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Testing Status of Isoprene M200028


CASRN: 78-79-5

Formula: C5-H8

Synonyms/Common Names

  • 1,3-Butadiene, 2-methyl- (9CI)

Chemical Properties

Toxicity Effects (HSDB)

Short-Term Toxicity

  • 2 weeks (Inhalation)  (C61825)  Completed 
    • Rats: F344/N; Mice: B6C3F1
  • 26 weeks (Inhalation)  (C61825C)  Completed 
    • Rats: F344/N; Mice: B6C3F1
    • Dose: MALES ONLY; R&M: 0, 70, 220, 700, 2200, 7000 PPM.
  • 13 weeks (Inhalation)  (C61825)  Completed 
    • Rats: F344/N; Mice: B6C3F1
    • Dose: R&M: 0, 70, 220, 700, 2200, 7000 PPM.

Long-Term Carcinogenicity

  • 2 years (Inhalation)  (C61825B)  Completed 
    • TR-486 (NIH Number: 99-3976)  (Peer Review Approval 12/10/1997A )
      Toxicology and Carcinogenesis Studies of Isoprene (CASRN 78-79-5) in F344/N Rats (Inhalation Studies)
    • Rats: F344/N
    • Carcinogenesis Results
      • Male Rats Clear Evidence 
      • Female Rats Some Evidence 
    • Dose: R: 0, 220, 700, OR 7000 PPM; 50/SEX/GROUP.

Special Studies

  • Absorption Disposition Metabolism Elimination (Inhalation)  (S0227)  Completed 
    • Citation: Bond JA, Bechtold WE, Birnbaum LS, Dahl AR, Medinsky MA, Sun JD, Henderson RF. Disposition of inhaled isoprene in B6C3F1 mice. Toxicol Appl Pharmacol. 1991 Mar 1;107(3):494-503. Pubmed Abstract
    • Citation: Dahl AR, Birnbaum LS, Bond JA, Gervasi PG, Henderson RF. The fate of isoprene inhaled by rats: comparison to butadiene. Toxicol Appl Pharmacol. 1987 Jun 30;89(2):237-48.Pubmed Abstract
    • Male Rats: F344/N
  • Absorption Disposition Metabolism Elimination (Intraperitoneal Injection)  (S0460)  Completed 
    • Citation: Sun JD, Dahl AR, Bond JA, Birnbaum LS, Henderson RF. Characterization of hemoglobin adduct formation in mice and rats after administration of [14C]butadiene or [14C]isoprene. Toxicol Appl Pharmacol. 1989 Aug;100(1):86-95.Pubmed Abstract
    • Male Rats: Sprague Dawley; Male Mice: B6C3F1
    • Dose: 0.3, 3.0, 300, 1000 OR 3000 UMOL [14C]ISOPRENE.
  • Metabolism (Intraperitoneal Injection)  (S0338)  Completed 
    • Male Rats: F344/N; Male Mice: B6C3F1
    • Dose: PILOT 1: 33.2 MG/KG MOUSE; 66.6 MG/KG RAT; PILOT 2: 66.2 MG/KG RAT; STUDY A: 66.4 MG/KG RAT; STUDY CM: 68.4 MG/KG MOUSE..
  • Modeling  (S0648)  Completed 

    Genetic Toxicology

    • Chromosome Aberrations  (A63977)  Completed 
      • Mice
      •  Negative (Nonstandard Protocol) 
    • In Vitro Cytogenetics (CA/SCE)  (032841)  Completed 
      • Sister Chromatid Exchange Negative 
      • Chromosome Aberrations Negative 
    • Micronucleus  (A28566)  Completed 
      • Citation: Witt, K.L., Knapton, A., Wehr, C.M., Hook, G.J., Mirsalis, J., Shelby, M.D., and MacGregor, J.T. Micronucleated Erythrocyte Frequency in Peripheral Blood of B6C3F1 Mice from Short-Term, Prechronic, and Chronic Studies of the NTP Carcinogenesis Bioassay Program. Environ. Molec. Mutagen. Vol. 36 (2000) 163-194
      • Mice: B6C3F1
      • Male Positive 
      • Female Positive 
    • Micronucleus  (A63977)  Completed 
      • Mice: B6C3F1
      • Male Positive 
    • Salmonella  (453451)  Completed 
      • Citation: Mortelmans, K., Haworth, S., Lawlor, T., Speck, W., Tainer, B., and Zeiger, E. Salmonella mutagenicity tests. II. Results from the testing of 270 chemicals Environ. Mutagen. Vol. 8 (Suppl 7) (1986) 1-119
      •  Negative 
    • Sister Chromatid Exchanges  (A63977)  Completed 
      • Mice
      • Sister Chromatid  Positive (Nonstandard Protocol) 
    • Sister Chromatid Exchanges  (C78795)  Completed 
      • Citation: Tice, R.R., Boucher, R., Luke, C.A., Paquette, D.F., Melnick, R.L., and Shelby, M.D. Chloroprene and isoprene: Cytogenetic studies in mice. Mutagenesis. Vol. 3 (1988) 141-146
      • Mice
      • Sister Chromatid  Positive 

    Organ Systems Toxicity

    • 6 to 17 GD for mice Conventional Teratology (Inhalation)  (TER88045)  Completed 
      • Female Mice: Swiss
      • Mice Maternal Positive 
      • Mice Fetal Positive 
      • Dose: 0, 280, 1400, 7000 ppm.
    • 6 to 19 GD Conventional Teratology (Inhalation)  (TER88142)  Completed 
      • Rats: Sprague Dawley
      • Rats Maternal Negative 
      • Rats Fetal Negative 
      • Dose: 0, 280, 1400, 7000 ppm.