Ethics of testing pesticides on humans questioned by scientists and politicians

How much pesticide was used on the apple you ate for lunch yesterday? Was it a safe amount? Are you sure?

Recently, scientists, ethicists and policy makers met at the New York Academy of Sciences in Manhattan. Their topic of discussion was the pesticide industry's use of human subjects to evaluate the health ramifications of their products.

Pesticides have traditionally been tested on rodents. The results of these tests were then extrapolated to humans in two ways. First, the safe rodent level of pesticide was divided by a factor of 10 to account for the transition from rodents to humans.

This level was then divided once again by a factor of 10 to encompass the variability of pesticides' effects among humans with differing sensitivities. Thus human safe levels used 100 times less chemicals than the rodent safe levels.

In 1996, Congress passed a law named the Food Quality Protection Act (FQPA). The FQPA made it necessary for the Environmental Protection Agency (EPA) to apply a child protective safety factor to the current safe levels. This factor (also a division by 10) meant that the safe exposure level was now 1,000 times less than the rodent level.

Since the passing of the FQPA human testing has increased enormously.

"We believe that the reason they are doing the testing in humans is so that they can basically use the human data to justify more relaxed pesticide standards that would permit the application of higher amounts of pesticides to the foods that we eat," according to Dr. Philip J. Landrigan, a pediatrician at Mount Sinai School of Medicine and director of the Mount Sinai Center for Children's Health and the Environment.

Essentially, by testing on humans it is believed that the pesticide industry is avoiding the first division by 10 in the safe levels of the pesticides - the one stemming from the transition from rodent to human.

The testing, being done outside of the United States, easily attracts participants, despite its potentially damaging effects.

According to Dr. Herbert L. Needleman, a professor of pediatrics at the University of Pittsburgh in Pennsylvania, testing firms in Scotland will pay college students as well as other jobless people up to $600 per day for the testing. The testing which can last up to 18 days consists of the ingestion of organophosphates, the chemicals used in pesticides, fertilizers and nerve gas.

While the use of human test subjects to achieve less safe levels presents ethical dilemmas, the act of testing on human subjects alone raises ethical questions.

While past studies have, at times, used human subjects, there is a generally accepted standard to which the testers conform. According to Dr. Mary Faith Marshall, a professor of bioethics at the University of Kansas Medical Center in Kansas City, these standards require that the research subject is completely aware of any potential risks stemming from the procedure.

Moreover, claims Marshall, it is critical that the research is important enough to warrant human testing because, "If not, researchers shouldn't even be doing the study in the first place."

Whether or not human testing should be done has been a point of debate for quite some time. Currently the EPA does not have standards governing human pesticide testing, according to Dr. Lynn R. Goldman, a professor of public health at Johns Hopkins Bloomberg School of Public Health.

"This leaves the whole issue wide open for abuse...and, in a way, constitutes an encouragement for companies to do (these kinds) of studies," said Goldman.

In 1998, the EPA placed a moratorium on the acceptance of data establishing toxicity levels for pesticides gathered through human testing.

The Bush administration initially reversed that decision. However, due to public outcry the administration was forced to reinstate the moratorium and turn the matter over to the National Academy of Science for further guidance.

The answer as to whether or not the studies are acceptable, does not even begin to resolve a much more important question. Are the studies scientific?

Dr. Landrigan quickly points out that "The testing that's being done is all being focused on young adults and therefore the data that are being generated really is not very relevant to the protection of infants and children."

In fact, some of the tests involve fewer than 20 people. By contrast, drug trials require thousands of people to establish safe levels.

On the other hand, Jay Vroom, president of the trade association CropLife America, which represents all the major manufactures, formulators and distributors of crop protection chemicals, adamantly defends the tests, "We believe that there is a very important place for human clinical tests for a wide range of risk assessment purposes as long as those tests are conducted in carefully controlled and ethically sound manner.our position about this kind of testing is that it is appropriate and a valuable tool for regulators to consider.