Quel est l’élément déclencheur de la controverse ?

L’élément déclencheur de cette controverse est une étude publiée le 19 septembre 2012 par le professeur Gilles-Eric Séralini et son équipe concernant la toxicité du Roundup, un herbicide utilisé pour les cultures de maïs génétiquement modifié.

Cette publication a suscité l’intérêt, l’accord ou le rejet à une très large échelle (voir le graphique ci-dessous), tant chez le grand public qu’au sein du monde scientifique. Ce document, à charge, se veut la preuve des effets nocifs des OGMs. Sa validité scientifique –habituellement garantie par le comité de lecture de la revue publiant l’article- a fini par être infirmée par de nombreux acteurs concernés par les OGM, depuis le Haut Conseil des Biotechnologies jusqu’à de nombreux experts.

Voici l’abstract de l’article qui a déclenché la controverse présentée ici. (L’intégralité du texte est disponible ici, pour les abonnés ScienceDirect) :

Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize

Food and Chemical Toxicology

Volume 50, Issue 11, November 2012, Pages 4221–4231

par Gilles-Eric Séralini ^(a), Emilie Clair ^(a), Robin Mesnage ^(a), Steeve Gress ^(a), Nicolas Defarge ^(a), Manuela Malatesta ^(b), Didier Hennequin ^(c), Joël Spiroux de Vendômois ^(c)

^a University of Caen, Institute of Biology, CRIIGEN and Risk Pole, MRSH-CNRS, EA 2608, Esplanade de la Paix, Caen Cedex 14032, France

^b University of Verona, Department of Neurological, Neuropsychological, Morphological and Motor Sciences, Verona 37134, Italy

^c University of Caen, UR ABTE, EA 4651, Bd Maréchal Juin, Caen Cedex 14032, France

Abstract

The health effects of a Roundup-tolerant genetically modified maize (from 11% in the diet), cultivated with or without Roundup, and Roundup alone (from 0.1 ppb in water), were studied 2 years in rats. In females, all treated groups died 2–3 times more than controls, and more rapidly. This difference was visible in 3 male groups fed GMOs. All results were hormone and sex dependent, and the pathological profiles were comparable. Females developed large mammary tumors almost always more often than and before controls, the pituitary was the second most disabled organ; the sex hormonal balance was modified by GMO and Roundup treatments. In treated males, liver congestions and necrosis were 2.5–5.5 times higher. This pathology was confirmed by optic and transmission electron microscopy. Marked and severe kidney nephropathies were also generally 1.3–2.3 greater. Males presented 4 times more large palpable tumors than controls which occurred up to 600 days earlier. Biochemistry data confirmed very significant kidney chronic deficiencies; for all treatments and both sexes, 76% of the altered parameters were kidney related. These results can be explained by the non linear endocrine-disrupting effects of Roundup, but also by the overexpression of the transgene in the GMO and its metabolic consequences.

Anatomopathological observations in rats fed GMO treated or not by Roundup, and effects of Roundup alone. (illustration tirée de l’article)

Highlights

► A Roundup-tolerant maize and Roundup provoked chronic hormone and sex dependent pathologies. ► Female mortality was 2–3 times increased mostly due to large mammary tumors and disabled pituitary. ► Males had liver congestions, necrosis, severe kidney nephropathies and large palpable tumors. ► This may be due to an endocrine disruption linked to Roundup and a new metabolism due to the transgene. ► GMOs and formulated pesticides must be evaluated by long term studies to measure toxic effects.

Keywords

GMO; Roundup; NK603; Rat; Glyphosate-based herbicides; Endocrine disrupting effects

Continuer sur les souches de rats.

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