Go to Top

DTSC Proposes New Priority Product: Spray Polyurethane Foam Systems with Unreacted MDIs

The California Department of Toxic Substances Control (DTSC) is seeking to add spray polyurethane foam systems containing unreacted methylene diphenyl diisocyanates (MDIs) to its list of Priority Products under the Safer Consumer Products Program. The comment period is open until May 16, 2017 and the submission form may be found here.

Safer Consumer Products Program

The Safer Consumer Products Regulations were promulgated in 2013 to establish a process to identify, prioritize, and evaluate substitutes for hazardous chemicals in consumer products. An informational list of these chemicals, termed “Candidate Chemicals” in the Safer Consumer Products Program and which are those deemed to present a hazard by various regulatory authorities, can be found here.

Priority Products are those that contain Candidate Chemicals and that are sold or manufactured within California. Only one other product/candidate chemical combination has been proposed as a Priority Product: children’s foam-padded sleeping products containing tris (1,3-dichloro-2-propyl) phosphate (TDCPP) or tris (2-chloroethyl) phosphate (TCEP). DTSC now is asking for public input on its proposal to add polyurethane foam systems containing unreacted MDIs to the Priority Products list. Once placed on the list, these systems will be required to undergo safer alternatives assessments to evaluate whether (1) the Candidate Chemicals are necessary to the product and (2) there is a safer alternative. Depending on the outcome of those assessments, DTSC is authorized to impose specified regulatory responses, such as labeling requirements, use restrictions or even bans.

Spray Polyurethane Foam Systems with Unreacted MDIs

DTSC defines the spray polyurethane systems proposed for listing as follows:

“spray polyurethane foam systems containing liquid chemical mixtures in two separate containers that are sold or distributed together. The two separate containers are commonly referred to as Side A and Side B. Side A contains unreacted methylene diphenyl diisocyanates. Side B contains a mixture of polyols and other ingredients which may include catalysts, blowing agents, flame retardants, and surfactants. The chemical mixtures in the sides react when mixed together to form polyurethane foam that is used for insulation, roofing, or sealing and filling voids and gaps.
This product-chemical combination includes:
(A) High-pressure spray polyurethane foam systems, and
(B) Low-pressure spray polyurethane foam systems.”

The specific candidate chemicals identified as the basis for the proposed listing are 4,4′-methylenediphenyl diisocyanate (Chemical Abstract Service Reference Number 101-68-8) and generic methylene diphenyl diisocyanate mixed isomers (Chemical Abstract Service Reference Number 26447-40-5).

As the proposed regulatory definition indicates, MDIs are often stored in products in an unreacted form before reacting with additional chemicals to create foams used in insulation, roofing, sealing and more. According to DTSC, unreacted MDIs are associated with asthma and allergic-sensitization and the agency’s move to include these spray polyurethane foam systems as a Priority Product is in response to evidence that consumers and workers may be exposed to the unreacted MDIs contained in them during normal use.

Nevertheless, at several stakeholder workshops in 2014 on DTSC’s draft Initial Priority Product List, which also included spray polyurethane foam systems with unreacted MDIs, business representatives strongly opposed the proposal, arguing that it was overbroad. These representatives also pointed out that these products already are highly regulated under state and federal law, rendering the proposal duplicative and unnecessary. Roofing contractors, an industry consisting of many small businesses, voiced their concern that the proposed listing would stigmatize the products — and their businesses. Many of these small business owners informed DTSC at the workshops that they already had lost business due to the proposed listing in the 2014 draft Initial Priority Product List. DTSC should expect these same complaints and concerns in the formal comments it is now eliciting.

Ann Grimaldi

About Ann Grimaldi

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.

Leave a Reply