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Ethyl Tertiary Butyl Ether (ETBE)

CASRN 637-92-3 | DTXSID0025604

  • Toxicological Review (PDF) (200 pp, 4.29 M)
  • IRIS Executive Summary (PDF) (8 pp, 298 K)
  • Supplemental Information on the IRIS Toxicological Review of Ethyl Tertiary Butyl Ether

On this page:

  • Key IRIS
    Values
  • Chemical
    Documents
  • Other EPA
    Information

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (8 pp, 298 K) Last Updated: 08/13/2021

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Urinary 1 Increased absolute kidney weight in female rats BMDL 10 (HED): 2.88 x 101
mg/kg-day
30 High

Reference Concentration for Inhalation Exposure (RfC) (PDF) (8 pp, 298 K) Last Updated: 08/13/2021

System RfC (mg/m3) Basis PoD Composite UF Confidence
Urinary 4 x 10 1 Increased absolute kidney weight in female rats NOAEL : 1.11 x 103
mg/m3
30 Medium

Cancer Assessment

Weight of Evidence for Cancer (PDF) (8 pp, 298 K) Last Updated: 08/13/2021

WOE Characterization Framework for WOE Characterization
Suggestive evidence of carcinogenic potential (Inhalation route) Guidelines for Carcinogen Risk Assessment (U.S. EPA, 2005)
Basis:
  • Under EPA’s Guidelines for Carcinogen Risk Assessment (U.S. EPA, 2005), ethyl tertiary butyl ether has “suggestive evidence of carcinogenic potential" for the inhalation route and “inadequate information to assess carcinogenic potential” for the oral route.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (8 pp, 298 K)

Information reviewed but value not estimated.


Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (8 pp, 298 K)

Inhalation Unit Risk: 8 x 10-5 per mg/m3
Extrapolation Method: Linear extrapolation from the POD ((BMCL10(HED)) associated with 10% extra cancer risk.
Tumor site(s): Hepatic
Tumor type(s): Hepatocellular adenomas and carcinomas (Saito et al. 2013; JPEC, 2010b)

Chemical Documents

Aug 2021: IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Final Report) (Report)

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

Jun 2017: IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft, 2017) (Report)

Sep 2016: IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Public Comment Draft, 2016) (Report)

Jun 2016: IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Interagency Science Consultation Draft, 2016) (Report)

Mar 2013: IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Preliminary Assessment Materials, 2013) (Report)

Aug 2009: IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (External Review Draft, 2009) (Report)

Other EPA Information

Additional EPA toxicity information may be available by visiting the following sites:
  • Human Health Benchmarks for Pesticides (HHBP). This database provides human health benchmarks for pesticides that may be present in drinking water.
  • Office of Pesticide Programs Pesticide Chemical Search. This database provides links to health effects information and registration status for pesticides.
  • Chemistry Dashboard. This database provides information on chemical structures, experimental and predicted physicochemical, and toxicity data.

Related Links

  • EPA Chemicals Dashboard - Ethyl Tertiary Butyl Ether (ETBE)
  • eChemPortal - Ethyl Tertiary Butyl Ether (ETBE)

Critical Effects

Urinary
Urinary

Tumor Sites

Hepatic
Hepatic

Chemical Structure

Ethyl Tertiary Butyl Ether (ETBE)

Synonyms

  • ETBE
  • ethyl 1,1-dimethylethyl ethyl ether
  • ethyl tert-butyl ether
  • ethyl tert-butyl oxide
  • ethylene glycol t-butyl ether
  • methyl-2-ethoxypropane
  • tert-butyl ethyl ether
  • 2-ethoxy-2-methylpropane
  • 2-methyl-2-ethoxypropane
  • 637-92-3
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