Some of the genetically modified soybean harvested in the southern Brazilian state of Paraná in 2005-2006 surpassed the limit of glyphosate herbicide permitted by the national health regulatory agency, Anvisa. “That is why the biotechnology companies operating in Brazil are opposed to labeling foods produced from genetically modified plants,” Valdir Izodoro Silveira, president of the Paraná Product Classification Company, linked to the state government, told Tierramérica.

The active ingredient in glyphosate and the residues of aminomethylphosphonic acid (the toxic byproduct produced in the degradation of the herbicide) were found in 70 percent of the 150 samples tested.

The maximum limit allowed by Anvisa is 10 milligrams per kilogram. Five percent of the contaminated samples had between 14 and 36 mg/kg. Another 60 percent had between 0.2 and 2.0 mg/kg.

In addition to the potential harm caused to consumers, between 2001 and 2006 there were 500 cases reported of farmers intoxicated by glyphosate in Paraná, Brazil's second leading soy-producing state, said Izodoro.