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General Description

  • Synonyms: 1,3-Dichlorobenzene; m-Dichlorobenzol; m-Phenylene dichloride
  • OSHA IMIS Code Number: D149
  • Chemical Abstracts Service (CAS) Registry Number: 541-73-1
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: CZ4499000
  • Chemical Description and Physical Properties:
    • colorless liquid
    • molecular weight: 147.0
    • vapor pressure: 0.286 kPa @ 25°C
    • molecular formula: C6H4Cl2
    • boiling point: 173°C
    • melting point: -24.8°C
    • flash point: 63°C closed cup
  • Incompatibilities: reacts violently with aluminium

Health Factors

  • Carcinogenic Classification:
  • Potential Symptoms: Irritation of eyes, nose, throat, skin; cough, sore throat; drowsiness, nausea, vomiting; skin blisters; in animals: liver, kidney damage; Ingestion Acute; Burning sensation; nausea, vomiting, diarrhea.
  • Health Effects: Irritation-Eye, Nose, Throat, Skin---Moderate (HE15); Liver damage (HE4)
  • Affected Organs: Eyes, skin, respiratory system, liver
  • Notes:
    1. OSHA does not have a PEL for m-dichlorobenzene.
    2. Explosive vapor/air mixtures of m-dichlorobenzene may be formed at temperatures above 63°C.
    3. Urinary metabolites of m-dichlorobenzene in rats include 2,4- and 3,5-dichlorophenyl methyl sulfoxides and methyl sulfones, as well as mercapturic acid derivatives.
    4. The hepatotoxicity of m-dichlorobenzene may be due to production of reactive metabolites that bind covalently to liver proteins, as well as to oxidative stress from the intracellular depletion of reduced glutathione (GSH). Hepatotoxicity in rats is markedly increased by pretreatment with phenobarbital to induce metabolizing enzymes.
  • Literature Basis:
    • International Chemical Safety Cards (WHO/IPCS/ILO): 1,3-Dichlorobenzene.
    • U.S. EPA Integrated Risk Information System: 1,3-Dichlorobenzene (CASRN 541-73-1).
    • Kimura, R., Sano, H., Itagaki, K., Kogure, T., Sato, M. and Murata, T.: Identification of sulfer-containing metabolites of m-dichlorobenzene and their disposition and relationship with glutathione in rats. J. Pharmacobiodyn. 7(4): 234-245, 1984.
    • McCauley, P.T., Robinson, M., Daniel, F.B. and Olson, G.R.: Toxicity studies of 1,3-dichlorobenzene in Sprague-Dawley rats. Drug Chem. Toxicol. 18(2-3): 201-221, 1995.
    • No authors listed: Dichlorobenzenes. IARC Monogr. Eval. Carcinog. Risks Hum. 73: 223-276, 1999.
    • Pohanish, R.P. (editor): Dichlorobenzenes. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 1. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 799-804.
    • Stine, E.R., Gunawardhana, L. and Sipes, I.G.: The acute hepatotoxicity of the isomers of dichlorobenzene in Fischer-344 and Sprague-Dawley rats: isomer specific and strain-specific differential toxicity. Toxicol. Appl. Pharmacol. 109(3): 472-481, 1991.
  • Date Last Revised: 03/28/2007

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):
  • Charcoal Tube (100/50 mg sections, 20/40 mesh)
  • maximum volume: 10 Liters
  • maximum flow rate: 0.2 L/min
  • current analytical method:Gas Chromatography; GC/FID
  • analytical solvent: Carbon Disulfide
  • method reference: OSHA modified NIOSH Analytical Method (NIOSH 1003 (PDF))
  • method classification: Partially Validated

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