Size Is Everything

“Groups Petition EPA To Ban Nanosilver in Consumer Goods”

“A coalition of consumer protection groups yesterday [May 1] 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.” Rick Weiss reports for the Washington Post May 2, 2008.

Nanotechnology is the manipulation of materials less than 100 nanometers in size, that is one billionth of ameter, 1/100,000 of a human hair, 1/500 of a human red blood cell, ½ the diameter of a DNA molecule. Nanoparticles do exist naturally. Some volcanic ash and salt in ocean air are nanosize. Unintentionally produced nanoparticles include those emitted in car and truck exhaust. Because of their unique size and shape, nanos are like completely new substances. They have new and unknown chemical, electrical, magnetic and imaging properties. For instance, on a nano scale, gold is a liquid; inert metals like platinum are reactive.

The story behind the washing machines is strange but true.

Last summer, EPA Region 9 quarantined at the Port of Oakland several thousand Samsung's SilverCare Washing Machine that used silver nanoparticles Samsung believed consumer would go crazy for a washing machine that uses silver ions to kill germs in clothing.

But the Bay Areas’ water treatment plant operators and EPA officials feared the silver ions would kill the antibacterial germs that the wastewater plants use to treat the wastewater. The EPA only has the authority to regulate new chemical compounds, as silver is not a new substance. Under the Toxic Substances Control Act, EPA does have the authority to regulate pesticides, and the danger from these machines after all was their ability to kill pests.

After holding the washers at the docks for a period of time, the machines were allowed to be shipped to the retailers. After negotiations with EPA, Samsung agreed to remove the component that produced the silver nano particles.