Rick Weiss, Washington Post, 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’

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.”