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US EPA lawsuit targets Denka’s neoprene plant

Agency claims chloroprene emissions pose cancer risks for people living near the Louisiana facility

by Britt E. Erickson
March 1, 2023 | A version of this story appeared in Volume 101, Issue 8


The neoprene maker Denka Performance Elastomer is facing a lawsuit from the US government over chloroprene emissions from the company’s plant in LaPlace, Louisiana.

The chemical structure of chloroprene.

In a complaint filed Feb. 28, the Environmental Protection Agency claims that people living near the facility “are being exposed to an unacceptably high risk of developing certain cancers because of Denka’s chloroprene emissions.” The agency, which has been monitoring the facility since 2016, wants the court to force the company to reduce emissions.

Denka argues that the EPA’s risk assessment, conducted in 2010 by the agency’s Integrated Risk Information System, overpredicts the cancer risk from chloroprene by 130 times. The company plans to formally ask the EPA to incorporate a newer model into that assessment.

Denka purchased the LaPlace facility in late 2014 from DuPont. Since then, Denka says, it has spent over $35 million to upgrade its emission reduction systems, including installing a regenerative thermal oxidizer.

DuPont introduced neoprene in 1931. Today the tough, chemically resistant rubber is used to make hoses, gaskets, wet suits, laptop sleeves, and other products. It is produced by polymerizing chloroprene.

The EPA classifies chloroprene as likely to be carcinogenic. Air monitoring conducted by the agency and Denka shows that average concentrations of chloroprene near the LaPlace facility are consistently more than 14 times the recommended levels, according to the EPA. The increased cancer risk “presents an imminent and substantial endangerment to public health and welfare,” the complaint asserts. Infants and children are especially vulnerable, the EPA says.

In late 2021, EPA administrator Michael S. Regan visited a community adjacent to the Denka facility as part of an effort to address environmental justice issues. “The company has not moved far enough or fast enough to reduce emissions or ensure the safety of the surrounding community,” Regan says in a statement announcing the lawsuit. “This action is not the first step we have taken to reduce risks to the people living in Saint John the Baptist Parish, and it will not be the last.”



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