The U.S. Environmental Protection Agency (EPA) published a Federal Register notice on May 15, 2019, announcing the availability of a signed action identifying chemical substances for inactive designation according to the Toxic Substances Control Act (TSCA) Inventory Notification (Active-Inactive) Requirements rule. 84 Fed. Reg. 21772. The signed action, dated May 6, 2019, initiated a 90-day period after which substances identified as inactive will be designated as inactive. Inactive designations for chemical substances on the TSCA Chemical Substance Inventory are effective on Monday, August 5, 2019. Beginning August 5, 2019, manufacturers and processors will be required to notify EPA before reintroducing into commerce a substance currently identified as inactive on the TSCA Inventory. Manufacturers and processors can notify EPA via a Notice of Activity (NOA) Form B, found in EPA’s Central Data Exchange (CDX). Upon receiving such notification, EPA will change the designation of substances from inactive to active. Our July 31 2019, memorandum, “EPA Posts NOA Form B Materials before TSCA Inventory Inactive Designations Take Effect August 5,” provides links to EPA materials intended to help manufacturers and processors prepare for the inactive designations taking effect, as well as a detailed commentary. Companies with additional questions should contact Lynn L. Bergeson or Richard E. Engler, Ph.D., for assistance.