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Old 12-08-2003, 01:33 AM
Bill Oliver
 
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Default What's The Latest On Roundup Herbicide?

In article ,
paghat wrote:
N. Vigfusson & E. Vyse in MUTATION RESEARCH, v.79 p.53-57, found
that glyphosate has a genetic mutagenic effect on human lymphic cells. To
Monsanto of course that translates "unproven for cancer," but what it
really shows is that glyphosate at least sets in motion conditions that
result in nonhodgson's lymphoma, as further shown to be the situation by
L. Hardell & M. Eriksson in "A Case-Control Study of Non-Hodgkin
Lymphoma" in the JOURNAL OF THE AMERICAN CANCER SOCIETY,
March 15, 1999. A conservative assessment of these studies would indicate
further study is needed to be sure the indicators, at this point being ALL
against glyphosate, can always be substantiated; but the studies could be
done fifty times with the same outcome & it would still be unproven by
Monsanto's standard of lying & propogandizing.



Of course, when you use near-lethal doses of *anything,* one can induce
mutagenic effects. Using this criteria, table salt is a deadly
poison. In one recent study, in order get teratogenic effects, rats
were fed 1000 mg/kg of Roundup, which is the LD50. Sure enough, 50%
died, and those that did not die had funny-looking babies. (Dallegrave
E, Mantese FD, Coelho RS, Pereira JD, Dalsenter PR, Langeloh A. The
teratogenic potential of the herbicide glyphosate-Roundup in Wistar
rats. Toxicol Lett. 2003 Apr 30;142(1-2):45-52.) This is consistent
with multiple studies over the past two decades. But then, even
Monsanto doesn't suggest that you eat 1000 mg/kg/day of the stuff.

And, of course, the lymphocyte studies you mention use the single worse
criteria for genetic damage -- sister chromatid exchange -- which can
be caused by osmotic effects as easily as the test substrate. The study
you mention by Vigfusson in 1980 used such high doses that most cells
died outright. The results were not dose-related and were not
internally consistent (i.e. cells from the same donor showed a response
in one run and no response in another). The authors themselves wrote
that their dose was so high that cytotoxicity was a confounding
factor. Even were the results positive, the meaning of
sister chromatid exchange is not known. If one looks at the myriad
*other* mutagenicity studies that have been done, the picture is very
different. Roundup is nonmutagenic at reasonable doses in repeated
studies involving bacterial mutation assays, HGPRT locus studies,
chromosome breakage studies, and others. There is one chromosome
breakage study that found positive results at levels 70 times lower
than most others, but used an unaccepted method, including incubating
the cells in the substrate for 72 hours (where the OECD and EEC
accepted method is 4 and 20 hours). Further, cytologic morphologic
evaluation showed cytotoxicity, again making the results questionable.
Killing cells always results in chromosome breaks. This study was also
inconsistent in that it found breaks in human cells but none in bovine
cells.

The bottom line is that the studies that show effects are invariably
those that are done in conditions where most of the cells are dying
anyway -- from such a high dose, from osmotic stress, etc. Smashing
in someone's skull with a hammer is not a test of iron toxicity.


In fact, studies which look at real criteria repeatedly have found that
it is safe when used properly. For instance, a more recent analysis
from the Department of Pathology, New York Medical College (Williams
GM, Kroes R, Munro IC, Safety evaluation and risk assessment of the
herbicide Roundup and its active ingredient, glyphosate, for humans.
Regul Toxicol Pharmacol. 2000 Apr;31(2 Pt 1):117-65. ) found:



The oral absorption of glyphosate and AMPA is low, and both
materials are eliminated essentially unmetabolized. Dermal
penetration studies with Roundup showed very low absorption.
Experimental evidence has shown that neither glyphosate nor AMPA
bioaccumulates in any animal tissue. No significant toxicity
occurred in acute, subchronic, and chronic studies. Direct ocular
exposure to the concentrated Roundup formulation can result in
transient irritation, while normal spray dilutions cause, at most,
only minimal effects. The genotoxicity data for glyphosate and
Roundup were assessed using a weight-of-evidence approach and
standard evaluation criteria. There was no convincing evidence for
direct DNA damage in vitro or in vivo, and it was concluded that
Roundup and its components do not pose a risk for the production of
heritable/somatic mutations in humans. Multiple lifetime feeding
studies have failed to demonstrate any tumorigenic potential for
glyphosate. Accordingly, it was concluded that glyphosate is
noncarcinogenic. Glyphosate, AMPA, and POEA were not teratogenic or
developmentally toxic. There were no effects on fertility or
reproductive parameters in two multigeneration reproduction studies
with glyphosate. Likewise there were no adverse effects in
reproductive tissues from animals treated with glyphosate, AMPA, or
POEA in chronic and/or subchronic studies. Results from standard
studies with these materials also failed to show any effects
indicative of endocrine modulation. Therefore, it is concluded that
the use of Roundup herbicide does not result in adverse effects on
development, reproduction, or endocrine systems in humans and other
mammals. For purposes of risk assessment, no-observed-adverse-effect
levels (NOAELs) were identified for all subchronic, chronic,
developmental, and reproduction studies with glyphosate, AMPA, and
POEA... Acute risks were assessed by comparison of oral LD50 values
to estimated maximum acute human exposure. It was concluded that,
under present and expected conditions of use, Roundup herbicide does
not pose a health risk to humans.




When one begins to accumulate peer-reviewed studies, it soon becomes
obvious that the vast majority indict RoundUp's allegedly "safe as salt"
key ingredient as a threat to the environment & to human health.


Quite the opposite. Repeated studies have shown that it is very
safe. The presence of toxicity at very, very high doses in rats
does not contradict this.



In
Australia it is already banned for use near wetlands.


Litigation is not science. Political agendas are not
a substitute for real science.



When one finds "positive" studies they turn out not to be peer
reviewed, & were either done at Monsanto labs, written by
Monsanto propogandists, were Monsanto-funded studies & did
not qualify for publication in peer-reviewed journals.



This is, of course, circular. Anybody who writes an article
that shows the safety of Roundup is dismissed as a "Monsanto
propagandist."


billo