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June 23, 2012

Recent Developments in NRDC’s Case Concerning EPA’s Conditional Registration of Nanosilver

Lynn L. Bergeson

On April 16, 2012, the Natural Resources Defense Council (NRDC) filed its brief in its lawsuit against the U.S. Environmental Protection Agency (EPA) concerning EPA’s conditional registration for HeiQ AGS-20, an end-use product containing nanosilver. NRDC filed suit on January 26, 2012, in the U.S. Court of Appeals for the Ninth Circuit (California) against EPA, seeking to limit public exposure to the nanosilver’s use in clothing, baby blankets, and other textiles and prevent EPA “from allowing nanosilver on the market without the legally-required data about its suspected harmful effects on humans and wildlife.”

In its April 16, 2012, brief, NRDC argues that EPA’s decision that HeiQ AGS-20 will not cause unreasonable adverse effects on human health was not supported by substantial evidence. According to NRDC, in calculating the risks to human health, “EPA failed to evaluate the risks to infants, even though they have an especially high likelihood of exposure to AGS-20 because they are more likely than other age groups to chew on textiles coated with it.” NRDC states that had EPA properly taken infants into account, application of its own risk criteria “would have shown that AGS-20 poses unacceptable risks, and thus may have ‘unreasonable adverse effects.’” NRDC further argues that EPA likewise failed to consider the risk of aggregate exposures from other nanosilver on the market. Had it done so, NRDC states, EPA’s analysis would have shown that registering AGS-20 creates unacceptable risks. NRDC concludes that, because EPA’s finding of no “unreasonable adverse effects” rested on “significantly understated risk assessments,” its decision is not supported by substantial evidence and must be vacated.

On April 23, 2012, the International Center for Technology Assessment, Center for Food Safety, Friends of the Earth, Beyond Pesticides, Center for Environmental Health, and Institute for Agriculture and Trade Policy filed a motion for leave to file a brief as amici curiae in support of NRDC. According to the motion, counsel for amici contacted the parties seeking their consent. NRDC consented, while EPA and Intervenor, HeiQ Materials AG, took no position.

The amici argue that, as stakeholders whose organizational and membership interests will be harmed by the conditional release of HeiQ AGS-20 nanosilver pesticide products, as well as by the regulatory precedent EPA’s action “sets more broadly” for U.S. oversight of nanotechnology, nanomaterials, and nanosilver pesticides, they have “a strong interest in presenting their concerns regarding the conditional registration of HeiQ, as well as offering the Court the broader ‘nano-world’ perspective surrounding this specific approval action.” According to amici, because EPA ignored “the hundreds of other nano-silver pesticide products also available,” these products will create significant aggregate exposures for which it did not account. Finally, the amici state, “EPA already has a blueprint and legal impetus for responsible oversight of these nano-silver pesticide products including AGS-20, in the form of a 2008, still-unanswered legal petition submitted to the agency by these same Amici.”

On June 14, 2012, EPA filed its answering brief, arguing that NRDC lacks standing to challenge EPA’s decision because NRDC has not demonstrated that it or its members face an injury that is “actual or imminent,” rather than “conjectural or hypothetical.” EPA states that, on the merits, its determination that HeiQ AGS-20 will not cause unreasonable adverse effects to consumers “is reasonable and supported by substantial evidence in the record.” According to EPA, it “conservatively estimated potential consumer exposure to nanosilver from HeiQ AGS-20, assuming, among other things, that 35% of the silver contained in an AGS-20 treated textile that is chewed or worn could be ingested or absorbed as nanosilver, and that a three-year-old child could be exposed to a new textile daily for six months.” Despite data gaps concerning HeiQ AGS-20, EPA determined it had sufficient evidence to conclude “that even a three-year-old chewing and wearing a new AGS-20 treated textile every day for six months could potentially be exposed to no more than 1/1000th of the quantity of nanosilver which did not cause any adverse health effects in relevant scientific studies.” Given the low risk, EPA states that it reasonably concluded that HeiQ AGS-20 will not cause unreasonable adverse effects to consumers, and its risk assessment “warrants substantial deference from the Court.”

Amici briefs supporting EPA’s position are due 14 days after June 14, 2012 or June 28, 2012.