This month, the U.S. Environmental Protection Agency (“EPA”) formally responded to a petition for rulemaking filed almost seven years ago by the International Center for Technology Assessment and other groups who claim that nanosilver, a nanoparticle with enhanced antibacterial abilities used in hundreds of consumer products, has fundamentally different properties than its macro-scale silver counterpart, thus requiring special regulatory oversight.

In 2008, the group of non-governmental organizations filed a petition for rulemaking requesting that the EPA take a number of actions to regulate products containing nanosilver, including classifying nanosilver as a pesticide and requiring the registration of nanosilver products as new pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”).  In December 2014, the same group of NGOs filed a lawsuit under the Administrative Procedure Act seeking declaratory and injunctive relief for the EPA’s failure to respond to the 2008 petition. See Center for Food Safety et al. v. McCarthy; Case No. 14-cv-2131 (D.D.C.).  On March 19, 2015, the EPA issued a 23-page response, granting some of the petitioners’ requested actions and denying others. (A copy of the EPA’s response is available here.)

The EPA granted petitioners’ request to treat as pesticides under FIFRA products containing nanoscale silver if intended for “pesticidal purposes,” even in the absence of specific pesticidal claims.  However, the Agency denied the request to treat all products containing nanosilver as pesticides, claiming it lacks the foundation to do so.  “Pesticide” is defined, in part, by FIFRA as “any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest,” with a number of statutory and regulatory exclusions to the definition of “pest.” See 7 U.S.C. § 136(u).  EPA rejected petitioners’ position that nanosilver is specifically and solely used for its antimicrobial properties and that research shows no other significant commercially valuable use for nanosilver.  The Agency therefore announced that it will continue to apply its statutory and regulatory criteria to determine, on a case-by-case basis, whether a product is properly classified as a pesticide.

The EPA agreed to consider applications for pesticide products containing a new nanosilver ingredient under its FIFRA Section 3(c)(7)(C) authority.  It also granted petitioners’ request to review the health and safety impacts from use of a nanosilver ingredient in a pesticide product based on nano-specific data for the portion released as nanosilver.  In other words, the EPA will not rely upon data for the nano-particle’s macro-counterpart in assessing its safety for purposes of market approval.

Perhaps the biggest disappointment for petitioners was the EPA’s refusal to commit to take enforcement action against all nanosilver products currently on the market.  Specifically, the Agency denied petitioners’ request to use a particular enforcement strategy, including issuing stop sale and removal orders, to address unregistered pesticides sold or distributed in the United States.  This refusal was based on the EPA’s proclaimed lack of factual basis to conclude that all nanosilver products are pesticides, and therefore illegally sold or distributed.

This is not the first time a federal agency has been taken to court for allegedly failing to take adequate measures to safeguard human health and the environment against the potentially unique risks of nanomaterials in consumer products.  In 2011, a group of non-profits filed a lawsuit against the U.S. Food and Drug Administration (“FDA”) seeking an order compelling the FDA to respond to a 2006 petition for rulemaking on nanomaterials.   That lawsuit was dropped after the FDA issued two draft guidance documents related to the use of nanotechnology by the food and cosmetics industries.

In issuing industry guidance documents and exercising their regulatory authority, the FDA and the EPA have taken what may be viewed as guarded approaches to nanomaterials, which can be found in everything from sunscreens to sporting goods.  Both agencies have repeatedly announced their commitment to diligent oversight and continued research on the potentially unique behaviors and effects of these tiny particles while at the same time refusing to categorically assume that nano-products are unreasonably dangerous.  Though miniscule in size, the ability of nanoparticles to stir conflict is not to be underestimated.  Calls for increased regulation by interest groups are almost certain to continue despite the EPA’s latest response document, and more “nano-disputes” are likely to find their way into court.  We will continue to follow important developments on the Monitor.