National Toxicology Program

CASRN: 76-44-8

Formula: C10-H5-CL7

Synonyms/Common Names:

• 1,4,5,6,7,8-HEPTOCHLORO-3A,4,7,7A-TETRAHYDRO-4,7-METHANO-INDENE (9CI)

Known Uses:

SUBTERRANEAN TERMITE CONTROL. DIPPING OF ROOTS OR TOPS OF NON-FOOD PLANTS FOR INSECT CONTROL (NTP EXECUTIVE SUMMARY)

Nomination Background

Short-Term Toxicity

• 14-Day (Dosed-Feed)  (C00180) Completed 
  • NTIS No. PB271967  (Peer Review NA)
    Citation: Bioassay of Heptachlor for Possible Carcinogenicity (CAS No. 76-44-8)
  • Rats: Osborne Mendel; Mice: B6C3F1
• 13-Week (Dosed-Feed)  (C00180) Completed 
  • NTIS No. PB271967  (Peer Review NA)
    Citation: Bioassay of Heptachlor for Possible Carcinogenicity (CAS No. 76-44-8)
  • 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 (NTIS No. PB271967)  (Peer Review NA)
    Bioassay of Heptachlor for Possible Carcinogenicity (CAS No. 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.
  • M Rats: F344/N; M Rats: F344/N

Genetic Toxicology

• In Vitro Cytogenetics (CA/SCE)  (234168) Completed 
  • Chromosome Aberation Negative 
  • Sister Chromatid Exchange Weakly Positive 
• In Vitro Cytogenetics (CA/SCE)  (616642) Completed 
  • Chromosome Aberation Positive 
  • Sister Chromatid Exchange Not Tested 
• 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
  •  Positive 
• Salmonella  (339937) Completed 
  • Citation: Zeiger, E., Anderson, B., Haworth, S., Lawlor, T., Mortelmans, K., and Speck, W. Salmonella mutagenicity tests. III. Results from the testing of 225 chemicals Environ. Mutagen. Vol. 9 (Suppl 9) (1987) 1-109
  •  Negative 
• Salmonella  (939541) Completed 
  •  Negative 

Organ Systems Toxicity

• Varies Immunotoxicity (Topical Application)  (IMM20709) Report in Preparation 
  • F Mice: BALB/c
  • Dose: 0, 0.5, 1, 2.5, 5, 10, 25, OR 50%
• Juvenile Pesticide Assessment (Gavage)  (JPA20701) Completed 
  • M/F 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 
  • M/F Rats: Sprague Dawley
  • Dose: 0, 30, 100, OR 3000 UG/KG/DAY