Goverment Watch ties, says John Trosko, a molecular geneticist at Michigan State University. He and Brian Upham, also of Michigan State, have already identified toxic activity in perfluoro-octanoic acid and perfluorodecanoic acid. In 1998, their published research showed that these compounds block cellto-cell communication and promote tumors. Analyzing fluorinated organic surfactants is a major challenge, says Steven Strauss, a Colorado State University chemist. Chemically, they are nonvolatile and very inert, which makes it difficult to separate or concentrate the compounds for analysis, he explains. Even isolating fluorinated surfactants from environmental samples is complicated because product formulation details are
confidential, says Field. Fluorinated surfactants in environmental samples also can be detected using 19F nuclear magnetic resonance, Mabury says. As part of an Organization for Economic Cooperation and Development initiative aimed at assessing the problem on a global scale, U.S. EPA's chemical control division began a review of production and importation records for new chemicals over the past 20 years, according to Barbara Leczynski, the chemicals branch chief who managed the review. Agency officials are meeting with those from 3M and DuPont, in an effort to promote voluntary action and to explore regulatory options, first for PFOS, then for perfluoro-octanal carboxylic acid. —REBECCA RENNER
NRC urges pesticide alternatives In the push to make food safer for children through bans on many widely used pesticides, farmers could lose their quick-fix methods of handling pest and disease outbreaks. Replacing these conventional chemical pesticides with safer management techniques is addressed in a new National Research Council (NRC) report. The report, The Future Role of Pesticides in U.S. Agriculture, released in July, promotes an ecologi-
Almond and walnut growers in California have eliminated insecticide use by planting cover crops to attract beneficial predators that control mites, worms, and scales.
cally based approach to coping with pests, similar to Integrated Pest Management (IPM). The report recommends government policies and increased research to foster alternatives to chemical pesticides such as natural ecosystem processes, biological control organisms and products, and pestresistant plants. But chemical pesticides, especially new ones, should continue to be used, in the NRC panel's view, because of the reduced environmental and health risks of new pesticides and the lack of affordable alternatives. IPM experts in integrated pest management say this message could have little effect on U.S. farmers, who are the users of pesticides first and foremost and are unlikely to change, given the government's poor track record at promoting alternative pest controls. Nonetheless, a real movement is afoot to switch to more ecologically based methods of pest control, thanks in part to the 1996 Food Quality Protection Act (FQPA), says Ann Sorensen, with American Farmland Trust, a nonprofit organization representing family farms.
EPA's Office of Research and Development (ORD) as the agency's "chief scientific and technical officer" was insufficient. "No single individual could reasonably be expected to direct a world class research program in ORD while also trying to improve scientific practices and performance throughout the rest of the agency," the committee writes. And because the ORD chief holds the same rank as the regulatory program officers, ORD's advice is routinely ignored by those developing policy. The report strengthens previous panel recommendations designed to enhance EPA's scientific stature and leadership by suggesting that ORD create the equivalent of endowed academic research chairs, to be offered to distinguished academic scientists who would work full-time at ORD national labs. In addition, EPA should no longer allow one individual to both manage a project and serve as its peer review leader, NRC writes.
Recycling computers Efforts to tame Europe's growing mountain of electronic waste took a big step forward in June when the European Commission proposed legislation that for the first time would require manufacturers to recycle obsolete equipment and eliminate certain hazardous materials from products ranging from computers to toasters. Originally drafted as one directive {Environ. Sci. Technol. 1999, 4 (6), 228-229A), the proposal was split to stem industrial opposition to the hazardous materials ban and recycling requirements. As it now stands, one directive would require that 60-80% of electronic waste be recycled by 2006.The other would order manufacturers to substitute less Continued on Page 375k
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Environmental News The FQPA requires EPA to reassess tolerance levels for pesticide residues on food to protect children, who, because of their small size and rapidly developing bodies, are more sensitive to pesticide exposures than adults [Environ. Sci. Technol. 1999, 33 (21), 445A). "Growers will probably lose the use of key pesticides such as the organophosphates and carbamates," Sorensen says. EPA has already banned certain uses of the organophosphates Dursban (chlorpyrifos), methyl parathion, and azinphos-methyl under the FQPA. Sorensen predicts that restrictions on pesticide use mean that farmers will have fewer weapons in their arsenal, leading to greater problems with pest resistance. "The more heavily a single strategy is used, the more problems you have," explains May Be-
renbaum, entomology professor at the University of Illinois-Urbana, and chair of the NRC report. "The take-home message of the report is that you need a diverse toolbox to manage pests." The report promotes an approach that the government has unsuccessfully advocated since 1972, according to Les Ehler, entomology professor at the University of California-Davis. In 1993, the Clinton administration set a goal for the year 2000 to practice IPM on 75% of cropland. The failure of the government to back its policies with funding is evidenced by die paltry 4-8% of cropland managed by IPM today, he says. The government should shift the debate to pesticide reduction, which can be readily measured, Ehler says. Environmentalists agree. Monica Moore, program director for
Pesticide Action Network North America, says she believes the NRC report does not place enough emphasis on pesticide use reduction. "The report should ask how quickly can we move away from reliance on dangerous compounds and what can we do to accelerate that shift," she says. Dale Shaner, coauthor of the NRC report and director of agricultural biotechnology with BASF, says that public perception of pesticide risk is much greater than what the environmental and health risks actually are. Companies have developed reduced-risk pesticides that can be integrated into an IPM system, he says. For instance, the pesticides of the future will be targeted at biological processes that are unique to the pest species and will not affect beneficial insects. —JANET PELLEY
Surprising human health-perchlorate link A statistically significant association has been found between ammonium perchlorate contamination of drinking water from the Colorado River and abnormal thyroid activity in Arizona newborns, marking the first time an associative link has been demonstrated between a human health effect and a potential low-level environmental exposure. Ammonium perchlorate is a component of rocket fuel and has been manufactured or used in almost every state. It was first discovered in drinking water in late 1996 in the western United States, spurring an interagency task force to look into potential health implications (Environ. Sci. Technol. 1998, 3 (5), 210A). Before that time, perchlorate could not be detected much below 400 ppb. Now that it can be detected at levels as low as 4 ppb, "it's showing up wherever people or agencies are taking the initiative to search for it in areas of potential release," which include the states along the eastern seaboard from New York to West Virginia, into the Midwest and Southwest, as well as in the Pacific Southwest,
Newborns studied in Yuma, AZ, had high TSH values, indicating perchlorate exposure, which may have come from drinking water drawn from the Colorado River.
says Kevin Mayer, U.S. EPA's Region 9 perchlorate coordinator. Perchlorate has long been known to have an effect on the thyroid gland. High doses of potassium perchlorate were used to treat hyperthyroidism in the 1950s and 1960s until its therapeutic use was linked with aplastic anemia. In finding the link between a human health effect and environmental contamination, a new study, which was presented at the annual American Water Works
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Association (AWWA) meeting in Denver, in June, looks at just two cities, Yuma and Flagstaff, AZ. The city choice is critical because of the difficulty in comparing urban water supply systems, which typically get their water from a number of sources. In this case, Yuma has a welldefined source, obtaining 100% of its drinking water from the Colorado River, whereas Flagstaff gets its drinking water from a variety of sources other than the Colo-
Goverment Watch rado River. Ammonium perchlorate levels in Yuma's drinking water range from 5 to 6 ppb, within EPA's current reference dose of 4-18 ppb for drinking water. No detectable levels of ammonium perchlorate have been observed in Flagstaff's drinking water. After pinning down these two populations for comparison, Ross Brechner, chief of epidemiology and statistics at the Arizona Department of Health Services and lead author of the study, turned to a database containing information on 365,000 newborn children in Arizona collected from October 1994 to December 1997. He was especially interested in values measured for the thyroid stimulating hormone (TSH) because perchlorate is known to raise the TSH value. Because perchlorate crosses the placenta, and the TSH does not, "this means that any elevated levels of TSH found in the baby is produced by the baby, not the mother," Brechner says. Brechner ultimately considered 1099 newborns in Yuma and 443 in Flagstaff. To make sure that one or two high numbers would not skew the whole analysis, Brechner used median values rather than averages. Yuma showed a significantly higher median TSH value in the range of 19-20 microunits/ liter, whereas the median TSH value in Flagstaff newborns was 12-13. "In other words, newborns whose mothers [probably] drank ammonium perchlorate-contaminated water versus those who didn't were significantly more likely to have an elevated TSH," Brechner says. Moreover, birth weights were found to be higher in Yuma than in Flagstaff, a factor that normally tends to lower the TSH value. During his database analysis, Brechner found out that hospitals did not always get a chance to measure the TSH value on the same day because of today's typically short hospital stays. Hence, some newborns were measured within 24 hours of birth, some after 48 hours, some after 72 hours, and some not until weeks later. Because the TSH spikes within the first 30-40 minutes after birth and
then drops rapidly, Brechner had to adjust for that, as well as ethnicity using a three-way analysis of variance and data transformation procedure. Even so, a statistically significant difference between the two populations was still observed. Brechner points out a number of weaknesses with the data— namely mat the percentage of people drinking bottled water is unknown; nobody has ever measured botded water for ammonium perchlorate; no individual measurements of home tap water, adults, or children were taken; and nobody knows how many people might have just moved into the area from another town. In addition, "We don't know with any certainty the clinical significance of TSH elevation in newborns, but on the other hand, it's not safe to assume mat elevated TSH values are harmless," Brechner says. Although he emphasizes that this is merely an observation of a statistical correlation, not cause and effect, "it's very unusual to find any connection between the environment and humans." To tell people not to drink the water based on this study alone, however, is a little premature, he adds. Frank Blaha of AWWA's Research Foundation (AWWARF) agrees. "I think [this study] could be fairly important in terms of establishing some of these low concentration impacts due to perchlorate," but more needs to be done because getting rid of perchlorate in drinking water will cost a lot of money. Ammonium perchlorate can be removed from drinking water through treatment methods such as membrane removal, ion exchange, and biotreatment, but these treatments are proprietary and thus very expensive, says AWWARF's Traci Case. Further research to make such treatment more economical is under way. Earlier this year, the U.S. EPA finalized a perchlorate monitoring requirement meaning that large public water supply systems and a substantial subset of smaller public water supply systems will have to monitor for perchlorate levels. —KRIS CHRISTEN
harmful substances for lead, mercury, cadmium, hexavalent chromium, and the flame retardants polybrominated biphenyl and polybrominated diphenyl ether by 2008. The Council of Ministers and the European Parliament are not expected to approve these controversial proposals anytime soon. In the United States, at least one state has passed a voluntary recycling initiative, but no federal mandate is in place. To view the directives on the Web, go to http://europa. eu.int/comm/environment/ docum/00347_en.pdf.
Cleaner waters? More than three years in the making, a directive aiming to unify surface and groundwater protection across the European Union (EU) was agreed to in June by the European Parliament and the EU's Council of Ministers. Once the directive is formally adopted, which was expected this month, member states will be required to clean up their waters to meet or maintain certain ecological and chemical standards by 2015. Key provisions include a river basin approach to water management with the designation of specific protection zones, such as areas intended for swimming or drinking water withdrawals, as well as the introduction of water pricing. Member states will be required to charge prices reflecting the true costs of water management activities. In addition, certain pollutants deemed to pose unacceptable risks to aquatic environments will be targeted for a ban or gradual phaseout. Pollutant limitations under this directive are likely to have little effect on agriculture, however. Pressure on agriculture may come from limitations on the overextraction of water.
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