A genetically engineered product which has been cleared for use as food for humans and animals in China has shown signs of toxic effects on internal organs.

Laboratory rats, fed with a genetically engineered maize produced by Monsanto, have shown signs of toxicity in kidney and liver, according to a new study. The study, published in the journal "Archives of Environmental Contamination and Toxicology", analyzed results of safety tests submitted by Monsanto to the European Commission when the company was seeking authorisation to market its GE Maize variety MON863 in the EU.

The data shows that MON863 has significant health risks associated with it; nonetheless, the European Commission granted licences to market the maize for consumption by both humans and animals. The incriminating evidence was obtained by Greenpeace following a court case, and passed on for evaluation by a team of experts headed by Professor Gilles Eric Séralini, a governmental expert in genetic engineering technology from the University of Caen.

In a joint press conference with Greenpeace at Berlin, Professor Séralini said, "Monsanto’s analyses do not stand up to rigorous scrutiny – to begin with, their statistical protocols are highly questionable. Worse, the company failed to run a sufficient analysis of the differences in animal weight. Crucial data from urine tests were concealed in the company’s own publications"

Greenpeace is demanding the complete and immediate withdrawal of Monsanto’s MON 863 maize from the global market and is calling upon governments to undertake an urgent reassessment of all other authorised GE products and a strict review of current testing methods.

The data in question has been the subject of fierce debate since 2003, when significant changes were identified in the blood of tested animals fed on MON863. MON863 was approved by the European Commission, in spite of opposition by a majority of European Union member states, who raised concerns over the safety of the maize. Professor Séralini’s analysis now scientifically confirms these concerns. As the study states, "with the present data, it cannot be concluded that GM corn MON863 is a safe product." MON863 has already been authorized for markets in Australia, Canada, China, Japan, Mexico, the Phillipines, and United States.