EPA is amending significant new use rules (SNURs) issued under the Toxic Substances Control Act (TSCA) for certain chemical substances, which were the subject of premanufacture notices (PMNs) and significant new use notices (SNUNs). As a result of EPA's review of SNUNs for these chemical substances and based on new and existing data, EPA is finalizing amendments to these SNURs. Specifically, this action amends the identified SNURs to allow certain new uses reported in the SNUNs without additional notification requirements and modify the significant new use notification requirements based on the actions and determinations for the SNUN submissions.