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February 13, 2020

EPA Issues Proposed Registration Decision for New Nanosilver Product

Lynn L. BergesonCarla N. Hutton

The U.S. Environmental Protection Agency (EPA) announced on February 12, 2020, that it is seeking public input on a proposal to incorporate a new nanosilver pesticide product into textiles to combat odors, discoloration, and other signs of wear.  The proposed registration decision is for NSPW Nanosilver, and the proposed pesticide product, Polyguard-NSPW Master Batch (Polyguard), will be incorporated into textiles to suppress bacteria, algae, fungus, mold, and mildew, which cause odors, discoloration, stains, and deterioration.  According to EPA, based on its human health and ecological risk assessment, it has preliminarily determined that the new active ingredient in Polyguard meets the regulatory standard under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) for use as a materials preservative in textiles.  EPA invites public comment on its proposal and preliminary findings.  Comments are due March 13, 2020.  More information is available in Docket ID EPA-HQ-OPP-2020-0043

EPA notes that NSPW Nanosilver was the active ingredient in a previous conditional registration that it granted in 2015, for use as a materials preservative in textiles and plastics.  As reported in our May 31, 2017, memorandum, that decision was challenged, and the U.S. Court of Appeals for the Ninth Circuit “vacated it on grounds that EPA’s public interest finding for granting the registration was without support in the record.”  EPA states that the currently proposed product “is solely for use in specified textiles; therefore, Polyguard will have a more limited use authorization than the previously vacated conditional registration.”  EPA notes that Polyguard will be formulated as a master batch, meaning that NSPW Nanosilver would be embedded within plastic beads or pellets, in contrast to the previous product registration, which was in the form of a liquid suspension.