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Posted: January 3, 2007
The first federal restrictions on nanotechnology could be coming soon
(Nanowerk News) In a major reversal, the U.S. EPA has determined that clothes washing machines that use silver ions as a disinfectant will have to be registered as a pesticide. Until now, the agency has not regulated nanomaterials, including silver ions, made of a bioaccumulating, persistent, and toxic metal. Yet EPA's decision may be meaningless, critics point out, because if the company deletes from its advertising the assertion that silver can kill bacteria, it won't have to register the washer.
The fact that a product can slip past the agency without being registered if the company doesn't claim that it can kill bacteria is a "quirk" of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and "it'll be intriguing to see where we go on this," says Andrew Maynard, science adviser to the Project on Emerging Nanotechnologies at the Woodrow Wilson International Center for Scholars. He and others are urgently calling for research into nanotechnology's potential environmental, health, and safety risks ("Safe handling of nanotechnology").
In an assessment updated in November, the project found that the number of consumer products made with nanotechnologies has increased by 70% since March 2006. The most prevalent nanomaterial being used is silver, now found in 47 products, Maynard says.
The wastewater treatment industry, in particular, has pointed out (pdf download 44 KB) that widespread use of household products, like the Samsung washer, that release silver ions into sanitary sewer systems could greatly increase silver concentrations in treatment-plant discharges, leading to adverse effects, such as bioaccumulation in fish and killing of aquatic life.
"We think it's great that EPA's going to regulate" this application, says Phil Bobel, manager of environmental compliance for the city of Palo Alto, Calif., and past president of Tri-TAC, a technical advisory committee on regulatory issues affecting wastewater treatment plants in California. "Whether it'll end up going far enough to actually keep that silver out of our systems, we don't know."
Advertisements by the manufacturer, Samsung Electronics, claim that nanoscale silver particles released during the wash and rinse cycles achieve 99.9% sterilization of bacteria and leave behind a residual silver coating on clothing to keep it smelling fresh for up to 30 days. Yet the EPA scientists aren't certain whether this is an advertising gimmick to sell more machines or if this is a novel material. Silver is already regulated as a pesticide in a number of products.
If Samsung submits a FIFRA registration application to EPA, the agency will determine whether and under what conditions the silver ions can be used. The company must supply scientific data to show that the use of the nanoscale silver particles won't pose an unreasonable risk to people or the environment.
A finding by EPA that the technology involves nanomaterials could affect a wide range of consumer products, scientists say.
Previously, EPA classified the machine as a device, meaning it wasn't subject to registration requirements under FIFRA. Concerns raised by states and various industries, however, caused the agency to reevaluate the product and determine in late November "that the silver ions are defined as pesticides, and therefore it needs to be regulated," says Ernesta Jones, an EPA spokesperson. "We don't know if it's a nanomaterial at this point," but if it is, "it would be the first federal restriction on nanotechnology."
Jones admits that if Samsung pulls pesticidal claims from its advertising, the company won't have to register the washing machine under FIFRA. Other companies have already taken note, removing statements of germ-killing capabilities in marketing their nanotech consumer products. A prime example is The Sharper Image, a company that has developed socks, slippers, and food containers embedded with silver nanoparticles, according to the Natural Resources Defense Council, an environmental group that relayed its concerns in a November letter to EPA.
"Failure to identify nanoscale pesticide ingredients should not be an excuse to circumvent the FIFRA registration requirements," NRDC wrote. "Because of the significant potential for serious environmental harm, EPA must conduct a comprehensive assessment of all products that use nanosilver as a pesticide."
EPA will issue a Federal Register notice in the next couple of months outlining the agency's position on the classification of silver-ion-generating washing machines, according to Jones.