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General Description

  • Synonyms: Butylamine, N-Nitrosodi; N-Butyl-N-nitroso-1-butamine; DBN; DBNA; Dibutylamine, N-Nitroso; Dibutylnitrosamine; Di-n-butylnitrosamine; N,N-Di-n-butylnitrosamine; NDBA; N-Nitroso-di-n-butylamine
  • OSHA IMIS Code Number: 1944
  • Chemical Abstracts Service (CAS) Registry Number: 924-16-3
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: EJ4025000
  • Chemical Description and Physical Properties:
    • pale yellow oil with characteristic odor
    • molecular formula: C8H18N2O
    • molecular weight: 158.24
    • boiling point: 116°C/14 mm Hg

Health Factors

  • Carcinogenic Classification:
  • Potential Symptoms: Irritation of eyes, skin; in animals: liver damage; [potential occupational carcinogen]
  • Health Effects: Animal carcinogen (urinary bladder and multiple other sites) (HE2)
  • Affected Organs: Urinary bladder, esophagus, liver
  • Notes:
    1. N-Nitrosodibutylamine is an OSHA Select Carcinogen. OSHA does not have a PEL for this chemical.
    2. Two major metabolites of this chemical, N-nitroso-n-butyl-N-(4-hydroxybutyl)amine and N-nitroso-n-butyl-N-(3-carboxypropyl) amine also cause bladder cancer in animals.
    3. Incubation of N-nitrosodibutylamine at a high concentration (4 mM) with human liver microsomes resulted in rates of production of the four metabolites, N-nitroso-n-butyl-N-(4-hydroxybutyl)amine N-nitroso-n-butyl-N-(3-hydroxybutyl)amine N-nitroso-n-butyl-N-(2-hydroxybutyl)amine and butyraldehyde in the approximate ratios of 1:13:4:1, respectively.
    4. N-Nitrosodibutylamine has been found in gastric juice and may be found in some foods and rubber products exposed to nitrite during production or utilization.
  • Literature Basis:
    • U.S. EPA Integrated Risk Information System: N-Nitroso-di-n-butylamine (CASRN 924-16-3).
    • No Author: N-Nitrosodi-n-Butylamine, CAS No. 924-16-3. Report on Carcinogens (latest edition); U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program, 2005.
    • Bellec, G., Dréano, Y., Bail, J.-P., Ménez, J.-F. and Berthou, F.: Cytochrome P450 hydroxylation of carbon atoms of the alkyl chain of symmetrical N-nitrosodialkylamines by human liver microsomes. Mutat. Res. 377(2): 199-209, 1997.
    • Dallinga, J.W., et al.: Volatile N-nitrosamines in gastric juice of patients with various conditions of the gastrointestinal tract determined by gas chromatography-mass spectrometry and related to intragastric pH and nitrate and nitrite levels. Cancer Lett. 124(2): 119-125, 1998.
    • Fiddler, W., Pensabene, J., Sphon, J. and Andrzejewski. D.: Nitrosamines in rubber bands used for orthodontic purposes. Food Chem. Toxicol. 30(4): 325-326, 1992.
    • Heenan, M.P., Nacey, J.N., Delahunt, B., Ferguson, A.F. and Dickson, S.J.: Volatile N-nitrosamines in urinary catheters. Br. J. Urol. 63(1): 72-75, 1989.
    • Pohanish, R.P. (editor): N-Nitrosodi-n-Butylamine. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1728-1730.
  • Date Last Revised: 06/06/2006

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):
  • ThermoSorb/N Tube
  • maximum volume: 75 Liters
  • maximum flow rate: 1.0 L/min
  • current analytical method: Gas Chromatography; GC/TEA
  • analytical solvent: (75:25) Dichloromethane:Methanol
  • method reference: OSHA Analytical Method (OSHA 27)
  • method classification: Fully Validated
  • note: OSHA personnel may obtain ThermoSorb/N Tube from the Salt Lake Technical Center (SLTC). Store samples in freezer.
Bulk Method:
  • Limit the amount of bulk submitted to one gram or one mL.

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