A federal deadline is approaching for companies working with a specific form of engineered nanomaterial, following regulatory action taken by the Environmental Protection Agency earlier this month.
The EPA’s new rules governing multi-walled carbon nanotubes, designated PMN P-23-105, will take effect on January 4, 2027, giving industry a narrow window to prepare for compliance.
At the centre of the regulatory change is a Significant New Use Rule, known as a SNUR, which the agency formally published on November 5, 2026.
The SNUR places advance notification obligations on any business that plans to manufacture or process the nanotubes in a way that qualifies as a significant new use under the rules.
Crucially, the statutory definition of manufacture extends to importation, meaning overseas suppliers shipping the material into the United States are also caught by the requirement.
Companies that trigger the rule must file a Significant New Use Notice, or SNUN, with the EPA no fewer than 90 days before beginning the relevant activity.
That 90-day window is not merely procedural: no manufacture or processing may legally commence until the agency has completed its review of the submitted notice and reached a formal determination.
The EPA is then required to take whatever actions flow from that determination before any commercial activity involving the designated new use can proceed.
The chemical substance was previously the subject of a premanufacture notice and sits under an existing Order issued by the EPA under the Toxic Substances Control Act, commonly known as TSCA.
TSCA provides the legal foundation for SNURs, giving the agency authority to require advance notification when it identifies potential risks associated with new uses of chemical substances already under regulatory scrutiny.
Multi-walled carbon nanotubes are a class of engineered nanomaterials with applications across sectors including electronics, advanced materials, and energy storage, making the scope of the rules relevant to a broad range of industrial users.
The layered requirements, covering submission, agency review, formal determination, and mandated follow-on action, mean that companies will need to build significant lead time into any plans involving new uses of PMN P-23-105.
Legal commentary on the rules was published by Lynn L. Bergeson and Carla N. Hutton in the National Law Review on November 8, 2026, flagging the regulatory development for industry compliance teams.
With the January effective date now confirmed, businesses across manufacturing, importing, and processing sectors are expected to audit current and planned activities involving the substance against the new use designations.