From a mass email, dated December 18, 2012, sent out by Jeffrey Smith of Institute for Responsible Technology:
On a South African farm growing GM corn, reports indicated that as many as 1-2 workers died each month while eating the corn as the main staple of their diet—three times a day. Many of the 50–60 workers fell ill—with flu-like symptoms, headaches, and inflammatory disorders—forcing the farm to employ 20% more people to make up for the sick days.
When the farmer switched to non-GM corn as a desperate attempt to counteract severe animal disorders, the health of both the animals and the workers improved dramatically. When he ran out of non-GM corn and had to use GM corn, the health problems reemerged—until the farmer secured non-GM corn once again.
According to a former Monsanto scientist, when his colleagues discovered that GM corn damaged the health of rats, they hid the evidence by rewriting the study. He was especially concerned that if the rats got sick eating a relatively small percentage of corn in their diet (e.g. up to 33% for 90 days), what does that mean for native Southern Africans who eat corn as the vast majority of their calories every day.
For more information, please go to: http://responsibletechnology.org/gmo-education