Methyl tert-butyl ether (MTBE)

CASRN 1634-04-4

  • IRIS Summary (PDF) (25 pp, 170 K)
  • Status: Methyl tert-butyl ether (MTBE) is not being reassessed by IRIS at this time.

Health Hazard Assessments for Effects Other than Cancer


Reference Dose for Oral Exposure (RfD) (PDF) (25 pp, 170 K)
Not assessed under the IRIS Program.

Reference Concentration for Inhalation Exposure (RfC) (PDF) (25 pp, 170 K) last updated: 09/01/1993

RfC (mg/m3) System Basis PoD Composite UF Confidence
3 Hepatic, Urinary, Ocular, Other Increased absolute and relative liver and kidney weights and increased severity of spontaneous renal lesions (females), increased prostration (females), and swollen periocular tissue (males and females) NOAEL (HEC): 2.59 x102
mg/m3
100 Medium

Cancer Assessment


Weight of Evidence for Cancer (PDF) (25 pp, 170 K)
Not assessed under the IRIS Program.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (25 pp, 170 K)

Not assessed under the IRIS Program.

Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (25 pp, 170 K)

Not assessed under the IRIS Program.

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