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Nitrogen Trichloride

General Description

  • Synonyms: Agene; Chlorine nitride; Trichloramine; Trichlorine nitride
  • OSHA IMIS Code Number: N120
  • Chemical Abstracts Service (CAS) Registry Number: 10025-85-1
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: QW974000
  • Department of Transportation Regulation Number (49 CFR 172.101) and Emergency Response Guidebook: Forbidden
  • Chemical Description and Physical Properties: Yellow oily liquid with pungent odor; does not mix with water. Soluble in chloroform, phosphorus trichloride, carbon disulfide. Decomposes in light, and in water in 24 hours. Forms bleaching liquor and ammonia in hot water.
    • molecular formula: Cl3N
    • molecular weight: 120.36
    • boiling point: 71°C
    • vapor pressure: 19.95 @ 25°C
    • melting point: -40°C
  • Potentially hazardous incompatibilities: May decompose violently or explosively on contact with other substances.

Health Factors

  • Potential symptoms: Eye, nose, throat irritation; sneezing, cough, wheezing, chest tightness, dyspnea (difficulty breathing); headache.
  • Health Effects: Irritation-Eyes, Nose, Throat (HE16); Suspected respiratory sensitization---asthma (HE9)
  • Affected organs: Eyes, respiratory system
  • Notes:
    1. Occupational exposure can occur in food-processing plants (Hery et al., 1998 and 1999; Massin et al., 2007), including those with USDA inspectors (King et al., 2006; Sanderson et al., 1995), and in indoor swimming pool areas (Hery et al., 1995; Massin et al., 1998; Nemery et al., 2002; Thickett et al., 2002). Recreational or athletic swimmers may also be exposed at indoor swimming pools (Penny, 1983; Carbonnelle et al., 2002; Bernard et al., 2003).
    2. Nitrogen trichloride reacts with the amino acid methionine to form methionine sulfoximine, which has been reported to have excitotoxic actions in experiments with rat brain tissue (Shaw et al., 1999).
    3. The LC50 for a 1-hour exposure in rats is 112 ppm (Barbee et al., 1983).
    4. Based upon upper airway irritation studies in mice, Gagnaire et al. (1994) in France recommended a TLV-TWA of 0.1 ppm and a TLV-STEL of 0.3 ppm.
    5. Nitrogen trichloride may be formed in small amounts during the process of disinfecting public water systems with monochloramine, produced by combining chlorine or hypochlorite and ammonia - a process now used in approximately 20% of U.S. public water systems (Skipton and Dvorak, 2002).
    6. Pure nitrogen trichloride is very unstable and can explode violently "upon contact with organic chemicals or catalytic surfaces, by impact, by supersonic sound waves (shock waves), or simply by selfheating due to the decomposition reactions." (Dokter, 1985).
  • Literature Basis:
    • Barbee, S.J., Thackara, J.W. and Rinehart, W.E.: Acute inhalation toxicology of nitrogen trichloride. Am. Ind. Hyg. Assoc. J. 44(2): 145-146, 1983.
    • Bernard, A., Carbonnelle, S., Michel, O., Higuet, S., De Burbure, C., Buchet, J.P., Hermans, C., Dumont, X. and Doyle, I.: Lung hyperpermeability and asthma prevalence in schoolchildren: unexpected associations with the attendance at indoor chlorinated swimming pools. Occup. Environ. Med. 60(6): 385-394, 2003.
    • Carbonnelle, S., Francaux, M., Doyle, I., Dumont, X., de Burbure, C., Morel, G., Michel, O. and Bernard, A.: Changes in serum pneumoproteins caused by short-term-exposure to nitrogen trichloride in indoor chlorinated swimming pools. Biomarkers 7(6): 464-478, 2002.
    • Dokter, T.: Formation of NCl3 and N2O in the reaction of NaOCl and nitrogen compounds. J. Hazard. Mater. 12: 207-224, 1985.
    • Gagnaire, F., Azim, S., Bonnet, P., Hecht, G. and Hery, M.: Comparison of the sensory irritation response in mice to chlorine and nitrogen trichloride. J. Appl. Toxicol. 14(6): 405-409, 1994.
    • Hery, M., Gerber, J.M., Hecht, G., Subra, I., Possoz, C., Aubert, S., Dieudonne, M. and Andre, J.C.: Exposure to chloramines in a green salad processing plant. Ann. Occup. Hyg. 42: 437-451, 1998.
    • Hery, M., Hecht, G., Gerber, J.M., Hubert, G., Subra, I., Aubert, S., Gerardin, F. and Dorotte, M.: Occupational exposure during cleaning and disinfection in the food industry. Occup. Hyg. 5(2): 131-144, 1999.
    • Hery, M., Hecht, G., Gerber, J.M., Gendre, J.C., Hubert G. and Rebuffaud, J.: Exposure to chloramines in the atmosphere of indoor swimming pools. Ann. Occup. Hyg. 39: 427-439, 1995.
    • King, B.S., Page, E.H., Mueller, C.A., Dollberg, D.D., Gomez, K.E. and Warren, A.M.: Eye and respiratory symptoms in poultry processing workers exposed to chlorine by-products. Am. J. Ind. Med. 49(2): 119-126, 2006.
    • Massin, N., Bohadana, A.B., Wild, P., Mery, M., Toamain, J.P. and Hubert, G.: Respiratory symptoms and bronchial responsiveness in lifeguards exposed to nitrogen trichloride in indoor swimming pools. Occup. Environ. Med. 55: 258-263, 1998.
    • Massin, N., et al.: Respiratory symptoms and bronchial responsiveness among cleaning and disinfecting workers in the food industry. Occup. Environ. Med. 64(2): 75-81, 2007.
    • Nemery, B., Hoet, P.H.M. and Nowak, D.: Indoor swimming pools, water chlorination and respiratory health (editorial). Eur. Respir. J. 19(5): 790-793, 2002.
    • Penny, P.T.: Swimming pool wheezing. Br. Med. J. (Clin. Res. Ed.) 287(6390): 461-462, 1983.
    • Sanderson, W.T., Weber, A. and Echt, A.: Case reports: epidemic eye and upper respiratory irritation in poultry processing plants. Appl. Occup. Environ. Hyg. 10(1): 43-49, 1995.
    • Shaw, C.A., Bains, J.S., Pasqualotto, B.A. and Curry, K.: Methionine sulfoximine shows excitotoxic actions in rat cortical slices. Can. J. Physiol. Pharmacol. 77(11): 871-877, 1999.
    • Skipton, S. and Dvorak, B.: Drinking water: chloramines water disinfection in Omaha Metropolitan Utilities District. Nebraska Cooperative Extension File NF02-505, 2002.
    • Thickett, K.M., McCoach, J.S., Gerber, J.M., Sadhra, S. and Burge, P.S.: Occupational asthma caused by chloramines in indoor swimming-pool air. Eur. Respir. J. 19(5): 827-832, 2002.
  • Date Last Revised: 05/23/2007

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