frame
Professional Training Programs
Oak Ridge Associated Universities
framep@orau.gov