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IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Interagency Science Discussion Draft, 2020)

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  • History
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Abstract

In August 2021, EPA finalized the IRIS assessment of ethyl tertiary butyl ether (ETBE). The Toxicological Review was reviewed internally by EPA and by other federal agencies and White House Offices after public release in June 2017. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science discussion materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Ethyl Tertiary Butyl Ether are posted on this site.
ETBE is used as a fuel additive for gasoline to increase octane rating and has been used to meet air pollution reduction goals in the U.S. under the Clean Air Act. The use of ether oxygenates such as ethyl tertiary butyl ether in reformulated gasoline in the United States was effectively eliminated in 2006; however, use and production of these oxygenates has continued in Europe and Asia for the purpose of increasing octane rating in gasoline. ETBE may be used as a substitute to replace the volume and oxygenate properties of methyl tertiary butyl ether, an oxygenate widely used in the United States prior to 2006. The main source of exposure to ETBE in U.S. is from exposure to contaminated groundwater due to leaking underground storage tanks.

Impact/Purpose

EPA is undertaking an new health assessment for ethyl tertiary butyl ether (ETBE) for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS Summary of ETBE that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used nationally and internationally in combination with specific situational exposure assessment information to evaluate potential public health risks associated with environmental contaminants. The IRIS database is relied on for the development of risk assessments, site-specific environmental decisions, and rule making.

Status

Now that the interagency review draft has been completed and finalized, the ETBE assessment has been loaded into the IRIS Web site and Database.

Citation

U.S. EPA. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Interagency Science Discussion Draft, 2020). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-20/106, 2020.

History/Chronology

Date Description
06- Aug 2013 EPA released preliminary assessment materials (e.g., literature searches and associated search strategies, evidence tables, and exposure response arrays) of ETBE for public discussion at the December 2013 IRIS Bimonthly Public Meeting.
07- Dec 2013 EPA convened public science meeting to discuss preliminary assessment materials.
08- Sep 2014 EPA submitted the draft assessments of ETBE for Interagency Science Consultation.
09- Sep 2016 EPA announced the availability of the draft assessment of ETBE for public comment and discussion and released the interagency science consultation draft, EPA response to select comments, and comments from reviewers. [Federal Register Notice Sep 1, 2016]
10- Oct 2016 EPA convened a public science meeting to discuss the public comment draft of the IRIS assessment of ETBE.
11- Jun 2017 EPA released the external review draft and charge to reviewers prior to the public peer review meeting.[SAB FR Notice Jun 16, 2017]
12- Jul 2017 EPA's SAB CAAC convenes to discuss the external review draft of the IRIS assessment.
13- Feb 2019 EPA's SAB released their review of the draft IRIS assessment.
14- Aug 2020 EPA submitted the revised interagency science discussion draft for final Agency and Interagency review.
15- Aug 2021 EPA posted the final report IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) and released the interagency science discussion draft and comments to the IRIS database.

Download(s)

This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.

  • IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Interagency Science Discussion Draft) (PDF)  (191  pp, 4.2 MB, about PDF)
  • IRIS Toxicological Review of Ethyl Tertiary Butyl Ether - Supplemental Information (Interagency Science Discussion Draft) (PDF)  (177  pp, 3.7 MB, about PDF)
  • EPA's Response to Major Science Comments (Interagency Science Discussion Draft) (PDF)  (2  pp, 150.4 KB, about PDF)
  • 1. CDC/NIOSH Comments on ETBE (PDF)  (3  pp, 124.0 KB, about PDF)
  • 2. OMB Comments on ETBE (PDF)  (1  pp, 118.2 KB, about PDF)

Related Link(s)

  • IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Interagency Science Consultation Draft, 2016)
  • IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Preliminary Assessment Materials, 2013)
  • IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Public Comment Draft, 2016)
  • IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft, 2017)
  • IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Final Report)
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Last updated on August 23, 2021
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