By Rick Weiss
Washington Post Staff Writer
Friday, May 2, 2008
A coalition of consumer protection groups yesterday filed a legal petition with the Environmental Protection Agency seeking to halt the sale of consumer products containing microscopic nanoparticles of silver, an increasingly popular germ-killer that has raised environmental concerns.
More than 200 products -- including odor-resistant socks, baby bottles and clothes-washing machines -- are laced with specks of nanosilver, part of a larger nanotechnology revolution fueled by the novel chemical properties substances gain when honed to a few billionths of a meter.
But nanosilver's effects are not specific to harmful bacteria. Studies indicate it can harm aquatic organisms. And with the exception of one narrow rule that focuses on washing machines, the EPA has not addressed the potential risks of this new form of pollution, said George Kimbrell, staff attorney with the Washington-based International Center for Technology Assessment, which spearheaded the petition.
"EPA must stop avoiding this problem and use its regulatory authority to fulfill its statutory duties," Kimbrell said in a statement, adding in an interview that nanosilver is used in some stuffed animals and children's' clothing.
The petition asks the agency to stop the sale of products containing nanosilver and regulate the chemical as a pesticide, which would require toxicity studies and risk assessments to measure environmental and human health impacts.
An EPA spokesman said the agency already has "stringent regulatory standards" for pesticides, including those made with nanotechnology, but will review the petition.
There is disagreement about how, exactly, nanosilver should be regulated, said Andrew Maynard, chief science adviser for the Project on Emerging Nanotechnologies, set up by the Woodrow Wilson International Center for Scholars and the Pew Charitable Trusts. "But the petition raises a number of very valid points that have got to be taken seriously," he said. "Nanosilver and its use as a pesticide has got to be better regulated. It seems to be slipping under the radar."
A recent study showed that when socks impregnated with nanosilver are washed, silver particles end up in the drain water. Another found that nanosilver inhibits the growth of beneficial bacteria that help break down harmful chemicals in wastewater treatment plants.
Congress is currently considering a reauthorization of the five-year-old $1.5 billion National Nanotechnology Initiative and should take the opportunity to properly prioritize related health and safety research that needs to be done, said David Rejeski, director of the Project on Emerging Nanotechnologies.
"Research on nanosilver impacts should have started a year and a half ago," Rejeski said in an e-mail, "when we saw the commercialization of products using nanoscale silver increase rapidly."