Common Pesticides Are More Dangerous Than You Know

A study published last year in the Toxicology journal added evidence to a growing body of research that shows glyphosate formulations such as Monsanto’s Roundup, are more toxic than glyphosate alone. The study directly questioned the regulators’ approval mechanisms and accused them of failing to properly identify pesticide risks.

The study, conducted by Robin Mesnage, Benoît Bernay and Professor Gilles-Eric Séralini, from the University of Caen, France, focused on glyphosate herbicides — the most widely used method of weed control in the United States and one of the most widely used worldwide.  EPA estimates from 2007 show that 180 to 185 million pounds of glyphosate were used for U.S. agriculture and an additional 8 to 11 million pounds were used for non-agricultural purposes.  Glyphosate is often used in tandem with genetically engineered glyphosate-resistant crops sold by Monsanto.

Few people are aware that for purposes of regulatory risk assessment, typically it is the active ingredient, not the entire herbicide formulation or its separate components, that is tested. The marketed glyphosate formulations, however, also contain other ingredients called adjuvants (or surfactants), identified somewhat misleadingly as “inert” since they are added to enhance the stability and penetration of the active ingredient into cells. In this study the researchers looked at the toxicity of pesticide adjuvant POEA, which they found to be toxic to human cells.

Although additional studies are needed to show the impact of glyphosate formulations on humans and other terrestrial animals in situations approximating real life exposure, previous studies have already demonstrated the toxicity of Roundup, and in particular, Roundup with POEA, to amphibians, fish, and aquatic invertebrates.

The regulatory failure to demand testing of inert ingredients that may be adding to product toxicity in formulations poses a serious environmental and occupational threat. And while glyphosate has been approved by regulatory bodies worldwide, this study demonstrates why concerns over its effects on human and animal health persist after decades of use.

In a press release, CRIIGEN (Committee for Research and Independent Information on Genetic Engineering), an organization where Professor Séralini serves as the president of the scientific board and which provided structural support for the study, urged that, “[t]he complete formulations must be tested in long-term toxicity studies and the results taken into account in regulatory assessments.”

Last year, another one of Prof. Séralini’s study was hotly debated after it questioned, among other things, the adequacy of the standard 90 day feeding trials for evaluating GMO maize and Roundup since its own findings discovered tumors in study animals four to seven months into the study.