Environmental▼News PERSPECTIVE sooner than required, with a very high rate of compliance and no litigation to hold up the progress,” acIn proposing pollutant trading as a United States, EPA estimates that cording to EPA officials. But the acid means to reduce mercury from these utilities emit 48 tons of merrain program targets sulfur dioxide coal-fired power plants, the U.S. cury annually. (SO2) emissions, and the water proEPA is contemplating an action that The controversy centers on EPA’s gram is geared to reducing nutrient its own water agency program exUtility Mercury Reductions Rule, and sediment loadings to waterpressly discourages—trading in perwhich lays out two approaches. ways, not hazardous pollutants like sistent bioaccumulative toxics. But One would require utilities to install mercury. this is only one of the reasons that currently available pollution con“If something were to go wrong the agency has been inundated trols known as maximum achiev[with SO2 or water trading], and with criticism since January, when able control technologies (MACTs). you got a temporary overloading of the proposal was issued. Scientists EPA estimates that this approach, if nutrients, it’s something that can are also questioning be cleaned up and the agency’s stated will eventually go aim to cut mercury away,” says Suzie as quickly as possiGreenhalgh, a senior ble with the trading associate at the World plan, because some Resources Institute. analyses show that “A bioaccumulative the trading plan toxin is a whole difwould be less effecferent story.” tive than the plan it Charles Driscoll, a supplants. professor of civil and Opponents of the environmental engiproposal voice conneering at Syracuse cerns about the University, has complan’s long time piled a decade’s worth frames for signifiof mercury research. cant cuts in airborne He points out that mercury levels, mercury has a short The levels of mercury in New Hampshire’s loon population decreased which in turn could residence time in the rapidly in recent years, a change that scientists attribute to policy and make water quality atmosphere, particuregulatory changes the state made to curb mercury emissions. goals difficult to larly the reactive achieve and leave toxic hotspots. implemented, would reduce mergaseous and particulate forms, which fall out fairly close to the Many experts argue that existing cury emissions 29% by 2008. The alsource. Once in area waterways, and emerging technologies can ternative approach, which is EPA’s this deposited mercury can transbring about steeper mercury restated preferred choice, would set a ductions more quickly. The speed mandatory, declining cap on total form into methylmercury, which with which mercury reductions can mercury emissions and allow utilibioaccumulates in fish and animal be achieved takes on added signifities to buy emission credits from tissues. cance in light of the growing body other utilities in order to comply A recent study of common of scientific research indicating with clean air rules. loons in southeastern New that mercury reductions today can EPA estimates that the marketHampshire by the Biodiversity translate into observable ecosysbased trading program would reResearch Institute (BRI) indicates tem improvements within a decade duce mercury emissions 70% by that these mercury deposition patrather than over generations, as 2018. But critics say this timeframe terns can result in biological previously thought. is too long and that existing and hotspots. “We found extremely high EPA’s own data show that nuemerging reduction technologies mercury levels in the biota in that merous waters nationwide are could achieve a 90% reduction more area,” which also happens to be impaired because of mercury conquickly under a MACT approach. populated by a number of municitamination, and 44 states currently EPA’s trading scheme, as well as pal incinerators, says David Evers, issue fish consumption advisories the agency’s 2003 water quality BRI’s executive director. At the same related to mercury. Atmospheric trading policy (Environ. Sci. Technol. time, he attributes the rapid decline deposition from global and national 2003, 37, 216A–223A), is based on in mercury levels observed in loons sources is thought to be behind the acid rain trading program of the over the past couple of years to polimuch of this contamination, with 1990 Clean Air Act amendments. cy and regulatory changes made by coal-burning power plants conThe acid rain programs “resulted in the state to curb emissions from tributing the largest portion. In the more reductions than required, municipal incinerators. JOHN WILSON
Mercury trading scheme raises concerns
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we’d expect the system to respond much more quickly” to any curbs on mercury emissions. Research in the Florida Everglades also suggests that reducing air emissions could rapidly decrease mercury concentrations in fish and wading birds—much more quickly than researchers thought ecosystems would respond to reduced loading—according to Tom Atkeson, a scientist with the Florida Department of Environmental Protection. “We started out thinking of this as an aquatic problem, but we learned that it was really driven by atmospheric processes,” he says. Atmospheric deposition of mercury dropped significantly in the late 1980s because of regulations on emissions from municipal solid waste incinerators and voluntary actions to remove mercury from household batteries. Mercury levels in fish and wildlife from the Everglades continued to rise, peaking in the mid 1990s. “Today, mercury concentrations are down by roughly 75% from that peak” as a result of the emission control policies, Atkeson notes. EPA officials, for their part, recognize that their mercury plan has its critics. “We’re eager to hear them,” says spokesperson John Millett. He admits that water hotspots could form in some areas as a result of a cap-and-trade program, but he maintains that monitoring should keep any problems in check. “It’s envisioned that we’re going to see some major overall improvements with the trading approach, but we’re not sure where. It may also be that some areas won’t improve, and again, we’re not sure where,” Millett notes. But right now, “We want to cut mercury as much as possible, and then with the monitoring information developed through the cap-and-trade program, we’ll be able to refine the approaches and reduce mercury in any problem areas that arise.” For more information on EPA’s mercury proposals, go to www.epa.gov/mercury. —KRIS CHRISTEN
News Briefs Gold industry targeted The production of a single 18-karat gold ring weighing less than an ounce generates at least 20 tons of mine waste, according to leaflets distributed in major U.S. cities in February. Two nonprofit groups, Earthworks/Mineral Policy Center and Oxfam America, handed out the literature as part of a campaign to raise awareness about the toll that gold mining takes on humans and the environment. The groups have also released a report, Dirty Metals: Mining, Communities, and the Environment, which points out that metals mining employs less than 0.1% of the global workforce but uses 7–10% of the world’s energy. For more information, go to www.nodirtygold.org.
Site licenses vs subscriptions Are library site licenses for accessing scientific journals a good deal for the academic community? Not necessarily, according to a recent report (Proc. Natl. Acad. U.S.A. 2004, 101, 897–902). “Whereas electronic distribution can dramatically reduce the costs of producing and disseminating scholarly work, it is not clear that the scientific community will reap any of the benefits,” wrote a duo of biology and economics professors. They used microeconomics and elementary statistical theory to analyze the costs and advantages of electronic access to journals among six disciplines, including ecology, atmospheric science, and physics. Institutional site licenses from professional societies and university presses are cost-effective, but universities would be better off choosing individual print subscriptions offered by for-profit publishing groups instead of their highly priceinflated site licenses, according to the professors’ findings.
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RHONDA SAUNDERS
Environmental groups, too, worry about hotspots. “Certain areas may not be cleaned up at all, or cleaned up very little, because some utilities would be able to buy emission credits as opposed to making actual cleanups,” says Frank O’Donnell, executive director of the Clean Air Trust. Representatives of electric power industry groups, for their part, voice cautious support of EPA’s cap-and-trade approach for bringing mercury emissions down. However, many state environmental officials had been banking on a MACT approach. In fact, both of EPA’s proposed approaches fall short of a goal adopted in August 2003 by state air, water, and solid waste management directors that advocated the “greatest reductions possible within the shortest timeframe,” says Marcia Willhite, chief of the Illinois EPA’s Bureau of Water. Scientific findings also make the case for quick action. Preliminary results from mercury pathway experiments in northeast Ontario in Canada suggest that mercury recently deposited from the atmosphere is more bioavailable than existing mercury. In the study, known as the Mercury Experiment To Assess Atmospheric Loading in Canada and the United States, or METAALICUS, researchers are trying to determine what happens to fish mercury concentrations when changes occur in the amount of atmospheric mercury deposition (Environ. Sci. Technol. 2001, 35, 229A–230A). By dosing a watershed with stable mercury isotopes, “We’re finding that the mercury we add to the lake surface is much more prone to become methylated in sediments than relic mercury,” says David Krabbenhoft, a research scientist with the U.S. Geological Survey who is involved with the study. “This is important because if the pools of mercury that exist in upland and wetland soils were very active, we could be in for a long delay in terms of how long a recovery might take. If it’s only the mercury that falls directly on the lake,
