DuPont disputes PFOA cancer claim - ACS Publications

Chemical giant DuPont is disput- ing a recent study that claims expo- sure to the perfluorooctanoic acid. (PFOA) used to manufacture Teflon and other ...
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Environmental▼News American Association for the Advancement of Science (AAAS), an international nonprofit group. The updated proposal clarifies that government-funded scientists working at universities or in consulting firms may be involved in peer reviews as long as their research doesn’t create a conflict of interest. The guidance now exempts from the peer review guidelines science related to decisions an agency might need to make quickly to protect public health, as well as mat-

ters related to national security and trade negotiations. Also, it allows reviewers to remain anonymous. OMB staff met with most of the critics and now many of the scientific organizations are giving this third try a green light, adding that some agencies could improve their peer review process. Yet most scientists also caution that the key to success lies in the implementation of the proposal. OIRA suggests that a committee co-chaired by the White House Office of Science,

Technology, and Policy and OIRA should meet periodically to discuss changes in peer review practices and oversee agency implementation. “We want to make sure that [the review committee] is transparent,” so outside scientists can see what the agencies are using in their peer review systems, Frankel says. The April 15 Revised Information Quality Bulletin for Peer Review can be found at www.whitehouse.gov/ omb/inforeg/peer_review041404.pdf. —CATHERINE M. COONEY

Chemical giant DuPont is disputing a recent study that claims exposure to the perfluorooctanoic acid (PFOA) used to manufacture Teflon and other fluoropolymers at one of its chemical plants in West Virginia causes an increased risk of cancer. The company was reacting to a study that found plant workers and neighbors whose drinking water contains the perfluorinated compound have cancer rates several times higher than those of the general population. Like perfluorooctane sulfonate (PFOS), which was once used to make the popular Scotchgard fabric protector, PFOA appears to be ubiquitous at low levels in humans living far from any obvious sources. The mystery of how these perfluoroalkyl acids get into people has prompted investigations by academic scientists, industry, and the U.S. EPA. PFOA is acknowledged to cause cancer in animals, but studies of industrially exposed workers have not shown a conclusive cancer link. A preliminary EPA risk assessment released last year raised the possibility that PFOA at levels close to those currently found in women’s blood might pose a developmental risk to children (Environ. Sci. Technol. 2003, 37, 201A–202A). EPA is due to release a more complete risk assessment this summer (www.epa.gov/opptintr/pfoa). However, in this case, the cancer concerns stem not from PFOA’s global distribution, but instead from

RACHEL PETKEWICH

DuPont disputes PFOA cancer claim

People working in and living around a DuPont plant where PFOA, or C8, is used to create Teflon pans have elevated cancer rates.

local releases. DuPont’s Washington Works plant, located on the Ohio River, has used PFOA—also called C8—for more than 50 years. For most of that time, DuPont released PFOA into the air, local landfills, and the adjacent Ohio River. Groundwater around the plant also contains the perfluoroacid. PFOA water concentrations near the Washington Works plant range from about 1 part per billion (ppb) to 8 ppb. This concentration is substantially less than the 150-ppb level of concern established by West Virginia in 2002. The West Virginia study was conducted by James Dahlgren, a toxicologist at the University of California, Los Angeles, on behalf of plaintiffs in a class action lawsuit filed against DuPont. The 2001 suit alleges that DuPont knowingly contaminated local water systems with PFOA and that the chemical causes adverse

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health effects. Dahlgren presented the data at the Society of Environmental Toxicology and Chemistry meeting in Prague, Czech Republic, in April this year. Dahlgren and colleagues compared cancer incidence from three different sources for three different groups: a survey of 599 residents living near DuPont’s Washington Works plant in West Virginia, unpublished health records of more than 5000 DuPont employees that were obtained as part of the lawsuit, and data for cancer prevalence in the United States as a whole. The class action lawsuit includes all nearby residents who have PFOA levels of at least 0.5 micrograms per liter in their drinking water. All the plaintiffs have lived in the area for at least a year. Dalgren and his colleagues found that plant neighbors and DuPont workers have similar kinds of cancer, with elevated rates for prostate cancer in young men and cervical and uterine cancer in women. They also found higher rates of uncommon cancers, such as nonHodgkin’s lymphoma, leukemia, and multiple myeloma. The kinds of cancers and their presence in young people point to PFOA exposure, Dahlgren says. “These are unusual cancers in young people, people between 40 and 50 years old. They are endocrine-disruptor-type cancers— prostate, breast, cervical—and this pattern has been seen in prior studies of workers involved with perfluorinated chemicals,” he adds. “It’s possible that the explanation is

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ing the health of populations were considered or analyzed,” Leonard charges. Meanwhile, DuPont is conducting its own $1 million survey of possible PFOA effects on 750 volunteer employees at the Washington Works plant. The goal is to compare the results of employees who work in the company’s Teflon unit, the area where PFOA is primarily used, and those who work elsewhere in the plant. —REBECCA RENNER

Gobbling up turkey oil It may not help reduce prices at the pump, but turkey oil is now available by the barrel from Renewable Energy Solutions (RES). Changing World Technologies collaborated with ConAgra Foods, Inc., to commercialize a thermal conversion process technology that makes a kind of biodiesel, which is an alternative fuel derived from biological material. The Carthage, Mo., plant is now producing 100–200 barrels per day out of leftovers from an adjacent turkey processing facility. The proprietary technology breaks down long organic chains into clean fuels (Environ. Sci. Technol. 2003, 37, 389A–390A). Turkey oil sells at the same rates as refined petroleum, and customers intend to use the oil for heating. The company also has more products, including fertilizer and natural gas, in the works. For more information, go to www.res-energy.com.

Can street sweepers clean the water? water pollution cleanup were presented at the American Society for Microbiology meeting, held in New Orleans in May. Nur Muhammad, the lead author of a study that surveyed residential, commercial, and high-traffic streets in Oxford, Ohio, says that street sweeping can be an effective tool to prevent runoff pollution. Muhammad and his colleagues at Miami University of Ohio found high levels of bacteria in the street sweepings from residential areas. While fecal coliform exceeded 100,000 bacteria per 100 milliliters (mL) in runoff water during summer months, the vehicles removed more than 4.5 million coliform bacteria per gram of sweepings. The highest amounts of lead were re-

“Ctrl-alt” recycle?

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Experts agree that street sweepers can help keep cities cleaner by removing dust, which causes air pollution, but 90 years after the first mechanized street sweeper debuted in Elgin, Ill., the jury is still out on whether they also help reduce water pollution. The first street sweeper was invented by John Murphy in 1914 and featured a mechanized front hopper and a three-wheel design that deftly maneuvered around horses. The vehicle proved quick and effective, easily out-competing a man and a shovel. However, city engineers have demanded greater performance and pollution control in the intervening years. The latest data in the debate over street sweeping’s efficacy for

Street sweeper technology has improved from early designs that used motorized brooms to later models that used vacuum techniques. Newer models, like this one, use regenerative air to push smaller particles off the pavement and into catchments.

Most electronics manufacturers operating in the United States recycle fewer than 2% of their computers, although many do not have documents to prove that any of their U.S. computers are recycled, according to the Silicon Valley Toxics Coalition (SVTC), a nonprofit activist group. The organization’s Fifth Annual Computer Industry Report Card notes that two U.S.based companies stand out from this trend, Hewlett-Packard and Dell. However, although these two companies adopted statements accepting responsibility for computers at the end of their lives, both still “barely managed to achieve a passing grade,” according to the report. To view a copy of the report, which provides a path for improving its performance, go to www.svtc.org/cleancc/pubs/ 2003report.htm#exec.

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some factor other than PFOA exposure, but the most likely explanation is exposure to PFOA and other perfluorinated compounds.” “Based on what we have seen, we question the scientific validity of the conclusion in the report,” counters Robin Leonard, principal epidemiologist for DuPont. For example, he says, the study did not control for other factors that might affect cancer rates. “There is no indication that other factors impact-