Gas toxicity

Last updated: March 24, 2023

Summarytoggle arrow icon

Poisoning with toxic gases most commonly occurs in the household and industrial workplace setting with potentially life-threatening consequences. Only the most common sources of gas poisoning are discussed here (with the exception of vinyl chloride, which is discussed under “Polyvinyl Chloride” in “Organic solvent toxicity”). Ammonia is a gas that occurs naturally in the human body but also has a variety of industrial and household uses (e.g., cleaning products); exposure can lead to cough, eye irritation, and mucous membrane and skin burns. Hydrogen sulfide can be naturally found in hot springs and volcanos but also has a variety of industrial and household uses (e.g., cleaning products); exposure can lead to conjunctivitis, headache, fatigue, and, in high concentrations, to life-threatening cardiovascular events. Chlorine is used as a disinfectant as well as cleaning and bleaching agent; exposure can lead to respiratory distress and irritation of the mucous membranes and the autonomic nervous system. Nitrogen oxides develop mainly in the process of organic matter decomposition and engine exhausts; exposure can lead to cough, nausea, and, eventually, to chemical pneumonia and bronchiolitis obliterans. Phosgene occurs in pesticides and plastic production processes; exposure can lead to lacrimation, cough, and respiratory distress. Phosphine is a common component of pesticides; exposure can lead to nausea, paresthesis, respiratory distress, and cardiac shock. Ozone is a natural component of the atmosphere that is toxic at high concentrations, e.g., due to environmental pollution and chemical water purification; exposure can cause sore throat and cough, potentially exacerbating respiratory conditions such as asthma and COPD. Hydrofluoric acid occurs in the production of aluminum and in cleaning products; exposure can lead to life-threatening skin, eye, and mucous membrane burns. Radon is a radioactive gas that occurs naturally in the ground and may accumulate in confined spaces; it is one of the main causes of lung cancer in nonsmokers. In the event of exposure to any toxic gas, the source of toxic gas should be addressed and affected individuals removed from the area immediately; clothing should be decontaminated if necessary. O2 administration and supportive measures (e.g., support of airway, breathing, or circulation) should be provided as necessary depending on the situation.

Ammonia (NH₃)toggle arrow icon

  • Characteristics: colorless, irritant, pungent smell, highly water-soluble (creation of ions: NH+)
  • Sources of exposure


Hydrogen sulfidetoggle arrow icon


Chlorinetoggle arrow icon


Nitrogen oxides (e.g., NO, NO₂)toggle arrow icon


Phosgenetoggle arrow icon


Phosphinetoggle arrow icon


Ozone (O₃)toggle arrow icon


Hydrogen fluoride (hydrofluoric acid)toggle arrow icon


Radontoggle arrow icon

  • Characteristics: highly radioactive, colorless, odorless
  • Sources of exposure: natural environment
    • Radon is produced by the radioactive decay of radium-226, which occurs naturally in rock and soil.
    • May accumulate to hazardous levels in basements and other confined spaces within the home
  • Pathophysiology: emission of α-, β-, and γ-particles, and x-rays → cytotoxicity and DNA damage
  • Clinical features
  • Diagnostics: For further information, see “Diagnostics” in “Lung cancer.”
  • Treatment: For further information, see “Treatment” in “Lung cancer.”
  • Prevention
    • Suctioning radon from rooms and basements (e.g., soil suctioning)
    • Ventilation of rooms and basements
    • Sealing basement cracks


Referencestoggle arrow icon

  1. Morim A, Guldner GT. Chlorine Gas Toxicity. StatPearls. 2021.
  2. Padappayil RP, Borger J. Ammonia Toxicity. StatPearls. 2021.
  3. Swanson TJ, Jamal Z, Chapman J. Ozone Toxicity. StatPearls. 2021.
  4. Vaish AK, Consul S, Agrawal A, et al. Accidental phosgene gas exposure: A review with background study of 10 cases.. Journal of emergencies, trauma, and shock. 2013; 6 (4): p.271-5.doi: 10.4103/0974-2700.120372 . | Open in Read by QxMD
  5. Sciuto AM, Wong BJ, Martens ME, Hoard-Fruchey H, Perkins MW. Phosphine toxicity: a story of disrupted mitochondrial metabolism. Ann N Y Acad Sci. 2016; 1374 (1): p.41-51.doi: 10.1111/nyas.13081 . | Open in Read by QxMD
  6. Eidy M, Tishkowski K. Radon Toxicity. StatPearls. 2021.
  7. Sawaya A, Menezes RG. Hydrogen Sulfide Toxicity. StatPearls. 2021.
  8. Amaducci A, Downs JW. Nitrogen Dioxide Toxicity. StatPearls. 2021.
  9. Bajraktarova-Valjakova E, Korunoska-Stevkovska V, Georgieva S, et al. Hydrofluoric Acid: Burns and Systemic Toxicity, Protective Measures, Immediate and Hospital Medical Treatment. Open Access Macedonian Journal of Medical Sciences. 2018; 6 (11): p.2257-2269.doi: 10.3889/oamjms.2018.429 . | Open in Read by QxMD

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