RE: More on DU

["Caracappa, Peter F (CRD)" <caracappa@crd.ge.com>]

Two items that you have not considered that the IH people might have:  first of all, not all of the
particulates inhaled will become absorbed in the body.  As a matter of fact, for an element as heavy
as uranium, I would expect the uptake to be very low, though I haven't had a chance to look up any of
the data to verify that.  Also, I can't tell if you've taken into account the organ dose/effective
dose relationship or the fact that the total body biologically half life for uranium is only 100
days.

And according to our friends at Sigma-Aldrich, working in any detectable concentration of uranium
should require a self-contained breathing apparatus with a full facepiece and operate in a
pressure-demand mode.  If this guy was cleaning tanks unprotected, there was a serious occupational
safety shortfall somewhere along the line...

g GE Corporate Research & Development
______________________________________________
Peter F. Caracappa
Environment, Health, and Safety
Tele: 518-387-4221  Dial Comm:  8*833-4221
Fax: 518-387-6335
email: caracappa@crd.ge.com

	I calculated an Annual Limit of Intake (inhalation) of 32Bq, which
	corresponds to 2100microgram of DU for members of the public (1mSv/yr
	limit). At 2000 hr per year and a breathing rate of 1.2m3/hr, you obtain a
	Derived Air Concentration (DAC) of 0.013 Bq/m3 which corresponds to
	0.88microgram/m3. This is a factor of 227 times more restrictive than the
	ACGIH limit.
	
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