Faced with a barrage of criticism over studies in which companies dose people with pesticides to determine chemical toxicity, the Environmental Protection Agency (EPA) is seeking outside advice. On 14 December, the agency asked the National Academy of Sciences (NAS) to help it decide whether it should accept these controversial data.
A law passed in 1996 set new safety limits for pesticides on produce. Consequently, industry researchers have increasingly exposed paid volunteers to pesticides in order to determine the minimum level of a toxicant that causes effects such as headaches, nausea, and changes in the activity of enzymes in the blood. Although companies say human experiments are preferable to animal studies in setting realistic standards, these kinds of tests remain controversial. Clinton-era EPA chief Carol Browner barred the agency from using human data after activists argued that the tests--unlike drug trials--offer no potential health benefit to the participants. And an EPA advisory panel that wrestled with the issue for more than 2 years (Science, 1 January 1999, p. 18) condoned some human pesticide studies but advised against the minimum-response tests.
EPA revived the controversy late last month when it announced that the agency had resumed reviewing some human pesticide data and would develop a policy for such tests. On 14 December, in an about-face, EPA announced it will shelve such studies until NAS weighs in. The agency wants to know, for example, whether some toxicity research on humans should be considered "unacceptable" and how it should evaluate studies that weren't done under the ethical guidelines that govern federally funded research.
Outsiders say the agency should formulate official guidelines for human studies if it is going to encourage them. Bioethicist Arthur Caplan of the University of Pennsylvania in Philadelphia, a member of the advisory panel, says EPA is "desperately in need of a policy."