Lindsay McCormick is a Project Manager.
Yesterday, EPA proposed a rule to ban methylene chloride and either ban or restrict the use of N-methylpyrrolidone in paint stripping products, subject to certain national security exemptions. This proposal is the third such proposed action by the agency in the past month (see here and here). Below, find a short description of these chemicals and EPA’s proposed actions.
Methylene chloride
Methylene chloride (also known as dichloromethane, or DCM) is carcinogenic, neurotoxic, and acutely lethal. It is produced and imported in huge amounts – 261 million pounds annually.
According to EPA, DCM’s short-term effects include “dizziness, incapacitation, and, in some cases, death.” As of 2012, OSHA had linked DCM to over 50 worker deaths nationwide since the mid-1980s. Many of these deaths have been associated with the use of DCM-based paint strippers in confined spaces to refurbish bathtubs. EPA’s 2014 risk assessment identified at least 15 such reported cases of worker deaths, associated with 10 different DCM-containing paint stripper products. Effects of long-term exposure to DCM include liver toxicity, liver cancer, and lung cancer.
EPA’s risk assessment demonstrated that current levels of exposure to DCM-containing paint strippers pose unacceptably high acute and chronic risks to workers and occupational bystanders as well as acute risks to consumers and residential bystanders.
Given these high risks, we applaud the Agency’s proposal to “prohibit manufacture (including import), processing, and distribution in commerce” for use as a paint stripper using its section 6 authority under the recently reformed Toxic Substances Control Act (TSCA). EPA’s current proposal does not, however, include commercial furniture refinishing, even though it has concluded that such uses present unreasonable risks; EPA notes it plans to issue a separate proposal after collecting more information on the impacts of regulating such uses to inform its selection of risk management actions.
N-methylpyrrolidone
NMP is commonly used as a DCM replacement, yet it too presents significant risks. Health impacts of NMP include developmental and reproductive toxicity, neurotoxicity, immunotoxicity, and liver and kidney toxicity. It is also produced and imported in large volumes (184 million pounds annually).
As we blogged about previously, EPA demonstrated in its 2014 NMP risk assessment that current levels of exposure to NMP-containing paint strippers pose an unacceptably high risk of adverse developmental toxicity (fetal effects) associated with acute and chronic exposure to female workers and consumers of childbearing age. EPA found that exposure to NMP-based paint strippers in women of childbearing age beyond four hours per day presents risks that cannot be mitigated from use of protective gear such as gloves and respirators.
In EPA’s proposed rule, it is requesting comment on two approaches to address risks of NMP. As stated in its press release:
One approach would prohibit manufacture (including import), processing, and distribution in commerce of NMP when used as a paint remover, as well as require various notification measures on the restrictions to downstream processors and users. The other approach would put in place a combination of requirements to address unreasonable risks, including limiting the amount of NMP in paint remover products [to 35% by weight], providing warning labels for consumers, and requiring workers to wear specialized gloves and other equipment.
EDF is very concerned about anything less than a ban on this use of NMP, given its demonstrated high risks and given that such labeling and protective equipment requirements are typically used already but are insufficient to mitigate the risks. In the proposed rule, EPA notes the limited effectiveness of labels, especially under real-world conditions. Further, reliance on personal protective equipment (PPE) is often subject to major practical limitations and at best mixed effectiveness. As recently described by OSHA:
…to be effective, respirators must be individually selected, fitted and periodically refitted, conscientiously and properly worn, regularly maintained, and replaced as necessary. The absence of any one of these conditions can reduce or eliminate the protection the respirator provides.
Respirator effectiveness ultimately relies on the practices of individual workers who must wear them. … Furthermore, respirators can impose substantial physiological burdens on workers, including the burden imposed by the weight of the respirator; increased breathing resistance during operation; limitations on auditory, visual, and olfactory sensations; and isolation from the workplace environment.
OSHA therefore continues to consider the use of respirators to be the least satisfactory approach to exposure control.
Addressing DCM and NMP simultaneously in a TSCA section 6 rulemaking makes a lot of sense. As NMP is a common substitute for DCM in paint strippers, this approach will help prevent regrettable substitution – where one bad chemical is simply replaced with another. However, this strategy will be severely hampered if the final rule relies only on NMP restrictions that fall short of a ban.
Putting aside the ample public health reasons to ban NMP for paint stripping uses, EPA’s economic analysis demonstrates that it would cost industry far more (on the order of $100 million) to implement such concentration, labeling, and PPE requirements than to comply with a simple ban.
EDF intends to submit comments on these aspects of the proposed rule, and encourages others to do the same. Comments will be accepted at www.regulations.gov (docket: EPA-HQ-OPPT-2016-0231) until 90 days after the rule’s publication in the Federal Register, which is expected next week.