EPA Targets Diisocyanates

Diisocyantes, which are ingredients in polyurethane plastics, face Environmental Protection Agency regulation due to concerns about health effects, the agency announced on April 13.

The main focus of EPA's efforts is do-it-yourself consumer products such as spray foam insulation, concrete sealers, adhesives, and floor finishes. These polyurethane products may contain uncured diisocyanates, according to the agency. This contrasts with cured products, such as polyurethane foam in mattresses, which are not of concern, EPA says.

Diisocyantes can cause breathing and skin problems, the agency says. The Occupational Safety & Health Administration limits exposure to diisocyanates in the workplace. These chemicals are the leading cause of work-related asthma.

Consumer exposure to the substances, however, is unregulated.

"There has been an increase in recent years in promoting the use of foams and sealants by do-it-yourself energy-conscious homeowners, says Steven Owens, EPA assistant administrator for chemical safety & pollution prevention. "Many people may now be unknowingly exposed to risks from these chemicals."

The agency is taking a two-fold approach to diisocyanates. One is to target toluene diisocyanate (TDI) and related compounds. The other aims at methylene diphenyl diisocyanate (MDI) and similar chemicals: MDI monomers and related isomers and polymers; and MDI dimers, trimers, and polymers.

EPA intends to issue a rule under the Toxic Substances Control Act to require companies to notify the agency before using uncured TDI and related polyisocyanates in consumer goods. The agency says it will also consider working with industry on a voluntary phase-out of these uses of TDI. If it can't strike a deal with the private sector, EPA says it will consider regulation to require makers of TDI and related chemicals to monitor exposure to the compound in consumer goods.

The agency plans to ask manufacturers of both TDI and MID to report any allegations of significant adverse effects from exposure to these chemicals. The agency will also require these companies to submit any unpublished health and safety data they have on these compounds.

Also, EPA will consider regulations to require makers of these compounds to conduct exposure monitoring studies for commercial products with uncured TDI and MDI. The agency said it may regulate commercial uses of products in locations where the general public might be exposed to TDI and MDI. Plus, EPA will consider regulating consumer products containing uncured MDI.

"We look forward to a productive exchange with EPA on the action plans," says Kathryn St. John, spokesperson for the American Chemistry Council (ACC), an association of chemical manufacturers. "Working with EPA over many months, we have enhanced product stewardship programs to further improve safe use of spray polyurethane foam."

In 2009, The Center for the Polyurethanes Industry, which is part of ACC, and the Spray Polyurethane Foam Alliance in 2009 launched a product stewardship program for safe use and handling. The groups also have a Web site on spray polyurethane foam insulation and insulating foam sealants providing health and safety information for contractors, do-it-yourselfers, and homeowners.

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