Update: March 1996
Current Massachusetts Regulatory Limit
MMCL = 0.005 mg/L. ORS has adopted the MCL published by the U.S. EPA (52 FR 25690 (7/8/87) and 56 FR 3526 (1/30/91)).
Federal Regulatory Limit
The MCL of 0.005 mg/L for trichloroethylene (TCE) is equal to its PQL of 0.005 mg/L. The MCLG is equal to zero.
Basis for Criteria
The MCLG is set at zero based on the evidence for carcinogenic potential of a B2 carcinogen. The MCL is set at the trichloroethylene PQL.
The critical health effect from exposure to trichloroethylene is a potential increase in the incidence of cancer. In addition, long-term exposure to trichloroethylene may damage the liver and kidneys and may produce effects on the CNS and depression in myocardial contractility.
Cancer Assessment: B2
A carcinogen assessment summary for trichloroethylene has been withdrawn. A new carcinogen summary is in preparation by the CRAVE workgroup. Significant increases in the incidence of liver tumors have been reported in mice. Malignant lymphoma and adenocarcinoma were also reported in mice.
PQL: 0.005 mg/L
U.S. EPA 502.1; gas chromatography
U.S. EPA 503.1; gas chromatography
U.S. EPA 524.2; gas chromatography-mass spectrometry
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/waterscience/drinking/standards/dwstandards.pdf.
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.
Federal Register. June 12, 1984. Part V. Environmental Protection Agency. 40 CFR Part 141. National Primary Drinking Water Regulations; Volatile Synthetic Organic Chemicals; Proposed Rulemaking. (49 FR 24329).
Federal Register. July 8, 1987. Environmental Protection Agency. 40 CFR Parts 141 and 142. National Primary Drinking Water Regulations; Synthetic Organic Chemicals; Monitoring for Unregulated Contaminants; Final Rule. (52 FR 25689).
Federal Register. January 30, 1991. Part II. Environmental Protection Agency. 40 CFR Parts 141, 142, and 143. National Primary Drinking Water Regulations; Final Rule. (56 FR 3526).