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Ninth Circuit Orders Full EPA Review of Nanosilver Pesticide

A Ninth Circuit panel ruled Tuesday that the U.S. Environmental Protection Agency failed to follow its own rules when it approved the use of the new pesticide nanosilver on a short-term basis.

SAN FRANCISCO (CN) – A Ninth Circuit panel ruled Tuesday that the U.S. Environmental Protection Agency failed to follow its own rules when it approved the use of the new pesticide nanosilver on a short-term basis.

The three-judge panel unanimously sided with the Natural Resources Defense Council, finding the EPA did not cite substantial evidence that a fast-track approval of a nanosilver known as NSPW as a pesticide was in the public interest.

“After reviewing the conditional registration for substantial evidence, we conclude the EPA failed to support its finding that NSPW is in the public interest,” Circuit Judge Michael Melloy, sitting by designation from the Eighth Circuit, wrote. in the 23-page opinion. Ninth Circut Judges Richard Clifton and Paul Watford joined Melloy’s opinion.

Nanosilver is an engineered, smaller-particle form of silver advertised as having some of the same antimicrobial properties as the naturally occurring metallic element but diminishes the amount of silver distributed throughout the environment.

Trace amounts of silver can be found in a vast array of plastic and textile products including mops, trash cans, furniture, clothing, shower curtains, office supplies and luggage.

The metal has proven effective in the suppression of fungus, algae, mold and mildew. But because it is so widely used in various consumer products, it has a tendency to accumulate in the environment in unnatural concentrations – compromising ecology and wildlife.

Silver is the second most toxic metal found in fish, according to the Natural Resources Defense Council.

With this in mind, the company NanoSilver engineered nanosilver to have the same toxic-suppressant properties without the widespread risk of environmental accumulation.

However, questions remain whether nanosilver will be more dangerous in terms of its ability to accumulate into organic tissue, whether it be aquatic animals or humans.

With this in mind, the EPA granted conditional registration of nanosilver in 2015. With conditional registration, the EPA gets to bypass the traditional approval process and fast-track approval of a given pesticide if it can demonstrate public benefit.

The Natural Resources Defense Council argued the EPA failed to demonstrate this public benefit.

While Melloy acknowledged the EPA sufficiently demonstrated nanosilver would reduce the distribution of the metal in the environment, he said it failed to prove manufacturers would use the new material to any statistically significant degree.

“Because the substitution and no new-products assumptions are unsubstantiated, petitioners argue that the EPA’s public-interest finding is not supported by substantial evidence,” Melloy wrote. “We agree.”

The judges said the conditional registration is reserved for certain pesticides that could immediately address an urgent problem, as evidenced by the floor discussion of lawmakers during its passage.

“Clearly the objectives of the act are best served with the added flexibility to permit a new product to be used which will meet the stringent test of being ‘in the public interest,’” Sen. Patrick Leahy, who introduced the bill that allowed conditional registration in 2000, said.

The EPA argued the replacement of silver with nanosilver in products would proceed as a “a logical matter,” but the Ninth Circuit panel was unpersuaded. The panel vacated the conditional registration of nanosilver and directed the EPA to proceed with the standard and time-consuming process.

“This is an important victory for public health,” said Jennifer Sass, senior scientist with the health program of the Natural Resources Defense Council. “Nanosilver is known to be highly toxic to aquatic life, and may be hazardous to people. EPA rushed to judgement by approving it, leaving consumers to be guinea pigs. Now the agency must take a closer look at its potential to cause harm.”

The EPA did not respond to a request for comment by press time.

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