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October 4, 2017

EPA Promulgates Final SNUR for Bimodal Mixture Consisting of MWCNTs and Other Classes of CNTs

Lynn L. Bergeson Carla N. Hutton

On October 3, 2017, the U.S. Environmental Protection Agency (EPA) promulgated a final significant new use rule (SNUR) under Section 5(a)(2) of the Toxic Substances Control Act (TSCA) for the chemical substance identified generically as bimodal mixture consisting of multi-walled carbon nanotubes (MWCNT) and other classes of carbon nanotubes (CNT), which was the subject of premanufacture notice (PMN) P-11-482.  This action requires persons who intend to manufacture (defined by statute to include import) or process the chemical substance for a use that is designated as a significant new use by this final rule to notify EPA at least 90 days before commencing that activity.  Manufacture and processing for the significant new use is unable to commence until EPA has conducted a review of the notice, made an appropriate determination on the notice, and taken such actions as are required with that determination.  According to the June 8, 2017, proposed SNUR, the generic use of the PMN substance will be as a specialty additive.  Based on test data on analogous respirable, poorly soluble particulates and nanocarbon materials, EPA identified concerns for pulmonary toxicity and oncogenicity.  Based on test data for other nanocarbon materials, EPA identified concerns for environmental toxicity.  Under the SNUR, significant new uses are:

  1. Protection in the workplace: Requirements as specified in 40 C.F.R. Section 721.63(a)(1), (a)(2)(i), (a)(2)(ii), (a)(3), (a)(4), (a)(6) (particulate), and (c).  When determining which persons are reasonably likely to be exposed as required for Section 721.63(a)(1) and (a)(4), engineering control measures (e.g., enclosure or confinement of the operation, general and local ventilation) or administrative control measures (e.g., workplace policies and procedures) shall be considered and implemented to prevent exposure, where feasible.  A National Institute for Occupational Safety and Health (NIOSH)-certified air purifying, tight-fitting full-face respirator equipped with N-100, P-100, or R-100 cartridges, or power air purifying particulate respirator with an Assigned Protection Factor (APF) of at least 50 meets the requirements of Section 721.63(a)(4);
  2. Industrial, commercial, and consumer activities: Requirements as specified in Section 721.80(k) and (q).  A significant new use is any use involving an application method that generates a vapor, mist, or aerosol;
  3. Disposal: Requirements as specified in Section 721.85(a)(1), (a)(2), (b)(1), (b)(2), (c)(1), and (c)(2); and
  4. Release to water: Requirements as specified in Section 721.90(b)(1) and (c)(1).  Any predictable or purposeful release of a manufacturing stream associated with any use of the substance from any site is a significant new use other than the water releases described in the manufacturing process of PMN P-11-482.

This final rule is effective November 2, 2017.