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Chemical Sampling Information (CSI)
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General Description

Synonyms: Dioxin; Dioxine; TCDBD; TCDD; 2,3,7,8-TCDD

OSHA IMIS Code Number: 2326

Chemical Abstracts Service (CAS) Registry Number: 1746-01-6

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: HP3500000

NIOSH Pocket Guide to Chemical Hazards, 2,3,7,8-Tetrachloro-dibenzo-p-Dioxin: chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): Appendix A - NIOSH Potential Occupational Carcinogens

Health Factors

Carcinogenic Classification:
International Agency for Research on Cancer (IARC): Group 1, carcinogenic to humans [21 MB PDF, 311 pages]

National Toxicology Program (NTP): Group 1, known to be human carcinogen [189 KB PDF, 3 pages]
Potential Symptoms: Eye irritation; allergic dermatitis, chloracne; porphyria; headache; weakness; gastrointestinal disturbance; possible reproductive, teratogenic effects. In animals: liver, kidney damage; hemorrhage; endometriosis; developmental neurotoxicity; immunosuppression; endocrine disturbances, reproductive problems; [potential occupational carcinogen].

Health Effects: Known human carcinogen (HE2); Chronic toxicity---Chloracne, hyperlipidemia (HE3); Irritation-Eyes, nose, throat, skin---Moderate (HE15)

Affected Organs: Eyes, skin, liver, kidneys, reproductive system

  1. The body burden LOAEL for chloracne has been estimated to be 160 ng/kg. A 2001 follow-up study of 12 workers who acquired TCDD-induced chloracne in the late 1960s indicated that two still had it.
  2. Up to 30 years or more following occupational exposure, high incidences of hyperlipidemia (cholesterol, triglycerides), ischaemic heart disease (atherosclerosis, thicker carotid wall and plaques, hypertension), and neuropsychological complaints (e.g., memory) have been reported.
  3. TCDD binds to the aryl hydrocarbon receptor (AhR) and, due to a very slow elimination in humans (half-life >7 years), this can lead to chronic activation of AhR-driven gene expression, including induction of several drug-metabolizing enzymes (e.g., CYP1A1, CYP1A2, CYP1B1, glutathione S-transferase, UDP-glucuronosyltransferase), which may bind TCDD (e.g., CYP 1A2) but do not metabolize it.
Date Last Revised: 08/13/2004

Literature Basis:
  • NIOSH Pocket Guide to Chemical Hazards: 2,3,7,8-Tetrachlorodibenzo-p-Dioxin.
  • International Chemical Safety Cards (WHO/IPCS/ILO): 2,3,7,8-Tetrachlorodibenzo-p-dioxin.
  • Cole, P., Trichopoulos, D., Pastides, H., Starr, T. and Mandel, J.S.: Dioxin and cancer: a critical review. Regul. Toxicol. Pharmacol. 38(3): 378-388, 2003.
  • Greene, J.F., Hays, S. and Paustenbach, D.: Basis for a proposed reference dose (RfD) for dioxin of 1-10 pg/kg-day: a weight of evidence evaluation of the human and animal studies. J. Toxicol. Environ. Health B Crit. Rev. 6(2): 115-159, 2003.
  • Inouye, K., Shinkyo, R., Takita, T., Ohta, M. and Sakaki, T.: Metabolism of polychlorinated dibenzo-p-dioxins (PCDDs) by human cytochrome P450-dependent monooxygenase systems. J. Agric. Food Chem. 50(19): 5496-5502, 2002.
  • Kakeyama, M. and Tohyama, C.: Developmental neurotoxicity of dioxin and its related compounds. Ind. Health 41(3): 215-230, 2003.
  • Miller, K.P., Borgeest, C., Greenfeld, C., Tomic, D. and Flaws, J.A.: In utero effects of chemicals on reproductive tissues in females. Toxicol. Appl. Pharmacol. 198(2): 111-131, 2004.
  • Pelclová, D., et al.: Lipid metabolism and neuropsychological follow-up study of workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Int. Arch. Occup. Environ. Health 75(Suppl.): S60-S66, 2002.
  • Pohanish, R.P. (editor): Tetrachlorodibenzo-p-dioxin. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 2158-2160.
  • Takemoto, K., Nakajima, M., Fujiki, Y., Katoh, Miki, Gonzalez, F.J. and Yokoi, T.: Role of the aryl hydrocarbon receptor and Cyp 1b1 in the antiestrogenic activity of 2,3,7,8-tetrachlorodibenzo-p-dioxin. Arch. Toxicol. 78(6): 309-315, 2004.
  • Uno, S., et al.: Cyp1a1(-/-) male mice: protection against high-dose TCDD-induced lethality and wasting syndrome, and resistance to intrahypatocyte lipid accumulation and uroporphyria. Toxicol. Appl. Pharmacol. 196(3): 410-421, 2004.
Monitoring Methods used by OSHA

Laboratory Sampling/Analytical Method:
  • note: Call SLTC for sampling procedure.
Bulk Method: Limit the amount of bulk submitted to one gram or one mL.

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Page last updated: 06/14/2005

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