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Scientific Panel Backs Testing of Toxins on Humans By Judith Graham, Chicago Tribune Knight Ridder/Tribune Business News Posted on Fri, Feb. 20, 2004 Feb. 20 - A panel of scientists and ethicists recommended Thursday that the government accept research that tests the effects of pesticides and other toxic substances on humans. Such research--typically conducted by chemical and pesticide companies--could be used to set safety standards for potentially poisonous substances in the food supply and in the nation's air and water, said a 14-member commission convened by the National Academy of Sciences. Noting the sensitivity of the issue, the panel suggested strict ethical and scientific standards for the research and said "the utmost caution" should be exercised in considering results. Critics immediately decried the panel's decision, arguing that it opened the way to questionable science and could lead to large numbers of studies that test toxins on people. Eventually, standards for allowable pesticide levels in food and water could end up being relaxed, critics warned. "We're concerned that the chemical industry is going to view this as a green light," said Richard Wiles, senior vice president of the Environmental Working Group. For their part, chemical companies say the human studies could contribute valuable data on what levels of pesticides and other toxins can be safely used in agriculture and industry. Animal studies alone are sometimes not sufficient to answer questions such as what doses people can tolerate without ill effects, they note. "Is every pesticide now going to have human clinical data? We don't believe so," said Jay Vroom, president of CropLife America, a group that represents pesticide manufacturers. "This kind of refined human data would rarely be needed." Since 1998, the U.S. government has refused to use chemical research on humans in its environmental decision-making, noting significant disagreement over whether such research could be conducted ethically. Two years ago it looked to the National Academy, which provides science advice to the government under congressional charter, to give guidance. The academy's panel decided human research involving toxins was acceptable only if it was conducted with scientific rigor, caused minimal or no harm to participants and answered important scientific questions that could not be resolved by animal experiments. All such research should undergo extensive evaluation by scientific review boards and also be reviewed by a separate, high-level group at the Environmental Protection Agency, it said. Now the issue goes to the EPA. The agency plans to issue a formal proposal in the next few months, said Dave Deegan, a spokesman. The commission's 179-page report sheds light on a little-known research practice. To evaluate how people respond to their products, chemical and pesticide companies recruit volunteers to ingest toxins over a course of several weeks or months and allow their physiological responses to be monitored. There are no laws prohibiting these practices. Participants are usually paid several hundred dollars or more. To many, this kind of research brings to mind the abominations of Nazi Germany, whose scientists conducted a variety of tests on prisoners during World War II. "Is asking people to take a poison ever justified?" asks Vera Sharav, president of the Alliance for Human Research Protection in New York. "If [the Nazis] taught us anything, it is that the answer has to be no." After the war, standards for human research were developed internationally and in the United States to prevent abuses. Ethical concerns about subjecting people to toxins remained contentious. These concerns helped slow chemical studies to a crawl in the 1980s. In 1996, Congress enacted the Food Quality Protection Act, which significantly tightened safety standards for pesticides in light of growing evidence that they could be harmful to children. Previously, standards had required that allowable human levels of pesticides be one-one hundreth of the level shown to have no adverse effect on animals. The act changed the standard to one-one thousandth, and pesticide companies were faced with the prospect of having their products pulled off the market. That inspired pesticide manufacturers to conduct human tests, largely to see if they could produce convincing evidence that the stricter standards weren't needed because humans appeared to be able to tolerate higher doses of chemicals without adverse effects. One such study, sponsored in 1997 by Amvac Chemical Corp., involved dichlorvos, which is used in flea collars. It called for six volunteers to receive a 35 milligram dose of the pesticide in corn oil once a week for two weeks and then to get 15 consecutive daily 21 milligram doses. The purpose was to measure how the pesticide inhibited a certain enzyme. Blood samples and urine were collected and analyzed at regular intervals. Information about the study was supplied by the Environmental Working Group, which has a copy of the protocol and helped bring human experiments involving pesticides to light in a groundbreaking 1997 study. Another study, described by the Omaha World-Herald in 1999, recruited 60 volunteers who were each paid $460. About half were given a capsule containing chlorpyrifos, a widely used pesticide also known as Lorsban or Dursban. Some had symptoms that included nausea, vomiting, abdominal and chest pain, and shortness of breath. About half served as a control group. Earlier that year, the EPA had concluded that chlorpyrifos disrupted the central nervous system and could pose a significant health risk. In another example, a 2000 study at Loma Linda University in California recruited 100 adult volunteers to swallow a pill containing perchlorate, a toxic element of rocket fuel, every day for six months. Participants were paid $1,000 for following the regimen and allowing blood, urine and thyroid tests. Information about the study was supplied by the Environmental Working Group. Altogether, 19 human research studies involving pesticides have been conducted since 1992, according to the National Academy's study. The report did not give details on company sponsors or how many people were involved. "At the levels of exposure these trials are conducted at, they are associated with very minute changes in blood chemistry and physiological function--about the equivalent of drinking a cup of coffee," said Vroom, of CropLife America. Dr. Alan Lockwood, a neurologist at the University of Buffalo and a spokesman for Physicians for Social Responsibility, asks, "How can we determine what's safe or not" in experiments that typically last several weeks or months and have virtually no follow-up? Given new research that shows pesticide exposure linked to Parkinson's disease-type conditions later in life, "I don't think we know," Lockwood said. Research on children or pregnant women is not expressly prohibited in the National Academy committee's recommendations. The failure to exempt children from testing is "appalling," said Erik Olson, senior attorney with the Natural Resources Defense Council. Members of the National Academy committee said tests on children were highly unlikely, given the rigor of the standards for human research on toxic substances that they are recommending. "We didn't imagine such a thing in the test because we couldn't imagine it," said Ellen Wright Clayton, professor of genetics and health policy at Vanderbilt University and a commission member. ----- SOURCE: Miami Herald, FL http://www.miami.com/mld/miamiherald/business/national/8000221.htm * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn