Environmental News Action on Gulf hypoxic zone moves ahead down a numerical goal," says Jim The largest environmental restora2010, or implement a descriptive Porterfield of the American Farm tion effort in the United States took goal instead of a numeric one. In Bureau Federation, a farm lobby a big step forward in July with the addition, the plan describes how group. Tremendous uncertainties publication of a draft action plan die task force partners can volunin the data mean tiiat some of the to curb nutrient pollution in the tarily reduce nitrogen loading to proposed strategies may not be Mississippi River and the Gulf of die Mississippi River by impleeffective, and farmers might be Mexico. The 31-state effort aims to menting best management pracpressured with regulatory meacut the nitrogen pollution that tices on farms, restoring wetiands sures if the goal is not met, he feeds a "dead zone" of low oxygen, and riparian buffers to absorb nisays. roughly the size of New Jersev that forms every sumBut others find numeric mer off the Louisiana coast. goals essential to the plan's Total nitrogen inputs and yields But controversy over selectsuccess. Cynthia Sarthou, from various subbasins ing a nitrogen reduction executive director of the The corn belt states of the upper Midwest, where goal could scuttle the efGulf Restoration Network, high inputs of fertilizer are flushed into the Mississippi forts a nonprofit environmental River by heavy rainfall, contribute most of the soluble organization, says, "a nuThe draft plan, pubnitrate that feeds the oxygen-starved dead zone in meric goal is necessary lished in the Federal Registhe Gulf of Mexico. to set a baseline, track ter (2000, 65 (133), 42,690progress, and measure suc42,697), is the product of a cess." Watersheds across the state, federal, and tribal globe, including the Chesatask force formed by the peake Bay and parts of the 1998 Harmful Algal Bloom Baltic Sea region have sucAct to tackle the challenge cessfully set numeric nutriof the Gulf dead zone. With ent reduction goals and the exception of 1998 and pursued voluntary strategies 2000 (see box), the oxygenthat would have been unstarved water has each year likely to move forward based doubled in size since it was on just a qualitative goal first measured in 1985. This adds Don Pryor of the Nahypoxic area forms when tional Oceanic and Atmothe fresh water of the Misspheric Administration sissippi stratifies the denser saltv water of the Many researchers say Gulf and deDosits nutrients that because the Mississippi that drive als?al growth The watershed is such an enordecaying aleae strip the wamous and complex ecosysters
of oxveen and QiifFnrnte marine animals that cannot On die basis of findings published in die Integrated Assessment of Hypoxia a 3CL Ul s i x relJUll-O C U I l U u c l c U LfV LX1C VV111LC JL {UUbC V-jUill —
Source: U.S. Geological Survey.
l I l l l l t ? C o i l J_iIlVllUIllIlCllL cillLl
i>iatural rvesources ycni'iron. Sci. TechnoL iy9o, 4 (10), 396A-397A) the plan backs ott from the assessment s conclusion that a 40 /o cut in nitrogen loading to the Mississippi is necessary to make a dent in die dead zone. Instead, the draft plan lays out three alternative options—namely, reduce nitrogen loadings to the Gulf 20-40% by 2010, shrink die size of the dead zone to 5000 square kilometers by
trogen, and reducing discharges from sewage treatment plants. The assessment's finding that fertilizer applied to farmland in the Mississippi River watershed accounts for 68% of the nitrate loading to the Gulf has put the spotlight on the agricultural community, which has long opposed a numeric goal for nitrogen reduction. "The science isn't there to nail
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tem, a 20% cut in nitrogen loading would be hard to distinguish from random fluctuations in the size of the dead zone. "With a cut of 40-50%, you may begin to see an effect on the dead zone " says Bill Mitsch, a professor of natural resources and environmental science at Ohio State University The difficulty in linking reductions in nitrogen loss at the edge of a farmer's field to diminishment of die dead zone raises concerns about numerical goals because they could become a batdeground if people think they mean something, says Otto Doering, economics professor at Purdue University. "But if modest
Government Watch
Drought curbs this year's dead zone This summer's measurements of the low oxygen area off the Louisiana coast known as the dead zone recorded the smallest zone since the 1988 drought, according to Nancy Rabalais, a marine biologist at the Louisiana Universities Marine Consortium. Mapped at 4400 square kilometers, the zone is one-fifth the size of last year's record-breaking 20,000 square kilometers. The two components necessary for stripping the water of oxygen—high nutrient flow from the Mississippi River and a layer of fresh water overlying salty Gulf of Mexico water—were much less abundant this year, thanks to drought conditions in the Mississippi basin, Rabalais says. The drought resulted in lower than average freshwater discharges from the Mississippi River and a lower flow of nutrients in March, April, and May, which contributed to this year's smaller hypoxic zone. —J.P.
targets help to get people around the table to cooperate, then they are healthy," he adds. If the plan sets an aggressive goal, there is a risk that key players in the states and agricultural industry will not sign on, admits Dennis Keeney, a senior fellow at the nonprofit Institute for Agriculture and Trade Policy in Minneapolis, MN. Of the four states with the highest nitrogen re-
leases, only Wisconsin and Minnesota are supportive of the plan's goals, while Iowa and Illinois are strenuously objecting to them. "If we can get a commitment from the agricultural industry to improve their practices, then come back and have another summit after a few years and strengthen the plan, we will eventually reach the goal," he says. JANET PELLEY
A new route for endocrine disrupters Most studies of endocrine disruption focus on interactions with hormone receptors, particularly the estrogen receptor. Now, Thomas Sanderson and colleagues from the Netherlands' University of Utrecht and scientists from Michigan State University (MSU) are demonstrating that endocrine disrupters can work in a different way by increasing production of aromatase, an enzyme that converts androgens to estrogens. Scientists have known that many other mechanisms of potential interference with endocrine function exist, and Sanderson and colleagues are among the first to prove that this happens. In in vitro experiments using the human H295R adrenocortical carcinoma cell line, the scientists found that 2-chloro-s-triazine herbicides, atrazine, simazine, and propazine dose-dependently induce aromatase activity. At a 30-pM concentration, an appar-
ent maximum induction of about 2- to 2.5-fold was observed after the cells were exposed to the triazines for 24 hours (see figure). These cells, which are like undifferentiated human fetal adrenal cells, can produce a range of steroid hormones. "This is the first documented case, to my knowledge, of aromatase enzyme disruption and a switch from androgen to estrogen," says Lynn Goldman, former chair of the U.S. EPA's Endocrine Disrupters Screening and Testing Advisory Committee (EDSTAC), which is overseeing the development of methods to evaluate chemicals for endocrine disruption. Sanderson and co-worker's results are in agreement with environmental toxicity studies. For example, Andrew Crain and coworkers at the University of Florida-Gainesville found that atrazine induced aromatase activ-
EPA's technology-based approach stands in contrast to California's Department of Agriculture standards, proposed in September, which are designed to ensure that heavy metals do not pose a risk to human health or the environment California's risk-based standards would allow higher levels of metals in fertilizers than technology-based standards, EPA officials say. But the Fertilizer Institute, an industry group supports risk-based standards because they are healthbased and reasonable for the industry to meet Environmental ciroups say California's standards will increase heaw metal levels in farm fields
EU harmonizes emissions monitoring A European Pollutant Emission Register (EPER), similar to the U.S. Toxics Release Inventory (TRI), is expected to enhance government monitoring of toxic emissions across the European Union (EU). The European Commission (EC) adopted plans for the register under the 1996 Integrated Pollution Prevention and Control directive in late July. T fie TRI covers more uian 600 toxic compounds, whereas fcrfcn wtii cover only 50 pollutants—-including greenhouse gases, metals, and organic and inorganic compounds, according to the EC. Contained in the EPER list, however, are a greater number of substance groups than in the TRI, which targets individual chemical species. Like the TRI, EPER's aim is public accessibility, but also emissions monitoring by governments, with governments reporting emissions directly to the EC. Most EU member states already have emissions inventories, but some are weaker than others, and they rely on different measurement methods, making communitywide comparisons difficult {Environ. Sci Technol!.999,33 (3), 61A-62A)
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