You are here:
- IRIS Summary (PDF) (11 pp, 112 K)
- Status: 3,3'-Dichlorobenzidine is not being reassessed by IRIS at this time.
Health Hazard Assessments for Effects Other than Cancer
Reference Dose for Oral Exposure (RfD) (PDF) (11 pp, 112 K)
Not assessed under the IRIS Program.
Reference Concentration for Inhalation Exposure (RfC) (PDF) (11 pp, 112 K)
last updated: 11/01/1991
Information reviewed but value not estimated.
Weight of Evidence for Cancer (PDF) (11 pp, 112 K)
last updated: 07/01/1993
|WOE Characterization||Framework for WOE Characterization|
|B2 (Probable human carcinogen - based on sufficient evidence of carcinogenicity in animals)||Guidelines for Carcinogen Risk Assessment (US EPA, 1986)|
- Based on statistically significantly increased tumor incidences in rats, mice and dogs. Additional support is provided by positive evidence of genotoxicity and structural relationship to the known human bladder carcinogen benzidine.
- This may be a synopsis of the full weight-of-evidence narrative.
Oral Slope Factor:
4.5 x10 -1 per mg/kg-day
Drinking Water Unit Risk: 1.3 x10 -5 per µg/L
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Reproductive
Tumor type(s): Mammary adenocarcinoma (Stula et al., 1975)
Not Assessed under the IRIS Program.
You will need Adobe Reader to view some of the files on this page. See EPA’s PDF page to learn more.