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Assessing and Managing Chemicals under TSCA

Chemical Substances Undergoing Prioritization

As required under section 6(b) of the Toxic Substances Control Act (TSCA), EPA must conduct a prioritization process to determine if chemical substances are a high- or low-priority for risk evaluation. 

On March 20, 2019, EPA initiated the prioritization process by issuing a list of 40 chemical substances and began the effort to designate 20 substances as “high priority” for subsequent risk evaluation and to designate 20 substances as “low-priority,” meaning that risk evaluation is not warranted at this time. On December 20, 2019, EPA finalized the designation of the 20 high-priority chemicals. On February 20, 2020, EPA finalized the designation of the 20 low-priority chemicals.