Case Definition: Ammonia

Clinical description

The majority of exposures occur by inhalation and typically lead to symptoms of ocular, nasal, and respiratory irritation. Signs and symptoms of poisoning might include eye redness and lacrimation, nose and throat irritation, cough, suffocation or choking sensation, and dyspnea (1-3).
Laboratory criteria for diagnosis

  • Biologic: No biologic marker is readily available for ammonia exposure or poisoning.
  • Environmental: Detection of ammonia in environmental samples.

Case classification

  • Suspected: A case in which a potentially exposed person is being evaluated by health-care workers or public health officials for poisoning by a particular chemical agent, but no specific credible threat exists.
  • Probable: A clinically compatible case in which a high index of suspicion (credible threat or patient history regarding location and time) exists for ammonia exposure, or an epidemiologic link exists between this case and a laboratory-confirmed case.
  • Confirmed: A clinically compatible case in which laboratory tests of environmental samples have confirmed exposure.

The case can be confirmed if laboratory testing was not performed because either a predominant amount of clinical and nonspecific laboratory evidence of a particular chemical was present or the etiology of the agent is known with 100% certainty.

Additional resources

  1. Nelson LS, Odujebe OA. Chapter 124. Simple Asphyxiants and Pulmonary Irritants. In: Hoffman RS, Nelson LS, Goldfrank LR, Howland MA, Lewin NA, Flomenbaum NE, eds. Goldfrank’s Toxicologic Emergencies. 9th ed. New York: McGraw-Hill; 2011.
  2. Ellenhorn MJ, Schonwald S, Ordog G, Wasserberger J, eds. Respiratory toxicology. In: Ellenhorn’s medical toxicology: diagnosis and treatment of human poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins; 1996:1448-531.
  3. Agency for Toxic Substances and Disease Registry. Toxicological profile for ammonia. Atlanta, GA: Agency for Toxic Substances and Disease Registry, Division of Toxicology; 2002.
  4. Eduard W, Pearce N, Douwes J. Chronic bronchitis, COPD, and lung function in farmers: the role of biological agents. Chest. 2009;136(3):716-25
  5. NIOSH. NIOSH manual of analytical methods [online]. 2003. [cited 2013 Apr 5]. Available from URL:
  6. OSHA. Sampling and analytical methods [online]. 2010. [cited 2013 Apr 5]. Available from URL: icon.
  7. FDA. Food: Laboratory methods [online]. 2013. [cited 2013 Apr 5]. Available from URL: icon.
  8. EPA. Selected analytical methods: chemical methods query [online]. 2013. [cited 2013 Apr 5]. Available from URL: icon.
Page last reviewed: April 4, 2018