Be brave! Read about developments at the EPA. It will be fun – sort of. Welcome to the giant multi-dimensional Sudoku puzzle in the sky. Regulations, both safety and environmental, are so complex and fluid that they result in a monumental headache for manufacturers. Two EPA developments may result in the availability of new and established cleaning agents and therefore can affect your cleaning process, your product quality, and your profitability. I have simplified the discussion so as not to drive you to distraction. If you want to talk about how these changes might impact you, give me a call.
One development is EPA prioritization of the timeline at which existing chemicals are regulated under the Toxic Substance Control Act (TSCA). The second is a court ruling that would change the scope of authority of the EPA Significant New Alternatives Policy (SNAP) program.
TSCA, Existing Chemicals
In 2016, TSCA was amended by the “Frank R. Lautenberg Chemical Safety for the 21st Century Act.” This Federal legislation impels the EPA to prioritize, evaluate, and if necessary regulate or even ban chemicals that are considered toxic. Of the initial list of 10 chemicals for near-term evaluation five are used for cleaning in manufacturing. These include trichloroethylene (TCE), perchloroethylene (tetrachloroethylene), methylene chloride, n-propyl bromide (1-bromopropane), and n-methylpyrrolidone (NMP).
Because risk assessment and risk management were further along for TCE, in 2017 EPA proposals included a ban on TCE not only in emissive applications like aerosols but also in vapor degreasing. The resulting comments manufacturers and environmental groups were, shall we say, spirited. There were proclamations that “the end is near” – some declared the end of aggressive cleaning agents, others forecast the end of effective manufacturing. While the EPA evaluation process remains in place, the timeline has stretched out, eliciting comments that the EPA is “shelving” proposals to expunge “bad, toxic chemicals.”
The EPA has moved the evaluation of the initial list of 10 chemicals, including trichloroethylene, to “long-term actions” (1). The EPA has 3 to 3 ½ years to evaluate the first ten chemicals that were selected in December 2016. So, for example, for perchloroethylene, this brings the due date for the risk evaluation to as late as June 2020. Because the EPA has two years to take final risk management action and because there could be an extension of up to two years, risk management rules could be happen between December 2021 and December 2023. The summary for the evaluation process is available (2).
For any given chemical, we have to consider other EPA activities. For example, n-propyl bromide is a long-term action in the TSCA group. There is a petition to add n-propyl bromide to the list of hazardous air pollutants (3), and that action is moving along more rapidly, with an notice date of September 2018.
The EPA SNAP program covers substitutes for ODCs (Ozone Depleting Chemicals). Last summer, a U.S. District Court ruled that EPA SNAP could rule on substitutes for ODCs only, not on subsequent generational process changes. I think some people may have missed the significance of the ruling, because the immediate issues in the lawsuit are for refrigerants, not cleaning solvents, and relate to climate change.
Since the 1990s, SNAP has looked at substitutes for ODCs in specific sectors, including various types of cleaning processes and aerosols. A quarter of a century or so after SNAP began, essentially all manufacturers use something other than ODCs for cleaning. However, if the manufacturing sector ever used an ODC, then new chemicals have to be reviewed by SNAP; and SNAP could restrict the use of a new chemical or even declare it to be unacceptable. Let’s say, for example, that a company used CFC-113 (remember Freon 113?). Then, beginning in the 1990’s they switched to a series of new and exciting chemicals – first they used a cleaning process with Chemical A, then one with Chemical B, then Chemical C. Each of those chemicals have to be reviewed by SNAP. And, in addition to the impact on the upper ozone, SNAP considers global warming, toxicity, and tropospheric reactivity (ability to impact the lower ozone layer, to make smog). Further, some substitutes have been used for product cleaning for decades while the EPA decides on a final ruling about acceptability.
In the refrigerants issue, EPA SNAP phased out HFC refrigerants because while they are not ODCs, they do have a relatively long atmospheric lifetime. This EPA position is consistent with global agreements and by the corporate policies of many multinational manufacturers. The lawsuit was actually opposed and appealed by some HFCs manufacturers. This is not as counterintuitive as might first seem. The chemical manufacturers had invested considerable effort financial resources to develop HFC substitutes with short atmospheric lifetimes for both U.S. and international markets. The ruling is to be appealed to the Supreme Court (6), but only a small percentage of cases that are appealed are actually heard.
What does this mean for critical product cleaning?
Many of those in the environmental community would like to see all “bad” solvents banned. Manufacturers of what are currently considered to be green cleaning agents would like to see all “bad” solvents banned. In terms of TSCA review of existing chemicals, delaying evaluation, including risk assessment, is likely to escalate anger on all sides. If a slower evaluation allows more truly scientific evaluation, there could be a benefit. However, a slower evaluation that focuses on the chemical alone to the exclusion of the cleaning process could discourage the development and adoption of more effective, well-contained cleaning systems.
On one hand, without the SNAP process, could there could be more solvent options for parts cleaning? Maybe. Other groups within the EPA could take over what are now SNAP activities – but this shuffling results in uncertainty. Why would a chemical supplier spend money to develop substitutes in an uncertain regulatory landscape? The continued uncertainty could make those who synthesize chemicals even more reluctant than they are now to spend money on developing new refrigerants and solvents.
TSCA considers unreasonable risk. Initial estimates of allowable exposure for trichloroethylene indicated that control was not possible. I would suggest that the EPA re-evaluate their determinations and consider carefully the methods and assumptions that are behind those determinations. If you have 10 apples to be divided among 5 children, each child gets half an apple. That’s a calculation. With toxicity studies, there is more uncertainty; and long division alone is not the answer Consider the variables in animal studies. Toxicologists are not dividing apples among children. They are not doing calculations; they are doing extrapolations. We need to look at those extrapolations critically.
We also need to look at the potential utility of each chemical- the good and the bad. In looking at leachable residue of medical devices, risks and benefits are both considered. We have to do the same for solvents. Is the solvent essential for cleaning high-value parts? Are there really substitutes? For many critical processes there may not be.
“Green” Chemistry and Solvent Substitution
I myself am often asked how I feel about green chemistry, aggressive (perhaps toxic) chemicals, and solvent substitution. I am opposed to solvent bans. I don’t see chemicals as inherently green or not green. It depends on the process. With rare exceptions, most chemicals can be used safely with the proper process controls.
I am opposed to solvent bans on general principles. Starting the late 1980’s, I was actively involved in the phaseout of ozone depleting compounds, and I developed and tested substitute cleaning processes for critical applications. I am a proud recipient of a U.S. EPA Stratospheric Ozone Protection Award for my activities. However, solvent substitution was not and still is not the answer. The replacement processes all had other safety and/or environmental baggage. It’s not the chemical – it’s the process. Nearly all chemicals can be used safely, with appropriate controls. Even so called ‘green’ chemicals can be used unsafely. We need to start looking at the pros and cons of any chemical. Aggressive chemicals are often needed to achieve good surface quality; and if the chemical is aggressive to surface soils, it can also be aggressive to life forms (including people).
(1) “Agency Rule List – Fall 2017”
(2) “Risk Evaluations for Existing Chemicals Under TSCA”
(3) “Petition to Add n-Propyl Bromide to the List of Hazardous Air Pollutants”
(4) S.A. Millar et al. J.C. Walker, and N.A. Cardon, “D.C. Court’s Mexichem Decision May Alter SNAP Dramatically,” The National Law Review, August 14, 2017
(5) “Honeywell turns to Supreme Court to defend EPA HFC ruling.” RAC, February 6, 2018