Methylene Chloride
The Environmental Protection Agency (EPA) recently evaluated methylene chloride under section 6(b) of the Toxic Substances Control Act and found that methylene chloride presents unreasonable risk of injury to health of potentially exposed persons and issued the Methylene Chloride; Regulation under Section 6(a) of the Toxic Substances Control Act (also known as the methylene chloride rule) that went into effect July 8, 2024.
Under this rule, the EPA allows limited and controlled continued use for research purposes with additional work protections. Environment, Health and Safety will be helping researchers adapt to this new ruling in the following ways:
- Performing initial exposure monitoring to determine exposure levels and notification of additional required work protections.
- Periodic monitoring to ensure levels remain below allowable concentrations.
- Assistance in removing methylene chloride from laboratory spaces through EHS Pick-Up Requests.
- Assistance with identifying solvent alternatives (see Other Resources).
Laboratories that choose to continue using methylene chloride will be required to take additional steps. Workers must undergo initial exposure monitoring and complete specific training on the use and handling of methylene chloride. Additionally, the lab safety plan must include a description of the use and handling of methylene chloride or include a Standard Operating Procedure (SOP) as an attachment.
- If you utilize methylene chloride, also known as dichloromethane, or DCM, within your laboratory, please ensure that it is listed in your chemical inventory. Please also check any biological kits that are utilized in your laboratory as some of these may contain DCM.
- If you currently have DCM in your laboratory, but do NOT use it, please submit an EHS pick-up request and remove it from your chemical inventory.
- If you are NOT using DCM for research purposes, (e.g., paint or paint stripper in arts), please submit an EHS pick-up request to remove DCM and any substituents containing DCM. Please utilize this list of DCM-containing products. Non-research use of DCM is not allowed under the new ruling.
| Goal Dates | Goal | EPA Timeline |
|---|---|---|
| August 2024– October 2024 |
Survey completed by all methylene chloride users | N/A |
| October 2024– March 2025 |
Completion of Initial Monitoring for all Laboratories that utilize methylene chloride | May 5, 2025 – Completion of Initial Monitoring of Existing Facilities (New Facilities within 30 days of initiating use). |
| January 2025– August 2025 |
Launch of Exposure Control Policy and methylene chloride training and ensure all users are aware and trained | August 1, 2025 – Exposure limits and Dermal Protections
October 30, 2025 – Exposure Control Plan/Policy |
The use of methylene chloride should follow specific policies and procedures based on your work environment. We are currently working on the Methylene Chloride Exposure Control Policy for more information on responsibilities and requirements. If you have questions regarding methylene chloride use or have not completed initial monitoring for exposure to methylene chloride, please contact Chemical Safety.
Other Resources
- OSHA 1910.1052 Methylene Chloride
- EPA Methylene Chloride; Regulation under Section 6(a) of the Toxic Substances Control Act
- EPA Compliance Guide: Regulation of Methylene Chloride under TSCA
- Alternative Solvent Recommendations and References
- Peptide Synthesis: 2-methyl tetrahydrofuran (2-MeTHF) or Ethyl acetate
- Extractions or Chromatography: Ethyl acetate, Heptane, Toluene, 2-MeTHF, Methyl tert-butyl ether
- Methylene Chloride (DCM) Replacements from Green Chemistry Teaching and Learning Community
Policies and Training
- Methylene Chloride Exposure Control Policy (Coming Soon)
- Methylene Chloride Online Training Course (Coming Soon)