[ RadSafe ] pyrophoric uranium considered nonessential

[Herren, Roy WS.]

Dr. Raabe,

	If for the sake of argument, one were to give credence to the
possibility that there may well be world wide contamination from uranium,
isn't it most probable that the source of the majority of said contamination
would be from Naturally Occurring Radioactive Material (NORM) from multiple
centuries of utilizing Coal fired power plants, and cement kilns?  In my
humble opinion, I don't think that this is an unreasonable thesis given
recent evidence of world wide lead and mercury contamination from mankind's
activities.  If I recall correctly, there has been ice core evidence from
Green Land of wide spread lead contamination from early bronze age smelting,
and recent supposition of pacific ocean mercury sediment contamination from
eastern pacific coal fired power plants.  Therefore, presumed evidence of
wide spread uranium contamination can not necessarily be assumed to be
entirely from  recent military munitions activities utilizing depleted
uranium, but rather are most likely a result of mankind's pre and post
industrial revolution activities.

	Given the high temperature of a fire in a coal boiler or the
temperatures in a cement kiln, trace NORM in coal and limestone, and the
height of their associated smoke stacks, it would seem that history has
provided us with a ready made laboratory to examine James's thesis about the
effects of so called pyrophoric uranium.  Do down winders from said smoke
stacks experience millions of times greater than normal kidney or testicular
disease?  Clearly the answer is no!  Perhaps now we can get back to RADSAFE
issues, and leave the presumed toxicology issue behind.

-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl]On
Behalf Of Otto G. Raabe
Sent: Thursday, July 07, 2005 9:19 AM
To: James Salsman
Cc: radsafe at radlab.nl
Subject: Re: [ RadSafe ] pyrophoric uranium considered nonessential


At 10:05 PM 7/6/2005, James Salsman wrote:

>The temperature of a particle suspended in air has no bearing on
>whether or not it can be inhaled.  That is beside the point.
>
>After being thrust into air by a fire, a molecule of UO3(g) is not
>likely to collide with more than a few dozen other UO3(g) particles,
>and not likely to glom onto any of them until it has had a chance
>to cool, and further diffuse into air.  Based on detection patterns
>-- from http://www.bovik.org/du/Salbu-uranyl-detected.pdf and Dr.
>Johnson's and his colleagues' work -- UO3 readily plates on surfaces
>(and therefore lung tissue, where all particles smaller than 0.01
>microns are absorbed into the bloodstream immediately), but does not
>fall to the ground with the U3O8 and UO2 combustion product dusts
***********************************************************************
Apparently Mr. Salsman never studied aerosol science, and seems to think 
his imagination defines aerosol behavior. The facts concerning the actual 
characteristics of DU aerosols including UO3 and the actual biological 
risks thereof are well described 
in:  http://www.gulflink.osd.mil/du_ii      It is clear that the actual 
risks are minimal, and limited to kidney damage associated with really 
immense systemic intakes.

Airborne monomeric UO3 is not a gas at room temperatures and would 
agglomerate and/or attach quickly to other airborne dust particles and 
surfaces. The study by Salbu et al. (2205) that is referenced clearly 
refers to "UO3 particles". Although, UO3 is more readily absorbed into the 
blood than other oxides of uranium, its abundance under real conditions is 
apparently minimal.

Otto


**********************************************
Prof. Otto G. Raabe, Ph.D., CHP
Center for Health & the Environment
(Street Address: Bldg. 3792, Old Davis Road)
University of California, Davis, CA 95616
E-Mail: ograabe at ucdavis.edu
Phone: (530) 752-7754   FAX: (530) 758-6140
***********************************************  

_______________________________________________
You are currently subscribed to the radsafe mailing list radsafe at radlab.nl

Before posting a message to RadSafe be sure to have read and understood the
RadSafe rules. These can be found at:
http://radlab.nl/radsafe/radsaferules.html

For information on how to subscribe or unsubscribe and other settings visit:
http://radlab.nl/radsafe/