USA - Significant New Use Rule on a Certain Chemical Substance; Multi-Walled Carbon Nanotubes

The Environmental Protection Agency (EPA) has issued a Significant New Use Rule (SNUR) under the Toxic Substances Control Act (TSCA) for a chemical substance that is subject to both a premanufacture notice (PMN) and a TSCA order. 

The rule requires manufacturers, importers, and processors to notify EPA at least 90 days before engaging in any designated significant new use, allowing the Agency to evaluate the potential risks associated with that activity. 

The rule becomes effective on September 22, 2026, and the associated activity may not begin until EPA completes its review, makes the required determination, and takes any necessary regulatory actions.