Differential Effects of Glyphosate and Roundup on Human Placental Cells and Aromatase Sophie Richard, Safa Moslemi, Herbert Sipahutar, Nora Benachour, and Gilles-Eric Seralini Laboratoire de Biochimie et Biologie Moleculaire, USC-INCRA, Université de Caen, Caen, France Abstract Roundup is a glyphosate-based herbicide used worldwide, including on most genetically modified plants that have been designed to tolerate it. Its residues may thus enter the food chain, and glyphosate is found as a contaminant in rivers. Some agricultural workers using glyphosate have pregnancy problems, but its mechanism of action in mammals is questioned. Here we show that glyphosate is toxic to human placental JEG3 cells within 18 hr with concentrations lower than those found with agricultural use, and this effect increases with concentration and time or in the presence of Roundup adjuvants. Surprisingly, Roundup is always more toxic than its active ingredient. We tested the effects of glyphosate and Roundup at lower nontoxic concentrations on aromatase, the enzyme responsible for estrogen synthesis. The glyphosate-based herbicide disrupts aromatase activity and mRNA levels and interacts with the active site of the purified enzyme, but the effects of glyphosate are facilitated by the Roundup formulation in microsomes or in cell culture. We conclude that endocrine and toxic effects of Roundup, not just glyphosate, can be observed in mammals. We suggest that the presence of Roundup adjuvants enhances glyphosate bioavailability and/or bioaccumulation. Key words: adjuvants, aromatase, endocrine disruption, glyphosate, herbicide, human JEG3 cells, placenta, reductase, Roundup, xenobiotic. Environ Health Perspect 113:716-720 (2005) . doi:10.1289/ehp.7728 available via http://dx.doi.org/ [Online 25 February 2005] Address correspondence to G.-E. Seralini, Laboratoire de Biochimie, EA2608-USC INRA, IBFA, Université de Caen, Esplanade de la Paix, 14032 Caen, France. Telephone: 33-0-2-31-56-54-89. Fax: 33-0-2-31-56-53-20. E-mail: criigen@ibfa.unicaen.fr We thank M.-J. Simon for technical assistance, and F. Baudoin for secretarial assistance. For financial support we thank the Quality and Sustainable Development Department of Carrefour Group, La Fondation pour une Terre Humaine, CRII-GEN, Ad.Gene laboratory, La Ligue Nationale contre le Cancer, Comité du Calvados. We acnowledge student grants from the Ligue contre le Cancer (Comité du Calvados) (S.R.) ; Société Française d'Exportation des Resources Educatives (H.S.) ; the Human Earth Foundation and Fondation Denis Guichard (N.B.) . The authors declare they have no competing financial interests. Received 5 November 2004 ; accepted 24 February 2005. The full version of this article is available for free in HTML or PDF formats. |