News Briefs
Farmers unprepared for methyl bromide ban
Contaminant levels detected in air and dust samples from residential apartments near where the World Trade Center (WTC) towers once stood pose little health risk, according to a new report from the U.S. Agency for Toxic Substances and Disease Registry (ATSDR). The samples were collected from Nov. 4 to Dec. 11, 2001, and analyzed for contaminants could be irritants or have long-term health implications. Only the dust samples showed significantly higher levels of contaminants than what was found in comparison areas not affected by the WTC collapse, but even these levels were well below occupational standards, according to the report. Public Health Investigation to Assess Potential Exposures to Airborne and Settled Surface Dust in Residential Areas of Lower Manhattan can be accessed at www.atsdr.cdc.gov.
Strawberry growers want to continue to use methyl bromide past the 2005 phaseout date under the Montreal Protocol.
Diesel–cancer risk examined
emptions from the 2005 phaseout date, which was mandated in 1998 under the Montreal Protocol. The effort to replace methyl bromide has lagged because pesticide manufacturers do not want the expense and risk of registering new substitute products that will not have a large and profitable market, according to U.S. Department of Agriculture (USDA) officials. But some scientists and environmentalists say that the problem lies with the agricultural industry’s unwillingness to abandon reliance on single “silver bullet” chemicals and adopt a systems approach, such as integrated pest management. Methyl bromide is a broadspectrum soil fumigant that kills pathogens, insects, and weeds before planting crops such as tomatoes and strawberries, says Ken Vick, senior national program leader at USDA’s Agricultural
Diesel emissions are the primary culprit behind Americans’ one in 2100 risk of developing cancer from breathing outside air—500 times the Clean Air Act’s protective threshold of 1 in 1 million, according to a recent report by the U.S. Public Interest Research Group, a national public interest advocacy group. Dangers of Diesel: How Diesel Soot and Other Air Toxics Increase Americans’ Risk of Cancer examines the cancer risk of 33 hazardous air pollutants, focusing on five from mobile sources: diesel soot, acetaldehyde, benzene, 1,3 butadiene, and formaldehyde. Diesel emissions represented 89% of the increased cancer risk, 60% of which come from nonroad vehicles such as construction and farm equipment. For a copy of the report, go to www.uspirg.org.
specific crops. However, the methyl bromide market is relatively small compared to other pesticides such as atrazine, and manufacturers can’t justify the costs for registering new products for this market, says Vick. If pesticide alternatives are not available or cut too much into profits, farmers could go out of business, he predicts. More than 56 U.S. growers and farm organizations submitted requests to EPA for exemptions on Sept. 9; Canadian applications were due at Environment Canada by Oct. 30, but thanks to a cold winter climate, Canada has fewer users of methyl bromide and does not expect many applications. In addition, Canada has been working with grain millers since 1991 to adopt alternatives, such as heat treatment, and this program has cut methyl bromide use in half, from 100 to 50
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WTC dust safety reaffirmed
Research Service. USDA research indicates that methyl bromide will have to be replaced by a wide variety of pesticides used in combination to target specific pests on USDA–ARS
The lack of alternatives to methyl bromide, a pesticide that depletes the stratospheric ozone layer, is driving companies in the United States and Canada to apply for ex-
Environmental▼News of methyl bromide, the Protocol for the first time will also allow exemptions for uses where the ban would cause economic disruption, says Cavadias. Despite the difficulties experienced by the United States and Canada, a handful of countries have already successfully phased out use of methyl bromide, including Indonesia, Denmark, and The Netherlands, says Kristin Schafer, program coordinator with Pesticide Action Network North America, an environmental group. Farmers in these countries have moved to a variety of options, including compost, soil solarization using clear plastic mulch, and alternative pesticides. In addition, much of the plant nursery business in the United
States has also dropped methyl bromide in favor of amending soils with compost and using pesticides selectively, according to the principles of integrated pest management, says Harry Hoitink, plant pathologist at Ohio State University. New research shows that the microorganisms in healthy, organicrich soil activate genes in plants that boost resistance to pathogens and insects, he adds. Efforts by companies to continue using methyl bromide past 2005 come as the United Nations Environment Programme warns in a September 16 report that the ozone layer remains vulnerable during the next decade, even with full Montreal Protocol compliance. —JANET PELLEY
Solar power competition The students at the University of Colorado at Boulder who designed this home wanted to demonstrate that solar power can be applied to almost any house. In the process, the Boulder team beat out students at 13 other U.S. universities and colleges to win the Department of Energy’s (DOE’s) first solar decathlon competition, which was held on the grounds of the pedestrian mall in Washington, D.C. in early October. Space heating and cooling are the largest users of energy in residential buildings, and the Boulder team earned high points for its superior ability to maintain a “comfort zone” in the home’s interior through natural ventilation, as well as heating, cooling, and humidity controls, using a minimum The award-winning solar house designed by students at the University of Colorado–Boulder is meant to resemble “an everyday amount of energy. The house, which has 65 single American home”. crystalline module solar photovoltaic cells on its roof capable of producing 30 kilowatt-hours of energy on a sunny day and uses only commercially available components, was also able to consistently harvest solar energy in amounts equal to or greater than the house’s electrical requirements. “People are coming to our house to get ideas for their own houses,” said Mike Wassmer, a second-year graduate student in Building Systems Engineering at Boulder who has been working on the project for one-and-a-half years. A student team from the University of Virginia won second place in the competition largely because of their home’s innovative design, which features recycled copper and wood on the building’s exterior. “We wanted to show that it’s really possible to take waste materials and recycle them into things that are far more usable,” says Josh Dannenberg, an architecture student who graduated from Virginia last May. The Virginia entry also boasts what the team claims to be the world’s first residential luminaire, a mirror dish on the roof that provides natural daylight to areas without windows. The 10-day contest required students to design and build solar-powered houses that blend aesthetics and modern conveniences with maximum energy production and efficiency. An international panel of experts judged the homes. “The Solar Decathlon proves that solar energy is practical today,” said DOE Secretary Spencer Abraham when conferring the awards to the winning teams. In addition to DOE and its National Renewable Energy Laboratory, the awards were sponsored by BP Solar, The Home Depot, Electronic Data Systems, and the American Institute of Architects. For more information, go to www.solardecathlon.org. —KELLYN S. BETTS
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tons per year, says Alex Cavadias, section head of ozone protection programs for Environment Canada. Over the same period, usage in the United States has declined slightly, from about 29,000 to just under 24,000 metric tons, according to EPA data. Countries still have to forward exemption requests that meet the critical use criteria outlined by the Montreal Protocol to the Technology and Economic Assessment Panel of the United Nation’s Ozone Secretariat for a final decision sometime in February or March 2003, says Vick. The Montreal Protocol allows the use of ozonedepleting chemicals to continue past their phaseout dates, if no alternatives are available. In the case
