IRIS Toxicological Review of Chloroprene (Final Report)

The final Toxicological Review of Chloroprene provides scientific support and rationale for the hazard and dose-response assessment pertaining to chronic exposure to chloroprene. Chloroprene (C4H5Cl) is a volatile, flammable liquid used primarily in the manufacture of polychloroprene or neoprene rubber. The latter is used to make diverse products, such as tires, wire coatings, and tubing. Human health risk concerns for chloroprene are primarily related to exposures via effluent and emissions from facilities that use chloroprene to produce polychloroprene elastomers or transport the product, although these exposure concerns have not been well characterized.

This assessment contains the derivation of a chronic inhalation reference concentration (RfC) and chronic cancer inhalation unit risk.


Chloroprene (CASRN 126-99-8) or 2-chloro-1,3-butadiene is a volatile liquid monomer used exclusively in the manufacture of polychloroprene (neoprene) elastomer.


U.S. EPA. IRIS Toxicological Review of Chloroprene (Final Report). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-09/010F, 2010.


Date Description
01-1999The IRIS reassessment of chloroprene was initiated in 1999. Currently there is no entry in the IRIS database for chloroprene.
02-Sep 2009EPA released the external review draft for public review and comment.
03-Nov 2009EPA announced the public listening session to be held on November 23, 2009 in a November 5, 2009 Federal Register Notice.
04-Dec 2009EPA announced an external peer review workshop to be held on January 6, 2010 in a December 1, 2009 Federal Register Notice.
05-Feb 2010EPA released the comments from the public comment period and external review workshop.
06-Jul 2010EPA hosted an interagency science discussion on the review of the draft Toxicological Review of Chloroprene.
07-Sep 2010EPA released the final toxicological report and IRIS Summary for Chloroprene and the interagency science discussion draft with comments.

This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.