Jump to main content.


Methylene Diphenyl Diisocyanate (MDI) and Related Compounds Action Plan Summary

What chemicals are addressed in the action plan?

This action plan addresses EPA’s review of Methylene Diphenyl Diisocyanate (MDI) and related compounds, CASRNs 101-68-8, 5873-54-1, 2536-05-2, 26447-40-5, 9016-87-9, 17589-24-1, 31107-36-5, and 25686-28-6.

EPA has developed a separate Action Plan for Toluene Diiscyanate (TDI) and its related compounds. 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 about these chemicals?

Diisocyanates are well known dermal and inhalation sensitizers in the workplace and have been documented to cause asthma, lung damage, and in severe cases, fatal reactions. 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 (unreacted) MDI and its related polyisocyanates (e.g., spray-applied foam sealants, adhesives, 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?

Based on EPA’s screening-level review of hazard and exposure information, including information indicating uncured MDI and its related polyisocyanates are used in a range of consumer and commercial products as well as in products intended only for an industrial market, EPA intends to:

Previous Actions:

Read about the ongoing federal partnership activities for safer use of spray polyurethane foam containing MDI and related compounds.

Current Actions:

Download the complete Methylene Diphenyl Diisocyanate (MDI) Action Plan (PDF), (16 pp., 67 KB, About PDF)

Access the public comment docket for the Methylene Diphenyl Diisocyanate (MDI) Action Plan (Docket ID EPA-HQ-OPPT-2011-0182) on Regulations.gov.


Local Navigation


Jump to main content.