National Toxicology Program

National Toxicology Program

Testing Status of Heptachlor - 10875-C


CASRN: 76-44-8

Formula: C10-H5-Cl7

Synonyms/Common Names

  • 1,4,5,6,7,8,8-Heptachloro-3a,4,7,7a-tetrahydro-4,7-methano-1H-indene (9CI)

Known Uses

Subterranean termite control. Dipping of roots or tops of non-food plants for insect control (NTP executive summary). Associated with tobacco: reported either as a natural component of tobacco, pyrolysis product (in tobacco smoke), or additive for one or more types of tobacco products.

Chemical Properties

Toxicity Effects (HSDB)

Nomination Background

Short-Term Toxicity

  • 14-Day (Dosed-Feed)  (C00180)  Completed 
    • Rats: Osborne Mendel; Mice: B6C3F1
  • 13-Week (Dosed-Feed)  (C00180)  Completed 
    • Rats: Osborne Mendel; Mice: B6C3F1
    • Dose: 0,20,320 PPM/5 PER GROUP.

Long-Term Carcinogenicity

  • 2-Year (Dosed-Feed)  (C00180)  Report Complete 
    • TR-009 (NIH Number: 77-809)  (Peer Review Approval NA)
      Bioassay of Heptachlor for Possible Carcinogenicity (CASRN 76-44-8)
    • Rats: Osborne Mendel; Mice: B6C3F1
    • Carcinogenesis Results
      • Male Rats Negative 
      • Female Rats Equivocal 
      • Male Mice Positive 
      • Female Mice Positive 
    • Dose: MR: 0,38.9,77.9 (AVG), FR: 0,25.7,51.3 (AVG), MM: 0,6.1,13.8 (AVG), FM: 0,9,18 (AVG) PPM/50 PER GROUP.

Special Studies

  • Absorption Disposition Metabolism Elimination (Intravenous)  (S0197)  Completed 
    • Citation: The Toxicologist 1, P. 136, Abstract No. 494, 1981 (Tuey, DB and Matthews HB) The Pharmacokinetics of Heptachlor Disposition in the Rat.
    • Male Rats: F344/N

Genetic Toxicology

  • In Vitro Cytogenetics (CA/SCE)  (234168)  Completed 
    • Sister Chromatid Exchange Weakly Positive 
    • Chromosome Aberrations Negative 
  • In Vitro Cytogenetics (CA/SCE)  (616642)  Completed 
    • Sister Chromatid Exchange Not a Valid Test 
    • Chromosome Aberrations Positive 
  • Mouse Lymphoma  (466460)  Completed 
    • Citation: McGregor, D., Brown, A., Cattanach, P., Edwards, I., McBride, D., Riach, C., and Caspary, W. Responses of the L5178Y tk+/tk- mouse lymphoma cell forward mutation assay: III. 72 coded chemicals. Environ. Molec. Mutagen. Vol. 12 (1988) 85-154
    • Mice
    •  Positive 
  • Salmonella  (339937)  Completed 
    • Citation: Zeiger E, Anderson B, Haworth S, Lawlor T, Mortelmans K, Speck W. Salmonella mutagenicity tests: III. Results from the testing of 255 chemicals. Environ Mutagen. 1987;9 Suppl 9:1-109.
    •  Negative 
  • Salmonella  (939541)  Completed 
    •  Negative 

Organ Systems Toxicity

  • varies Immunotoxicity (Topical Application)  (IMM20709)  Completed 
    • Female Mice: BALB/c
    • Dose: 0, 0.5, 1, 2.5, 5, 10, 25, or 50%.
  • Juvenile Pesticide Assessment (Gavage)  (JPA20701)  Completed 
    • Male and Female Rats: Sprague Dawley
    • Dose: 0, 30, 300, OR 3000 UG/KG/DAY FROM GESTATION DAY (GD) 12 THROUGH PND 7.
  • 49 days Juvenile Pesticide Assessment (Gavage)  (JPA98001)  Completed 
    • Male and Female Rats: Sprague Dawley
    • Dose: 0, 30, 100, OR 3000 UG/KG/DAY.
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.