(Last updated July 2012)
Genetically modified (GM) corn line MON863 was approved for food use in Australia and New Zealand in December 2003 and April 2004 respectively. MON863 corn contains a gene that makes the plants tolerant to certain common insect pests, including corn rootworm. This variety of corn is suitable for growing in the northern hemisphere, in countries like the United States, where these pests cause damage to crops. Approval in Australia and New Zealand is necessary before any foods containing MON863 corn as an ingredient can be imported.
In 2004, the developer (Monsanto) released an animal feeding study using MON863 corn. In this study, which was not a traditional toxicity study, rats were fed a diet containing MON863 corn (test group) or conventional non-GM corn (control group) for 90 days. At the end of the study, no differences of toxicological significance were found between the two groups of rats. In particular, there was no indication of adverse effects in the rats that consumed the diet containing MON863 corn.
The European Food Safety Authority (EFSA) also examined the results of the study and released a positive scientific opinion in April 2004, concluding “the placing on the market of MON863 is unlikely to have an adverse effect on human and animal health or the environment in the context of its proposed use”.
Monsanto published their results, including a detailed statistical analysis of data obtained from the study, in the journal Food and Chemical Toxicology in 2006.
Claims made by Professor Gilles-Eric Séralini
Professor Gilles-Eric Séralini, of the University of Caen, and colleagues in France have published several journal articles claiming to have found evidence suggestive of adverse effects in rats fed on a diet containing MON863 corn, and other GM corn varieties. In one article, the authors claimed their analysis showed “new side effects linked with GM maize consumption, which were sex and often dose-dependent”, particularly associated with the kidneys and livers of the rats that consumed the GM diet. The authors also argued that there is a need for longer-term feeding experiments in at least three animal species, including multi-generation reproductive studies.
These claims have been dismissed by regulatory agencies including FSANZ and EFSA and have been criticised by independent scientists, because the authors have drawn conclusions based solely on their statistical re-analysis of the original feeding studies. Robust toxicological analysis does not rely solely on statistics to determine treatment-related effects. For each study re-analysed by Séralini and co-workers, there was a notable absence of corroborating evidence that would lead independently to the conclusion that there were real effects of toxicological significance.
Despite widespread criticism of their methods, Professor Séralini and co-workers have failed to acknowledge that biological context is an integral step in the process of interpreting toxicity studies. FSANZ remains confident that the apparent changes reported by the authors in each case represent nothing more than normal background variability. Given the authors' failure to add scientific weight to their claims, FSANZ found no grounds on which to change the conclusion of safety assessments completed on several varieties of GM corn, including MON863 corn, and reaffirmed approval of these foods.
Results of a 90-day safety assurance study with rats fed grain from corn rootworm-protected corn (Food and Chemical Toxicology)