An ad hoc committee of the National Academies of Sciences, Engineering, and Medicine will review the scientific and technical bases of DOD's approach to developing an occupational exposure level (OEL) for trichloroethylene (TCE), including for workplace settings in which vapor intrusion is the pathway of exposure. The committee will include consideration of these specific questions:

• Did the Army generally follow the recommendations of the 2019 NAS report, “Review of DOD's Approach to Deriving an Occupational Exposure Limit for Trichloroethylene,” including

• Developing a narrative protocol for performing toxicological assessments to support derivation of an OEL for TCE;

• Synthesizing evidence from animal, human, and mechanistic studies adequately, followed by the evidence integration methods described by Lent et al. (2021) [International Journal of Toxicology 2021, Vol. 40(2) 178-195] to identify main hazards; and

• Evaluating evidence of cancer risk

• Did the article by Lent et al. (2021) entitled: “Using Evidence Integration Techniques in the Development of Health-Based Occupational Exposure Levels” satisfy the recommendations of the 2019 NAS report for a published narrative method for OEL derivation? Were the guidelines in Lent et al. 2021 generally followed in developing the TCE OEL?

• Does the revised DoD TCE Technical Report (revision 1) clearly and transparently follow the approach recommended from Lent et al. (2021) to derive an OEL?