Skip to content

EPA Proposes SNUR for Toluene Diisocyanate

The U.S. Environmental Protection Agency has published a proposed Significant New Use Rule (SNUR) for 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, and toluene diisocyanate unspecified isomers (collectively referred to as “toluene diisocyanate” and “TDI”) under the federal Toxic Substances Control Act.  The proposed significant new use is any use in a consumer product, except for coatings, elastomers, adhesives, binders and sealants that result in 0.1%or less (by weight) of TDI in a consumer product.  This regulatory action follows EPA’s 2011 Chemical Action Plan for TDI, in which EPA explicitly considered a SNUR as a possible next step in TDI regulation.

Under TSCA Section 5, EPA may deem the use of an existing chemical substance as a “significant new use.” Section 5(a)(2) requires EPA to consider “all relevant factors” in making that determination, including the projected volume of manufacturing and processing of the substance and the extent to which the use increases the magnitude and duration of exposure to human beings or the environment. A SNUR for a chemical requires a manufacturer or processor of that chemical to give EPA 90 days’ notice before undertaking the use designated in the SNUR as a “significant new use.” The required notice, called a “Significant New Use Notice,” is functionally equivalent to a Pre-Manufacture Notice under TSCA. When EPA receives a SNUN, it may further regulate the chemical.  Ordinarily, persons who import and process the substance as part of an article are exempt; however, under the proposed SNUR for TDI, importers or processors of TDI as part of an article would not be exempt from the SNUR.

The industries identified as potentially affected by the proposed rule include paints, coatings and adhesives manufacturing, urethane and other foam product manufacturing, transportation polyurethane foam product manufacturing, and petroleum refining.


Ms. Grimaldi maintains a diverse environmental law practice focusing on chemical and product regulation and litigation defense. Her practice areas include Proposition 65, California's Safer Consumer Products Regulations, California's Rigid Plastic Packaging Container Act and the federal Toxic Substances Control Act. Ms. Grimaldi graduated from the University of California Hastings College of the Law magna cum laude and holds a Bachelor of Science Degree in Bacteriology from University of California, Davis. Prior to attending law school, she worked as a research assistant in laboratories at the University of California, San Francisco Cancer Research Institute and at the University of California, San Francisco School of Medicine.