Environmental t News Synthetic fragrances perfume lake sediments
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KERI HORNBUCKLE
he scent of perfume behind ical impacts of synthetic fragrancproduction is increasing over time, the ears has timeless allure, es, Hornbuckle says. and that is reflected in the concenbut perfume raises scientific Hornbuckle and her colleagues trations of these musks that are eyebrows when it persists in the dated two sediment cores from accumulating in sediment,” says environment. Research published Lake Erie and Lake Ontario and Chris Metcalfe, an ecotoxicologist in this issue of ES&T (pp 5629– analyzed the concentrations of five at Trent University (Canada). 5635) documents, for the first polycyclic and two nitro musk fraResearch on Lake Michigan time, a historical profile of shows that sewers serve synthetic-fragrance conas the primary conduit centrations in lake sedifor fragrances, which ments. The results show a wash down the drain afdramatic rise in environter being applied to skin, mental exposure over the hair, and clothing, Hornpast 15 years—a potential buckle says. She has also concern if these persistent detected fragrances in contaminants turn out to rural air at concentrahave biological effects, extions higher than those perts say. of the most commonly Synthetic musk fraused pesticides. grances, far cheaper than “Thus far, the Europeand chemically dissimilar an Chemicals Bureau has to the natural fragrance concluded that HHCB obtained from musk deer and AHTN [Tonalide, a and musk ox, are found in polycyclic musk] are not common household deterPBTs [persistent, bioacgents, soaps, shampoos, cumulative, and toxic and cosmetics, says Keri substances], and the EuResearchers prepare to sample a core of Great Lakes sediment Hornbuckle, an environropean Scientific Comfor synthetic fragrances, which are virtually nonbiodegradable mental engineer at the mittee for Cosmetics and and are accumulating in this portion of the ecosystem. University of Iowa and a Non-Food Products has coauthor of the study. They have grances. They found that HHCB affirmed their continued safe use also been detected in human fat concentrations actually declined in consumer products,” says Dan and breast milk. slightly from 1979 to 1990; howSalvito, an environmental scienU.S. manufacturers used 6500 ever, after 1990, levels of HHCB tist at the Research Institute for t of synthetic musks in 2000, the doubled in only 8 years. The dry Fragrance Materials, an industry last year for which data are availweight concentrations of fragrancassociation. able. The U.S. EPA lists HHCB es in sediment are in the parts-perHowever, Europe has phased (Galaxolide), the most common million range. out nitro musks over concerns fragrance compound, as a highThe concentration of HHCB that they are carcinogenic and enproduction-volume chemical; >1 over time mirrored the trends in docrine-disrupting, says Roland million lb/year are imported or U.S. consumption of all fragrancKallenborn, an environmental produced. In addition, synthetic es, including synthetic musks, chemist at the University Centre in fragrances persist in the environterpenes, and other compounds, Svalbard (UNIS; Norway). Recent ment, accumulate in animals, and levels of which have also risen studies are indicating that polycyhave an affinity for fat—all traits significantly in the past decade, clic musks may have sublethal efof persistent organic pollutants. Hornbuckle says. Industry would fects in fish; they bind to estrogen These properties, combined with not provide the researchers with receptors and act as an antagonist the sheer volume used, worry reconsumption data for individual to vitellogenin, an egg yolk precursearchers, who have begun to track fragrances. sor protein, Metcalfe says. the environmental fate and biolog“This research indicates that —JANET PELLEY 5588 n Environmental Science & Technology / SEPTEMBER 15, 2006
© 2006 American Chemical Society
ERIN AMWEG
Who would have thought that banning a class of pesticides from household products would result in so many environmental problems? As ES&T reported last year (Environ. Sci. Technol. 2005, 39, 497A–498A), Don Weston, adjunct professor of ecotoxicology at the University of California, Berkeley, found toxic levels of pyrethroids in creeks flowing through Sacramento, Calif. Weston’s latest paper, published in this issue of ES&T (pp 5817–5822), examines how piperonyl butoxide (PBO) increases the toxicity of these insecticides that are bound up in stream sediments. PBO is a chemical commonly added to pyrethroid sprays because it stops cellular enzymes from breaking down the insecticides, increasing their lethality. Pyrethroids are less toxic to humans than the organophosphates that they have replaced in consumer insecticides. However, pesticide manufacturers have not adequately tested whether py-
Small streams and creeks meandering through urban environments are slowly becoming contaminated with pesticides washing off lawns and the foundations of houses.
rethroids are harmful to small crustaceans living in stream sediment, where the pesticides are now building up after washing off suburban lawns. Weston’s interest in the environmental effects of PBO was piqued in the summer of 2005 when Sacramento County officials began an aerial spraying program for mosquitoes, to combat West Nile virus. The pesticide was a mix of 60% PBO and 6% pyrethrins. Pyrethrins are natural insecticides produced by certain species of the chrysanthemum plant, and pyrethroids are their synthetic counterparts. Weston wanted to know what would happen when the PBO washed off city streets and into the local creeks where he had already found high levels of pyrethroids. “I felt it was an opportunity that could not be passed up,” he says, noting that, because of health concerns, California officials rarely conduct aerial spraying anymore. Plus, nobody had ever examined how a pesticide synergist might interact with legacy pesticides. When Weston sampled creeks flowing through the sprayed area, he found widespread occurrence of PBO at concentrations of 2–4 ppb. He then took sediment from the creeks back to the lab. He had previously noted that the creek mud was poisonous because of pyrethroids washing out of local neighborhoods, so he mixed the samples with clean mud to cut the toxicity. Then, he spiked the samples with 4 ppb of PBO and introduced hyalella, small bottom-dwelling crustaceans that are sensitive to pesticides. He found that adding the PBO doubled the mortality rate. Weston says that the interaction between a relatively benign ingredient like PBO and pesticides already in the creek is something
News Briefs Lead paint in Asia
Lead remains present at high levels in household paints sold in some Asian countries, according to a survey published in the September issue of Environmental Research (2006, 102, 9–12). In some interior paints marketed in China, India, Malaysia, and Singapore, scientists found lead levels well over 180,000 ppm. The U.S. limit is 600 ppm for new paints; however, the standard for existing paints is 5000 ppm. Household paints pose a particular hazard to children, who are exposed through hand-to-mouth behaviors and through play in soil with lead dust. Some Asian countries regulate lead content in paint, but others do not. The authors note that companies selling lead-based paints in one country sometimes market lead-free paints elsewhere.
TCE risk assessment
Enough science exists to evaluate the impacts of trichloroethylene (TCE) on human health, a National Research Council (NRC) committee concluded in July. The U.S. EPA released a draft assessment for TCE in 2001. The report carried implications for cleanup requirements for the widely used degreasing agent that is now found on military and manufacturing sites across the U.S. Remediating these sites is estimated to cost billions of dollars. Animal research and epidemiological studies of human populations show that TCE has carcinogenic effects. The NRC also called for new analyses of EPA’s data. Still, the NRC noted that not enough data are available for creating a dose–response model and suggests that a linear-response model should determine future guidelines.
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New consequences of household pesticides
Environmentalt News that the U.S. EPA has not addressed in its regulations. In fact, he thinks that the agency has not even collected any data to consider the issue. Weston’s suspicion was somewhat confirmed in an email ES&T received from EPA. “We do not have data to show that applying PBO to a water body increases the toxicity of any pesticide that is already present,” wrote EPA spokesperson Enesta Jones. Weston’s coauthor, Michael Lydy, an associate professor of zoology at Southern Illinois University, Carbondale, says that the
problem of pesticide synergists may be widespread. “We know that DDT is still at high concentrations in sediments,” he says. “It may also synergize as well.” Lydy says that he is now applying for grants to study other U.S. streams. The new study “underscores the complexity of pesticide regulation,” says the director of California’s Department of Pesticide Regulation, Mary-Ann Warmerdam. She says that California must work with local water boards and pesticide manufacturers to protect the environment.
To do so, California is beginning a reevaluation of 600 pyrethroid products. The state is one of the largest U.S. markets for pyrethroids, and their use there has climbed in recent years. In 2000, pesticide companies and agriculture producers applied 695,000 lb of pyrethroids in California. In 2005, that climbed to 1.1 million lb. These numbers do not include the pyrethroids applied by consumers in bug sprays and lawn-care products, but Warmerdam suspects that the levels are equivalent. —PAUL D. THACKER
Fungi partly disarm asbestos
FR ANCESCO TURCI
mechanism, the team observed a decrease in oxidative stress, finding fewer base-pair changes in Asbestos poses well-known health In their new work, Fubini and guanosine chains when the fungi hazards to people disposing of old co-workers show that several funwere present. attic insulation and other building gi—Verticillium, Paecilomyces, and The next step, Fubini says, is to materials. But large deposits of the Fusarium species—removed iron see whether the fungi make the asfine, fibrous rocks also occur natufrom crocidolite and chrysotile. bestos less harmful in live cells or rally in some parts of the world. The Paecilomyces and Fusarium other in vivo experiments. Another One technique to experiment would partially disarm aslet the fungi do their bestos is to let fungi work for longer perido the work, suggests ods to see how much new research pubof the iron in the filished in this issue bers is extracted. of ES&T (pp 5793– The other path5798). ways through which Asbestos comes asbestos can be in many forms, and harmful are not so researchers coneasily disarmed, she tinue to argue over notes. The size alone how each type beof asbestos fibers has haves toxicologiproven damaging, cally. The chrysotile something that fungi form comes from cannot change. This serpentine rock and physical trait makes is slightly less harmfungi less than ideal ful than crocidolite, for cleaning up conSoil around Italy’s Balangero mine, the largest asbestos mine in Europe, the most dangercentrated sites, such contains chrysotile asbestos fibers. ous form, according as buildings. “Howto the U.S. EPA. Previous work by species also suppressed the creever, if you don’t have any other researchers led by Bice Fubini of ation of hydroxyl radicals in viway to treat large areas with spilled the University of Turin (Italy) contro from the fibers (Verticillium asbestos,” she continues, “it’s betfirmed that some species of fungi fungi did so only for crocidolite). ter than nothing.” could make chrysotile’s iron less The authors suspect that the funSuch “bioweathering” of asbesreactive. Once inhaled into the gi produce a chelating molecule tos minerals by fungi is “really an lungs, iron can react with cells to that binds to the reactive iron in interesting idea to mitigate or recreate hydroxyl radicals that damasbestos fibers and thus prevents mediate these fibers,” says Geoff age DNA. These mutations may the formation of hydroxyl radiPlumlee, co-chief for the U.S. Geolead to cancers or other maladies. cals. Although they did not see the logical Survey’s earth materials 5590 n Environmental Science & Technology / SEPTEMBER 15, 2006
and the availability of iron for later chemical reactions. Dodson also raises the question of possible effects of breathing in the fungi themselves. Still, Fubini’s team suggests that remediating asbestos-laden soils would be useful before activities such as building construction mobilize the fibers. Fungal remediation may eventually be applied around the largest asbestos mine in Europe, known as Balangero, in Turin (Italy), where the team’s chrysotile samples originated. Fubini notes that asbestos lines the bottom of a nearby lake as well as the steppes around the mine, and her team has been working with mining officials at the site. Although the mining company has yet to apply fungi, it is working to stabilize the soil and keep it from spreading to other areas. Low-cost fungi may be an additional attractive alternative, Fubini says, to make the soil there somewhat safer. —NAOMI LUBICK
“Fruit farmers, florists, and clockmakers” ODY HERMENS
Joop Hermens will become ES&T’s newest associate editor in January 2007. Hermens is the head of the environmental toxicology and chemistry research group at the Institute for Risk Assessment Sciences (IRAS) at the University of Utrecht (The Netherlands), and he has been a member of ES&T’s editorial advisory board since 2001. Hermens’s “work for ES&T has been groundbreaking. Joop was the principal editor for our special issue on ecotoxicology,” published December 1, 2004, says Jerald Schnoor, the editor of ES&T, “and now we are receiving many more papers in this crucial area of envi-
ronmental science.” Schnoor predicts that Hermens “will continue to lead our efforts in ecotoxicology and human health.” To that end, Hermens says he would like to see ES&T accept more papers on multiple stresses and ecosystems effects, examined with tools such as genomics. He would also like to see the journal embrace new arenas of research, including human and environmental health. Hermens has always been interested in mixtures. “I like a puzzle,” he says. As a student initially intrigued by both physics and chemistry, he chose chemistry. After teaching chemistry for several years, Hermens went to the University of Utrecht to complete his Ph.D. work on mixtures of aquatic pollutants. He joined the faculty there in 1983 and has since ad-
News Briefs Pesticides in children
When researchers studied pesticide levels in immigrant farmworkers, they were surprised to find very high concentrations in their children. The scientists are now calling for better education for farmworkers to protect their children (Am. J. Ind. Med. 2006, doi 10.1002/ajim.20354). For the study, scientists measured urine samples from 60 children 1–6 years of age for metabolites of organophosphorus pesticides. These insecticides are widely used in agriculture. They then interviewed the children’s mothers to establish possible exposure routes. Of the farmworkers studied, 40% of the mothers and 30% of the fathers had not received training in pesticide handling, a violation of U.S. EPA regulations. Many children lived in homes where farmworkers did not shower immediately after work, and in most households, workers changed contaminated clothing inside their dwellings.
Biofuels require subsidies Oil prices have seen a sustained increase since 2004, and consumer demand for biofuels is likely to accelerate in coming years, according to a report by the Organisation for Economic Co-operation and Development. However, the organization notes that very few countries have enough raw materials to produce biofuels at a cost that can compete with petroleum products without government subsidies. The study forecasts increased biofuel usage over the next 10 years. Consumption will raise market demand for maize, wheat, oilseeds, and sugar. The report predicts very strong growth in ethanol production in Brazil, Canada, and the U.S. but does not comment on likely changes in the EU because the bloc’s biofuels directive has not yet been enacted. In the U.S., producing more corn-based ethanol would limit increases in maize exports.
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and human health project. “From my perspective, it’s a pretty new and unusual way to go,” he says, that raises questions about rock types as well as concepts for future research. The study is important because it indicates that fungi can bind iron and neutralize a potential pathway to create hydroxyl radicals, says Ron Dodson of ERI Consulting. However, he emphasizes that these “chemical interactions pose only one facet of the toxicity of fibrous dust.” Past research has found that the morphology of asbestos alone increases cancer risks. Dodson also says that he is “not sure how applicable the model would be outside of a scientific test” because the mineralogy and therefore iron content of asbestos deposits can vary naturally across landscapes. Crocidolite incorporates more iron into its internal structure than does chrysotile, which holds iron on its surface— with implications for treatment
Environmentalt News vised more than 15 graduate students, working with a team that continues to tease apart the combined effects of multiple chemicals in the environment. In 2004, Hermens won the Society of Environmental Toxicology and Chemistry’s Environmental Education Award, and his comparison of environmental scientists to “fruit farmers, florists, and clockmakers” is emblematic of his flair as an educator. Fruit farmers deliver tangible, useful goods to society; the analogy in the environmental sciences would be techniques, tools, or models, he explains. Florists deliver aesthetically pleasing products, equivalent to the mechanistic underpinnings of chemical interactions that a scientist might elucidate. In his work, Hermens has been both a florist and a farmer, so to speak. “In the past, we did a lot of
work on trying to develop models to predict ecotoxicity or bioaccumulation in organisms,” he says. His research group works on distinguishing general modes of action in ecotoxicology and developing models for predicting ecosystem effects of so-called baseline toxicants; their results have been routinely applied in regulating new and existing chemicals in Europe. Hermens has coauthored >140 peer-reviewed research publications and has served as the head of 2 European Commission projects, on fate and transport of pollutants and quantitative methods of tracking them. More recently, Hermens’s work has shifted to quantifying the actual exposure in dose–effect relationships with whole organisms, as well as in cellular bioassays. Bioavailability in natural environments remains key, he comments.
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“I think we can still gain a lot of insight” into how toxics stay available to different life forms, a topic that may have been ignored in the past decade, in his estimation. Now, Hermens says, the real challenge is clockmaking. An environmental clock, he explains, can be fixed by looking at the whole picture and determining the mechanistic components and how they work together over time. Hermens urges his fellow researchers to be clockmakers who consider whole ecosystems and integrate their multiple components. “I’m really interested in things that are more mechanistics-based or processes-oriented, where people try to understand what is going on at the molecular level and at the same time, at the individual, population, and ecosystems level,” Hermens says. —NAOMI LUBICK
