EPA Petitioned to Stop Sale of 260 Products Containing Nano-Silver

The legal action is the first challenge to EPA's failure to regulate nanomaterials, which are made up of microscopic particles. One nanometer is one billionth of a meter. Nanotechnology encompasses techniques for taking apart and reconstructing natural substances such as silver at the atomic and molecular level.

Increasingly manufacturers are infusing consumer products with nanoparticle silver for what they believe to be its enhanced germ killing abilities. Nanosilver is now the most common commercialized nanomaterial.

The coalition is led by the nonprofit International Center for Technology Assessment, CTA, based in Washington, DC, a self-described nanotech watchdog.

The CTA found over 260 nano-silver products currently on the market such as household appliances and cleaners, clothing, cutlery, and children's toys, personal care products and coated electronics.

These toothbrushes from South Korea are said by the manufacturer to be certified as safe and harmless by the South Korean government.

Yet as the coalition's legal petition states, the release of nano-silver may be destructive to natural environments and "raises serious human health concerns."

"These nano-silver products now being illegally sold are pesticides," said George Kimbrell, CTA staff attorney. "Nano-silver is leaching into the environment, where it will have toxic effects on fish, other aquatic species and beneficial microorganisms. EPA must stop avoiding this problem and use its legal authority to fulfill its statutory duties."

Just as the size and chemical characteristics of manufactured nanoparticles can give them unique properties, those same new properties - tiny size, vastly increased surface area to volume ratio, high reactivity - can create unique and unpredictable human health and environmental risks, the coalition says.

While silver is known to be toxic to fish and aquatic organisms, recent scientific studies have shown that the nano form of silver is much more toxic and can cause damage in new ways. Exposures are occurring both during use and during disposal.

A study from Arizona State University published in April showed that washing socks treated with silver nanoparticles to reduce foot odor releases most of the nano-silver into the laundry discharge water, and ultimately into waterways where it could "potentially poison fish and other aquatic organisms," the coalition says.

A University of Missouri researcher published a study on April 29 showing that silver nanoparticles may destroy benign bacteria that are used to remove ammonia from wastewater treatment systems. The study was funded by a grant from the National Science Foundation.

"Because of the increasing use of silver nanoparticles in consumer products, the risk that this material will be released into sewage lines, wastewater treatment facilities, and, eventually, to rivers, streams and lakes is of concern," said Zhiqiang Hu, assistant professor of civil and environmental engineering in University of Missouri's College of Engineering.

"We found that silver nanoparticles are extremely toxic," said Hu. "The nanoparticles destroy the benign species of bacteria that are used for wastewater treatment. It basically halts the reproduction activity of the good bacteria."

The coalition's legal petition demands that the EPA regulate nano-silver as "a unique pesticide that can cause new and serious impacts on the environment."

It asks that the agency require labeling of all such products and assess health and safety data before permitting them to be marketed.

The EPA also is asked to analyze the potential human health effects, particularly on children and analyze the potential environmental impacts on ecosystems and endangered species.

"The law does not allow the agency to stand idle while a new legacy of toxic pollution emerges," said CTA Legal Director Joseph Mendelson.

Many of the products in the petition's appendix are meant for children - baby bottles, toys, stuffed animals, and clothing. Others create high human exposures such as cutlery, food containers, paints, bedding and personal care products.

Concerns over nano-silver were first raised by national wastewater utilities in early 2006. One then-new product, Samsung's SilverCare Washer, releases silver ions into the waste stream with every load of laundry.

In response, according to November 2006 media reports, EPA said that it would regulate nano-silver products as pesticides. However, one year later EPA published a guidance covering only the Samsung washer and allowing it to remain on the market.

Members of the petitioning coalition are: the Center for Food Safety, Beyond Pesticides, Friends of the Earth, Greenpeace, ETC Group, Center for Environmental Health, Silicon Valley Toxics Coalition, Institute for Agriculture and Trade Policy, Clean Production Action, Food and Water Watch, the Loka Institute, the Center for Study of Responsive Law, and Consumers Union.

To view the full petition, executive summary and product appendix, click here.

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