Denka provides update on US chloroprene rubber legal cases

Tokyo – Denka Inc. is facing 20 ongoing legal cases involving a “cumulative total” of 7,308 plaintiffs over alleged emissions from its US chloroprene rubber (CR) subsidiary, Denka Performance Elastomer (DPE).

In its recently published 2026 integrated report, Denka said the cases had been filed against DPE, in which it holds a 70% stake, as well as previous owner DuPont and related companies.

The lawsuits have been filed since 2018 in the 40th Judicial District Court in Louisiana, with 20 cases remaining pending as of the end of March, Denka said.

The plaintiffs, said the Japanese group, “allege that they suffered physical, property and mental damages as a result of chloroprene monomer emitted from a chloroprene rubber manufacturing plant located in Louisiana.”

The facility began operations under DuPont in 1969 and was acquired by DPE from DuPont in November 2015.

According to Denka, the plaintiffs are seeking damages from DPE and DuPont of “no more than $50,000 per plaintiff.”

“DPE intends to continue responding appropriately through the litigation proceedings,” the group said.

Separately, Denka provided an update on DPE's legal challenges concerning US Environmental Protection Agency (EPA) emissions regulations for chloroprene rubber manufacturing facilities.

The EPA announced the new regulations in April 2024, requiring US CR plants to implement various emissions-control measures and significantly reduce emissions of chloroprene monomer.

DPE filed a petition with the US Court of Appeals for the District of Columbia Circuit in May 2024, seeking a review of the regulations.

It subsequently filed a second petition with the US Court of Appeals for the Fifth Circuit in July 2024, seeking confirmation of the legal validity of the Louisiana Department of Environmental Quality's decision to grant a two-year extension to the regulations' compliance period. (ERJ report)

“Both cases remain pending before the respective courts; however, as of the date of submission, proceedings have been stayed by decisions of the respective courts,” Denka said.