1,2-Diphenylhydrazine

CASRN 122-66-7

  • IRIS Summary (PDF) (11 pp, 107 K)
  • Status: 1,2-Diphenylhydrazine 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, 107 K)
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 (US 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 x10 -1 per mg/kg-day
Drinking Water Unit Risk: 2.2 x10 -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 x10 -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)


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