NMP poses low risk to consumers, US EPA says

Armed with new toxicity data provided by chemical manufacturers, the US Environmental Protection Agency claims that the solvent n-methylpyrrolidone (NMP) does not pose unreasonable health risks to consumers who use it to remove paints and coatings. The agency previously found that such uses of NMP increase the risk of miscarriage in pregnant women.

The final assessment, released Dec. 23, finds unreasonable risks for only one consumer use of NMP—in adhesives and sealants in glues. It also finds more than two dozen commercial uses of the solvent pose unreasonable risks to workers. Risks to workers are typically linked to chronic exposures, whereas risks for consumers are associated with acute exposures, the agency says. Chronic exposure to NMP can lead to reduced fertility. Acute exposure can cause miscarriages.

NMP is commonly used in manufacturing chemicals, processing petrochemicals, and cleaning and degreasing electronics. It is also widely used in making semiconductors and lithium-ion batteries. The solvent was once touted as a safer alternative to methylene chloride in paint removers, until the EPA raised concerns in 2015 about reproductive risks to pregnant women and women of childbearing age.

During the final days of the Obama administration, the EPA proposed to ban or restrict NMP in paint removers. The agency never finalized that proposal. Instead, in late 2017, the Trump administration opted to evaluate the risks of a broader swath of NMP uses under 2016 amendments to the Toxic Substances Control Act. The latest assessment is the result of that effort.

Environmental groups are questioning the legality of the EPA’s approach. In August 2020, a coalition of groups sent a letter to the agency, asking for an opportunity to comment on the studies provided by NMP producers. The EPA made those studies public after the comment period for the draft assessment closed and after its group of external advisors peer reviewed the draft assessment. Nevertheless, the agency used data from those studies to revise and finalize the assessment, concluding that acute exposures to NMP in most cases do not pose unreasonable health risks to consumers.

The EPA will propose regulations to minimize the risks of NMP identified in the final assessment within one year. In the meantime, the agency recommends the use of personal protective equipment, including chemical-resistant gloves, when handling NMP.