Show that there is a risk, with serious, peer reviewed studies, and USDA/FDA/EPA will require labeling, or prohibit the product entirely. But once a product has been tested and approved for safety, the burden of proof is on the accuser.
This is one of the areas where junk science is epidemic. There is a substantial cottage industry of advocacy groups pumping out "studies" that don't meet elementary scientific standards. But the press jumps on them, and we're off to the races. If we had a way to attach punitive damages to such false accusations, Monsanto would have a whole new profit center.
http://farmwars.info/?p=10833#more-10833
GM-fed females had on average a 25% heavier uterus than non-GM-fed females, a possible indicator of disease that requires further investigation. Also, the level of severe inflammation in stomachs was markedly higher in pigs fed on the GM diet. The research results were striking and statistically significant. Lead researcher Dr Judy Carman, adjunct associate professor at Flinders University, Adelaide, Australia,[2] said: Our findings are noteworthy for several reasons. First, we found these results in real on-farm conditions, not in a laboratory, but with the added benefit of strict scientific controls that are not normally present on farms.
Second, we used pigs. Pigs with these health problems end up in our food supply. We eat them.
Third, pigs have a similar digestive system to people, so we need to investigate if people are also getting digestive problems from eating GM crops.
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