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Assessing and Managing Chemicals under TSCA

Risk Management for Toluene Diisocyanates (TDI)

What are toluene diisocyanates?

Diisocyanates (also commonly known as isocyanates) are highly reactive and versatile chemicals with widespread commercial and consumer use.

The Toluene Diisocyanates (TDI) Action Plan (PDF) addresses EPA’s review of Toluene Diisocyanate (TDI) and related compounds, CASRNs 91-08-7, 584-84-9, 26471-62-5, 9017-01-0, 26747-90-0, and 26603-40-7.

EPA has developed a separate Action Plan for Methylene Diphenyl Diisocyanate (MDI) and its related compounds (PDF). TDI is chemically similar to MDI and presents similar hazard and exposure concerns, but is reportedly used in a different range of products.

Why is EPA concerned?

Diisocyanates are well known dermal and inhalation sensitizers in the workplace and have been documented to cause asthma, lung damage, and in severe cases, death. Worker exposures are already subject to protective controls in occupational settings, but EPA is concerned about potential health effects that may result from exposures to the consumer or self-employed worker while using products containing uncured TDI and its related polyisocyanates (e.g., spray-applied sealants and coatings) or incidental exposures to the general population while such products are used in or around buildings including homes or schools.

What action is EPA taking?

  • January 8, 2015: EPA proposed a Significant New Use Rule (SNUR) under the Toxic Substances Control Act (TSCA) for consumer uses of seven TDIs.

    The proposed SNUR would give EPA the opportunity to evaluate and if necessary, to take action to prohibit or limit new or resumed use of the chemicals at greater than 0.1% in coatings, adhesives, elastomers, binders, and sealants in consumer products including imported consumer products. For all other uses in consumer products, EPA would have the opportunity to evaluate a new or resumed use of the chemicals at any level. EPA will accept public comments on the proposed rule for 60 days.

Previous actions