Environmental t News Arsenic in Katrina’s wood debris
als need to be treated differently in future disaster management plans,” says Tim Townsend of the University of Florida, a coauthor of urricane Katrina left behind “If you go into Lowe’s or Home the new research. Separating treatan estimated 55 million cuDepot today, you can’t buy CCAed lumber from the waste stream bic meters (m3) of tangled treated wood anymore,” says John after a natural disaster would be debris in Louisiana and MissisSchert, director of the Hinkley very difficult, Townsend says, but sippi—enough to cover 150 footCenter for Solid and Hazardous decisions about which landfill faball fields piled 15 meters high. To Waste Management at the Unicilities are suitable to accept conadd to the disposal problem, much versity of Florida. “Meanwhile, we struction and debris waste could of the lumber in those piles be made ahead of time. The contains arsenic, a known team’s handheld scanning carcinogen. device also could prove useThe arsenic comes from ful in sorting treated lumchromated copper arsenate ber at recycling facilities to (CCA) treatments that were avoid improper reuse—for applied to wood to protect example, as shredded mulch it against termites and dethat could leach arsenic into cay, two big problems in the backyard soil. steamy southeastern U.S. The new research also that made the pesticide very provides much-needed inpopular until recently. To formation that can be used sort the good wood from the to understand the fate of bad, a team of researchers CCA on a low-lying wet led by Helena Solo-Gabriele coastal plain, where the Brajesh Dubey of the University of Florida measures of the University of Miami likelihood of future groundarsenic concentrations in wood debris deposited by used handheld X-ray fluowater impacts remains unHurricane Katrina in New Orleans. rescence devices to make known, Schert adds. on-the-ground measurements of have huge volumes of wood out Almost 500,000 m3 of debris rearsenic in the New Orleans debris. there that will be in use for a long main in New Orleans, according The results are published in this istime, and we don’t know what to to estimates from the U.S. Army sue of ES&T (pp 1533–1536). do with it,” Schert says. Corps of Engineers, which is in The team sampled more than In two studies published previcharge of Katrina debris removal. 200 pieces of lumber at seven sites ously in ES&T (2005, 39, 155–163; The Corps has attempted to sepain New Orleans, including the 2006, 40, 994–999), Solo-Gabriele rate some materials, such as elechard-hit Ninth Ward neighborand colleagues showed that arsetronics, from the waste stream, hood, where piles of housing still nic in treated lumber leaches slowly but mixed construction debris is remain untouched. From their mea into soil. But discarded CCA-treated harder to sort. In addition, much surements in New Orleans, they wood is excluded by EPA as a hazof the debris cannot be legally reestimate that in total, Katrina deardous waste material under the moved because homeowners canbris in Mississippi and Louisiana Resource Conservation and Recovnot be located to give permission contained about 1740 metric tons ery Act, Solo-Gabriele notes, despite for demolition. of arsenic from treated wood. the fact that it fails EPA’s leaching In the meantime, tons of debris Arsenic-treated wood was tests designed to protect groundfrom Hurricane Katrina already banned in U.S. playground equipwater. “I would think it’s time to rehave ended up in unlined landment in 2001, and CCA manufacconsider that exclusion,” she says. fills, such as the new Chef Menteur turers and users agreed in 2002 to The researchers recommend that landfill in east New Orleans. The work with the U.S. EPA to take the CCA-treated debris from natural dilandfill lies in a wetland, and the pesticide out of residential use. sasters not be placed into unlined debris deposits have sparked an This led to the creation of arselandfills, where it could contamioutcry from neighbors concerned nic-free replacement chemicals, nate groundwater. about groundwater contamination which contain copper, for most “There needs to be a discusand ecosystem impacts. applications. sion about whether these materi—ERIKA ENGELHAUPT HELENA SOLO-GABRIELE
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© 2007 American Chemical Society
News Briefs
The risk of PBDEs in dust
Tom Webster
Scientists have long suspected that dust can play a major role in people’s uptake of polybrominated diphenyl ether (PBDE) flame retardants. New research published in this issue of ES&T (pp 1584–1589) is the first to definitively link the PBDE concentrations found in
Investigators captured dust containing PBDEs in people’s homes using a vacuum cleaner with this cellulose thimble inserted after the crevice tool.
people with the quantities of the persistent, bioaccumulative, and toxic (PBT) contaminants in dust from their homes. When considered in tandem with the U.S. EPA’s new assessments of PBDEs and data on the high concentrations of the contaminants in the dust of some U.S. homes, the findings suggest that children could be exposed to levels that put them at risk of developing neurological problems. Tom Webster and Nerissa Wu of Boston University’s School of Public Health led the international study, which involved collecting breast milk samples from 46 firsttime mothers in the Boston area. Although the researchers obtained dust samples from only 11 homes, they found statistically significant correlations between the levels of PBDEs in the dust from women’s homes and the concentrations of the contaminants in their milk. EPA released its long-awaited draft PBDE assessments for its Integrated Risk Information System
(IRIS) on December 22, 2006. EPA’s IRIS is an electronic database with information on the human health effects that may result from expo sure to chemicals found in the environment. The assessments calculate safe doses for human exposure to four PBDE compounds, or congeners. The lowest doses were 0.1 microgram per kilogram per day for two of the brominated diphenyl ether (BDE) compounds most commonly found in house dust, human blood, and breast milk: BDE–47 and BDE–99. The current safe dose for BDE–99 is 20 times higher, and BDE–47 was not previously assessed for safety. The levels of PBDEs reported in previous studies of house dust vary widely—as do the amounts of PBDEs that studies have shown can be taken up by North American citizens, who have the highest levels of PBDEs in the world. Heather Stapleton of Duke University, who is a pioneer in this research, says that people living in U.S. homes with the mean and median levels of PBDEs in their dust could be taking up amounts within an order of magnitude of the new IRIS reference doses. Of particular concern is the fact that “we are seeing such high levels in some homes,” Stapleton says. She calculates that children living in these homes could be “getting [PBDE] levels higher than the IRIS estimates.” The IRIS doses for BDE–47 and BDE–99 were based on research showing neurotoxic effects on developing animals. This suggests that growing children may be especially susceptible. Many scientists expressed surprise that EPA’s draft assessments were formulated on the basis of the doses of the PBDEs administered to the test animals, rather than the “comparable body burdens” ap-
Plastic harms mouse eggs
Bisphenol-A (BPA), a component of polycarbonate plastic that is found in many consumer products, is a potent scrambler of mouse egg chromosomes, according to a new study published in the Public Library of Science Genetics (2007, doi 10.1371/ journal.pgen.0030005). BPA is considered a “weak” estrogen and is found in human serum and amniotic fluid in the parts-per-billion range. Researchers exposed pregnant mice to environmentally relevant BPA doses of 20 micrograms per kilogram of body weight per day for 1 week while their daughters’ eggs were developing in the womb. The scientists found abnormal chromosomes in 40% of the daughters’ eggs, up from 1–2% normally observed. The findings show for the first time that early stages of egg development in the fetal ovary respond to estrogen.
Warmest year yet for U.S.
Last year’s average temperature made 2006 the warmest on record for the contiguous U.S., according to the National Oceanic and Atmospheric Administration (NOAA). The previous record-breaking year was 1998. The remarkable records partly stem from December temperatures, the warmest reported for a handful of New England states and Minnesota, which was more than 8 C above average for most of the month. Although the anomalously warm start to this year’s winter is attributable to an active El Niño season, NOAA acknowledges that greenhouse gases account for some portion of the overall warming trend. The past 9 years have made the list of the 25 warmest years in recorded history for the U.S.
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Environmentalt News proach now used for dioxins and PCBs. Because that approach compares the concentrations of PBT compounds in experimental animals with those found in people, it is more appropriate for compounds such as BDE–47, BDE–99, and BDE–153, which tend to have long half-lives in humans, on the order of years, Webster explains. What the new research does not show is where the PBDEs in the
dust are coming from. Webster’s questionnaire included detailed questions about potential sources of PBDEs, such as electronics, and furniture likely to contain foam padding. He says he and his colleagues were “surprised . . . that we couldn’t find any relationship based on what we know about how PBDEs are used in household products.” The paper also raises questions
about how much dust people take up. “In our review of the literature we found more than 100-fold difference in estimated dust ingestion,” points out Arnold Schecter, a professor of environmental sciences at the University of Texas School of Public Health. “Obviously, as the authors indicate, it is quite important for this key uncertainty to be resolved by further research.” —KELLYN S. BETTS
Dioxins and PCBs in rural areas distributions between cities and rural areas, appear to be spreading outward relatively quickly from urban centers. Cities, they conclude, seem to be creating plumes of the pollutants that can waft 160 kiloU.S. EPA
Several decades ago, industrial sites in the U.S., such as waste incinerators and paper pulp plants, spewed dioxins and related compounds into the atmosphere, polluting rural and urban areas alike. Years after controls resulted in reduced emissions from those sources, cities have stepped in to become the latest suppliers of the toxic contaminants in rural air, according to new research published in this issue of ES&T (pp 1537–1544). Following Clean Air Act requirements to control the releases of dioxins and PCBs from industrial sites, scientists predicted that levels of these contaminants would drop significantly. And they did. But by 1998, the contaminants leveled out in the atmosphere, according to measurements taken by the National Dioxin Air Monitoring Network (NDAMN). In the following years, until 2002, NDAMN recorded minimal changes in those levels. In the new ES&T research, David Cleverly of the U.S. EPA and his colleagues present 4.5 years of atmospheric measurements taken from 34 sites across the country, beginning in 1998. The team finds that the contaminants—polychlorinated dibenzo-p-dioxins (PCDDs), dioxin-like polychlorinated dibenzofurans (PCDFs), and coplanar PCBs—correlate with population density. Dioxins in particular, because of the similar
More than 30 sites across the U.S., including this one near Ozette Lake in Olympia National Park, track dioxins and PCBs in rural and urban air.
meters (km) away, into rural and remote regions, to 1000 km and beyond. “Higher amounts of PCBs observed in summer months are consistent with the theory that PCBs are volatilizing,” particularly from soils and plants, says Cleverly. “Dioxins are not so easily explained by their chemical–physical properties, but a fair amount of work points to a primary removal process: hydroxyl interaction or photochemical interactions in the atmosphere.” Previous research suggests that during cooler weather, humans burn more fossil fuels and
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engage in other activities that increase ambient levels of potentially cancer-causing chemicals. These chemicals eventually get sequestered in animal fats. The team confirmed a slight increase in dioxins in winter and a decrease in summer, particularly in northern latitudes. Cleverly and co-workers, however, suggest that winter conditions dampen the atmospheric chemical reactions of hydroxyl radicals with dioxin and photolysis of the dioxins, leaving more of the compounds intact in winter air. “It’s interesting that they report pretty stable patterns in rural and urban areas—even over seasons,” says Rainer Lohmann of the University of Rhode Island. The seasonal changes for dioxins are not significant, says Loh mann, who would like to see the data on the relative abundance of the different dioxins measured. “I doubt photolysis is as important as they think,” he adds. Because of air travel times, measurements would have to be made much farther away from urban centers in order to catch the hydroxyl chemistry, which can take days, he says. Therefore, vehicle traffic and other activities that change with the seasons cannot yet be ruled out as a source. Still, “this study was a huge effort, producing the first data set of its kind,” says Tom Harner, an Environment Canada researcher. We now have a high-resolution picture of how PCDD/F and coplanar-PCB concentrations vary with season and what the temporal trends are
pollutants. Lohmann notes that the yearly stability of dioxin and PCB concentrations shows that the U.S. may have reached the limits of emissions controls on manufacturing plants. “EPA has been very good at reducing emissions from big [manufacturing] plants, and they are now much more diffuse: general traffic, household burning of waste and wood,” and other “not very strong point sources,” he says. —NAOMI LUBICK
Antimony levels in bottled water
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The longer a bottle of water sits on a store shelf or in a household pantry, the higher the dose of antimony the person who drinks it will receive, new experiments show. In research published in this issue of ES&T (pp 1560–1563), scientists
The amount of antimony in bottled water varies from bottle to bottle.
find that the leached amounts can vary significantly, depending on the bottled water brand. Still, the amounts being measured are well below drinking-water standards. Last year, researchers at the University of Heidelberg Institute of Environmental Geochemistry (Germany) measured the abundance of antimony in 15 brands of Canadian bottled water and 48 European brands (Environ. Sci.
Technol. 2006, 40, 2500–2501). They reported concentrations of more than 100 times the average level of antimony in pristine groundwater, which is 2 parts per trillion. After letting the same bottles sit at room temperature for 6 months, the researchers found that average antimony concentrations increased by 19% in the Canadian bottled waters and by 90% in the European brands. Different samples of some of the same brands showed fairly consistent antimony leaching rates. In one case, however, a brand bottled in France but purchased in Hong Kong yielded significantly higher concentrations of antimony than the same brand purchased in Germany. Most of the waters tested were packaged in polyethylene terephthalate (PET) containers. “We really have no idea why these different PET bottles have different reactivities,” says Bill Shotyk, the lead author of the study. Antimony trioxide is used as a catalyst in the manufacture of PET. Shotyk suspects that elevated temperatures, different water pHs, and possibly exposure to sunlight could be playing a role in the varying leach rates. What’s clear, he says, is that water bottled in PET contains much more antimony than regular tap water. What isn’t clear are the implications for human health.
News Briefs EPA allows pesticides to be applied to water
Pesticides can now be sprayed or added directly into or near bodies of water to control mosquito larvae and weeds, without special permitting under the Clean Water Act. On November 21, the U.S. EPA finalized that decision, which affects both direct and airborne pesticide applications to water and provides monitoring and reporting protocols. While environmental groups have sued for more extensive permit requirements for all pesticides, pesticide manufacturers and industry groups filed lawsuits in December seeking to expand the rule. One aspect of the suits asks that the new EPA ruling be extended to usage beyond water and tree canopy applications to agricultural uses. CropLife America, one party to the lawsuits, argues that a different act, the Federal Insecticide, Fungicide, and Rodenticide Act, provides enough guidance to ensure that pesticides are safely applied in all situations.
State of the world: more and more urban
Cities are displacing rural areas as focal points of the world’s coming environmental problems and solutions, according to a new report by the Worldwatch Institute. The annual report, State of the World 2007: Our Urban Future, estimates that more than half of the world’s residents will live in cities by 2008, for the first time ever. Cities gain more than 60 million people every year, most of them in developing countries. Despite covering only 0.4% of the earth’s surface, urban areas generate the majority of the planet’s carbon emissions and are already straining global water supplies and natural resources, the report says. The report’s authors call for a greener urban future with more local food production, more efficient transportation, and less waste production.
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over several years, Harner says. The data can be used to test fate and transport models, particularly for the more volatile species that interact with hydroxyl radicals. And they will be useful for assessing the success of regulations by establishing a baseline for future comparison. They can also be used for future assessments under the Stockholm Convention of the UN Environment Programme, which lists PCBs and dioxins in the “dirty dozen” of global persistent organic
Environmentalt News “It’s an emerging contaminant, and one ought to take a closer look at it,” says Annette Johnson from the Swiss Federal Institute of Aquatic Science and Technology. Antimony is a suspected carcinogen, “but there’s no proof of this,” she cautions. Additionally, exposure through drinking water may not turn out to be the primary source, particularly in cities, because antimony is
used in such a wide range of products. “One of the most direct uptake possibilities is dust, where you have very elevated antimony levels because of brake-pad erosion,” Johnson notes. Mike Neal, chairman of the PET Health, Safety, and Environment Committee of Plastics Europe, stresses that antimony trioxide underwent extensive toxicological testing before its use was allowed
Climate change could offset ozone cleanup formation. But as temperatures climb, ozone formation is favored over PANs. Predicting future climate effects has not been straightforward, however. Global warming tends to increase water vapor, which deHARRIS COUNT Y PUBLIC HE ALTH AND ENVIRONMENTAL SERVICES
An emerging body of research shows that warming global temperatures can increase the production of smog-forming ozone, possibly by enough to overtake predicted improvements in air quality from cleaner technology. This new research is revealing that climate change affects groundlevel ozone via complex interactions of warming and increased production of natural smog-forming volatile organic compounds (VOCs), such as isoprene made by trees. Although the basic causeand-effect mechanisms have been understood for some time, only recently have models been able to incorporate emissions, climate, and chemical transport to make reliable global and regional predictions. Some of these new data were presented at the December 2006 American Geophysical Union (AGU) conference, and other results were published recently in the Journal of Geophysical Research. Atmospheric chemists have been studying the effects of meteorology on ozone for years, says Peter Adams of Carnegie Mellon University. “Their question wasn’t about climate change,” he says, but they did learn that temperature can shift chemical reactions in a direction that either favors or hinders ozone formation. At cooler temperatures, ozone precursors called nitrogen oxides (NOx) react to form peroxyacetyl nitrates (PANs) instead of catalyzing ozone
Signs such as this ozone alert in Houston, Texas, could become more common with future climate change.
stroys ozone in the atmosphere through chemical reactions. Yet, warmer temperatures also drive the reactions that form ozone and increase production by plants of ozone precursors. The balance between increased ozone production and destruction, especially at regional scales, has been difficult to quantify until recently. Adams and graduate students
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in food and beverage packaging. Moreover, in 2005, the European Food Safety Authority increased the migration limits of antimony from plastic materials into foodstuffs from 10 to 40 ppb. Questions still linger though over antimony’s potential carcinogenicity, which is why it was placed on a list for further study by the U.S. National Toxicology Program. —KRIS CHRISTEN
Pavan Racherla and John Dawson of Carnegie Mellon University tied together NASA’s global climate models with global- and regional-scale chemical transport models for ozone to understand the net effect of a changing climate. “Even though background ozone may decrease under future climate change, you can still have more frequent and intense ozone pollution episodes on short-term regional scales because of PAN chemistry and isoprene emissions,” Adams says. Their work was published December 16 in the Journal of Geophysical Research (2006, doi 10.1029/2005JD006939). The group looked at the eastern U.S., which has both high anthropogenic emissions and high natural emissions of VOCs from trees. “In more polluted areas, there are processes that are not captured if you only look at global changes,” Racherla says, noting that over the southeastern U.S. where isoprene emissions are highest, climate change alone can increase summertime ozone concentrations by 10 parts per billion (ppb). The U.S. EPA’s current ozone standard is 80 ppb. To understand the effects of climate change in the drier western U.S., Allison Steiner of the University of Michigan and collaborators at the University of California, Berkeley, are studying central California, where ozone and smog in some areas regularly exceed EPA attainment levels. Steiner modeled future ozone levels in combination with projected reductions
ent and future climates. She predicted that under future climate scenarios, emissions of natural VOCs, such as isoprene, and the secondary reactions of VOCs in the atmosphere will become more important. A regulatory focus on curbing tailpipe emissions may therefore not be adequate to suppress ozone production in central California, she says. Both research groups were funded through EPA’s Global Change Research Program in the first-ever round of funding to study the potential effects of climate change on air quality. The funding is focused on ozone and particulate matter, both of which are sensitive to climate. —ERIKA ENGELHAUPT
Debate over lead in air When the U.S. EPA raised the possibility of removing lead from the list of six “criteria” air pollutants it regulates, because ambient lead levels are no longer a problem in most parts of the country, the idea was widely ridiculed by environmental groups and a few key members of Congress as the action of an industry-friendly White House. Such a simplistic condemnation misses the point, according to experts, who say that delisting lead as a criteria pollutant fits with the letter of the Clean Air Act (CAA) but as a practical matter doesn’t protect public health. The option to delist lead was mentioned in a December 5, 2006, draft agency staff paper developed as part of a review of the criteria standard. The CAA requires EPA to review and, if needed, update the six criteria pollutants every 5 years, but the agency often misses these targets. The current criteria standard, 1.5 micrograms per cubic meter (μg/m3) of air averaged over a 3-month period, was set in 1978 when public-health officials thought that lead was much less
harmful. A partial EPA review in 1990 suggested that the standard could go as low as 0.5 μg/m3 averaged over one month, but the agency never revised the standard. The new leaders of two congressional committees that oversee EPA’s activities, Rep. Henry Waxman (D-CA), and Sen. Barbara Boxer (D-CA), immediately denounced the delisting option and cited lead’s well-known effects on the brain development of young children. The draft paper comes just months after a scientific summary by EPA advisers concluded that no safe human level for lead exposure exists. The summary, endorsed by EPA’s Clean Air Science Advisory Committee (CASAC), didn’t offer any regulatory options. Current levels of atmospheric lead in most parts of the country are very low, says Rogene Henderson, CASAC’s chairperson and a senior scientist at the Lovelace Respiratory Research Institute in Albuquerque, N.M. “Air is just not a major source of lead in most parts of the country,” she says. Yet public-health scientists familiar with the situation are di-
News Briefs Arsenic removal strategies debated
Policies and technologies aimed at cleaning surface water and groundwater of arsenic in geologically tainted regions, such as India and Bangladesh, have been relatively unsuccessful since the discovery of the problem in the mid-1980s, a group of researchers says. The best solution, they say, is not treatment but regular testing of deeply sunk tube wells to ascertain which ones are clean. A group of researchers from Bangladesh, Switzerland, the U.K., and the U.S. write in the December 15 issue of Science (2006, doi 10.1126/science.1133146) that current policies, particularly in Bangladesh, should shift to encourage use of deeper wells. Although four treatment technologies may come to market soon, past removal practices such as sand filtration provided “mixed” results, the authors note. Education and periodic monitoring, they suggest, will be most effective in keeping people from switching to unsafe sources.
San Francisco sued over “toxic toy” ban
A citywide ban on the sale of children’s products containing bisphenol-A and phthalates set industry lawyers in motion to sue San Francisco in federal court. The rule forbids the manufacture and sale of children’s products containing the chemicals, from dolls to rubber duckies. The San Francisco Chronicle reported that a city supervisor introduced amendments on January 23 that would limit the original law’s regulation of bisphenol-A to a list of products, based on laboratory tests. The American Chemistry Council and others representing bisphenol-A manufacturers agreed to hold off on one suit, while a separate suit still stands regarding the phthalate ban.
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in human-caused emissions of smog-forming NOx, VOCs, and carbon monoxide for the year 2050. She published the model results in the October issue of the Journal of Geophysical Research (2006, doi 10.1029/2005JD006935), showing increases of as much as 10 ppb in peak ozone events, amounting to a 3–10% change in the daily ozone maximum. “This is enough to push a moderate day into a severe-ozone-quality day,” she says, adding that it’s comparable to the amount by which ozone is expected to be reduced through emissions controls in that time frame. Steiner presented data at the AGU meeting in December on the contributions of different VOC sources to ozone levels under pres-
U.S. EPA
Environmentalt News Airborne lead concentration (µg/m3)
1.6 1.4 1.2
90% of sites have concentrations below this line.
1.0
1983–2002: 94% decrease 1993–2002: 57% decrease
0.8 0.6 Average 0.4
10% of sites have concentrations below this line.
0.2 0.0
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 Year
The figure above shows the trend in overall U.S. airborne lead concentrations for a subset of the EPA monitoring sites from 1983 through 2002.
vided. Some say that the “no safe level” conclusion of the CASAC review requires a new, much tighter criteria standard for lead. Then ambient levels should be compared with that new standard, and if warranted, EPA can declare victory over airborne lead emissions. Others support EPA’s delisting suggestion, saying the agency should focus on the high lead levels in the air around some industrial sites, such as lead smelters and battery recyclers. Currently lead is controlled under the CAA as a criteria pollutant and as a Hazardous Air Pollutant (HAP). Former CASAC chair Mort Lippmann, a New York University Medical Center professor of envi-
ronmental medicine, endorses the delisting of lead and the tightening of the HAPs emissions standard that would affect individual sources. “With lead long out of gasoline, it is now a classic point-source pollutant, and it should have a stringent emission standard,” he says. HAPs, or air toxics, are regulated on the basis of available technology and cost considerations, says Johns Hopkins epidemiologist Lynn Goldman, a former EPA assistant administrator. The CAA allows the HAP standards to be linked to health effects through a “residual risk assessment”, but EPA has moved very slowly on these assessments, so any suggestion that EPA would perform a residual risk
Unreliable water-quality forecasts at mines Hard-rock mining for ores such as gold and silver has left a poisonous legacy of acid drainage and toxic metal pollution in the U.S. that will cost taxpayers at least $20 billion to clean up. Part of the blame for this mess lies with premining forecasts of water quality, most of which are plagued with errors, according to a new report commissioned by Earthworks, an environmental group. A detailed study of 25 of the na
tion’s 183 large hard-rock mines reveals that 76% have violated U.S. EPA water-quality standards, despite predictions made from 1979 to 2003 that they would not, says Ann Maest, a hydrogeochemist at Stratus Consulting and the report’s coauthor. The broad review marks the first comprehensive comparison of predictions with actual impacts, and the results can be extrapolated to all of the nation’s large hard-rock mines, accord-
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assessment for lead is an empty promise, Goldman observes. At the same time, the national criteria standard for lead is tougher than the HAP, “because [criteria standards] are designed to protect the health of sensitive populations,” says Goldman. If EPA removes lead from the criteria list, protection from lead exposure also will be weakened, particularly for individuals living near point sources such as smelters and battery recycling plants, she says. EPA spokesperson John Millett agrees that lead emissions from smelters are a problem, and they are regulated as a HAP. The only primary lead smelter in the U.S. is in Herculaneum, Mo., about 30 miles south of St. Louis. Last year it emitted 25 tons of lead and met its HAP emissions limit, according to EPA. Yet Herculaneum is one of two areas of the country that regularly fails to meet federal criteria lead standards. In 2002, 28% of children in the town had blood lead levels higher than the Centers for Disease Control and Prevention’s level of concern. Maxine Lipeles, director of the Interdisciplinary Environmental Clinic at Washington University in St. Louis says that delisting lead as a criteria pollutant will worsen the situation in the town because the smelter would only have to meet the HAP rule. —REBECCA RENNER
ing to Comparison of Predicted and Actual Water Quality at Hardrock Mines and a companion report released on December 7, 2006. Levels of toxic heavy metals such as lead, mercury, and cadmium exceeded standards for groundwater and surface water at 63% of the mines, and levels of poisonous arsenic and cyanide overshot standards at more than half of the mines sampled. Impacts such as fish kills and contamination of drinking water used by humans and livestock have led to lawsuits at more than one-third of
of samples, Maest asserts. Detailed characterizations of a proposed mine’s mineral composition remain underutilized for predicting the behavior of mined materials. Leaching tests, which mix crushed rock with simulated rainwater to determine the rocks’ acid-generating capacity, should be run for 2 years, but frequently they run for only hours or weeks, she says. Mine EISs also tend to overestimate the effectiveness of mitigation measures, such as lining waste rock dumps with plastic or mixing acidic waste with acid-neutralizing rock, Maest says. However, some mining companies have learned from the mistakes of the past and are now using an acid drainage analysis similar to the one recommended in the Earthworks report, says Bill Williams, vice president of health, safety, environment, and construction for Rio Tinto and BHP Billiton’s Resolution Project copper mine in Arizona. The environmental analysis for the proposed Resolution mine is being critiqued by an expert review panel, Williams says. And the company is taking a pollution-prevention approach, he says. —JANET PELLEY
CO2 in the Supreme Court Lawyers representing the U.S. EPA have squared off against those from a coalition of 12 states in front of the U.S. Supreme Court, laying out their best argument to convince the justices of their answer to one simple question: does the Clean Air Act grant the U.S. EPA authority to devise national limits on CO2 emissions from cars? Both sides have a lot hanging on the court’s decision, which could mean either the beginning of mandatory greenhouse gas controls in the U.S. or a wait until Congress decides the matter. The case, Massachusetts v. EPA, argued before the Supreme Court on November 29, hinges on the
court’s interpretation of the Clean Air Act (CAA) provisions for automobiles. The law notes that an air pollutant from tailpipes can be regulated if it is found to harm health and welfare, the states say. It also contains a provision, in Section 302(h), which says harm to welfare includes effects on weather and climate. But Bush Administration officials assert that the CAA does not specifically name CO2 as an air pollutant, and therefore EPA can’t act to limit automobile emissions. Even if it had the authority, the federal government wouldn’t take the step to control CO2, EPA adds. The issue came forward in 1998 when EPA,
News Briefs Taking aim at aviation emissions
As of 2012, all flights into and out of the EU will be covered by the EU’s greenhouse gas emissions trading system, under a proposal laid out by the European Commission (EC) in late December. The system is the centerpiece of EU efforts to meet emissions reduction targets agreed to under the Kyoto Protocol on climate change. Including aviation is necessary, EC officials say, to account for the environmental costs of rapidly growing emissions from this sector, which are threatening to wipe out gains made by other sectors. To counter threats of legal action by the U.S., international carriers will be given an extra year to comply. To reduce overall emissions, airlines can take measures such as investing in more efficient aircraft, adding surface treatments to reduce drag, and minimizing the number of empty seats on planes for greatest efficiency. Air travel currently accounts for only about 3% of total greenhouse gas emissions in Europe, but these are expected to more than double by 2020 under a business-as-usual scenario. Since 1990, aviation emissions have increased 87%. With this measure, EC officials estimate annual CO2 savings of 46% or 183 million tons by 2020. The EC will set pollution limits based on average aviation emissions in 2004–2006, allocating credits to specific airlines. The airlines will then be able to buy, sell, or bank the credits within the aviation sector to meet their required reductions. The legislation now heads to the European Parliament and Council of Ministers for adoption, which typically takes 1–2 years. The proposal is available at www.ec.europa.eu/environment/ climat/aviation_en.htm.
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the mines, Maest says. Some mines could produce acid drainage for thousands of years. Approximately 5000 miles of streams are affected by acid mine drainage from abandoned hard-rock mines, according to a 1996 General Accounting Office report, Maest says. Water pollution begins when mining exposes sulfide-containing rocks to oxygen, rainfall, and bacteria, which react to generate sulfuric acid. In addition to acidifying surface and groundwater, the sulfuric acid dissolves other minerals and releases toxic metals, Maest says. Mining companies must submit detailed environmental impact statements (EISs) to regulators before digging, says Kirk Nordstrom, a hydrogeochemist at the U.S. Geological Survey (USGS). Included in the EIS is a forecast of how the water quality will change. “We know enough about how rocks and minerals react with water to have a pretty good general idea of what the water quality is going to be like” at a mining site, he says. Good models have been around for 25 years, and after 1990 the kinetic geochemical leach tests really improved, says Maest. But studies for mining proposals rarely contain adequate numbers
Environmentalt News under the Clinton Administration, agreed that it can regulate CO2. In 2002, EPA reversed that position. The coalition of petitioners that filed the lawsuit—12 states, 3 cities, and 10 environmental groups—say that CO2 causes harm to individuals as well as to states affected by extreme weather events and sealevel rise. Yet not all 50 states support the petitioners: 10 states have sided with the Bush Administration. If the court sides with Massachusetts, the question would return to EPA, although all sides agree that the Bush Administration isn’t likely to change its view. Mandatory CO2 controls will most likely come from Congress. “We would agree that [Congress] is the right place for the issue to be resolved,” says Quentin Riegel, vice president for litigation and deputy general counsel at the National Association of Manufacturers. “There should be a clear decision by Congress, because ev-
eryone will be affected and everyone will pay in some sense.” The Democratic leadership of Congress “is much more interested in global warming than the last Congress,” says Judi Greenwald of the Pew Center for Global Climate Change, a nonprofit research group. Committee chairs are likely to start with “fact finding” about climate change, says David Doniger, a lawyer with the environmental group Natural Resources Defense Council. Those who favor greenhouse gas limits say that Congress will seriously consider the issue in 2–4 years, and many supporters assert that “Congress will pass a bill by 2010,” Greenwald says. The most immediate impact from a court that agrees with Massachusetts will likely be seen in a separate lawsuit, filed by automakers. The lawsuit challenges regulations finalized under a California law, referred to as the Pavley law
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(Environ. Sci. Technol. 2005, 39, 279A), that establishes CO2 limits on automobiles. The California standards are illegal because the CAA doesn’t allow the federal government to control greenhouse gases, the automakers say. Before California can put its standards into practice, EPA must approve the plan, and it has refused to do so. Eleven other states are poised to adopt these California standards. If the Supreme Court sides with Massachusetts, “the federal authority is clarified, and the argument of the California automakers would collapse,” Doniger predicts. Once the California case is settled, national requirements on CO2 could very well be in place, these lawyers say. To view a text of the November 29 oral arguments, go to www.supremecourtus.gov/oral_ arguments/argument_transcripts/ 05-1120-pdf. —CATHERINE M. COONEY
