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December 28, 2011

EPA Publishes Proposed SNURs for CNTs

Lynn L. Bergeson

The U.S. Environmental Protection Agency (EPA) published on December 28, 2011, proposed significant new use rules (SNUR) for 17 chemical substances that were the subject of premanufacture notices (PMN). Of particular interest, seven of the PMN substances’ reported chemical names include the term “carbon nanotube” (CNT) or “CNT.”  EPA states that because of a lack of established nomenclature for CNTs, the Toxic Substances Control Act (TSCA) Inventory names for CNTs are currently in generic form, e.g., “carbon nanotube (CNT), multi-walled carbon nanotube (MWCNT), double-walled carbon nanotube (DWCNT), or single-walled carbon nanotube (SWCNT).” EPA uses the specific structural characteristics provided by the PMN submitter to characterize more specifically the TSCA Inventory listing for an individual CNT. According to EPA, all submitters of new chemical notices for CNTs have claimed those specific structural characteristics as confidential business information (CBI). The proposed rule includes the generic chemical name along with the PMN number to identify that a distinct chemical substance was the subject of the PMN without revealing the confidential chemical identity of the PMN substance. Comments are due January 27, 2012.

EPA notes that, since confidentiality claims preclude a more detailed description of the identity of the CNTs, if an intended manufacturer, importer, or processor of CNTs is unsure of whether its CNTs are subject to the proposed SNURs, the company can either contact EPA or obtain a written determination from EPA pursuant to the bona fide procedures at 40 C.F.R. § 721.11. EPA states that it is using the specific structural characteristics, for all CNTs submitted as new chemical substances under TSCA, to help develop standard nomenclature for placing these chemical substances on the TSCA Inventory. EPA has compiled a generic list of those structural characteristics entitled “Material Characterization of Carbon Nanotubes for Molecular Identity (MI) Determination & Nomenclature.”