Toxicologia Ambiental e Analítica

Teratogenic Effects of Glyphosate-Based Herbicides: Divergence of Regulatory Decisions from Scientific Evidence

Abstract

M Antoniou, MEM Habib, CV Howard, RC Jennings, C Leifert, RO Nodari, CJ Robinson and J Fagan

The publication of a study in 2010 showing that a glyphosate herbicide formulation and glyphosate alone caused malformations in the embryos of Xenopus laevis and chickens caused a scientific and political controversy. Debate centred on the effects of the production and consumption of genetically modified Roundup® Ready® soy, which is engineered to tolerate applications of glyphosate herbicide. This study, along with others indicating teratogenic and reproductive effects from glyphosate herbicide exposure, was rebutted by the German Federal Office for Consumer Protection and Food Safety, BVL, as well as in industry-sponsored papers. These rebuttals relied partly on unpublished industry-sponsored studies commissioned for regulatory purposes, which, it was claimed, showed that glyphosate is not teratogenic or a reproductive toxin. However, examination of the German authorities’ draft assessment report (DAR) on the industry studies, which underlies glyphosate’s EU authorisation, revealed further evidence of glyphosate’s teratogenicity. Nevertheless, the German and EU authorities minimized these findings in their assessment and set a potentially unsafe acceptable daily intake (ADI) level for glyphosate. This paper reviews the evidence on the teratogenicity and reproductive toxicity of glyphosate herbicides and concludes that a new and transparent risk assessment needs to be conducted by scientists who are independent of industry and of the regulatory bodies that were involved in the existing authorisation of glyphosate.