tougher to control but also that chemical treatments will select for an even larger population of unwanted herbicide-resistant canola, she adds. “Research funding for ecological risk assessment is only 2% of what the U.S. Department of Agriculture spends on developing engineered crops,” Snow points out. She says much more investment is needed to answer ecological questions before GEOs are released. The regulatory framework needs to be fixed because it is very idiosyncratic and leaves gaps in coverage, Hallerman says. For instance, salmon is a food item covered by the U.S. Food and Drug Administration, even though the U.S. Fish and Wildlife Service would be a better choice, he adds. Genetically Engineered Organisms and the Environment: Current Status and Recommendations can be found at www.esa.org/pao/esa Positions/Papers/geo_ position. htm. —JANET PELLEY
Human pesticide testing gets qualified OK The controversial practice of testing pesticides and other toxicants on human volunteers received a qualified endorsement from a committee of ethicists and scientists, who released their findings as part of a National Research Council (NRC) report. The panel called for the U.S. EPA to set up a safety and ethics system similar to the U.S. Food and Drug Administration’s oversight of human drug testing and concluded that such testing is only justified when enough toxicity information exists to ensure that there will be no long-term harm to participants. According to the NRC report, which was released in February, the call for more human testing was triggered by the 1996 Food Quality and Protection Act, which tightened
safety standards for pesticides. The act introduced a 10-fold uncertainty factor to account for children’s susceptibility to pesticides, which was in addition to a 10-fold factor for uncertainties due to extrapolating from animals to humans. Data from toxicity tests involving humans will still be subject to the child uncertainty factor but not necessarily the extrapolation factor. Better science on which to base a regulatory decision “constitutes a societal benefit that can justify the conduct of a human dosing study,” the panel wrote. However, EPA should only consider such data if the dosing experiments are inherently safe and meet stringent scientific and ethical standards, which ensure that participants are protect-
News Briefs Wind goes mainstream Nearly three-fourths of the world’s wind power is now generated in Europe, according to a report by the American Wind Energy Association (AWEA) and the European Wind Energy Association (EWEA). As a result, wind energy should no longer be considered an alternative source of energy in the European Union (EU), says Corin Millais, EWEA’s chief executive. 2004 Global Wind Energy documents that the amount of electricity produced globally by wind turbines grew 26% in 2003. Although most of the growth was in Europe and the United States, the report notes that India installed 408 megawatts last year, cementing the country’s place as the world’s fifthlargest wind power producer. Denmark now generates more than 20% of its power from wind energy—the world record. Elsewhere in the world, Colombia installed its first utility-scale project last year, while wind power remains slow to take off in China. For more information, go to www.ewea.org.
Climate trading possibilities A mandatory cap-and-trade program combined with tradable efficiency standards to reduce greenhouse gases could be effective and generate support in most sectors of U.S. society, according to a consensus document developed by two nonprofit research groups, the Aspen Institute and the Pew Center on Climate Change. Rather than debate whether a reduction plan should be voluntary or mandatory, the diverse group discussed options for a national program that would be fair and economical. The result is not a full-blown program but rather a framework to begin a discussion, the authors say. A Climate Policy Framework: Balancing Policy and Politics is at www.aspeninst.org/eee.
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hormone gene proposed for commercial use in farm salmon into Japanese medaka fish. Because nontransgenic females preferred the large, engineered males over the smaller, wild males, 75% of the offspring carried the growth hormone transgene. But offspring with the transgene did not survive as well as their wild counterparts, and the researchers estimated that the population could go extinct in 50 generations, Hallerman says. The proposal to engineer salmon with the growth hormone is still in the regulatory pipeline, he warns. Canada has already initiated a monitoring program in response to concerns that canola plants are turning into “superweeds”. Traditionally, the canola plants that routinely pop up as unwanted volunteers in other crop fields have been controlled with herbicides, says Snow. But cultivation of transgenic canola resistant to the popular herbicide Roundup means not only that weedy volunteer canola is
Environmental▼News ed from long-term physical harm or exploitation and that the studies are scientifically necessary and valid. “Human studies involving pesticides, air pollutants, or other toxicants—as opposed to therapeutic agents—are particularly controversial, and because of [these concerns] EPA should subject these studies to the highest level of scientific and ethical scrutiny,” says committee co-chair James Childress, an ethicist at the University of Virginia, Charlottesville. As an example, the committee deemed acceptable pharmacokinetic tests that determine how humans metabolize toxicants because they advance scientific knowledge, provide unique data, and involve low doses. Biomarker studies, such as dosing volunteers with perchlorate to find out at what dose thyroid iodine uptake is inhibited, are also acceptable, provided they meet other safety requirements. To make certain such standards are followed, the committee recommends that EPA establish a Human Studies Review Board. Private studies should also comply with federal
ethical standards known as the Common Rule, which protects participants by requiring extensive oversight by an institution’s Internal Review Board and by asking for informed consent. EPA officials didn’t comment on the panel’s recommendations, but the agency announced last May that it intends to draft a rule on testing. As part of that process, EPA will evaluate the NRC report and public comments about the draft rule, according to spokesperson David Deegan. EPA hasn’t yet set a timetable for the proposal, he says. CropLife America, a Washington, D.C., trade association of pesticide manufacturers, welcomed the report. “As the [NRC] report identifies, it is in the public’s interest to maintain the availability of products that protect public health by controlling disease-carrying pests, such as mosquitoes, ticks, and cockroaches, and that ensure an abundant, affordable, highquality food supply,” a spokesperson says. Environmental groups fear that the report’s recommendations could
lead to a dramatic increase in human studies, which are typically third-party experiments conducted by pesticide companies and their contractors. “We are very concerned that the chemical industry will view the report as a green light to continue the highly unethical practice of dosing people with pesticides and industrial chemicals,” says Richard Wiles, senior vice president of the Environmental Working Group. Environmentalists view the studies as unethical because they put volunteers’ health at risk to benefit pesticide companies. The Environmental Working Group galvanized the debate on human testing with a report in 1998 that exposed chemical companies’ tests on uninformed Scottish college students. “The committee purposely set a very high bar when it comes to intentional human dosing studies, especially for those that do not promise health or environmental benefits,” says co-chair Michael Taylor, a senior fellow at Resources for the Future, a Washington, D.C.based economic think tank. —REBECCA RENNER
While studying African smoke plumes created by slash and burn agriculture, researchers have discovered a whole new category of carbon aerosol. The new particles, labeled tar balls, are significantly larger than soot and could play a role in air pollution and climate change. “Soot is well known and well studied,” says Peter Buseck, Regents Professor in the Department of Geological Sciences at the Arizona State University and one of the authors of the paper (J. Geophys. Res. 2004, 109, 1–9). “What was not known was that there are these other spherical particles that are considerably larger than soot.” These particles, he adds, suspend themselves in the troposphere and
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New particles found in smoke plumes
Transmission electron microscopy helped identify the presence of tar balls. The images above show irregular soot aggregates, and the inset on the left shows a tar ball.
thus may play an important role in both air pollution and global climate. Soot, for instance, is our atmosphere’s primary absorber of shortwave radiation. Tar balls differ from soot in three important aspects. First, tar balls have an amorphous shape and lack
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an internal crystalline structure. Second, they are an order of magnitude larger than soot particles, which typically measure around 20 nanometers. Finally, although soot is mostly composed of carbon atoms, tar balls contain a significant appear to amount of other elements, primarily oxygen.
