The Toxic Substances Control Act (TSCA) is a United States law, passed by the 94th United States Congress in 1976 and administered by the United States Environmental Protection Agency (EPA), that regulates chemicals not regulated by other U.S. federal statutes, including chemicals already in commerce and the introduction of new chemicals. When the TSCA was put into place, all existing chemicals were considered to be safe for use and subsequently grandfathered in. Its three main objectives are to assess and regulate new commercial chemicals before they enter the market, to regulate chemicals already existing in 1976 that posed an "unreasonable risk of injury to health or the environment", as for example PCBs, lead, mercury and radon, and to regulate these chemicals' distribution and use.

The 94th United States Congress was a meeting of the legislative branch of the United States federal government, composed of the United States Senate and the United States House of Representatives. It met in Washington, D.C., from January 3, 1975, to January 3, 1977, during the last two years of Gerald Ford's presidency.