Trichloroethene, or TCE, is a chemical solvent that has historically been widely used by the metals manufacturing industry as a degreaser. TCE is also used in industrial and household goods like adhesives, paint and stain removers, and finishing products. But, following a bill signing by Governor Tim Walz on May 16, TCE’s use in the State of Minnesota will come to a halt. This following the Minnesota House’s 117-17 vote on May 13th and the Minnesota Senate’s 66-1 vote on April 30th to pass a bill banning the chemical’s use.
TCE is a volatile carcinogen that, at certain concentrations, is odorless and undetectable by human senses. When inhaled at high enough levels, TCE can cause damage to immune and reproductive systems, damage to internal organs, and can affect fetal development. After it was discovered that Minnesota manufacturers were emitting tons of TCE emissions into the air for a number of years, the Minnesota Pollution Control Agency (MPCA) issued an update in January 2020 that may have spelled the beginning of the end for TCE in Minnesota. The MPCA reviewed 86 facilities in the State; 26 that used TCE in industrial processes and 60 that generated TCE as a combustion byproduct. Based on modelling conducted by the MPCA, eight of these facilities were found to be emitting TCE above the Health Based Value (HBV) for the chemical even though they were in compliance with their issued permits. The MPCA worked with several of these facilities to reduce their emissions or to transition their operations to a different solvent, which resulted in the removal of 174,150 pounds of TCE emissions. In addition to air emissions concerns, TCE is also a contaminant which impacts soil and groundwater when released to the environment and can also be a primary concern when buildings overlie that contamination from a vapor intrusion perspective.
The use of TCE has already been widely banned in the European Union and although its use has diminished in the United States since the discovering of its hazards in the 1970s, the passing of this bill will make Minnesota the first state to outlaw its use. Put succinctly by MPCA Assistant Commission Craig McDonnel in an interview with the Star Tribune, “We want to get it out of the system.”
Minnesota companies will have until June 2022, when the ban goes into effect, to find alternative chemicals to use or make modification to their processes. The University of Minnesota’s School of Public Health’s Minnesota Technical Assistance Program (MnTAP) is in the midst of the USEPA- and MPCA-funded “TCE Alternatives Project”, which runs from February 2019 to September 2020. The purpose of the TCE Alternative Project is to “focus on replacing TCE with safer, yet effective options.” Through their partnership with the Toxic Use Reduction Institute (TURI) at the University of Massachusetts Lowell, MnTAP has established an advisory and training program to assist Minnesota-based companies in making the transition away from TCE. And while MnTAP admits that there is “no silver bullet when it comes to replacing TCE in cleaning operations”, there are a number of alternative options, including other halogenated solvents, non-halogenated solvents, aqueous cleaners, or process changes.
Minnesota-based companies have some time to research and manage the transition away from TCE, but the passing of this bill could signal a broader end to TCE’s use in the United States. Manufacturers in Minnesota and around the country should work with their environmental team to determine if using TCE will become too great a liability for their organization, and what the best route may be to adjust for the future.
It should be noted that legacy liability issues associated with historical TCE use (as well as products that degrade to produce TCE as a degradation bi-product such as tetrachloroethene (PCE)) will continue to exist likely for years to come.