tert-Butyl Alcohol (tBA)

CASRN 75-65-0

IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol or TBA) (Final Report)


EPA has finalized the IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol) [CASRN 75-65-0]. This assessment addresses the potential cancer and noncancer human health effects from exposure to tert-butanol or TBA. EPA’s program and regional offices may use this assessment to inform decisions to protect human health.


U.S. EPA. IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol or TBA) (Final Report). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-20/370F, 2021.

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tert-Butyl Alcohol (TBA) is used as a solvent; as a denaturant for ethanol and several other alcohols; in the manufacture of flotation agents, fruit essences, and perfumes; as an octane booster in gasoline; as a dehydrating agent; and as a chemical intermediate in the manufacture of methyl methacrylate. TBA's production for industrial uses may result in its direct release to the environment through various waste streams. TBA is also a likely degradation product of methyl tert-butyl ether (MTBE). Probable routes of human exposure to TBA include inhalation, ingestion, and skin or eye contact.


Date Description
01-Aug 2013EPA released preliminary assessment materials (draft literature searches and associated search strategies, evidence tables and exposure response arrays) for discussion at an IRIS Public Science Meeting.
02-Dec 2013EPA discussed tert-butanol at the December 2013 IRIS public science meeting.
03-Sep 2014EPA sent an interagency science consultation draft for review and comment.
04-May 2016EPA released the public comment draft for public review and comment.
05-Jun 2016EPA convened a public science meeting June 29-30, 2016 to discuss the public comment draft.
06-Jun 2017EPA released the external review draft and charge to reviewers prior to the public peer review meeting.[SAB FR Notice Jun 16, 2017]
07-Jul 2017EPA's Science Advisory Board (SAB) hosted a public teleconference to discuss the draft assessment.
08-Aug 2017EPA's SAB hosted a 2-day public meeting on August 15-17, 2017, to discuss the draft assessment.
09-Feb 2019EPA's SAB released a final report of their review of the draft IRIS assessment (see related links).
11-Jul 2020EPA submitted the revised interagency science discussion draft for final Agency and Interagency review.
12-Aug 2021EPA posted the final report IRIS Toxicological Review of Tert-Butyl Alcohol (tert-butanol) and released the interagency science discussion draft and comments to the IRIS database.

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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.

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