Nanosilver Registrations by the U.S. EPA: Timeline of its Legal History

Nanosilver is in the spotlight again, as last month the EPA filed a brief responding to the most recent cases brought against its 2015 conditional registration of an antimicrobial nanosilver by Nanosilva LLC. This is the second case of its kind, with the first conditional registration occurring in 2011 by HeiQ Materials AG that was also petitioned against by NRDC. With nanomaterials making innovative strides, their regulatory history may set the standards for future registrations. The timeline below provides a basic overview of some of the most important events.

September 2008 - HeiQ Materials AG applies to register AGS-20 with EPA

August 2009  – Nanosilva LLC applies to register NSPW-L30SS (antimicrobial pesticide, 1% nanosilver)

November 2009 - FIFRA Scientific Advisory Panel meets to discuss assessment of nanosilver and other nanoscale pesticides, recommends to EPA that each nanosilver should be assessed on a ‘case-by-case’ basis

December 2011 - EPA conditionally registers HeiQ’s AGS-20 as an antimicrobial/preservative in textile products containing <0.01% silver by weight. Requires HeiQ to perform more tests.

January 2012 - NRDC petitions Court to review EPA’s conditional registration of AGS-20

January 2013 - NRDC vs EPA: Court finds that EPA was supported by substantial evidence to base risk assessment on 3-year old toddlers as opposed to 9-month infants. However, the court found that the EPA broke one of its own rules; when a margin of exposure (MOE) is less than or equal to 1000, the EPA should consider this a risk concern. Under one of the calculated scenarios, the MOE was 1000, thereby should be considered a risk concern.

December 2013 - EPA amends AGS-20s registration to lower the maximum application rate (19 ppm) for surface coating, and reduced the set of textiles and fibers that can be treated.

May 2015 - EPA conditionally registers NSPW-L30SS as an antimicrobial additive. Requires that Nanosilva perform more tests.

July 2015 - NRDC as well as the Center for Food Safety and International Center for Technology Assessmentfiles petition against Nanosilva’s NSPW-L30SS’s conditional registration. Petitioners contend that 1) Nanosilva should not get more time to submit data, and 2) disagree with EPA’s public-interest finding.

March 2016 - EPA files a brief responding to the Nanosilva petitions on the basis that 1) the EPA only officially imposed data requirements on Nanosilva simultaneously with its granting of NSPW-L30SS’s conditional registration, therefore more time should be granted, and 2) EPA’s finding that nanosilver is in the public interest was supported by substantial evidence.