Carbon Nanomaterials Consortium Proposes TSCA Consent Agreement

Posted on April 14, 2011

On April 6, 2011, the NanoSafety Consortium for Carbon (NCC) sent a proposed testing consent agreement for carbon nanotubes and graphene nanosheets to Chemical Control Division of the Environmental Protection Agency (EPA).  [See related story from October 2010.]  Under Section 4 of the Toxic Substances Control Act (TSCA) (or 40 CFR § 790 through 799), EPA can enter into an enforceable consent agreement with a manufacturer or processor to develop data needed for regulatory oversight.  In the procedures laid out by 40 CFR §790.22, EPA can initiate a public time-limited negotiation between EPA, the manufacturers/processors, and “interested parties” (defined by those individuals “who submit written requests to participate in or monitor negotiations.”  In part, EPA will not enter a consent agreement if a consensus cannot be reached in the timeframe allowed by law nor will it enter an agreement that is considered “inadequate by other interested parties who have submitted timely objections … which provide a specific explanation of the grounds on which the draft agreement is objectionable.”

NCC is proposing to test representative compounds from up to four different categories of nanomaterials: single-walled carbon nanotubes (CNTs), double-walled CNTs, multi-walled CNTs and graphene nanosheets.  Effects on inhalation toxicity will be measured, using a 90-day study duration and, quite possibly, using non-validated methods (i.e. in vivo instillation of test substance as opposed to use of an inhalation chamber or nose-only exposure scenario).  The consortium members are hoping that “any testing completed under the testing agreement will replace and satisfy the toxicity testing requirements in any signatory’s Section 5 TSCA consent order,” and possibly preclude the need for any later “significant new use rules” (SNURs) issued under TSCA Section 5.

NCC is also proposing an interagency collaborative approach, whereby the National Institute of Standards and Technology would purify and supply all test materials for EPA approval prior to signing the agreement.  The characterization of the nanomaterials would be done by the US Army Corps of Engineers Engineer Research and Development Center, based on OECD or ISO criteria. Finally, workplace assessments of facilities operated by agreement signatories would be conducted in conjunction with the National Institute for Occupational Safety and Health.

EPA has yet to officially respond; however, if they agree with the consent agreement approach, then the Agency will start a six-month public negotiation period with NCC and any interested parties.