[ RadSafe ] Miller and McClain, 2007

[Steven Dapra]

At 01:10 PM 7/3/08 -0700, James Salsman wrote:

>Here are some quotes from Alexandria C. Miller and
>David McClain (2007) "A Review of Depleted Uranium Biological Effects:
>In Vitro and In Vivo Studies" Rev Environ Health 22(1) 75-89:



July 4

         James Salsman (JS) presented us with some quotes from a paper by 
Miller and McClain that he appears to believe suggest or prove that 
depleted uranium is harmful.  One of JS's quotes has Miller and McClain 
invoking McDairmid et al. (2004) as saying: "McDairmid et al (2004), in 
their 10-year follow-up of 39 veterans exposed to DU in friendly fire 
incidents during the 1991 Gulf war, reported that the study participants 
exposed to the highest levels of DU showed a statistically significant 
increase in chromosomal aberrations as compared with low-exposure groups."

         These are not the exact words of McDiarmid et al., this is how 
Miller and McClain summarize them.  What about McDairmid et al., (2004)?

         I located their paper (Health Effects of Depleted Uranium on 
Exposed Gulf War Veterans: A 10 Year Follow-up) on line. I'll present some 
quotes from it, and discuss them.

         "Baseline CAs [chromosomal aberrations] were statistically 
different, with the high uranium group displaying a higher, but minimally 
different, CA frequency per cell. This difference was not observed in 
previous surveillance rounds. Due to the limited number of chromosomal 
aberrations observed, it was not possible to use regression to assess its 
relationship with ln urine uranium or a method to test for the persistence 
of the relationship despite the presence of confounders. However, the 
association between chromosomal aberrations and urine uranium observed here 
does not appear to be the result of smoking, exposure to mutagens, or age 
in this cohort, since none of these were found to be significantly 
associated with either average chromosomal aberrations or urinary uranium 
levels."  (from p. 289)  (Note:  ln means log normal.)

         According to McDiarmid et al., so few chromosomal aberrations were 
found that they couldn't perform linear regression on them.  How can there 
be a "statistically significant increase" when the aberrations can't even 
be analyzed?

         Also:  "In two previous observations, no differences in 
chromosomal aberrations (CAs) were noted between the high and low uranium 
groups, although there was a statistically significant increase in SCE 
observed in the high uranium group in the last evaluation (McDiarmid et 
al., 2001) . . .."     (from p. 293)

         This statistically significant increase was found in sister 
chromatid exchanges, not in chromosomal aberrations.

         McDiarmid et al. note "a statistical difference in CAs (higher in 
the high U group)."  They do not say it's significant, only that it's 
different.  According the next sentence, "This is, however, based on close 
to normal absolute frequencies of CAs per cells."

         Look at that, James  a "normal" frequency, not a statistically 
significant one.

         McDiarmid et al. also write:  "Because multiple outcomes are being 
examined, there exists the risk that statistically significant findings may 
be observed by chance alone. Although the kidney is the putative "critical" 
target organ for uranium toxicity under acute and chronic exposure 
conditions, no evidence of renal dysfunction (glomerular or tubular) was 
found. The biomarkers for proximal tubule dysfunction, the presumed target 
of uranium, showed minimal differences between the groups."  (p. 292; 
citations omitted.)

         I think this speaks for itself about any so-called statistically 
significant increase.  I would like to emphasize the authors' statement 
that no damage was found in the kidneys.  In light of that, I rather doubt 
that exposure to depleted uranium, or any type of uranium, did any damage 
anywhere else.  The authors also say that since they only studied 39 
veterans, "the power to detect subtle effects is low."

         Earlier today, James, in response to my request for your CV, you 
wrote, "The only pertinent qualification is the ability to read reports of 
actual
experiments . . .."  If you'll pardon me for saying so, it has become 
patently obvious to me that you *can't* read reports.

Steven Dapra


REFERENCE

McDiarmid, et al. Health Effects of Depleted Uranium on Exposed Gulf War 
Veterans: A 10 Year Follow-up. Journal of Toxicology and Environmental 
Health, Part A 67:277-296; (2004).

         Available on line at:

< www.pdhealth.mil/downloads/Env_Health%20Effects_DU.pdf>.