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General Description

  • Synonyms: DACPM; 3,3'-Dichloro-4,4'-diaminodiphenylmethane; MBOCA; 4,4'-Methylenebis(o-chloro aniline); 4,4'-Methylenebis(2-chlorobenzenamine); MOCA
  • OSHA IMIS Code Number: 2650
  • Chemical Abstracts Service (CAS) Registry Number: 101-14-4
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: CY1050000
  • NIOSH Pocket Guide to Chemical Hazards, 4,4'-Methylenebis(2-Chloroaniline) chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

  • American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 0.01 ppm, 0.11 mg/m3 TWA; Skin; Appendix A2 - Suspected Human Carcinogen; BEI
  • National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 0.003 mg/m3 TWA; Skin; Appendix A - NIOSH Potential Occupational Carcinogens

Health Factors

  • Carcinogenic Classification:
  • Potential Symptoms: Hematuria (blood in the urine), cyanosis, nausea, methemoglobinemia, headache, dizziness, confusion, convulsions; kidney irritation; [potential occupational carcinogen]
  • Health Effects: Carcinogen (HE1); Mutagen (HE2); Methemoglobinemia (HE13)
  • Affected Organs: Blood, liver, kidneys
  • Notes:
    1. 4,4'-Methylene-bis(2-chloroaniline) (MBOCA) is an OSHA Select Carcinogen without a PEL.
    2. It may be absorbed through the skin and cause a burning sensation.
    3. It has been suggested that measuring urinary MBOCA, perhaps after hydrolysis of a glucuronide conjugate, is a better index of exposure than monitoring airborne MBOCA because of significant skin absorption.
    4. A case of bladder cancer was diagnosed in an employee exposed 14 years during the manufacture of this chemical. Air samples taken two consecutive days in his work area indicated MBOCA concentrations of 0.23 and 0.41 mg/m3.
    5. N-hydroxy- and mononitroso-derivatives of MBOCA, but not MBOCA itself, were reported to produce adducts with rat and human hemoglobin in vitro.
  • Literature Basis:
    • NIOSH Pocket Guide to Chemical Hazards: 4,4'-Methylenebis(2-Chloroaniline).
    • International Chemical Safety Cards (WHO/IPCS/ILO): 4,4'-Methylene bis(2-Chloroaniline).
    • Chen, T.H., Kuslikis, B.I. and Braselton, W.E., Jr.: Unlabeled hemoglobin adducts of 4,4';-methylenebis(2-chloroaniline) in rats and guinea pigs. Arch. Toxicol. 65(3): 177-185, 1991.
    • Cocker, J., Boobie, A.R., Wilson, H.K. and Gompertz, D.: Evidence that a beta-N-glucuronide of 4,4'-methylenebis(2-chloroaniline) (MbOCA) is a major urinary metabolite in man: implications for biological monitoring. Br. J. Ind. Med. 47(3): 154-161, 1990.
    • Ichikawa, Y., Yoshida, M., Okayama, A., Hara, I. and Morimoto, K.: Biological monitoring for workers exposed to 4,4'-methylenebis(2-chloroaniline). Am. Ind. Hyg. Assoc. J. 51(1): 5-7, 1990.
    • Liu, C.-S., et al.: Occupational bladder cancer in a 4,4'-methylenebis(2-chloroaniline) (MBOCA)-exposed worker. Environ. Health Perspec. 113(6): 771-774, 2005.
    • No Author: 4,4'-Methylenebis(2-Chloroaniline) (PDF) (CAS No. 101-14-4). Report on Carcinogens (latest edition); U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program, 2011.
    • Pohanish, R.P. (editor): 4,4'-Methylenebis(2-Chloroaniline). In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1553-1556.
  • Date Last Revised: 09/01/2006

Monitoring Methods used by OSHA

Laboratory Sampling/Analytical Method
  • Coated Glass Fiber Filters (37 mm) in 3 piece cassette. Coating is Sulfuric Acid.
  • maximum volume: 100 Liters
  • maximum flow rate: 1.0 L/min
  • current analytical method: Gas Chromatography; GC/ECD
  • method reference: OSHA Analytical Method (OSHA 71)
  • method classification: Fully Validated
  • note: Within ten hours after sampling, transfer filter to glass vial containing 2 mL deionized water. Filters may be obtained by OSHA personnel from SLTC.
Wipe Sampling Method:
  • Glass Fiber Filter
  • note: Place the wipe sample into a glass vial containing 2 mL of 0.01 N Sulfuric Acid.
Bulk Method:
  • Limit the amount of bulk submitted to one gram or one mL.

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