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Chemical Regulation

EPA faces TSCA risk evaluation overload

Agency takes on 20 more chemical assessments after missing deadline to complete previous 10

by Britt E. Erickson
September 10, 2020 | A version of this story appeared in Volume 98, Issue 35

The US Environmental Protection Agency is moving ahead with risk evaluations for 20 high-priority chemicals under the Toxic Substances Control Act (TSCA), even though the agency has yet to complete several evaluations already in progress. The EPA finalized the scope of the next 20 evaluations Sept. 4, along with a list of companies responsible for paying for the reviews.

Next 20 high-priority chemicals

7 chlorinated solvents
6 phthalates
4 flame retardants
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 EPA has been struggling to meet its deadlines under amendments to TSCA enacted in 2016. The agency missed a June deadline to complete the first 10 chemical risk evaluations under the revised law. So far, the agency has completed assessments for just 2 of the chemicals—methylene chloride and 1-bromopropane. The EPA is now scrambling to complete the remaining 8 evaluations before the end of the year.

The 20 new assessments are also behind schedule. The EPA was over 2 months late in releasing the scoping documents. The timer started ticking when the agency identified the 20 chemicals in December 2019. It is supposed to complete the 20 assessments by December 2022, although TSCA allows for a 6-month extension. The 20 chemicals include chlorinated solvents, phthalates, flame retardants, formaldehyde, a fragrance additive, and a substance used in polymers.

To the delight of the chemical industry, the EPA is allowing some exemptions on fees that companies are required to pay to fund the EPA’s assessment work. The exemptions apply to products that are imported or contain a chemical as an impurity, by-product, or intermediate. The agency is also being flexible with late payments during the COVID-19 pandemic.

"One of the 20 chemicals doesn’t have any companies listed” as responsible for paying fees.
Richard Denison, lead senior scientist, Environmental Defense Fund

The EPA chose not to impose fees for the first 10 chemicals and is still working out the kinks related to fees for the new set of 20. The Sept. 4 list of companies on the hook for paying fees for the 20 evaluations is much shorter than the initial list, released in January.

The American Chemistry Council, which represents US chemical manufacturers, stressed in a statement the importance of the EPA’s focusing “on the conditions of use that represent the greatest potential for risk.” The trade group is assisting the industry in forming consortia on certain substances to coordinate efforts related to risk evaluations and fees.

Environmental groups are concerned that the fees paid will fall short of the $1.35 million the EPA estimates it needs for each chemical. “One of the 20 chemicals doesn’t have any companies listed because all of them got exempted out,” says Richard Denison, a lead senior scientist at the Environmental Defense Fund (EDF). That chemical is the flame retardant tris(2-chloroethyl) phosphate, also known as TCEP.

The EPA’s rule on fees does not allow for exemptions, Denison says. To get around that, he notes, the agency decided not to enforce the part of the rule requiring companies to tell the EPA that they’re making a chemical that’s up for evaluation. The EPA plans to rewrite the rule later this year to allow for exemptions, he says.

The EDF and other environmental groups are disappointed that the EPA did not provide separate “systematic review documentation” for each of the 20 chemicals. Systematic review is used to identify the toxicity studies and other information considered in risk evaluations. Denison and others argue that the agency has been using flawed methodology in these reviews, resulting in evaluations that underestimate risks. The EPA’s systematic review process is “finally undergoing National Academy review after many, many delays on EPA’s part,” Denison says.

In addition to the work related to establishing fees and evaluating risks of chemicals, the EPA faces another big challenge this year under TSCA: developing proposed rules to mitigate the risks it found for methylene chloride and 1-bromopropane. If the agency finds risks associated with any of the other eight initial chemicals, it will also have to propose rules to mitigate those risks. The agency is required to propose rules within 1 year of identifying the risks and finalize the rules within 2 years, with the possibility of an extension.



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