An EPA-issued draft risk evaluation of methylene chloride reports that the agency’s determination that the substance poses an unreasonable risk to workers, occupational non-users, consumers and bystanders under certain conditions. The risk evaluation was conducted under revised Toxic Substance Control Act (TSCA) regulations.

Methylene chloride, also known as dichloromethane (DCM), is a solvent with multiple manufacturing uses. These include paint removal and metal cleaning, chemical processing and pharmaceutical and flexible polyurethane foam manufacturing.

The EPA’s draft evaluation reveals that the substance poses serious central nervous system risks from acute exposures. Acute exposure can lead to incapacitation, loss of consciousness and death. Chronic exposure can cause liver and lung tumors and non-cancer liver effects.

In over 70 evaluated uses, the EPA found that methylene chloride presented an unreasonable risk. The highly risky applications ranged from import and disposal to over 30 industrial and commercial uses and two dozen consumer uses. Consumer use of products containing methylene chloride was banned in March 2019.

A few uses, including domestic manufacture, commercial distribution, industrial and commercial use as a laboratory chemical, were deemed acceptable.

What happens now?

The public can submit comments to the draft report through December 30, 2019. The Science Advisory Committee on Chemicals (Sacc) will conduct a peer review of the draft report December 3 and 4. Reviews must be completed by the end of December, with the possibility of a six-month extension. If the final report concludes that any potential uses create an unreasonable risk, the EPA must impose risk management measures to mitigate these concerns.

In the interim, the EPA strongly recommends that methylene chloride users follow product label instructions and use personal protective equipment as needed.