Re: Newspaper article on Plutonium

[Bernard L Cohen <blc+@pitt.edu>]

> 
> The quotes from the works of Helen Caldicott about plutonium toxicity are
> all wrong. Of course, she is referring to Pu-239 rather than Pu-238. The
> specific activity of Pu-238 is about 270 times that of Pu-239. Seventy-two
> pounds is about 560,000 Ci. The only model that will lead to the suggested
> large risk is assuming that in which all of the Pu-238 is converted to
> respirable small particles and they will all miraculously end up inside the
> lungs of people on the earth. 560,000 Ci / 5,000,000,000 people on earth =
> 110 microcuries per person. That would be bad, but it is obviously
> impossible. The problem with this model is "delivery".

    --The volume of air in the Earth's atmosphere is 5E18 cubic meters,
whereas the amount of air inhaled annually by people is 1E4 /year-person x
6E9 persons = 6E13 cubic meters/year. Thus, only 1/100,000 of the air is
inhaled by people each year.

> This is equivalent
> to saying that there is enough water in the great lakes to drown everyone
> who lives in Chicago.
 	--I haven't calculated it, but I would bet there is enough to
drown the whole population of the Earth many times over.

> 
Bernard L. Cohen
Physics Dept.
University of Pittsburgh
Pittsburgh, PA 15260
Tel: (412)624-9245
Fax: (412)624-9163
e-mail: blc+@pitt.edu