EPA is terminating the reporting periods for 234 chemical substances by amending the sunset dates on the list of substances, mixtures, and categories in the Toxic Substances Control Act (TSCA) section 8(d) model Health and Safety Data Reporting rule. Pursuant to 40 CFR 716.65, EPA has reviewed all of the substances listed in Sec. 716.120 and determined that at this time the Agency no longer needs continuing health and safety data reporting on these 234 chemical substances. For these chemicals, reporting under the section 8(d) model rule is no longer required except for those studies which were initiated before the end of the reporting period or were ongoing at the end of the reporting period. Persons who believe that EPA should not terminate the reporting requirements for these substances on the section 8(d) model rule may notify EPA and provide their reasons.