Methyl Tertiary Butyl Ether
CAS Number
1634-04-4Synonym
Methyl tert-butyl ether; Methyl t-butyl ether; Tert-butyl methyl ether; T-butyl methyl ether; MTBE; 2-methoxy-2-methylpropane; Methyl-tert-butyl ether; methyl 1,1-dimethylethyl ether; 2-methyl-2-methoxypropane
Occurrence/Use
Gasoline additive (oxygenate; improves octane ratings and reduces pollutant emission); medicine (dissolves cholesterol gall stones)
Soil Screening
| Last CHHSL revision: | 1/2005 |
|---|---|
| CHHSL Comments: |
For chemical-specific screening levels for use in assessing contaminated sites, please see HHRA Note 3 (DTSC HERO). https://www.dtsc.ca.gov/assessingrisk/humanrisk2.cfm |
Cancer Potency Information
| Inhalation Unit Risk (μg/cubic meter)-1: | 2.6 E-7 |
|---|---|
| Inhalation Slope Factor (mg/kg-day)-1: | 1.8 E-3 |
| Oral Slope Factor (mg/kg-day)-1: | 1.8 E-3 |
| Comments/References: |
OEHHA 2009. Air Toxics Hot Spots Program Technical Support Document for Cancer Potencies. Appendix B. Chemical-specific summaries of the information used to derive unit risk and cancer potency values. Updated 2011. Listed as Methyl Tert-Butyl Ether (MTBE).
OEHHA 1999. Public Health Goal for Methyl Tertiary Butyl Ether (MTBE) in Drinking Water. |
Air
Chronic REL
| Chronic Inhalation REL (μg/m3): | 8000 |
|---|---|
| Chronic Target Organs: | Kidney; eyes; alimentary system (liver) |
| Human Data: | No |
| Last Chronic REL Revision: | 2000 |
| Chronic Reference Exposure Levels Comments: |
OEHHA 2008. Technical Supporting Document for Noncancer RELs, Appendix D3
|
Proposition 65
Chemical Status
| Cancer: | Considered, but not listed |
|---|---|
| Reproductive Toxicity : | Considered, but not listed |
Documents, Presentations, and Publications
| Cancer: |
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| Reproductive Toxicity: |
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Public notices related to this chemical
- Chemicals Proposed for Listing by the Labor Code Mechanism (Reproductive and Developmental Toxicants)
- December 10, 1998 Meeting of the CIC
- December 9, 1998 Meeting of the DART IC
- Availability of the Draft Hazard Identification Documents for Methyl Tertiary-Butyl Ether (MTBE)
- Request for Information on Methyl Tertiary-Butyl Ether (MTBE)
Water
California Public Health Goals Data
| Health Risk Category: | Carcinogenicity |
|---|---|
| Public Health Goal (mg/L): | 0.013 |
| Public Health Goal - Download: | mtbef.pdf |
| Cancer Risk at PHG: | 0.000001 |
| MCL value (mg/L): | 0.013 |
| Cancer Risk at MCL: | 0.000001 |
| Last PHG Revision : | 1999 |
| California PHG Comments: | OEHHA 2013. Health Risk Information for Public Health Goal Exceedance Reports |