[ RadSafe ] uranium smoke is a teratogen

Steven Dapra sjd at swcp.com
Sun May 25 19:55:43 CDT 2008


May 25

         James Salsman has objected to my not having read JL Domingo's 
paper "Reproductive and developmental toxicity of natural and depleted 
uranium: a
review."  [Reprod Toxicol. 2001 Nov-Dec;15(6):603-9.]

         The abstract of this paper reads:  "Although the biokinetics, 
metabolism, and chemical toxicity of uranium are well known, until recently 
little attention was paid to the potential toxic effects of uranium on 
reproduction and development in mammals.  In recent years, it has been 
shown that uranium is a developmental toxicant when given orally or 
subcutaneously (SC) to mice. Decreased fertility, embryo/fetal toxicity 
including teratogenicity, and reduced growth of the offspring have been 
observed following uranium exposure at different gestation periods.  The 
reproductive toxicity, maternal toxicity, embryo/fetal toxicity, and 
postnatal effects of uranium, as well as the prevention by chelating agents 
of uranium-induced maternal and developmental toxicity are reviewed 
here.  Data on the toxic effects of depleted uranium on reproduction and 
development are also reviewed."

         Note that until recently little attention has been paid to the 
uranium's possible adverse effects in mammals.  That would tend to suggest 
--- wouldn't it? --- that uranium isn't obviously injuring or killing 
people or animals and that from the outset it might not be much of a health 
problem.  Epidemiologists probably tend to confine their studies to 
substances or conditions that are having an obvious effect, or that can be 
plausibly connected with some health outcome.

         JL Domingo is popular with James Salsman/Ben Fore, and by doing a 
Google search I was able to locate one abstract of a paper, and one full 
text of a paper (each with  JL Domingo as a co-author) on the effects of 
uranium on mice, or on rats.  (He is the last co-author listed on each of 
the two papers.)  I will discuss each of these items (briefly, I hope).  At 
the end of this message I will present the citations, links and so 
forth.  All citations have been omitted from my discussion.

Discussion of the ABSTRACT:

         The title of the paper is "Influence of Chronic Exposure to 
Uranium on Male Reproduction in Mice."

         The study mice were treated with treated with five different doses 
of uranyl acetate dihydrate that was added to their drinking water.  "There 
was a significant but non-dose-related decrease in the pregnancy rate of 
these animals. Body weights were significantly depressed only" at one of 
the dose rates.  "The results of this investigation indicate that uranium 
does not cause any adverse effect on testicular function in mice at the 
concentrations usually ingested in the diet and drinking water, with a 
safety factor of more than 1000."

Discussion of the PAPER (which was an "Original Research Article.")

         The title of the paper is "Influence of Maternal Stress on 
Uranium-Induced Developmental Toxicity in Rats."

         From the Introduction:  "Although uranium (U) exposure can result 
in both chemical and radiological toxicity, in general, chemical toxic 
effects from uranium compounds occur at lower exposure levels than 
radiological toxicity."  (That chemical effects are seen before 
radiological effects is well known, however I believe it bears repeating.)

         This study exposed pregnant Sprague-Dawley rats to uranyl acetate 
dihydrate (UAD); and to stress, by restraining for rats for a certain 
period of time each day.

(From the "Results.")

         "No external, internal, or skeletal malformations, as well as 
external and internal variations, which could be attributed to uranium 
exposure or maternal immobilization were noted."  Also: "Although in 
relation to the control group the total number of fetuses with skeletal 
defects was significantly increased by uranium exposure, this increase was 
not dose-related."

(From the "Discussion.")

"However, in contrast to the results in mice no significant maternal 
toxicity was noted in rats at 1/20 of the LD-50 (0.415 mg/kg/day)."   The 
significance of this is the different effect of the UAD on different 
species.  Could the UAD also have a different effect on humans that it does 
on rats and mice?  The paper again acknowledges the different effects (on 
rats and mice), saying, "A comparison of the results of both studies 
indicates that mice are more sensitive than rats to the toxic effects of 
uranium during gestation."

         The paper ends by saying:

         "In summary, while the results of the present study in rats 
corroborate only partly some of the adverse effects of uranium exposure 
during gestation reported in mice, according to the overall data in both 
species, the results indicated that uranium is a developmental toxicant in 
mammals. Although most pregnant women are not currently exposed to uranium 
levels that could cause adverse effects on health, higher rates of uranium 
exposure have been reported for some populations (e.g., individuals who 
consume foods grown in areas with elevated concentrations of uranium in the 
soil, or subjects with elevated uranium levels in their drinking water). In 
turn, the military use of DU might be of concern as an additional source of 
exposure. On the other hand, if uranium exposures occur at levels that may 
provoke maternal toxicity, the potential adverse developmental effects 
could be enhanced by stress."

         Other than to say that studies on humans would have to tease out 
the effects of stress versus those of depleted uranium, there is no need to 
comment.

         Finally, since James Salsman/Ben Fore like to claim that depleted 
uranium, uranyl, etc., cause birth defects, according to the abstract of 
this paper, "No teratogenic effects were noted in any group."  Let me 
reiterate that this paper was co-authored by the JL Domingo whose paper in 
Reproductive Toxicology James/Ben has on several occasions derided me for 
not reading.

Steven Dapra


Link and publishing data for the Abstract:

<http://toxsci.oxfordjournals.org/cgi/content/abstract/16/4/821>

(1991) Fundam Appl. Toxicol. 16, 821829.
Received July 24, 1990; accepted December 28, 1990

Influence of Chronic Exposure to Uranium on Male Reproduction in Mice

Juan M. Llobet, Juan J. Sirvent, Arturo Ortega, and Jose L Domingo.

Laboratory of Toxicology and Biochemistry San Lorenzo 21, 43201 Reus, Spain 
Pathology Unit, School of Medicine, University of Barcelona San Lorenzo 21, 
43201 Reus, Spain


Link and publishing data for the Original Research Article:

<http://www.ebmonline.org/cgi/content/full/228/9/1072>

Experimental Biology and Medicine 228:1072-1077 (2003)

Influence of Maternal Stress on Uranium-Induced Developmental Toxicity in Rats
M. Luisa Albina, Montserrat Belles, Mercedes Gomez, Domenec J. Sanchez and 
Jose L. Domingo.
Laboratory of Toxicology and Environmental Health, School of Medicine, 
"Rovira i Virgili" University, 43201 Reus, Spain

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