window dressing." However, Starr also took the opportunity to criticize EPA enforcement for being "uncoordinated, unfair, inconsistent, and focused on small issues at the expense of larger ones." Defending proposed cuts to EPA enforcement of 25% or more, Keith Cole, a counsel to Sen. Christopher (Kit) Bond (R-Mo.), chair of the Senate appropriations subcommittee that controls EPA funding, said EPAs role has increasingly been taken over by states, a trend Congress would like to continue. He said 83% of enforcement actions are currently done by states, and he noted that environmentally related spending by states has grown from zero 25 years ago to $9.3 billion in 1991. With states running more and more environmental programs, Cole asked, "Why should EPAs enforcement budget keep rising?" He predicted that in the years ahead, Congress will increasingly shift more environmental responsibility to states. Starr countered that front-line state prosecutors frequently have difficulty bringing enforcement actions against politically connected environmental offenders. "The states need EPA," he said. —JEFF JOHNSON
Clinton releases "thematic" budget The Clinton administration issued a "thematic overview" of its fiscal year 1997 budget priorities on Feb. 5. The quietly released overview stood in sharp contrast to the 2000-page document that normally is released each year to much fanfare and discussion. The 20-page overview held few environmental details, other than a priority for enforcement and Superfund, more funds for EPAs operating program, establishment of a tax incentive program for brownfield cleanups, more authority for state-run water programs, and increases for research on global climate change and ozone depletion. Noting "uncertainty over 1996 appropriations," the president said he anticipated transmitting a detailed budget by March 18.
NEWS SCIENCE Atrazine not an ecological risk, study says Despite its widespread presence in U.S. surface waters, atrazine, one of the most widely used agricultural herbicides, does not pose a risk to the aquatic environment, according to a recently published ecological risk assessment. The assessment, funded by the principal atrazine manufacturer, CibaGeigy, followed current best-practice recommendations and is being widely praised as a model assessment. But despite the rigor of the new study, some researchers believe it does not completely clear atrazine of possible ecological harm. "This new risk assessment is well done," said Anthony Maciorowski, chief of the ecological effects branch in EPAs Office of Pesticides. "But ecological risk assessment is still evolving. Other people would come to other conclusions." Although ecological risk assessment is an emerging field, EPA is backing it as the best means of integrating scientific information with decision making. The atrazine study is one of the first examples of an ecological risk assessment intended to influence such decision making. Recent research on the ecological effects of atrazine and the other triazine herbicides has been stimulated by an EPA "special review" started in 1994 and scheduled to produce findings at the end of this year. The review is EPAs procedure for determining whether a chemical may pose unreasonable risks to people or the environment. The determination is based on a risk-benefit analysis
and can result in a decision to cancel, restrict, or continue chemical uses. Human health issues triggered the review, but ecological effects also concern the agency, according to EPA review manager Joe Bailey. "When we initiated the review, we felt that there might be an ecological effect, but at the time we could make a stronger case for human health concerns," he said. The review process will attempt to weigh and balance human and ecological risks. The atrazine risk assessment was performed by a panel of scientists established by the Institute of Wildlife Toxicology, Clemson University (North Carolina) and headed by Keith Solomon, director of the Centre for Toxicology, University of Guelph, Ontario {Environ. Toxicol. Chem. 1996, 15, 31). Atrazine kills weeds in corn fields by inhibiting photosynthesis. In surface water, the herbicide also affects aquatic plants. Determining the scope and significance of this effect is the bottom line for the risk assessment. The risk assessment tested three hypotheses: (1) Atrazine may cause temporary, reversible reductions in plant productivity, and long, repeated exposure could reduce total biomass. (2) The herbicide could damage the ecosystem community structure and reduce the ability of the habitat to sustain other organisms such as fish. (3) Direct effects of the herbicide on aquatic plants may result in adverse indirect ef-
Each year, 80 million pounds of atrazine are spread on U.S. crops, particularly corn.
1 1 0 A • VOL. 30, NO. 3, 1996 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS
fects on survival, growth, or reproduction of animals. The study concluded that all these hypotheses were unlikely. In the study, exposure, in the form of probabilistic concentration distributions, was compared with toxicity, in the form of sensitivity distributions, for a wide range of organisms. The degree of overlap of the exposure curves with the effects curves was used to estimate the risk to the aquatic ecosystem. The analysis showed that although conditions in most rivers, lakes, and streams did not combine to present risk to the aquatic ecosystem, sites such as small reservoirs in areas of intense atrazine use might present a risk and could be the focus of site-specific mitigation. "We knew that atrazine affects plants, but it does not directly affect fish," Solomon said. "So we needed to find out if any of the plants were 'keystone' species, crucial for the ecosystem to function." Algae and other plants provide the main source of oxygen for midwestern streams and rivers, so the productivity of these plants affects other organisms such as game fish. But research by others on the effects of atrazine in artificial aquatic ecosystems, or meso-
cosms and microcosms, showed that when sensitive plant species die off, other plants take meir place so there is no negative impact on the overall system, Solomon said. Although he acknowledges the methodological quality of the new study, Steven Mercurio, a toxicologist at Mankato State University (Minnesota) offered another view. Mercurio, who conducted a study on atrazine for EPA last year, suggests that in spring and early summer characteristically high atrazine loads could significantly inhibit algal growth at its crucial start and significantly decrease the oxygen content of midwestern streams and rivers. Mercurio contends that mesocosm studies present a different
picture of atrazine's effects on plants, with some indications that dissolved oxygen decreased at atrazine concentrations lower than those experienced in midwestern water bodies in springand summer. The consequences of this effect (lower dissolved oxygen and higher nutrient levels) "looks the same as the effect of fertilizer runoff, so it may not be readily apparent," he said. The discussion of the assessment of the ecological effects of atrazine in surface waters is likely to grow as the EPA review comes to a close. Atrazine's ecological risk will be the subject of a symposium at the American Chemical Society annual meeting in New Orleans this month. —REBECCA RENNER
Accident, ecological analyses hit in incinerator risk assessment Accident and ecosystem risk analyses were criticized by a peer review panel that examined EPA's draft risk assessment for Waste Technologies Industries (WTI) hazardous waste incinerator in East Liverpool, Ohio. The $1 million, 3300-page report is considered the most detailed site-
RESEARCH EPA experiments lost in federal shutdown Numerous toxicological studies dealing with dioxin, particulates, and other pollutants were disrupted when the government shut down in December and January, and many studies will take more than a year to repeat, according to EPA Office of Research and Development (ORD) officials. Hardest hit were toxicological studies involving dioxin, endocrine disrupters, and PCB exposure. These were mostly animal studies that required data collection at developmental or life-cycle stages that occurred while ORD was shut down, said Deputy Assistant Administrator Joe Alexander. He estimated the costs of the lost experiments to be between $5 million and $10 million. Several studies must start over, Alexander said. Two one-year projects, a dioxin dose-response study and a one-year polychlorinated biphenyls (PCB) exposure study, conducted at EPA's Research Triangle Park, N.C., laboratory, must be repeated because data collection was missed at a key point in the animals' life-cycles. A study in the Duluth, Minn., lab to determine baseline endocrine functions using brook trout was lost, and researchers must wait a almost a year to start again because of the trout's annual mating habits. Toxicology was not the only area hit. A field monitoring study of pollutant air transport in winter must wait until next winter to begin. At the Cincinnati, Ohio, lab, several long-term studies of drinking-water treatment technologies for disinfection byproducts and Cryptosporidium were delayed, Alexander said. —DANIEL SHANNON
specific risk assessment ever conducted and a benchmark of how such assessment should be done in the future. EPA's assessment grew from years of community concern about the incinerator. The draft assessment is particularly important because the incinerator is in a residential area. Overall, the draft found the human risk from the incinerator to be within acceptable levels [ES&T, Jan. 1996, 14A). The 19-member peer review panel, which met Jan. 11, was generally supportive of the draft with the exception of the accident and ecological sections. According to panel member Halstead Harrison, more adequate accidental risk data are needed in two areas. Harrison, an associate professor in the Department of Atmospheric Sciences, University of Washington, said the report did not adequately consider potential accidents involving pressurized releases of volatile materials from the facility's tank farm or transportation of waste to the facility. Harrison also said EPA should compare accident records from similar facilities, especially an identical incinerator in Biebesheim, Germany, which is owned and operated by Von Roll, WTTs owner. In an interview, Harrison said,
VOL. 30, NO. 3, 1996 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 1 1 1 A
