- IRIS Summary (PDF) (13 pp, 116 K)
Reference Dose for Oral Exposure (RfD) (PDF) (13 pp, 116 K)
last updated: 09/30/1987
|System||RfD (mg/kg-day)||Basis||PoD||Composite UF||Confidence|
|Hepatic||2 x 10-2||Hepatic lesions||
: 2.14 x 101
Reference Concentration for Inhalation Exposure (RfC) (PDF) (13 pp, 116 K)
Not assessed under the IRIS Program.
Weight of Evidence for Cancer (PDF) (13 pp, 116 K)
last updated: 01/01/1992
|WOE Characterization||Framework for WOE Characterization|
|C (Possible human carcinogen)||Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986)|
- Based on inadequate human data and limited evidence of carcinogenicity in animals; namely, positive carcinogenic evidence in B6C3Fl mice (males and females), together with positive mutagenicity data, and structural similarity to other trihalomethanes, which are known animal carcinogens.
- This may be a synopsis of the full weight-of-evidence narrative.
Oral Slope Factor:
8.4 x 10 -2 per mg/kg-day
Drinking Water Unit Risk: 2.4 x 10 -6 per µg/L
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Hepatic
Tumor type(s): Hepatocellular adenoma or carcinoma (NTP, 1985)
Not Assessed under the IRIS Program.
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