IRIS

Hexachlorobenzene

CASRN 118-74-1

Health Hazard Assessments for Effects Other than Cancer

Reference Dose for Oral Exposure (RfD) (PDF) (16 pp, 129 K) last updated: 09/26/1988

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Hepatic 8 x 10-4 Liver effects NOAEL : 8 x 10-2
mg/kg-day
100 Medium

 


Reference Concentration for Inhalation Exposure (RfC) (PDF) (16 pp, 129 K) last updated: 03/01/1991
Information reviewed but value not estimated.

 

Cancer Assessment

Weight of Evidence for Cancer (PDF) (16 pp, 129 K) last updated: 03/01/1991

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:
  • Hexachlorobenzene, when administered orally, has been shown to induce tumors in the liver, thyroid and kidney in three rodent species.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (16 pp, 129 K)

Oral Slope Factor: 1.6 per mg/kg-day
Drinking Water Unit Risk: 4.6 x10 -5 per µg/L
Extrapolation Method: Linearized multistage, extra risk
Tumor site(s): Hepatic
Tumor type(s): Hepatocellular carcinoma (Erturk et al., 1986)



Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (16 pp, 129 K)

Inhalation Unit Risk: 4.6 x10 -4 per µg/m3
Extrapolation Method: Linearized multistage, extra risk
Tumor site(s): Hepatic
Tumor type(s): Hepatocellular carcinoma (Erturk et al., 1986)


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