Environmental ▼News Another brominated flame retardant in the environment ew research published in this issue of ES&T, (pp 3247–3253) provides yet another example of why brominated flame retardants continue to fascinate scientists interested in the fate, transport, and bioavailability of chemicals in the environment. In the paper, Amelie Kierkegaard and her colleagues at Stockholm University report the first peer-reviewed data showing that decabromodiphenyl ethane (DeBDethane) is present in Sweden, where very little of the compound is believed to be used. DeBDethane is added to textiles and plastics such as the ones used in electronics products to render them less flammable. It serves as a replacement for Decabromodiphenyl ether (Deca-BDE), the most widely used polybrominated diphenyl ether (PBDE) flame retardant in the world. Unlike Deca-BDE, DeBDethane produces no polybrominated dibenzo-p-dioxins when heated, and DeBDethane’s manufacturer, Albemarle Corp., promotes it as meeting Germany’s strict dioxin ordinances. However, the new research indicates that DeBDethane may not be a suitable replacement for Deca-BDE in Europe, says Ake Bergman, a colleague of Kierkegaard’s at Stockholm University and an expert on brominated flame retardants. Albemarle Corp. has not disclosed how much of the flame retardant, which it markets as Saytex 8010, it produces. However, Kierkegaard says that the company claims that it does not export “large amounts” to Sweden. Nevertheless, she and her group detected the compound in 25 of the 50 Swedish sewage plants where they looked for it. They also identified the compound in the air of a Swedish electronics dismantling facility, in
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Researchers from the University of Stockholm tested sludge from 50 sewage treatment plants throughout the country, and they found DeBDethane in samples from half of those plants (the ones marked with an orange dot).
sediment from The Netherlands, and in water piping insulation. Kierkegaard is quick to point out that the researchers detected very low levels of DeBDethane, on the order of tens of nanograms per gram (dry weight) in most cases. The highest levels she detected were approximately 100 nanograms per gram in sludge; however, she stresses that the results need to be regarded as estimated concentrations because the method she used to detect the DeBDethane was not opti-
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mized for the compound. In all cases, greater amounts of Deca-BDE were found in the tested samples, she adds; those levels were approximately 1.4 to 50 times higher. One of the reasons that the findings are notable is because DeBDethane, like Deca-BDE, was expected not to be an environmental concern because of its large molecular size and low water solubility. “We were thinking that [Deca-BDE] will not enter the biological system and it will not be bioavailable, but © 2004 American Chemical Society
this has been proven wrong,” explains Mehran Alaee, a research scientist with Canada’s National Water Research Institute. Those assumptions were demolished in the past few years by research showing that Deca-BDE is indeed bioavailable and that people can take it up. Most recently, Heather Stapleton of the University of Maryland has shown that DecaBDE is unstable in the environment but persists nonetheless because it degrades into the more stable lower-brominated compounds associated with other flame retardant formulations (Environ. Sci. Technol. 2004, 38,
Arctic chemistry may explain perfluorinated mystery Atmospheric degradation of the fluorotelomer alcohols used to protect carpets and fabrics from stains can explain the presence of long-chain perfluorocarboxylic acids, including perfluoroactanoic acid (PFOA) in arctic animals, according to research in this issue of ES&T (pp 3316–3321). The new research describes atmospheric reactions that oxidize telomer alcohols to create PFOA and longer chain perfluoro-
carboxylic acids and carboxylates. Fluorotelomer alcohols are precursors to many perfluorinated products, including PFOA, a surfactant that has widespread applications in chemical manufacturing, aircraft production processes, and some electronic products. The U.S. EPA is now investigating PFOA because of concerns about the compound’s long residence time in humans and the possibility that at
News Briefs Examining causes of conflict The United Nations Environment Programme’s (UNEP) Governing Council formally approved a new sciencebased program to explore the links between environmental degradation and violent conflicts at its annual meeting in March. Only a few case studies show that environmental threats can cause warfare, and very few hardand-fast scientific facts explain the links between such altercations and social oppression such as starvation, says Nick Nuttall, a UNEP spokesperson. Researchers will study how factors such as desertification, water shortages, and mass migrations interact to trigger warfare. The move comes on the heels of UNEP’s successful pilot project to head off conflict on the Caspian Sea. For more information about the Environment and Security Initiative (ENVSEC), go to www.iisd.org/natres/security/envsec.
Green energy investment To help ensure that the electricity produced by green power sources meets consumer needs, Technology Partnerships Canada, part of the federal agency Industry Canada, has begun investing in technologies that will improve the performance and cost-competitiveness of sources such as solar and wind power. Industry Minister Lucienne Robillard says that supporting green energy options is key to reducing greenhouse gases under the Kyoto Protocol, which Canada signed in 2002. In April, the agency announced that it has awarded Xantrex Technology, Inc., $7.2 million (Canadian) to create new technologies to regulate the amplitude, frequency, and current. For more information about this project, visit http://tpc.ic.gc.ca.
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Scientists don’t yet know how DeBDethane is getting into the environment, but they suspect that it could be leaking out of electronics products such as computers.
8A–9A). The same may hold true for DeBDethane, Alaee worries. Studies with rats indicate that DeBDethane has low oral toxicity, although some research suggests that may be due to the compound’s poor bioavailability. Both Alaee and Kierkegaard plan to look for DeBDethane in biota. DeBDethane is also similar to Deca-BDE in that both are difficult to analyze in the laboratory. Researchers like Kierkegaard and Alaee say that the analytical difficulties inherent in analyzing for the compounds are the main reason why their presence in the environment wasn’t reported previously. DeBDethane’s extremely insoluble nature made it very difficult to get into a solution, Kierkegaard says; she ended up succeeding with a combination of acetone, tetrahydrofurane, and toluene. Kierkegaard also notes that her success in finding the compound in environmental samples was aided greatly by her success in obtaining a standard sample from Albemarle. Kierkegaard plans to determine how likely it is that DeBDethane debrominates in the environment or in biota. She is currently gathering sewage sludge samples from around the world to see how widespread DeBDethane may be. —KELLYN BETTS
