[ RadSafe ] Genotoxicity of U

[Otto G. Raabe]

>THE NATURAL FORMS OF URANIUM ART NOT REALLY VERYTOIXIC.

It is amazing how much crap can be published based on nothing more 
than wild imagination and hyperbole concerning uranium and DU.

While in graduate school at the University of Rochester I had the 
opportunity to observe the inhalation studies being conducted with 
uranium oxide using various animal species. The Rochester studies 
began in the 40's as part of the Manhattan project and were still in 
progress when I was a graduate student in the 60's. Two of the key 
papers summarizing the uranium dioxide inhalation studies were 
published by Leonard Leach and his associates. The references are 
Heath Physics  18: 599-612 (1970) and Health Physics 25: 239-258 (1973).

The opening sentence of the Abstract of the 1973 paper states: 
"Inhalation studies show that dogs, monkeys and rats can breathe a 
natural uranium dioxide (UO2) aerosol of approximately 1 um mass 
median particle diameter at a mean concentration of 5 mg U/m3  (25 x 
TLV or 28 x MPCa), for periods as long as 5 yr with little evidence 
of serious injury."   There is no major effect on the bronchial 
airways!. THESE WERE MASSIVE DOSES DELIVERED OVER SEVERAL YEARS!

Natural and depleted uranium are chemically and biologically 
identical in their behavior and radiologically very similar.  DU is 
not unique in any way. Uranium is present in all the soil and rock on 
the face of the earth, and small amount are in our food. There is 
over 70 years of excellent toxicological research on uranium and 
uranium oxide that seems to be ignored in recent  alarmist papers. 
Uranium oxide, the form to which people might be exposed is neither 
very toxic and nor a known carcinogen,

Kathren et al, beautifully summarized with extensive historical data 
the trivial toxicological properties of uranium. Kathren, Ronald L.; 
Burklin, Richard K., Health Physics. 94(2):170-179, February 2008, 
Acute Chemical Toxicity of Uranium.

Otto

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Prof. Otto G. Raabe, Ph.D., CHP
Center for Health & the Environment
University of California
One Shields Avenue
Davis, CA 95616
E-Mail: ograabe at ucdavis.edu
Phone: (530) 752-7754   FAX: (530) 758-6140
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