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Endrin

CASRN 72-20-8 | DTXSID6020561

  • IRIS Summary (PDF) (11 pp, 108 K)
  • Status: EPA announced in a 2004 Federal Register Notice that chemicals used as pesticides would not be re-assessed by the IRIS Program. This entry in the IRIS database is preserved at the request of EPA program and regional offices. Additional toxicological information may be found under "Other EPA Information."

On this page:

  • IRIS Toxicity
    Values
  • Other EPA
    Information

Noncancer Assessment

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

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 (U.S. 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.

Other EPA Information

Additional EPA toxicity information may be available by visiting the following sites:
  • Human Health Benchmarks for Pesticides (HHBP). This database provides human health benchmarks for pesticides that may be present in drinking water.
  • Office of Pesticide Programs Pesticide Chemical Search. This database provides links to health effects information and registration status for pesticides.
  • Chemistry Dashboard. This database provides information on chemical structures, experimental and predicted physicochemical, and toxicity data.

Related Links

  • EPA Chemicals Dashboard - Endrin
  • eChemPortal - Endrin

Critical Effects

Hepatic
Hepatic

Nervous
Nervous

Chemical Structure

Endrin

Synonyms

  • Endrin
  • Mendrin, 1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4(a)5,6,7,8,8a-octahydro-endo
  • 72-20-8
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