TERTIARY-AMYL METHYL ETHER (TAME)
Update: April 2006
Current Massachusetts Regulatory Limit
ORSGL = 0.09 mg/L.
Federal Regulatory Limit
No MCL available
Basis for Criteria
The ORS guideline for TAME was derived based on the RfD (presented below) derived by ORS for this chemical and assumes that a 70 kg adult ingests 2 L/day of drinking water. A relative source contribution factor of 20% and a relative source contribution factor to account for potential carcinogenicity are incorporated into the final value.
RfD: 0.125 mg/kg/day (MassDEP, 2006)
UF: 1000 (10 = subchronic to chronic; 10 = interspecies; 10 = intraspecies)
Exposure to high concentrations of TAME has produced effects on the central nervous system, liver and kidney. In a 28-day subchronic oral study, 10 Sprague-Dawley rats per group were administered 125, 500 or 1000 mg/kg/day of TAME via gavage 7 days per week for 28 days. Dose-related, statistically significant increases in adrenal and kidney weights were seen at the 500 and 1000 mg/kg/day doses in male rats. ORS identified a NOAEL of 125 mg/kg/day from this study (MassDEP, 2006).
Cancer Assessment: The U.S. EPA has not classified TAME under either the old U.S. EPA carcinogen classification system or under their Proposed Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1999a). Using the 1999 proposed guidelines, ORS would tentatively classify TAME as having suggestive evidence of carcinogenicity but not sufficient to assess human carcinogenic potential.
PQL: 5 ug/L
U.S. EPA Method 8260 and 524.2
PQLs and analytical methods may have been updated since this guidance value was last revised. Updated analytical methods for drinking water and their associated PQLs may be found at http://www.epa.gov/safewater/methods/methods.html.
Other Regulatory Data
Any Health Advisories, Reference Doses (RfDs), cancer assessments or Cancer Potency Factors (CPFs) referenced in this document pertain to the derivation of the current guidance value. Updated information may be obtained from the following sources:
Health Advisories - The U.S. EPA provides guidance for shorter-term exposures for chemicals based on their non-cancer effects. Current health advisories may be more current than those used to derive MCLs and may be found at http://www.epa.gov/safewater/methods/methods.html.
RfDs, cancer assessments and CPFs - For specific information pertaining to derivation of drinking water criteria, consult the Federal Register notice that announces the availability of the most current guidance for that chemical. In addition, information on other current RfDs and CPFs as well as cancer assessments for specific chemicals may be found in the U.S. EPA Integrated Risk Information System (IRIS) at http://www.epa.gov/iris/. Please note that the information in IRIS may differ from that used in the derivation process as published in the Federal Register notice.
Massachusetts Department of Environmental Protection (MassDEP). March 27, 2006. Drinking Water Guideline for Tertiary-Amyl Methyl Ether (TAME). Office of Research and Standards (ORS).
U.S. EPA (U.S. Environmental Protection Agency). July 1999a. Guidelines for Carcinogen Risk Assessment. Review Draft. NCEA-F-0644. Risk Assessment Forum.