with EPA's position on methylmercury the most stringent. It is unlikely that the group will easily reach agreement, according to several scientists who plan to attend the meeting. Last December, EPA published a long-awaited, comprehensive report on mercury which included a reference dose of 0.1 micrograms of methylmercury each day for each kilogram of an individual's body weight. This dose is about equal to 0.2 parts per million (ppm) methylmercury in fish, and it is 5 times lower m a n the ATSDR's draft recommendation published last November. EPA's stringent recommendations have been criticized for potentially discouraging people from eating fish and depriving them of important health benefits An analysis published in the December 1997 issue of Science noted that an adult woman of average weight who weekly consumes four ounces of commercial fish with average mercurv concentrations would be exDosed to mercurv levels more than double EPA's rpference rlose The Food and Drug Administration is currendy preparing to revise its regulations which use a maximum permissible level of 1 ppm methylmercury in fish or shellfish, according to Michael Bolger, chief of the contaminants
branch at FDA's Center for Food Safety and Applied Nutrition. FDA's existing level, which has regulatory force, is consistent with ATSDR. But this consistency is "fortuitous," said Bolger. FDA's review should be finished in 1999. The agencies' recommendations are all used to varying degrees by states in their developSeveral states are moving ahead with controls on merment of fish consumpcury emissions despite the lack of federal agreement tion advisories of sport on whether current mercury levels in fish are harmfish (ES&T, Jan 1, 1998, ful. (Courtesy Uniphoto, Inc.) p. 9A). States have reported an increase in mercury advisories from 27 in Many states are contemplating 1993 to 37 in 1997, and the total or have taken similar actions, and number of mercury advisories Minnesota is in the vanguard. The increased 86 percent over the state reduced annual mercury S3.H16 St) 3X1 from 899 to 1675 acemissions from 10,000 to 4200 cording to EPA figures. pounds from 1990 to 1995 through source reduction and In the northeastern United more stringent emissions conStates and Canada, average levels trols. Wisconsin is also studying of mercury in fish far exceed EPA's the factors that control mercury reference dose, equal to about bioavailability in an effort to re0.2 ppm and are close to the FDA duce exposure, according to maximum permissible level, Bruce Baker, deputy administraaccording to a report issued in tor for water. But many states February by the New England Govalso see a pressing need for federnors and Eastern Canadian Preeral action to curb mercury emismiers. In May, the group issued a sions Baker said "We continue to proposed action plan to curb rebe disappointed at the lack of gional mercury emissions, which movement on national controls" account for close to half of the he said REBECCA RENNER region's mercury air deposition.
American wins Japanese award for green chemistry In late July, Terry Collins, a professor of chemistry at Carnegie Mellon University in Pittsburgh, Pa., won Japan's Society of Pure and Applied Coordination Chemistry Award for 1997 for his work in green chemistry. It was the first time the society's annual award honored a technique that could reduce the environmental impacts of industrial chemistry. Collins has developed a new class of oxidation catalysts that activate hydrogen peroxide. The catalysts could have "an enormous environmental impact" by allowing hydrogen peroxide to be used as an alternative bleaching agent in laundry detergents, water treatment, the pulp and paper industry, according to Paul Anas-
tas, a chemist in EPA's Office of Pollution Prevention and Toxics. After a "major breakthrough" three years ago, Collins and his fellow researchers found a way to protect their catalyst from the "very, very reactive" form of hydrogen peroxide it was used to create so the reaction could go to completion. Though hydrogen peroxide has die thermodynamic ability to carry out most of the reactions carried out by chlorine-based oxidants, it does not work quickly enough, Collins explained. The catalysts overcome this problem by activating the hydrogen peroxide. Extremely small nanomolar quantities of the catalyst are required for the activation, and die
process works in a variety of water temperatures and pHs. Collins has been granted four patents for the catalyst, including applications in laundry and pulp and paper. Because its bleaching action is very selective, the catalyst could allow hydrogen peroxide to be used in the first stages of paper processing. The new bleaching technique could work with existing equipment, thereby saving manufacturers the expense of retooling their facilities. The catalyst has promise as a bleach in laundry detergents because the activated hydrogen peroxide is a good whitener and less likely than chlorine bleaches to cause clothing dyes to run. —KELLYN S. BETTS
OCT. 1, 1998 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 4 4 5 A
