The Organization for Economic Cooperation and Development (OECD) has published the latest edition of the Developments in Delegations on the Safety of Manufactured Nanomaterials and Advanced Materials — Tour de Table. The Tour de Table compiles information provided by delegations on the occasion of the 22nd meeting of the OECD Working Party on Manufactured Nanomaterials (WPMN) in June 2022.  The Tour de Table lists U.S. developments on the human health and environmental safety of nanomaterials. Risk assessment decisions, including the type of nanomaterials assessed, testing recommended, and outcomes of the assessment include:

The U.S. Environmental Protection Agency (EPA) completed review of five low volume exemptions that included modified graphene materials and multi-walled carbon nanotube chemical substances. EPA granted one exemption, while the other four exemptions were denied or withdrawn before being denied. The Tour de Table states that EPA allowed the one exemption under conditions that limited human and environmental exposures to prevent unreasonable risks. Additionally, EPA reviewed and completed six premanufacture notices (PMN) for multi-walled carbon nanotube chemical substances. According to the Tour de Table, EPA regulated all six of the new chemical substances with a consent order “due to limited available data on nanomaterials.” The consent orders limited uses and human and environmental exposure to prevent unreasonable risks.

The Tour de Table lists the following new regulatory challenge(s) with respect to any action for nanomaterials:

•    Standards/methods for differentiating between different forms of the same chemical substance that is a nanomaterial;
•    Standardized testing for the physical properties that could be used to characterize/identify nanomaterials; and
•    Differentiation between genuinely new nanoscale materials introduced in commerce and existing products that have been in commerce for decades or centuries.
 

source: https://nanotech.lawbc.com