EPA Issues Final SNUR For Multi-Walled Carbon Nanotubes (P-22-163)

On July 24, 2026, the U.S. Environmental Protection Agency (EPA) published a final significant new use rule (SNUR) for multi-walled carbon nanotubes (P-22-163) that were the subject of a premanufacture notice (PMN) and are also subject to an Order issued by EPA pursuant to the Toxic Substances Control Act (TSCA). 91 Fed. Reg. 46742. The SNUR requires persons who intend to manufacture (including import) or process these multi-walled carbon nanotubes for an activity that is designated as a significant new use to notify EPA at least 90 days before commencing that activity. The required notification initiates EPA’s evaluation of the conditions of use for the multi-walled carbon nanotubes. In addition, the manufacture or processing for the significant new use may not commence until EPA has conducted a review of the required notification, made an appropriate determination regarding that notification, and taken such actions as required by that determination. The final rule will be effective September 22, 2026.

Under the SNUR, the significant new uses for multi-walled carbon nanotubes (P-22-163) are:

• Protection in the workplace: Requirements as specified in 40 C.F.R. Section 721.63(a)(1), (a)(3) through (6), and (c). EPA states that when determining which persons are reasonably likely to be exposed as required for Section 721.63(a)(1) and (4), engineering control measures or administrative control measures shall be considered and implemented to prevent exposure, where feasible. For purposes of Section 721.63(a)(5), respirators must provide a National Institute for Occupational Safety and Health (NIOSH) assigned protection factor (APF) of at least 50 at the confidential site listed in the Order or at sites where batteries or the other confidential items listed in the Order containing the PMN substance are only recycled, or an APF of at least 1,000 at all other sites, prior to the receipt of exposure monitoring results, and in accordance with Table 2 of the Order once exposure monitoring results are available.

• Hazard communication: Requirements as specified in 40 C.F.R. Section 721.72(a) through (d), (f), (g)(1), (g)(3)(iii), and (g)(5). According to EPA, for purposes of Section 721.72(g)(1), this substance may cause: eye irritation, genetic toxicity, carcinogenicity, and specific target organ toxicity. Alternative hazard and warning statements that meet the criteria of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) and U.S. Occupational Safety and Health Administration (OSHA) Hazard Communication Standard (HCS) may be used.

• Industrial, commercial, and consumer activities: Requirements as specified in 40 C.F.R. Section 721.80(f). It is a significant new use to use the substance other than as an additive used in battery manufacture. It is a significant new use to process the substance without the use of engineering controls with an overall minimum efficiency of 94 percent. It is a significant new use to process for use or use the substance in the final battery when the concentration of the substance exceeds the confidential concentration listed in the Order.

• Release to water: Requirements as specified in 40 C.F.R. Section 721.90(a)(1), (b)(1), and (c)(1).