EPA seeks limits on NMP use

Continuing to take action on 10 potentially harmful chemicals it is evaluating under revisions to the Toxic Substances Control Act (TSCA), the US Environmental Protection Agency says it is seeking new limits on the use of the solvent N-methylpyrrolidone (NMP).

In a May 5 proposal, the agency says it wants to ban the use of NMP in auto care, cleaning and degreasing, metal, and cleaning and furniture-care products. The EPA proposes to limit NMP concentration to 45% in glues and adhesives. And it is proposing a workplace protection program to prevent direct skin contact with NMP in industries like semiconductor and lithium-ion battery manufacturing that continue to use the solvent.

“We’re making great strides in our efforts to protect people’s health from exposure to chemicals like NMP,” Michal Freedhoff, assistant administrator for the EPA’s Office of Chemical Safety and Pollution Prevention, says in a press release announcing the proposal. “Our proposed commonsense worker protections would keep people safe while also ensuring that NMP could continue to be used, as needed.”

NMP is 1 of the initial 10 chemicals the EPA targeted in 2016 for potential limitations on use. It later added 20 more chemicals to the list. In April, the EPA finalized a ban on most uses of 1 of the 10, the solvent methylene chloride. And in March, it banned chrysotile asbestos, the last type of asbestos still used in the US, mainly in diaphragms found in plants that make chlorine and caustic soda.

Unlike methylene chloride and asbestos, though, NMP is a necessary solvent in some industries, the EPA acknowledges. The agency says it expects that sectors like chip- and battery-making have already implemented exposure controls of the type that it would require. In other industries, including paints, adhesives, and inks, the EPA proposes controls such as concentration limits and the use of personal protective equipment.

In 2020 the agency concluded that NMP-based paint strippers are not a risk to consumers, and indeed, the proposed rule doesn’t contain limits on such products. The solvent was once touted as a safer alternative to methylene chloride in paint strippers, but major retailers like Home Depot, Lowe’s, and Walmart dropped both kinds of strippers several years ago.