Assessing the risk of estrogenic chemical mixtures - ACS Publications

mental health, researchers at .... States. At the American Chemical. Society meeting in March, for ex- ample, Myrto Petreas ..... Assessing the risk o...
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Mounting concern over brominated flame retardants n the wake of mounting fects. evidence that brominated Hale believes that the flame retardants pose risks penta-BDEs are getting into to both human and environU.S. sewage sludge from fragmental health, researchers at ments of polyurethane foam the Second International released from old chairs and Workshop on Brominated couches. After the foam is exFlame Retardants held posed to the environment, it May 14−16 in Stockholm, tends to break down and fragSweden, reported that high ment into dust that can be levels of brominated flame washed down sewers, he says. retardants may be commonly “It doesn’t take a lot of found in office dust and even polyurethane foam to contamDustcollected from the United Kingdom’sHousesof high-quality sewage sludge. inate a lot of sludge,” he adds. Parliamenthad 4500µg/kg ofBDE-209,a polybrominated diphenylether,a levelresearcherssayis“high”. That documentation is likely Because polyurethane foams to turn more than a few typically contain heads, given that the tested dust director of the Human Studies 10–30% penta-BDE, by weight, if came from European Parliament Division of the U.S. EPA’s National the flame retardants in a foam buildings and the sludge could be Health and Environmental Effects cushion weighing 1 kg get into a used to grow American vegetables. Research Laboratory. They can sewage treatment plant, they can Despite growing evidence that cause liver and neurodevelopmencontaminate 100,000 kg of sludge at brominated flame retardants are tal toxicity, disrupt hormone sys1000 µg/kg.” Hale says that he has bioaccumulating throughout the tems, and be sensitizers, she says. found brominated flame retardants world, flame retardants are currentIn the United States, penta-BDE in even the highest “EQ” quality ly much more of a concern in is used as a flame retardant with the sludges. Europe and Japan than in the polyurethane foam that serves as More investigation would be reUnited States. The penta brominatpadding in seat cushions of all quired to determine whether older ed diphenyl ether (penta-BDE) forkinds, according to Robert Hale of polyurethane foam was the source mulation will be banned in the the Virginia Institute of Marine Sciof the brominated flame retardants European Union (EU) in 2003 ence at the College of William and found in the office dust collected (Environ. Sci. Technol. 2000, 34 (9), Mary in Gloucester Point, VA. Hale from the European houses of 222−226), and at the Stockholm looked for penta-BDE and “pentaParliament, according to David conference Kjell Larsson, the like” compounds in sewage sludge Santillo, a research scientist with Swedish Minister of the Environfrom different types of treatment the University of Exeter’s Greenment, vowed to push for all bromiplants throughout the United States. peace Research Laboratories. But nated flame retardants to be Hale’s research has yet to be puball samples, which were analyzed in banned in the EU. The chemicals lished, but he told conference attenconjunction with the Netherlands possess a number of the characterdees that he found levels ranging Institute for Fisheries Research istics of persistent organic pollufrom 1100 to 2290 micro(RIVO), contained “significant levels tants, says Maged Younes of the grams/kilogram (µg/kg), which he of brominated flame retardants,” World Health Organization (WHO), characterized as being a 40-fold inSantillo says. The researchers found who called on researchers to collect crease over the levels generally more than 20 different chemicals more data on human exposure to found in European sludges and 10 associated with brominated flame the compounds. times higher than the highest levels retardants in the dust they collectThere is evidence that at least previously reported in either Europe ed with the aid of the cleaning some brominated flame retardants or Canada. He found lower levels of staffs in 13 different European govcan be persistent, bioaccumulative, deca-BDE, another popular formuernment buildings, Santillo says, and toxic to both vertebrates and lation that researchers are currently noting that deca-BDE was found in invertebrates, says Linda Birnbaum, investigating for potential health efthe highest concentrations. The

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Italian and U.K. parliaments had the highest overall levels of brominated flame retardants in their dust, he says. The Exeter findings, which have yet to be published, call into question whether ingestion may be the main source of exposure to brominated flame retardants, Santillo says. That is important because it is still unclear how these flame retardants are getting into people,

Birnbaum says. Recent studies show that although the concentrations of polybrominated diphenyl ethers (PBDEs) in Swedish women’s breast milk may have peaked, the amounts are rising in the United States. At the American Chemical Society meeting in March, for example, Myrto Petreas reported the highest levels of PBDEs found in the adipose tissue of any woman to date, an average of 85.7 nanograms

Trade ministers urged to consider sustainability issues trade policy as it relates to environmental and social policy,” noted Pierre Marc Johnson, senior counsel with Heenan Blaikie of Montreal, David Runnals of the International Institute for Sustainable Development, and Enrique Leff of the United Nations Environment Programme, co-chairs of the symposium on “Hemispheric Trade and Sustainability”, which was held in Quebec City immediately before the summit. In a statement presented to trade ministers attending the summit, they called for the creation of a high-level hemispheric group of experts on trade and sustainability, which would analyze draft FTAA texts and recommend changes designed to protect the environment and promote sustainable development. Environmental concerns raised with respect to a future FTAA agreement include downward harmonization of environmental regulations (setting the standards governing international trade on the basis of the least PHOTODISC

At the Quebec City Summit of the Americas this April, representatives of the 34 participating countries reiterated their commitment to reaching an agreement for a Free Trade Area of the Americas (FTAA) by 2005. They also confirmed their commitment to sustainable development and recognized the interdependency of these two goals. Still at issue, however, is the extent to which sustainability issues should be directly integrated into the ongoing FTAA negotiating process. The FTAA aims to eliminate investment and trade barriers on goods and services traded by member countries, thereby reducing prices for consumers and creating new markets for producers. The decision to create the FTAA by 2005 was initially agreed upon in December 1994 at the first summit of the Americas by the 34 democratically elected heads of state of the Western Hemisphere. “Until now, FTAA negotiations have been unable to address the contentious issue of

Government Watch Bush ups funds for brownfields The Bush administration awarded $38 million on April 20 to help 90 communities assess and clean up abandoned industrial land known as brownfields. The funds, part of the U.S. EPA’s Brownfields Economic Redevelopment Initiative, will go toward $7 million in local grants to evaluate 36 contaminated sites and provide $26 million in revolving loan funds for cleanups in 46 communities. An additional $5 million will be used to continue and expand brownfields assessment on existing sites, whose redevelopment is often complicated by environmental contamination. Since 1993, the brownfields program has provided over $162 million in grants to local and state governments, which have leveraged an additional $2.9 billion and created over 11,000 jobs. Find out more about the U.S. EPA’s Brownfields Economic Redevelopment Initiative on the Web at www.epa.gov/brownfields.

EU clears the air Particulate matter and ground level ozone have been targeted as “the air pollutants of greatest concern” under the Clean Air for Europe (CAFE) program adopted by the European Commission (EC) in May. A growing body of scientific evidence shows that even small concentrations of tiny dust particles emitted by combustion-related sources adversely affect human health. Likewise, ozone formed in the lower atmosphere by the reaction of pollutants such as nitrous Continued on Page 277A

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Mutiny in Alaska? Alaska’s Arctic National Wildlife Refuge (ANWR) should not be developed until the oil industry cleans up chronic problems with leaking and faulty safety shutoff valves, according to whistle-blowers at BP Exploration (Alaska) Inc. On April 13, these anonymous critics launched a Web site to air their concerns. Environmental critics agree that because the North Slope experiences more than 400 spills annually, it appears that government regulators and industry officials are turning a blind eye to equipment maintenance and spill prevention problems. The allegations couldn’t have come at a worse time for the oil industry, which is pushing Congress to pass an act allowing development of the refuge’s oil field. Staff cuts triggered by oil production declines since the early 1990s have undermined preventive maintenance programs, leading to more spills and the risk of a catastrophic accident that would “leave a half-mile-wide oil slick on the white snow all the way to ANWR,” the workers’ Web site says. Staff at some wells has been cut by 30% since 1990, the site notes. Leaky hydraulic valve systems are a widespread problem on the North Slope and indicate that the valves are potentially at risk for failure, says Robert Watkins, section manager in the Alaska Department of Environmental Conservation’s pipeline program. A March inspection of the safety valves at BP’s G Pad drilling platform revealed that 9 of 30 components failed to work properly, admits Dan Seamount, commissioner with Alaska’s Oil and Gas Conservation Commission. The commission has found safety valve failure rates exceeding 10% at 6 of BP’s 21 drilling platforms, he says. JANET PELLEY

PHOTODISC

restrictive national standards), the creation of pollution havens (regions attracting investors through a weakening of environmental regulation or enforcement), the potential conflict of FTAA provisions with multilateral environmental agreements, and the ability of governments to pass new environmental legislation in the face of investor protection provisions within the trade agreement. This last concern has grown over the past five years as a result of suits filed under Chapter 11 of the North American Free Trade Agreement (NAFTA), in which foreign companies have claimed compensation from host governments for losses resulting from new environmental legislation (Environ. Sci. Technol. 1999, 33 (19), 404A). Much of the resistance to inclusion of environmental issues in the context of trade negotiations comes from Latin American countries, notes Johnson. One reason is the fear that environmental provisions in the FTAA agreement would be used by the United States and Canada as barriers to Latin American products. Brazil has been the most outspoken advocate of keeping environmental initiatives on a separate track from trade negotiations. As President Fernando Henrique Cardoso stated in his address to summit delegates, “the fight for environmental protection is a crucial endeavor that should continue to deserve high priority on the international agenda at the appropriate forums, but this fight must not become a pretext for protectionist practices.” Johnson agrees that environmental measures in a trade agreement should not become a vehicle for protecting domestic industries. But, he adds, Mexico had the same reservations during negotiations for the NAFTA treaty, which included environmental provisions in the main text and also provided a mechanism for environmental cooperation through a side-agreement. “In the seven years under NAFTA, Mexico has never had reason to complain on this front,” Johnson notes. —DEBORAH SCHOEN

Do Roundup Ready soybeans require more herbicide? Industry and agricultural authorities denounce a recent report’s claim that Monsanto’s Roundup Ready (RR) soybeans require more herbicide than conventional soybeans. In his report, Charles Benbrook, director of the nonprofit Northwest Science and Environmental Policy Center, charges that there has been a “lack of rigor in analyzing herbicide [application] rates in Roundup Ready soybean systems.” RR soybeans are genetically modified to be resistant to the broad-spectrum herbicide active ingredient glyphosate (Roundup) that kills weeds. To support his contention, Benbrook commissioned the U.S. Department of Agriculture’s Economic

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Research Service to re-evaluate the raw data for 1998 soybean herbicide use in the United States, which is collected from farmers each fall. According to Benbrook’s report, Troubled Times Amid Commercial Success for Roundup Ready Soybeans, RR soybeans will receive 0.5 more pounds of herbicide per acre than conventional soybean crops and will lead to an additional 20 million pounds of herbicide applied during 2001. Harvey Glick, Lead Global Biotech Stewardship at Monsanto, Tony Anderson, president of the American Soybean Association, and Don Latham, a soybean farmer and immediate past chairman of the United Soybean Board, disagree with Benbrook and say that although total her-

bicide use has gone up in the past few years, it is attributed to a dramatic increase in the number of acres planted. According to Anderson, in 1996, U.S. farmers planted 1 million acres of biotech soybeans or 2% of total soy acreage, and in 2000, 40 million acres or 55%. Even with increased acreage, Glick states, “in reality, farmers have reduced the overall rate of herbicide used.” Leonard Gianessi, a senior research associate at the National Center for Food and Agricultural Policy, says that Benbrook’s calculations are mathematically correct, but there were no statistical parameters to complete the analysis and support the results. The numbers are “too close to call”, Gianessi says. Glick isn’t focused on the amounts of herbicide. “Herbicide reduction is not the reason why RR soybeans were developed, nor the primary reason that farmers purchase it,” Glick claims. The farmers confirm it. Latham has used the technology over the last few years and sees five major benefits: saving soil by reducing tillage, its ease on the environment, its safety, the flex-

Government Watch

ibility to rotate crops, and cost savings of $22.80/acre last year. Benbrook counters that herbicide resistance in weeds is a major concern because multiple applications of Roundup are “imposing selection pressure on the weed population to an extraordinary degree … and it is going to cut short the effective lifetime of this technology.” Glick says Benbrook’s claim is incorrect. He claims that glyphosate has a unique mode of action and has presented only two weeds that show resistance to Roundup in 30 years of use, whereas other herbicides used on conventional soybeans that have been around for 15 years already have 60 weeds showing resistance. Benbrook believes that glyphosate may also promote soybean disease. “Farmers would be the first to know. I haven’t heard of a single instance where RR soybeans have any more or less disease problems than conventional soybeans,” says Latham. Benbrook’s full report is available at www.biotech-info.net/ troubledtimes.html.—RACHEL PETKEWICH

oxides and volatile organic compounds with sunlight causes many of the same health effects as particulates, and it attacks vegetation, forests, and buildings. With many of the EC’s existing air quality directives coming up for revision by 2004, CAFE is expected to culminate in an integrated strategy for combating air pollution. Additionally, environmental pollution’s impacts on human health represent one of the four areas highlighted under the sixth European environmental action plan (Environ. Sci. Technol. 2001,35 (7), 139A–140A) and is the first to be addressed by the EC. CAFE is also expected to address remaining air pollution problems related to acidification, eutrophication, and damage to buildings, as well as serve as a vehicle for monitoring emerging problems.

Massachusetts limits CO2

Researchers in Europe have found further evidence that the potencies of chemical mixtures are additive, provided the substances act on a specific endpoint via a similar mechanism. The results could help regulators determine when to set chemical-specific standards to protect the environment and when such an approach won’t work. In the June 15 ES&T issue (Environ. Sci. Technol. 2001, 35 (12), 2476–2481), Karen Thorpe and coworkers at the University of Exeter, AstraZeneca’s Brixham Environmental Laboratory, the Environment Agency’s National Centre for Ecotoxicology and Hazardous Substances, and Brunel University, all in the United Kingdom, and the University of Bremen, Germany,

BRIXHAM ENVIRONMENTAL LAB.

Assessing the risk of estrogenic chemical mixtures

Researchersinvestigate the in vivo potencyofestrogenic chemicalmixturesin juvenile rainbow trout.

investigate the in vivo biological potency of three estrogenic chemicals—estradiol-17β, 4-tertnonylphenol, and methoxychlor— both individually and as binary mixtures, using vitellogenin induction in juvenile rainbow trout as the endpoint. Only female fish are ex-

Massachusetts is the first state in the United States to regulate the reduction of CO2 emissions from electric power plants. The state’s Department of Environmental Protection is requiring plants to reduce their emissions of NOx and SO2 by 50% and up to 75%, respectively, by 2008. Technologies to cut mercury emissions are under review, and final mercury reductions will be set by June 2003. Officials in the Massachusetts Department of Waste Prevention and Evaluation believe that state sources should begin to reduce their emissions now to address global climate change concerns, and they support fuel efficiency as the best way to reduce mobile CO2 emissions. Companies operating the six targeted plants must immediately cap CO2 emissions and reduce those emissions by 10% by Oct. 1, 2006, under standard operations, or by Oct. 1, 2008, if they choose to Continued on Page 279A

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Other groups of chemicals also act via similar mechanisms, such as steroids or alkylphenolethoxylates. “We’ve developed a standard based on alkylphenolethoxylate chain lengths, which works very well,” says Geoff Brighty of the U.K. Environment Agency. “The problem

comes when you’ve got dissimilar substances,” he says. “It’s well worth doing the fundamental science to understand the strengths and weaknesses of how we are currently managing chemicals and their discharge into the environment.” —BRITT ERICKSON

A fern with an affinity for arsenic At an abandoned wood preservation site heavily contaminated with chromated copper arsenate in central Florida, scientists have discovered the first plant known to soak up large amounts of arsenic from the soil. Pteris vittata, or the common brake fern, accumulates the toxic element in its stems and fronds at concentrations greater than those found in the soils in which it grows, yielding bioconcentration factors as high as 193. “The brake fern not only tolerates arsenic, it loves it,” says Lena Ma, a chemist at the University of Florida–Gainesville and lead investigator. So much so that in greenhouse experiments Ma’s group found the plant doubled its biomass when soils were spiked with soluble arsenic. Moreover, the fern extracts the arsenic quickly and efficiently. An analysis of ferns growing in soils spiked with 1500 parts per million (ppm) of arsenic found that concentrations of the element in the fronds increased from 29.4 ppm to 15,861 ppm in just two weeks, according to results published in Nature (2001, 409, 579). In the same period, ferns growing in soil containing only 6 ppm of arsenic accumulated 755 ppm of arsenic, a 126-fold enrichment. After six weeks, the arsenic constitutes a whopping 2% of the fern’s weight, Ma says. “Never before have we seen an arsenic accumulating plant that even had a bioaccumulation ratio of 1 in aboveground biomass compared to the soil,” says Rufus Cheney, a U.S. Department of Agriculture research agronomist. “This is a very unique characteris-

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LENA MA, UNIVERSITY OF FLORIDA–GAINESVILLE

pected to have vitellogenin in their blood; however, male fish that have been exposed to estrogenic compounds will also have significant amounts. Although it is not yet known whether vitellogenin induction is the best endpoint to use for assessing health effects, the mechanisms have been well studied in fish, and the process is known to be estrogen-dependent. “We know that chemicals which bind to the estrogen receptor as agonists will induce vitellogenin. The model of concentration addition that we chose for assessing the activity of the mixtures is very much dependent on the fact that chemicals act by the same mechanism,” says Thorpe. If two chemical agonists act by the same mechanism of action on a particular endpoint, their effects will likely be additive. Thorpe and her colleagues found that combinations of estradiol-17β and 4-tertnonylphenol were additive, but combinations of estradiol-17β and methoxychlor were less than additive. The results suggest that estradiol-17β and 4-tert-nonylphenol induce vitellogenin via the same mechanism, but methoxychlor does not. “There is evidence in the literature that methoxychlor has to be activated to its estrogenic metabolite, HPTE. We think that this requirement for metabolic activation has something to do with the observed deviation from additivity,” says Thorpe. Although much of the attention surrounding the toxicology of mixtures has centered around chemicals that bind to the estrogen receptor, the concept of additivity has been applied to other groups of chemicals as well, says Peter de Fur, a biologist at Virginia Commonwealth University’s Center for Environmental Studies. “Probably the most well known groups are the dioxins, furans, and PCBs. They predominantly act through a common receptor mode of action, so this gives you a way to compare the potency of each one of those compounds individually and then all together,” he adds.

The brake fern isthe firstknow n arsenic hyperaccumulatorand hasenormouspotentialforphytoremediation ofcontaminated sitesw orldw ide.

tic, and that’s why [Ma’s] finding is so important.” The next step is to determine the molecular mechanisms of uptake enabling the fern to absorb, store, and sequester these huge amounts of arsenic, says Steve McGrath, a professor and senior scientist at the Institute of Arable Crops Research–Rothamsted in the United Kingdom. “That’s going to be the key to exploiting it,” McGrath adds. At the moment, researchers are unsure as to why the fern has such a strong affinity for arsenic, because it’s not an essential element. “The only thing we can think of is self-defense,” Ma says. “This plant is so poisonous that no insects or bugs can touch it.” Indeed, the arsenic levels observed easily surpass the U.S. EPA’s 5-ppm threshold for classification as an industrial-level hazardous waste. Another possibility is that the fern accumulates arsenic as a way of coping with its environment, detoxifying a toxic element present in the root surface. Ma’s group has found that in soils, by far the pre-

dominant form of arsenic is As(V), but in the plant itself, As(III) was the predominant form. Results presented at the American Chemical Society’s April meeting in San Diego showed that 47–80% of the arsenic found in the fern’s fronds was present as As(III), compared to 8.3% in the roots, indicating that the plant is capable of converting As(V) to As(III) during translocation from roots to fronds. Researchers see great potential for the fern’s use in remediating thousands of arsenic-contaminated sites worldwide. The plant has considerable biomass, grows fast, propagates easily, and is a perennial, so it could be harvested continually without reseeding. Plus, the fern is widespread, growing in areas with mild, sunny climates and alkaline environments where the arsenic is more easily extractable.

Government Watch

Because the fern also grows well in water, the researchers speculate that the plant’s roots could extract arsenic from water. Jianwei Huang, a plant biologist working as a consultant for Edenspace Systems Corp., which has licensed the fern for commercial development, is growing the plant in a hydroponic system. Results so far indicate arsenic removal rates five times higher than EPA’s current maximum limit of 50 ppb within 24 hours. Huang warns, however, that much research remains in optimizing the system, such as determining the number of roots necessary, their lengths, and the surface of root per unit of water. “Theoretically, it works,” Huang says, “but to determine whether it actually works, we’ll have to wait for the field demonstrations.” —KRIS CHRISTEN

replace the combustion unit. Offsite reductions, such as carbon sequestration, or obtaining CO2 credits by implementing efficient energy projects will be viable reductions, according to regulatory officials, provided the measures are proven “real, quantifiable, and permanent”.

Clean diesel at a high price?

Nitrates linked to bladder cancer period, from initial exposure to a cancer diagnosis, is 15 to 25 years, Weyer says. Using data collected from 1955 to 1988 on municipal water supplies, the researchers estimated each woman’s average nitrate exposure level, adjusting for a number of factors that might impact bladder cancer, such as smoking, age, education, physical activity, and fruit and vegetable consumption. Only municipal water supplies that had at least 90% of their water coming from a single source were included in the study. TONY FERNANDEZ, AMERICAN CHEMICAL SOCIETY

Nitrates in drinking water are statistically associated with an increased risk of bladder cancer at levels lower than the U.S. EPA standard of 10 parts per million (ppm), according to a University of Iowa study of almost 22,000 women. “We use a lot of nitrogen in fertilizer in the Midwest, and source waters in this area are impacted pretty heavily with nitrate,” says Peter Weyer of the University of Iowa’s Center for Health Effects of Environmental Contamination and the study’s lead author. Long-term, heavy use of nitrogen fertilizers in Iowa has resulted in nitrate concentrations in excess of 5 ppm in 30–40% of the state’s municipal water supplies, according to the study published in the May issue of Epidemiology (2001, 11 (3), 327–338). Weyer and his colleagues analyzed cancer incidences in women participating in the Iowa Women’s Health Study who were 55–69 years of age in 1986 when the study began and had used the same water supply for more than 10 years. They chose this group of women because the typical latency

Increasing levelsofnitrate in Iow a’smunicipaldrinking w atersupplieshighlighta callto tighten federalstandards.

U.S. EPA diesel fuel standards that reduce the sulfur content of diesel fuels by 2006 could lead to a sharp rise in price and diesel fuel shortages, according to an economic analysis published in May by the Energy Information Administration (EIA), a branch of the U.S Department of Energy. The final standards, signed by former President Clinton in December, require oil refiners to reduce diesel fuel sulfur content from 500 to 15 ppm by 2006. Low-sulfur fuel is needed to power cleaner diesel trucks and buses that can’t run on gas with high-sulfur content because the sulfur poisons the pollution control devices. The American Petroleum Institute and the National Petrochemical and Refiners Association have filed lawsuits against the rules, claiming they would cost the oil industry too much money and lead to fuel shortages. Frank O’Donnell, executive director of the environmental group Clean Air Trust, attacked the report as “an attempt to help the oil industry undermine the standards”. But its estimates, from 4.7 to 10.7 cents per gallon, are within the range of other analyses. U.S. EPA estimates increases of approximately 4 to 5 cents per gallon. The U.S. House of Representatives Science Committee, concerned about the economic impact of the standards, commissioned the EIA report. For a copy, go to http://www.eia.doe.gov/ bookshelf/environ.html.

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Environmental M News They found that women drinking water with average nitrate levels greater than 2.46 ppmthe uppermost quartilewere 2.83 times more likely to develop bladder cancer than women in the lowest nitrate exposure quartile of less than 0.36 ppm. Because there were only 47 cases of bladder cancer out of 21,977 women, however, the association was moderate, cautions James Cerhan of Mayo Clinic and a coauthor of the study. “It’s a very detailed analysis, and we adjusted for a lot of things that we know are risk factors for cancer,” Weyer says. “The association with nitrate in drinking water came up, and for bladder [cancer] it was a very interesting finding because it’s biologically plausible.” Nitrate can endogenously be converted to Nnitroso compounds, which are carcinogens. Alex Avery of the Hudson Institute, a conservative think tank, remains unconvinced. “I’m of

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strong opinion that [this] latest research isn’t any stronger than research that’s been done in the past and was rejected by the National Research Council (NRC).” The current 10-ppm standard was set in 1991 based on a 1951 survey by the American Public Health Association linking cases of methemoglobinemia, or blue baby syndrome, to nitrates in drinking water. Because no cases were observed below 10 ppm, EPA established the standard at this level. A 1995 NRC report concluded that the standard was adequate for protecting public health but did not consider whether the standard might be too stringent. The NRC did find, however, that epidemiological results were “inadequate” to support an association between nitrate exposure from drinking water and increased cancer rates. However, this latest study has several strengths over previous ones in that the researchers evaluated individual

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behaviors rather than a group. These results also suggest, to some, that EPA should raise its standard. Because blue baby syndrome is now virtually nonexistent, with only two cases reported since the mid1960s, Avery says he believes that the standard could be raised without any adverse health effects (Environ. Sci. Technol. 1999, 33 (17), 357A). In a recent review of the literature, Avery suggested that blue baby syndrome could be caused by gastrointestinal disorders as opposed to nitrates in drinking water (Environ. Health Perspect. 1999, 107 (7), 583−586). Weyer and Cerhan disagree. “Increasing the standard doesn’t make a whole lot of sense in terms of potential public health concerns with respect to cancer and other chronic disease concerns,” Weyer says. “At the same time, I’m not sure we need to lower it; we need to do more studies to get a better handle on what’s going on here.” —KRIS CHRISTEN

News M Briefs

Although the ability to link disease outbreaks with climate change doesn’t exist currently, the potential does, according to a recent report from the U.S. National Research Council. In Under the Weather: Climate, Ecosystems, and Infectious Disease, an NRC panel of independent scientists finds that numerous factors, such as public health services, population density, and travel patterns, greatly affect climate−disease linkages. It may be possible to provide early warnings of infectious disease outbreaks, the panel adds, if further research can elucidate the relationship between climate and disease. For a copy of the report, go to www.nap.edu. Industry secrecy and governmental silence may be limiting the public’s right to know about environmental and health threats, according to reports issued by OMB Watch, a nonprofit group that follows the White House Office of Management and Budget. Even in the age of information, rules issued by the U.S. EPA and the Justice Department force people to go to extraordinary lengths to get “public” accident information that is intentionally kept off the Internet, according to one report. A second report highlights the chemical industry’s success in convincing the U.S. Congress in 1999 to restrict public access to industrial information on chemicals with the poten-

tial for harm if an accident occurred. The reports are available at www.ombwatch.org. ISRI

Environmental improvement is the greatest success story of the past 30 years, according to the Index of Leading Environmental Indicators 2001, established by the Pacific Research Institute for Public Policy, a nonprofit dedicated to limited government. Compared to the decrease in crime and welfare cases, environmental improvement is dramatically more consistent. Statistics provide a perspective; according to the report, despite urban sprawl, 93% of U.S. land remains undeveloped, but alternative energy-producing windmills kill 39 bald eagles in California annually. The full report is available at www. pacificresearch.org.

The Institute of Scrap Recycling Industries, Inc. (ISRI), is requesting financial and organizational contributions from automakers to establish a nationwide program to recover mercury switches from automobiles before they are recycled. Many recyclables, such as cars or appliances, are tainted with mercury-containing devices. ISRI’s Design for Recycling initiative encourages preproduction planning to keep recycling as safe and efficient as possible. For more information, visit www.isri.org. Major policy options aimed at reducing carbon emissions could be implemented jointly without economic hardship for the United States, according to a study by the International Project for Sustainable Energy Paths. Rather than create new models, the researchers relied on peer-reviewed methodologies used in major U.S. analyses to review three domestic policies and an international emission allowance trading scheme. For a copy of Cutting Carbon Emissions at a Profit: Opportunities for the United States, go to www.IPSEP.org. Rural communities are being left behind in the rush to redevelop brownfields, concludes a report from the nonprofit National Association of Development Organizations (NADO). Lacking the technical expertise and private development funds of larger cities,

small communities lose out in the competition for federal matching funds for brownfields redevelopment. Their remote location inhibits economic growth, making it difficult to justify brownfields funding. Federal and state agencies should collaborate with regional development organizations to promote brownfields redevelopment, NADO recommends in this profile of 16 communities from 12 states. For a copy of Reclaiming Rural America’s Brownfields: Alternatives to Abandoned Property, go to www.nado.org. Although the 2000 Census reports that the U.S. population surge in the 1990s surpassed the 1950s Baby Boom, population stabilization through immigration quotas has dropped from most environmental advocacy agendas, according to a study by the Center for Immigration Studies. Among five developments, immigration is noted as the greatest contribution to population expansion. Urban sprawl, congestion, habitat loss, and destruction of open spaces demonstrate that the original 1970s Earth Day theory—that the total environmental impact was the product of the average individual impact—has been abandoned. The full report is available at www. cis.org. Laws that require polluters to prove that they can pay for cleanups in case of accidents are working and have not been a burden to industry, concludes a report from Resources for the Future, a nonprofit research organization. Industry predictions that the financial liability provisions of the Oil Pollution Act and the Superfund law would lead to skyrocketing damage claims and unaffordable insurance rates have not been validated. These laws help the government recover costs and foster the use of environmentally safer technologies, according to the report. Financial Assurance Rules and Natural Resource Damage Liability: A Working Marriage? is at www.rff. org.

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