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Strong Suspicions of Toxicity in One GMO Corn
By Stèphane Foucart
Le Monde
Tuesday 13 March 2007
Allowed to go on the market in France and Europe, MON 863, a
transgenic corn invented by Monsanto, has been at the center
of a controversy over its innocuousness for over two years (April
23rd, 2004, Le Monde). These debates could resume after the March
13th publication in "Archives of Environmental Contamination
and Toxicology" of a study suggesting this genetically modified
organism (GMO) is toxic to the liver and kidneys.
According to this work, consumption of MON 863 corn disturbs
numerous biological parameters in rats to a greater or lesser
extent: weight of the kidneys, weight of the liver, the level
of reticulocytes (new red blood cells), the level of triglycerides,
etc. Urinary chemistry is also changed, with reductions in excreted
sodium and phosphorus going as high as 35 percent. The effects
vary with the sex of the animals. "Female rats exhibit an
increase in blood fat and sugar levels, and an increase in body
weight - all associated with greater hepatic sensitivity,"
says Mr. Sèralini, principal author of this study and,
moreover, president of the Research Committee for Independent
Research and Information on Genetic Engineering (Criigen). "Among
males, the impact is opposite, with a drop in body and kidney
weights."
The authors of this work used data drawn from an experiment sponsored
by Monsanto, which bore on the study of 400 rats for 90 days.
The statistical treatment applied to these data by the experts
of the agrochemical firm was published in August 2005, by "Food
and Chemical Toxicology." That work brought to light significant
variations in biological parameters between animals fed MON 863
and those fed with its isogene - the same plant variety without
the genetic modification.
Monsanto researchers, for their part, had concluded that those
disparities were within the frame of the natural variability
of the measured parameters. The effects produced by the GMO were
therefore not considered pathological. As for the "natural
variability," it had been established by measuring the same
series of data on rats fed with other varieties of non-GMO corn,
with different nutritional values from MON 863 and its isogene.
The raw experimental data - over a thousand pages - were kept
confidential by the agrochemical firm until Greenpeace obtained
an order for its publication in spring 2005 from the Appeals
Court of Munster (Germany).
Criigen was thus able to examine the data in detail and to apply
a new statistical treatment to them. According to Mr. Sèralini,
that, notably, consisted of extracting from the raw data the
most significant effects specifically imputable to GMO absorption.
"Of the 58 parameters measured by Monsanto," the researcher
details, "all those that were altered concern kidney or
liver functioning." He continued, "furthermore, Monsanto
had deemed that, because the males and the females responded
differently, there was no reason for worry." He added, "Yet,
the liver, for example, is an organ that reacts differently as
a function of sex." In the same way, the fact that the measured
biological response was not always in exact correlation with
the dose of GMO received was interpreted by the company's experts
as proof that the transgenic corn being tested was not the cause.
Mr. Sèralini contests that principle: "When the disturbances
are hormonal, for example, the impact may not be proportional
to the dose."
Toxicologist Gèrard Pascal, a member, like Mr. Sèralini,
of the Committee on Bio-molecular Engineering, deems certain
that Criigen's conclusions are erroneous. "I reject the
analysis of the animals' weight curves, conducted without taking
their feeding into account," says Mr. Pascal. "But
I agree that the biological responses may vary between males
and females and with the principle that the effects of a GMO
corn must be compared with its isogene only and not take into
account effects produced by other corn varieties."
According to Mr. Pascal, the lack of direct correlation between
the GMO doses received and the impacts observed on the hepatic
parameters disqualifies the conclusions about liver toxicity.
Significant differences with respect to "kidney weight"
and "urinary sodium, phosphorus, and potassium" suggest
a renal impact. "However," Mr. Pascal recalls, "at
my request, the CGB pressed for investigations of the kidneys
and had not found any definitive evidence of toxicity" (December
15th, 2004, Le Monde). "The variations in the levels of
reticulocytes and eosinophiles (white blood cells) remain,"
adds M. Pascal. "I don't know how to interpret that, but
those are parameters that move around a lot in experiments."
As far as Mr. Pascal is concerned, the information developed
by Criigen is not of a nature to call into question the favorable
opinions delivered with respect to MON 863. "All that is
nothing but a personal interpretation," adds the toxicologist.
Criigen's work has been financed by Carrefour and Greenpeace,
but, as Mr. Sèralini explains, "Unfortunately, today
there is no public budget for conducting this type of research."
A situation all the more harmful, according to Mr. Sèralini,
in that, "the whole toxicological study ought to be redone,
controlling for hormonal dosages" and, above all, the tests
should be continued well beyond 90 days and on species other
than the rat to reach a definitive conclusion.
Translation:
t r u t h o u t French language correspondent Leslie Thatch
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