IRIS

Vinyl chloride

CASRN 75-01-4 | DTXSID8021434

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (64 pp, 341 K) Last Updated: 08/07/2000

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Hepatic 3 x 10 -3 Liver cell polymorphism NOAEL (HED): 9 x 10-2
mg/kg-day
30 Medium

 


Reference Concentration for Inhalation Exposure (RfC) (PDF) (64 pp, 341 K) Last Updated: 08/07/2000

System RfC (mg/m3) Basis PoD Composite UF Confidence
Hepatic 1 x 10 -1 Liver cell polymorphism NOAEL (HEC): 2.5
mg/m3
30 Medium

 

Cancer Assessment

Weight of Evidence for Cancer (PDF) (64 pp, 341 K) Last Updated: 08/07/2000

WOE Characterization Framework for WOE Characterization
A (Human carcinogen) Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986)
Known/likely human carcinogen Proposed Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1996)
Basis:
  • On the basis of sufficient evidence for carcinogenicity in human epidemiology studies, VC is considered to best fit the weight-of-evidence Category "A," according to current EPA Risk Assessment Guidelines (U.S. EPA, 1986). Under the Proposed Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1996), it is concluded that VC is a known human carcinogen by the inhalation route of exposure, based on human epidemiological data, and by analogy the oral route because of positive animal bioassay data as well as pharmacokinetic data allowing dose extrapolation across routes. VC is also considered highly likely to be carcinogenic by the dermal route because it is well absorbed and acts systemically.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (64 pp, 341 K)

Oral Slope Factor: 7.2 x 10-1 per mg/kg-day (Continuous lifetime exposure during adulthood)
Drinking Water Unit Risk: 2.1 x 10-5 per µg/L x 10 (Continuous lifetime exposure during adulthood)
Extrapolation Method: LMS method
Tumor site(s): Hepatic
Tumor type(s): Total of liver angiosarcoma, hepatocellular carcinoma, and neoplastic nodules (Feron et al., 1981)

Oral Slope Factor: 7.5 x 10-1 per mg/kg-day (Continuous lifetime exposure during adulthood)
Drinking Water Unit Risk: 2.1 x 10-5 per µg/L x 10 (Continuous lifetime exposure during adulthood)
Extrapolation Method: LED 10/ linear method
Tumor site(s): Hepatic
Tumor type(s): Total of liver angiosarcoma, hepatocellular carcinoma, and neoplastic nodules (Feron et al., 1981)

Oral Slope Factor: 1.4 per mg/kg-day (Continuous lifetime exposure from birth)
Drinking Water Unit Risk: 4.2 x 10-5 per µg/L x 10 (Continuous lifetime exposure from birth)
Extrapolation Method: LMS method
Tumor site(s): Hepatic
Tumor type(s): Total of liver angiosarcoma, hepatocellular carcinoma, and neoplastic nodules (Feron et al., 1981)

Oral Slope Factor: 1.5 per mg/kg-day (Continuous lifetime exposure from birth)
Drinking Water Unit Risk: 4.2 x 10-5 per µg/L x 10 (Continuous lifetime exposure from birth)
Extrapolation Method: LED 10/ linear method
Tumor site(s): Hepatic
Tumor type(s): Total of liver angiosarcoma, hepatocellular carcinoma, and neoplastic nodules (Feron et al., 1981)


Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (64 pp, 341 K)

Inhalation Unit Risk: 4.4 x 10-6 per µg/m3 (Continuous lifetime exposure during adulthood)
Extrapolation Method: LMS method
Tumor site(s): Hepatic
Tumor type(s): Liver angiosarcomas, angiomas, hepatomas, and neoplastic nodules (Maltoni et al. (1981, 1984))

Inhalation Unit Risk: 8.8 x 10-6 per µg/m3 (Continuous lifetime exposure from birth)
Extrapolation Method: LMS method
Tumor site(s): Hepatic
Tumor type(s): Liver angiosarcomas, angiomas, hepatomas, and neoplastic nodules (Maltoni et al. (1981, 1984))

Inhalation Unit Risk: 4.4 x 10-6 per µg/m3 (Continuous lifetime exposure during adulthood)
Extrapolation Method: LED 10/ linear method
Tumor site(s): Hepatic
Tumor type(s): Liver angiosarcomas, angiomas, hepatomas, and neoplastic nodules (Maltoni et al. (1981, 1984))

Inhalation Unit Risk: 8.8 x 10-6 per µg/m3 (Continuous lifetime exposure from birth)
Extrapolation Method: LED 10/ linear method
Tumor site(s): Hepatic
Tumor type(s): Liver angiosarcomas, angiomas, hepatomas, and neoplastic nodules (Maltoni et al. (1981, 1984))

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