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Record Information
Creation Date2014-09-11 05:13:38 UTC
Update Date2014-12-24 20:26:56 UTC
Accession NumberT3D4725
Common NameOzone
ClassSmall Molecule
DescriptionOzone is a pale blue gas with a distinctively pungent smell. Ozone is formed from dioxygen by the action of ultraviolet light and also atmospheric electrical discharges. It is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 ppm of the atmosphere. In standard conditions, ozone is a pale blue gas that condenses at progressively cryogenic temperatures to a dark blue liquid and finally a violet-black solid. Ozone is a powerful oxidant (far more so than oxygen gas) and has many industrial and consumer applications related to oxidation. This same high oxidizing potential, however, causes ozone to damage mucus and respiratory tissues in animals, and also tissues in plants, above concentrations of about 100 ppb. Ozone's odor is sharp, reminiscent of chlorine, and detectable by many people at concentrations of as little as 10 ppb in air. Ozone, along with reactive forms of oxygen such as superoxide, singlet oxygen, hydrogen peroxide, and hypochlorite ions, is naturally produced by white blood cells. The largest use of ozone is in the preparation of pharmaceuticals, synthetic lubricants, and many other commercially useful organic compounds. It can also be used for bleaching substances and for killing microorganisms in air and water sources. Many municipal drinking water systems kill bacteria with ozone instead of the more common chlorine.
Compound Type
  • Food Toxin
  • Industrial/Workplace Toxin
  • Inorganic Compound
  • Lachrymator
  • Metabolite
  • Natural Compound
Chemical Structure
Oxygen, mol (O3)
Ozone heavy work
Ozone heavy, moderate, or light workloads (<2 hours)
Ozone light work
Ozone moderate work
Ozone, 11CI
Triatomic oxygen
Chemical FormulaO3
Average Molecular Mass47.998 g/mol
Monoisotopic Mass47.985 g/mol
CAS Registry Number10028-15-6
IUPAC Nametrioxirane
Traditional Namecyclic ozone
InChI IdentifierInChI=1S/O3/c1-2-3-1
Chemical Taxonomy
Description belongs to the class of inorganic compounds known as other non-metal oxides. These are inorganic compounds containing an oxygen atom of an oxidation state of -2, in which the heaviest atom bonded to the oxygen belongs to the class of 'other non-metals'.
KingdomInorganic compounds
Super ClassHomogeneous non-metal compounds
ClassOther non-metal organides
Sub ClassOther non-metal oxides
Direct ParentOther non-metal oxides
Alternative ParentsNot Available
  • Other non-metal oxide
Molecular FrameworkNot Available
External DescriptorsNot Available
Biological Properties
StatusDetected and Not Quantified
OriginEndogenous and Exogenous
Cellular Locations
  • Extracellular
Biofluid LocationsNot Available
Tissue Locations
  • Lung
  • Nasal Passages
PathwaysNot Available
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
AppearanceLight blue gas.
Experimental Properties
Melting Point-251 °C
Boiling PointNot Available
SolubilityNot Available
LogPNot Available
Predicted Properties
pKa (Strongest Basic)-6.2ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area34.29 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity4.05 m³·mol⁻¹ChemAxon
Polarizability2.22 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot AvailableJSpectraViewer
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot AvailableJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0002-9000000000-be30dca12c52c2bb5f3aJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0002-9000000000-be30dca12c52c2bb5f3aJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0002-9000000000-be30dca12c52c2bb5f3aJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0002-9000000000-60959792246836c9582eJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0002-9000000000-60959792246836c9582eJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0002-9000000000-60959792246836c9582eJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0002-9000000000-ebe7a0b0fb1a1236ce9fJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0002-9000000000-ebe7a0b0fb1a1236ce9fJSpectraViewer
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0002-9000000000-ebe7a0b0fb1a1236ce9fJSpectraViewer
Toxicity Profile
Route of ExposureInhalation
Mechanism of ToxicityOzone is a strong oxidant and reacts directly with organic double bonds. When ozone breaks down to dioxygen it gives rise to oxygen free radicals, which are highly reactive and capable of damaging many organic molecules. Moreover, it is believed that the powerful oxidizing properties of ozone may be a contributing factor of inflammation. When inhaled, ozone reacts with compounds lining the lungs to form specific, cholesterol-derived metabolites that are thought to facilitate the build-up and pathogenesis of atherosclerotic plaques. These metabolites have been confirmed as naturally occurring in human atherosclerotic arteries and are categorized into a class of secosterols termed atheronals, generated by ozonolysis of cholesterol's double bond to form a 5,6 secosterol. Ozone has also been shown to form the suspected carcinogen bromate when it is introduced to source water with high bromide concentrations. Studies have also demonstrated an increase in collagen, a structural protein involved in fibrosis, following prolonged ozone exposure. Acute and short-term exposure studies have demonstrated ozone’s effects on lung lipids which include an increase in arachidonic acid (a pro-inflammatory molecule).
MetabolismOzone can spontaneously break down to dioxygen. Most inhaled ozone reacts with cellular lipids and forms lipid peroxides which are eventually eliminated in the feces.
Toxicity Values0.1 to 1 umol/mol will cause acute toxic effects. 40 nmol/mol will cause long term lung problems. Pulmonary edema developed in welders who had a severe acute exposure to an estimated 9 ppm ozone plus other air pollutants.
Lethal Dose50 ppm for 60 minutes is expected to be fatal to humans.
Carcinogenicity (IARC Classification)No indication of carcinogenicity (not listed by IARC) (9). Tests in mice found no carcinogenic effect (7).
Uses/SourcesProduced by white blood cells, generated by lightning, photocopiers and UV light. Used as an industrial chemical in the preparation of pharmaceuticals, synthetic lubricants. Used for bleaching and as a disinfectant.
Minimum Risk LevelSusceptible people can be adversely affected by ozone levels as low as 40 nmol/mol. In the EU, the current target value for ozone concentrations is 120 µg/m³ which is about 60 nmol/mol. In the US the recommended EPA standard is 75 nmol/mol.
Health EffectsAt acute levels, ozone is an irritant and lachrymator. At chronically low doses (~40 nmol/mol) there is a great deal of evidence to show that ground level ozone can harm lung function and irritate the respiratory system. Long-term exposure to ozone and the pollutants that produce it is linked to premature death, asthma, bronchitis, heart attacks and other cardiopulmonary problems. Long-term exposure to ozone has been shown to increase risk of death from respiratory illness. An 18-year study on 450,000 people in the US revealed that those living in cities with high ozone levels such as Houston or Los Angeles had an over 30% increased risk of dying from lung disease. Both acute and chronic exposures to ozone can negatively impact the barrier function of the lung, and these exposures can initiate an inflammatory response from the immune system. This immune response involves the release of biologically active mediators that can have adverse effects on the lung tissue itself. Some effects may include the thickening of the air-blood barrier in the lungs, thus reducing the diffusion of oxygen into the blood. Animals exposed to ozone produce and release high amounts of a sugar known as hyaluronan. Hyaluronan has been shown to be directly responsible for causing lung airways to narrow and become irritated. (6)
SymptomsExposure of 0.1 to 1 μmol/mol produces headaches, burning eyes and irritation to the respiratory passages. Exposure to 10 ppm ozone will cause pulmonary edema. Low doses act as a depressant and will induce sleep in certain individuals.
TreatmentEYES: Hold eye open and rinse slowly and gently with water for 15-20 minutes. Remove contact lenses, if present, after the first 5 minutes, then continue rinsing eye. Call a poison control center or doctor for treatment advice. INHALATION: Move person to fresh air. If person is not breathing, call 911 or an ambulance, then give artificial respiration, preferably by mouth-to-mouth if possible. Call a poison control center or doctor for further treatment advice.
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
PubChem Compound ID16206854
ChEMBL IDNot Available
ChemSpider ID13375217
KEGG IDNot Available
UniProt IDNot Available
ChEBI ID25812
BioCyc IDNot Available
CTD IDNot Available
Stitch IDNot Available
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkNot Available
Synthesis ReferenceNot Available
General References
  1. Travagli V, Zanardi I, Bocci V: Topical applications of ozone and ozonated oils as anti-infective agents: an insight into the patent claims. Recent Pat Antiinfect Drug Discov. 2009 Jun;4(2):130-42. [19519548 ]
  2. Shakov VIu, Edeleva AN: [Reasons for the application of medical ozone in the treatment of chronic purulent mesotympanitis]. Vestn Otorinolaringol. 1999;(2):48-9. [10226494 ]
  3. Zuma FN, Lin J, Jonnalagadda SB: Kinetics of inactivation of Pseudomonas aeruginosa in aqueous solutions by ozone aeration. J Environ Sci Health A Tox Hazard Subst Environ Eng. 2009 Aug;44(10):929-35. [19827485 ]
  4. Wells KH, Latino J, Gavalchin J, Poiesz BJ: Inactivation of human immunodeficiency virus type 1 by ozone in vitro. Blood. 1991 Oct 1;78(7):1882-90. [1717074 ]
  5. Clayton H, Knight MR, Knight H, McAinsh MR, Hetherington AM: Dissection of the ozone-induced calcium signature. Plant J. 1999 Mar;17(5):575-9. [10205911 ]
  6. Garantziotis S, Li Z, Potts EN, Kimata K, Zhuo L, Morgan DL, Savani RC, Noble PW, Foster WM, Schwartz DA, Hollingsworth JW. Hyaluronan mediates ozone-induced airway hyperresponsiveness in mice. J Biol Chem. 2009 Apr 24;284(17):11309-17. doi: 10.1074/jbc.M802400200. Epub 2009 Jan 21. [19164299 ]
  7. Witschi H, Espiritu I, Pinkerton KE, Murphy K, Maronpot RR: Ozone carcinogenesis revisited. Toxicol Sci. 1999 Dec;52(2):162-7. [10630568 ]
  8. Yannai, Shmuel. (2004) Dictionary of food compounds with CD-ROM: Additives, flavors, and ingredients. Boca Raton: Chapman & Hall/CRC.
  9. International Agency for Research on Cancer (2014). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. [Link]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available


General Function:
Temperature-gated cation channel activity
Specific Function:
Receptor-activated non-selective cation channel involved in detection of pain and possibly also in cold perception and inner ear function (PubMed:25389312, PubMed:25855297). Has a central role in the pain response to endogenous inflammatory mediators and to a diverse array of volatile irritants, such as mustard oil, cinnamaldehyde, garlic and acrolein, an irritant from tears gas and vehicule exhaust fumes (PubMed:25389312, PubMed:20547126). Is also activated by menthol (in vitro)(PubMed:25389312). Acts also as a ionotropic cannabinoid receptor by being activated by delta(9)-tetrahydrocannabinol (THC), the psychoactive component of marijuana (PubMed:25389312). May be a component for the mechanosensitive transduction channel of hair cells in inner ear, thereby participating in the perception of sounds. Probably operated by a phosphatidylinositol second messenger system (By similarity).
Gene Name:
Uniprot ID:
Molecular Weight:
127499.88 Da
  1. Nilius B, Prenen J, Owsianik G: Irritating channels: the case of TRPA1. J Physiol. 2011 Apr 1;589(Pt 7):1543-9. doi: 10.1113/jphysiol.2010.200717. Epub 2010 Nov 15. [21078588 ]