IRIS

Endrin

CASRN 72-20-8

Health Hazard Assessments for Effects Other than Cancer

Reference Dose for Oral Exposure (RfD) (PDF) (11 pp, 108 K) last updated: 09/07/1988

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Nervous, Hepatic 3 x 10-4 Mild histological lesions in liver, occasional convulsions NOEL : 2.5 x 10-2
mg/kg-day
100 Medium
Nervous, Hepatic 3 x 10-4 Mild histological lesions in liver, occasional convulsions NOEL : 2.5 x 10-2
mg/kg-day
100 Medium

 


Reference Concentration for Inhalation Exposure (RfC) (PDF) (11 pp, 108 K)
Not assessed under the IRIS Program.

 

Cancer Assessment

Weight of Evidence for Cancer (PDF) (11 pp, 108 K) last updated: 10/01/1989

WOE Characterization Framework for WOE Characterization
D (Not classifiable as to human carcinogenicity) Guidelines for Carcinogen Risk Assessment (US EPA, 1986)
Basis:
  • Oral administration of endrin did not produce carcinogenic effects in either sex of two strains of rats and three strains of mice. An NCI bioassay was suggestive of responses in male and female rats although NCI reported a no evidence conclusion. The inadequacies of several of the bioassays call into question the strength of the reported negative findings. These inadequacies and the suggestive responses in the NCI bioassay do not support a Group E classification; rather a Group D classification best reflects the equivocal data.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (11 pp, 108 K)

Not assessed under the IRIS Program.

Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (11 pp, 108 K)

Not assessed under the IRIS Program.

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