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Human Health Criteria
Chloroform
Notice of Availability of Draft Revised Human Health Criteria
Fact Sheet; January 2004
We announce the availability of a draft-Revised Human Health Ambient Water Quality Criteria (AWQC) for Chloroform, recommending draft criteria for Chloroform and requesting scientific views from the public. We have revised the criteria according to the procedures and information described in EPA's Methodology for Deriving Ambient Water Quality Criteria for the Protection of Human Health (2000 Human Health Methodology). The draft revised criteria reflect the Agency's consideration of recent advances in scientific information.
- Background
- What's new about the draft revised criteria?
- What are the Draft Revised National Recommended Water Quality Criteria for Chloroform?
- How do I get a copy of the new draft document?
Background
Chloroform (trichloromethane) is a colorless, volatile liquid. It is a nonflammable chemical that is slightly soluble in water. Because chloroform is relatively volatile, it tends to escape from contaminated water or soil into air. It may also be released in vapor from some types of industrial or chemical operations. Chloroform appears to be ubiquitous in the environment. It is derived primarily from various industrial and chemical processes, or as a by-product of disinfecting water with chlorine.
EPA originally published Human Health AWQC for chloroform in 1980 (45 FR 79318, October 1980). We updated these criteria by incorporating newer toxicity values from EPA's Integrated Risk Information System (IRIS) data base and published them in the 1992 Proposed National Toxics Rule (57 FR 60848). The criteria values promulgated in the National Toxics Rule are the same values in EPA's latest compilation of national recommended water quality criteria (67 FR 79091, December 27, 2002). The chloroform criteria currently recommended by EPA are: 5.7 ug/L for consumption of water + organisms and 470 ug/L for consumption of organisms only.
The EPA recommended AWQC provide guidance to states and authorized tribes in adopting water quality standards. The criteria provide a scientific basis for EPA to develop Federally promulgated water quality standards under section 303(c) of the Clean Water Act, should such action be necessary. Once final, these criteria are guidance for states and tribes and, in themselves, have no binding legal effect. However, they may form the basis for state water quality standards and become enforceable through NPDES permits or other environmental programs. These new draft revised chloroform criteria are published pursuant to Section 304(a) of the Clean Water Act (CWA).
What's new about the draft revised criteria?
The draft revised criteria reflect the Agency's consideration of the recent advances in scientific information available since the 2002 criteria were recommended. We have revised the criteria by implementing the 2000 Human Health Methodology. Specifically, we have incorporated:
- the national fish consumption rate (17.5 grams per day) recommended in the 2000 Human Health Methodology;
- the IRIS reference dose (RfD) that was revised in October 2001;
- new relative source contribution (RSC) analysis and values derived using data from the Relative Source Contribution document recently developed by the Office of Water in support of the Stage 2 Disinfectants and Disinfection Byproducts - Proposed Rule (68 FR49548); and
- bioaccumulation factors developed according to the procedures described in the 2000 Human Health Methodology.
What are the Draft Revised National Recommended Water Quality Criteria for Chloroform?
The draft revised criterion is 68 ug/L for consumption of water and aquatic organisms and 2,400 ug/L for consumption of aquatic organisms only.
How do I get a copy of the new draft chloroform document?
You can download a copy of the Water Quality Criteria for the Protection of Human Health: Chloroform—Revised Draft (PDF) (81 pp., 594 K; EPA-822-R-04-002).