waste more rigorously, which did not change the total daily waste production rate of 3.9 kilograms per bed per day but decreased group IV wastes by 80%—from 400 to 80 grams per bed per day—while increasing group III wastes. Subsequent burning of exclusively group IV waste led to a dramatic decline of PM and heavy metal emissions from the hospital’s incinerator. The group III waste was sterilized and burned in a municipal waste incineration plant. The researchers say that the increase in group III waste burning did not counterbalance the drop in emissions from the hospital incinerator, because many municipal waste incinerators are equipped with modern air pollution control devices. The vast majority of incinerators operating at hospitals, however, are not similarly equipped. Nevertheless, Alvim-Ferraz and Afonso found that even the reduced emissions emanating from the incineration of rigorously segregated group IV waste surpassed the legal emission limits by 1.3-fold for mercury, 20-fold for PM, and 90-fold for dioxins, underlining the need to equip medical waste incinerators at hospitals with air pollution control devices. Adds Alvim-Ferraz, “Appropriate equipment to control atmospheric pollution must be used to protect human health.” —ORI SCHIPPER
Removing endocrine disrupters from municipal landfill leachate Membrane-based treatment processes appear to be promising technologies for removing endocrine disrupters from municipal waste landfill leachate, according to research in this issue of ES&T (pp 3430–3434). Although the technologies can remove large amounts of the hormone-mimicking chemicals from sewage effluents, their rather high cost has prevented widespread use by wastewater treatment plants (WWTPs). Landfill leachate volumes are low, however, compared with WWTP effluents, making advanced treatment processes more economical for landfill leachate.
Although the estrogenic activity of untreated landfill leachate is within the range of WWTP influents, little attention has been paid to removing endocrine disrupters from municipal landfill leachate, presumably because many landfills contain a plastic bottom sealing to prevent leachate from coming into contact with the environment. Such barriers, however, typically begin to leak after about 12 years, according to Peter Behnisch, division leader of Life Sciences at SGS Germany, who has tested the estrogenic potency of landfill leachate in Japan and Germany. In addition, many older landfills do not even have
News Briefs Reacting to reactive chemicals The Occupational Safety and Health Administration (OSHA) needs to strengthen its regulation of reactive chemicals to prevent fires, explosions, and toxic releases, according to a petition by eight international unions and the American Federation of Labor–Congress of Industrial Organizations (AFL–CIO). Although the unions have been making similar petitions since 1995, their case was strengthened by a report released by the U.S. Chemical Safety Board (CSB) in September 2002, which called reactive chemical incidents a “significant chemical safety problem” that can cause major environmental damage. For more information, go to www. paceunion.org.
Farmers violating GM crop requirements A significant number of farmers are not complying with U.S. EPA requirements for growing genetically modified (GM) crops, according to a report by the Center for Science in the Public Interest (CSPI). If farmers grow GM corn that contains Bt toxin, they must plant 20% of their acreage with nonBt corn to prevent pesticide resistance. The report points to U.S. Department of Agriculture data showing that in 2002, 19% of all Bt corn farms in Iowa, Minnesota, and Nebraska were in violation of this “refuge” requirement, and 13% of them had no refuge whatsoever. CSPI believes the percentage of farmers in violation is higher than the biotechnology industry claims because small farms are typically not surveyed. CSPI recommends that EPA require biotech companies to make on-farm inspections and farmers to provide maps and seed-purchase records to the biotech companies. A copy of the report, Planting Trouble, is available at www.cspinet.org.
AUGUST 1, 2003 / ENVIRONMENTAL SCIENCE & TECHNOLOGY ■ 279 A
PHOTODISC
the compiled emission factors in EEA’s Emission Inventory Guidebook. However, Alvim-Ferraz argues that politicians should make an effort to standardize categories and that “there should be a unified classification to allow comparisons of emission factors.” Furthermore, because EEA’s and EPA’s compilations lack information on the composition of incinerated medical waste, “it is not safe to use these emission factors,” she says. To quantify how different hospital waste separation practices affect the incinerator emissions, AlvimFerraz and her co-worker, Sérgio Afonso, measured the concentrations of PM, arsenic, cadmium, chromium, lead, manganese, mercury, and nickel from the controlledair incinerator of a 300-bed hospital in Portugal. The usual waste treatment practice at this and other hospitals in Portugal is to burn what are defined as group III and group IV wastes, which are similar to the United States’ red bag and pathological classifications, respectively. However, Portuguese legislation requires only that group IV waste be incinerated at the hospital. Group III wastes need to be sterilized, but then afterwards can be dumped into the normal municipal garbage. The hospital set up a program to encourage workers to segregate the
Environmental▼News filtration is used, he says. Activated sludge processes have been shown to remove endocrine disrupters from wastewaters; however, some chemicals, including estrone, ethinylestradiol, and alkylphenols, are not completely eliminated (Environ. Sci. Technol. 2001, 35, 4697–4703). PHOTODISC
bottom sealings, says Anja Coors of Aachen University in Germany and lead author of the ES&T article. Despite being a source of endocrine disrupters, landfill leachate is not routinely tested for estrogenic chemicals. European Union (EU) and Japanese guidelines are being developed very slowly, and most of the landfills do the testing “just for fun”, says Behnisch. The same holds true for the United States, which has gotten bogged down with validating methods for testing and screening for endocrine disrupters. In the EU, a new Landfill Directive (1999/31/EC) requires that all new municipal waste landfills have bottom sealings, as well as leachate collection and treatment systems, Coors says. The directive must be implemented by 2009. General municipal waste landfills in Japan must also be equipped with a leachate treatment system, and the water quality of the leachate must satisfy national effluent standards, says Yasunori Kawagoshi of Kumamoto University, who has investigated the occurrence of endocrine disrupters in Japanese landfills. In some cases, advanced treatment systems such as adsorption to activated carbon are used, but more typically an activated sludge process or sand
Membrane technologies may protect the soil near landfills from endocrinedisrupting chemicals.
To tackle these problems, Coors and colleagues at Aachen University and Michigan State University tested two membrane-based treatment processes in parallel on raw leachate from a municipal landfill in Germany. In the first process, the leachate was treated by aerobic biological degradation followed by ultrafiltration and adsorption to activated carbon, and in the second process, it was treated by reverse osmosis. Although both processes were
2003 Green Chemistry Awards The products and processes honored by the 2003 Presidential Green Chemistry Challenge Awards are proof that environmental science helps improve the quality of life, according to a letter by President George Bush read at the ceremony on June 23. Over the eight years the awards have been given, nearly one-fourth have recognized chemical innovations related to polymers, according to Nina McClelland, chair of the American Chemical Society’s Board of Directors, who spoke at this year’s ceremony. True to form, two of this year’s five awards recognized innovations in polymer production. E. I. du Pont de Nemours and Co., in Wilmington, Del., was honored for developing a process that uses genetically altered Escherichia coli bacteria as a biocatalyst for creating 1,3propanediol, a key ingredient in a polymer that the company projects could be used in place of hundreds of millions of pounds of traditional polymers generated from petroleum feedstocks. The new technology eliminates hazardous materials and organic solvents and operates at a lower temperature. Richard Gross of Polytechnic University in Brooklyn, N.Y.,
280 A ■ ENVIRONMENTAL SCIENCE & TECHNOLOGY / AUGUST 1, 2003
capable of removing a large percentage of the estrogenic activity, which was determined as estradiol equivalents (EEQs), the first process was more effective than reverse osmosis. The researchers quantified the estrogenic response after treatment using a reporter gene assay with genetically modified human breast cancer cells. “There was significant response in some samples after reverse osmosis, but there was no significant response after adsorption to activated carbon,” Coors says. When expressed as EEQs, elimination was above 98.5% after adsorption to activated carbon and 97.2% after reverse osmosis. The researchers analyzed the untreated raw leachate for known xenoestrogens. They found high levels of bisphenol A (3.61 milligrams per liter), a chemical commonly used in the manufacturing of plastics, but did not detect nonylphenol, a breakdown product of a surfactant found in detergents, paints, pesticides, and personal care products. Although they did not test for steroids such as estradiol, they found that the levels of bisphenol A were high enough that bisphenol A alone could have been responsible for the observed estrogenic activity in the leachate. —BRITT E. ERICKSON
earned an academic award for his method of synthesizing polymers that use lipase enzymes derived from yeast as a biocatalyst. Traditionally, polyesters are created by using catalysts containing heavy metals such as zinc, manganese, tin, and antimony. A second award for a product harnessing microbes went to AgraQuest, Inc., of Davis, Ca., for Serenade, the first non-toxic, broad spectrum microbial fungicide that is compatible with both organic and conventional farming. The product is based on a patented Bacillus subtilis microbe. Shaw Industries, Inc., of Dalton, Ga., was honored for its PVC- and plasticizer-free EcoWorx carpet tile. Because both the nylon carpet yarn and the backing, which is made from waste coal fly ash, can be recycled to create more carpeting, the company bills it as a “cradle to cradle” product. Finally, Süd-Chemie, Inc., of Louisville, Ky., won an award for a new method of synthesizing a solid oxide catalyst that generates no wastewater, no nitrates, and only negligible amounts nitrogen oxides (NOx). In contrast, every 5000 tons of an older process generated 378,900 tons of wastewater, 14,300 tons of nitrates, and 3800 tons of NOx . —KELLYN BETTS
