Bayer, the German chemicals and drugs giant, is pushing for a change in international convention to allow companies to conduct pesticide and GM tests on human beings.
The Leverkusen-based company is believed to be central to efforts to persuade the US Environmental Protection Agency (EPA) to reverse its longstanding ban on accepting data from human studies. US government sources believe a decision could be a few months away.
The ban is in place as a result of the post-Second World War Nuremburg Code and various federal laws. If the ban were undermined, the way would be clear for other companies to conduct and submit data based on such studies. Already, there are 10 other human pesticide studies awaiting EPA consideration from a variety of companies.
European environmental groups also fear that once the US authorities had caved in, similar changes would be forced on this side of the Atlantic. Although the issue under discussion centres on pesticides, Bayer's efforts are also understood to be linked to its considerable interests in genetically modified crops. Since its recent purchase of Aventis crop science, Bayer has become one of the world's largest GM producers, and currently conducts 85 per cent of UK field tests.
Bayer's role in the debate, described by the EPA as "under review as we speak", arises from data from a pesticide test conducted on humans four years ago. In 1998 eight volunteers in Scotland were exposed to small quantities of azinphos methyl, a pesticide of which Bayer is the world's largest producer.
The tests have come under heavy fire from one of America's largest lobbying groups, the Natural Resources Defense Council. A spokesman explained: "There is strong evidence that Bayer did not obtain fully informed consent because the subjects lacked knowledge and comprehension of the goals and risks."
Now that Bayer has the results of the test, it is keen that they should be used to assess the risks of its pesticides. Until now, the EPA's position has been to reject such studies as unethical and scientifically unnecessary. But statements by the EPA's administrator, Christine Whitman, strongly suggest that the position could soon change. She has now appealed to the US National Academy of Sciences to give its input on the subject.
Bayer's chief motive for pushing to end the ban is that it would loosen safety thresholds on pesticides. They are currently tested on animals, and released for sale at a 10th of the harmful strength. If the same practice were applied to human tests, stronger pesticides could be sold.