- IRIS Summary (PDF) (14 pp, 118 K)
Reference Dose for Oral Exposure (RfD) (PDF) (14 pp, 118 K)
last updated: 09/26/1988
|System||RfD (mg/kg-day)||Basis||PoD||Composite UF||Confidence|
|Hepatic||5 x 10-4||Liver effects||
: 5 x 10-1
Reference Concentration for Inhalation Exposure (RfC) (PDF) (14 pp, 118 K)
Not assessed under the IRIS Program.
Weight of Evidence for Cancer (PDF) (14 pp, 118 K)
last updated: 06/01/1989
|WOE Characterization||Framework for WOE Characterization|
|C (Possible human carcinogen)||Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986)|
- Evidence of human carcinogenicity is inadequate. Urinary bladder papilloma and carcinoma were observed in female Fischer 344 rats. Mutagenic activity was observed in Salmonella with and without metabolic activation.
- This may be a synopsis of the full weight-of-evidence narrative.
Oral Slope Factor:
3.0 x 10 -2 per mg/kg-day
Drinking Water Unit Risk: 9.0 x 10 -7 per µg/L
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Urinary
Tumor type(s): Urinary bladder, transitional cell papilloma and transitional squamous cell carcinomas (U.S. DOD, 1984a)
Not Assessed under the IRIS Program.
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