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Chemical Regulation

US EPA finalizes list of 20 high-priority chemicals

Agency to begin 3-year review of the substances’ risks to human health, environment

by Britt E. Erickson
December 23, 2019

The US Environmental Protection Agency has finalized the list of the next 20 high-priority chemicals that will undergo evaluation under the Toxic Substances Control Act. The agency will determine over the next 3 years whether the chemicals pose unreasonable risks to human health and the environment.

High-priority substances

• 7 chlorinated solvents

• 6 phthalates

• 4 flame retardants

• Formaldehyde

• 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8,-hexamethylcyclopenta[g]-2-benzopyran (HHCB), a fragrance additive

• 1,3-butadiene, used in manufacturing polymers.

The list contains the same 20 high-priority chemicals that the EPA proposed in March. They include: seven chlorinated solvents, six phthalates, four flame retardants, formaldehyde, a fragrance additive, and 1,3-butadiene, which is used to make polymers.

The EPA must finalize documents clarifying the scope of the evaluations for each of the 20 chemicals by June 2020. Those documents provide a snapshot of the hazards, exposures, conditions of use, and susceptible subpopulations that the agency will consider in the assessments.

The American Chemistry Council, which represents US chemical manufacturers, commended the EPA for achieving “another milestone in the effective and efficient implementation of TSCA.” The group, as well as the EPA, pointed out that designation of a chemical as a high priority does not necessarily mean that it poses a high risk to human health or the environment. “It simply means the high priority substances will now undergo the TSCA risk evaluation process,” ACC says in a statement. “These risk evaluations must focus on the hazard and exposure potential of a designated high priority substance under its conditions of use.”

The EPA has yet to finalize its proposed list of 20 low-priority chemicals, which will not be subject to further evaluation. The agency plans to do so early next year. In comments submitted to the EPA, environmentalists claim that the agency has insufficient toxicity data to determine if the proposed low-priority chemicals are nonhazardous.



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