IRIS

1,2-Diphenylhydrazine

CASRN 122-66-7 | DTXSID7020710

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (11 pp, 107 K) Last Updated:
Not assessed under the IRIS Program.

 


Reference Concentration for Inhalation Exposure (RfC) (PDF) (11 pp, 107 K) Last Updated: 11/01/1991
Information reviewed but value not estimated.

 

Cancer Assessment

Weight of Evidence for Cancer (PDF) (11 pp, 107 K) Last Updated: 01/31/1987

WOE Characterization Framework for WOE Characterization
B2 (Probable human carcinogen - based on sufficient evidence of carcinogenicity in animals) Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986)
Basis:
  • Positive results of studies in both rats and mice form the basis for this classification. Two apparently negative studies lack information on compound purity, experimental design, and statistical treatment.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (11 pp, 107 K)

Oral Slope Factor: 8.0 x 10-1 per mg/kg-day
Drinking Water Unit Risk: 2.2 x 10-5 per µg/L
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Hepatic
Tumor type(s): Hepatocellular carcinomas and neoplastic liver nodules (NCI, 1979)


Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (11 pp, 107 K)

Inhalation Unit Risk: 2.2 x 10-4 per µg/m3
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Hepatic
Tumor type(s): Hepatocellular carcinomas and neoplastic liver nodules (NCI, 1979)


Additional EPA toxicity information may be available by visiting the following sites:

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