The Environmental Health, Safety, and Sustainability department is planning for the implementation of the Environmental Protection Agency’s new rule regulating the use of dichloromethane/methylene chloride (DCM/MC). The new regulation does not ban the use of DCM/MC in research, nor does Vanderbilt have any intention to ban its use, but it does significantly increase the regulatory requirements for its use. Academic research laboratories must comply with these new requirements. More info about this new rule is available here.
The current DCM/MC compliance timeline provided by the EPA is as follows:
- By May 5, 2025, we must complete initial air monitoring/sampling of “potentially exposed persons” user groups. This will require sampling the air in a person’s breathing zone of a representative sampling of individuals who use large amounts of DCM/MC (high-level users) and those who use small quantities (low-level users). If any sampling results are at or above the level established in the rule, then periodic air sampling is required for that person or user group (depending on the pervasiveness of sampling results exceeding limits) on either a 3-month or 6-month frequency.
- By August 1, 2025, no individual at Vanderbilt can be exposed above the very conservative limits set by the EPA.
- By October 30, 2025, VU must establish a Workplace Chemical Protection Program (WCPP) involving additional training, PPE, and documentation requirements for anyone continuing to use DCM/MC.
NOTE: On May 27, EPA proposed extending the above deadlines to the following dates:
- To November 9, 2026, for completion of initial monitoring.
- To February 9, 2027, for compliance with exposure limits.
- To May 10, 2027, for implementation of an Exposure Control Plan (ECP).
The proposed rule is currently in the public comment period which ends on June 26, 2025, and can be found here.
At this time the least impactful course of action for VU labs is to find substitutes if at all possible and subsequently dispose of any DCM/MC currently in stock by notifying us by requesting a waste collection through EHS Assist; however, we recognize that substitution might not be possible in your lab’s processes and we will strive to support you in incorporating these new requirements into your lab’s operations in the least impactful way possible. Only mixtures/products that include DMC/MC below 0.1% by weight are NOT subject to the restrictions in this regulation.
While there are lab processes that will continue to require the use of DCM/MC, suggested chemical substitutions are summarized below. If you have other suggestions, please email us at chemicalsafety@vanderbilt.edu and we will add them to the list.
Chromatography and extraction are good targets for substitution because they are two of the most common and high-volume laboratory tasks where DCM/MC is used.
- ACS Green Chemistry Institute has published resources on dichloromethane alternatives – See “DCM Alternatives & Resources” at acs.org/dcm
- In a 2008 article in Green Chemistry, the Environmental, Health and Safety (EHS) group at Pfizer Global Research and Development recommended replacing methylene chloride with Ethyl Acetate/Hexane for chromatography and with Ethyl Acetate, MTBE, Toluene, or 2-MeTHF for extractions.
- Teledyne ISCO suggests a 3:1 ratio of ethyl acetate to ethanol as a starting point for creating new methods without DCM for chromatography purification.
If you would like to dispose of the DCM/MC in your lab, then please submit a waste collection request in EHS Assist.
Our office will provide more specific support to the labs who will need to continue to use DCM/MC to help you come into compliance before the initial regulatory deadline. Please email chemicalsafety@vanderbilt.edu with any questions. We greatly appreciate your cooperation and collaboration with this new requirement.