Several solvents used in parts-cleaning operations — such as methylene chloride (MEC), perchloroethylene (perc), and trichloroethylene (TCE), and n-propyl bromide (nPB) — are all filed under “Risk Evaluation” by the U.S. EPA under the Toxic Substances Control Act (TSCA).
While some manufacturing facilities continue using nPB for vapor degreasing in parts cleaning operations, time may be running out for the use of those solvents as regulators at the federal and state level are beginning to look at banning or severely limiting those solvents’ uses. The EPA announced in 2016 that 10 chemicals — including methylene chloride, perc, TCE, and nPB — would undergo “Risk Evaluations,” the second step in EPA’s existing chemical process under TSCA.
The purpose of the evaluation is to determine whether a chemical substance presents an unreasonable risk to health or the environment under the conditions of use. As part of this process, EPA must evaluate both hazards and exposure, exclude consideration of costs or other non-risk factors, use scientific information and approaches in a manner that is consistent with the requirements in TSCA for the best available science, and ensure that decisions are based on the weight of scientific evidence.
