On April 17 and May 22, 2026, Japan designated 117 PFHxS-related substances, long-chain perfluoroalkanoic acids (LC-PFCAs) and their salts, medium-chain chlorinated paraffins (MCCPs), and chlorpyrifos as Class I Specified Chemical Substances (Class I SCS)—the most stringent regulatory category under the Act on the Evaluation of Chemical Substances and Regulation of Their Manufacture, etc., also known as the Chemical Substances Control Act (CSCA). What are Class I SCS? Class I

Background At the twelfth meeting of the Conference of the Parties to the Stockholm Convention on Persistent Organic Pollutants (SC COP-12), held from 28 April to 9 May 2025, Parties adopted amendments to Annex A of the Convention to list three additional persistent organic pollutants (POPs): the pesticide chlorpyrifos and two groups of industrial chemicals, namely long-chain perfluorocarboxylic acids (LC-PFCAs) and related substances, and medium-chain chlorinated paraffins (