Jennifer McPartland, Ph.D., is a Senior Scientist with the Health Program.
The Environmental Protection Agency (EPA) took another significant step yesterday to protect against exposures to the highly toxic chemical, trichloroethylene (TCE), proposing a rule to ban its use as a vapor degreaser.
The proposed rule is the second issued under section 6 of the Toxic Substances Control Act (TSCA) as amended by last year’s Lautenberg Act. It follows on EPA’s proposed rule last month to ban the use of TCE as an aerosol degreaser and spot cleaning agent in dry cleaning facilities. Both proposed rules on TCE are critical to protecting consumer and worker health from the harmful effects of TCE and should move swiftly toward finalization.
TCE is a volatile organic compound, produced in huge volumes (255 million pounds in the US). It is highly toxic, with identified health effects ranging from skin and eye irritation and dizziness to cardiac malformations in the developing fetus and cancer. TCE is fat-soluble, easily crosses biological membranes, and has been detected in breast milk and maternal and fetal blood.
In vapor degreasing TCE is boiled in a degreasing unit, creating a hot vapor that upon contact with fabricated parts, condenses and absorbs and carries contaminants away. Vapor degreasing is conducted in many settings, such as electronics assembly and repair shops. EPA’s 2014 risk assessment of TCE found that current levels of exposure to the chemical from its use as a vapor degreaser pose unacceptably high levels of risk to workers and occupational bystanders.
The proposed ban on TCE’s use as a vapor degreaser would eliminate those risks and provide for healthier workplaces.
More specifically, EPA’s proposed rule:
- prohibits the manufacture (including import), processing, and distribution in commerce of TCE for use in vapor degreasing;
- prohibits commercial use of TCE in vapor degreasing; and
- requires manufacturers, processors, and distributors except for retailers, to provide notification of this prohibition throughout the supply chain and to keep records.
Notably, EPA estimates the proposed rule would result in monetized benefits ranging from $65 to $443 million at a 3% discount rate on an annualized basis over 20 years based on reductions in cancer risks alone. The agency did not have sufficient information to additionally quantify the benefits of the non-cancer health impacts.
Lest anyone think that the Occupational Safety and Health Administration (OSHA) has adequate workplace standards to mitigate such risks, think again: OSHA’s permissible exposure limit (PEL) for TCE was set way back in 1971. OSHA acknowledges that many of its PELs, including that for TCE, are not protective of worker health. It has noted that:
“with few exceptions, OSHA’s PELs, which specify the amount of a particular chemical substance allowed in workplace air, have not been updated since they were established in 1971 under expedited procedures available in the short period after the OSH Act’s adoption…Yet, in many instances, scientific evidence has accumulated suggesting that the current limits are not sufficiently protective.”
EPA’s proposed rule to eliminate the use of TCE in vapor degreasing is supported by strong science as necessary to protect the health of workers—a subpopulation specifically called out in the Lautenberg Act as “potentially exposed or susceptible” and required to be considered and protected in all chemical risk evaluation and risk management decisions.