US appeals court strikes down risk management rule for DCM

A US appeals court has struck down a key Environmental Protection Agency (EPA) rule banning all consumer and most industrial uses of the solvent dichloromethane (DCM), also known as methylene chloride (MC). The development comes after research labs across the country that routinely use the chemical – estimated to be in the thousands – have been working to comply with the agency’s now-cancelled DCM risk management rule for more than two years.

In a long-awaited decision on 15 September, the appeals court voided the DCM rule issued under former President Biden in 2024 and sent the matter back to the EPA. The regulation had mandated that federal and non-federal labs put in place DCM exposure monitoring by 9 November 2026 and meet stricter exposure limits by 8 February 2027.