IRIS

Isophorone

CASRN 78-59-1

Health Hazard Assessments for Effects Other than Cancer

Reference Dose for Oral Exposure (RfD) (PDF) (15 pp, 125 K) last updated: 09/01/1989

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Urinary 2 x 10-1 Kidney pathology NOEL : 1.50 x 102
mg/kg-day
1000 Low

 


Reference Concentration for Inhalation Exposure (RfC) (PDF) (15 pp, 125 K) last updated: 03/01/1991
Information reviewed but value not estimated.

 

Cancer Assessment

Weight of Evidence for Cancer (PDF) (15 pp, 125 K) last updated: 10/01/1992

WOE Characterization Framework for WOE Characterization
C (Possible human carcinogen) Guidelines for Carcinogen Risk Assessment (US EPA, 1986)
Basis:
  • Based on no data in humans; limited evidence of carcinogenicity of one tumor type in one sex of one animal species as shown by an increase of preputial gland carcinomas in male rats. The apparent renal tubular cell tumor in the male rat is associated with alpha-2u-globulin, considered to be of questionable relevance to humans.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (15 pp, 125 K)

Oral Slope Factor: 9.5 x10 -4 per mg/kg-day
Drinking Water Unit Risk: 2.7 x10 -8 per µg/L
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Reproductive
Tumor type(s): Preputial gland carcinoma (NTP, 1986)



Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (15 pp, 125 K)

Not Assessed under the IRIS Program.

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