What is the toxicity of oxygen?

Oxygen toxicity is the condition that occurs when one breathes too much pure oxygen. Breathable air is about 21 percent oxygen; The rest consists of nitrogen and many other substances. When molecular oxygen or _{2 is inhaled in a higher proportion, various symptoms may occur, including vision of tunnels, nausea and airway inflammation. Different forms of oxygen toxicity may be the result of different forms of exposure to elevated oxygen levels. Damage to the central nervous system tends to result in high -pressure and short exposure to elevated oxygen levels, while longer -term exposure to elevated oxygen levels at normal atmospheric pressure tends to lead to lung or eye problems.}

The oxygen toxicity of the central nervous system tends to occur only at high pressure, so it is primarily a problem for divers and others who spend time in conditions higher than atmospheric pressure. When the diver progresses deeper into the water, partial pressureYny in its tank increases in relation to its depth. Thus, the toxicity of the oxygen of the central nervous system is possible at sufficient depth, because the diver breathes oxygen at significantly higher than normal atmospheric pressure. This can lead to a wide range of symptoms, including nausea; dizziness; jerking; And in serious cases, seizures and perhaps death.

oxygen toxicity is still possible at normal atmospheric pressure; This occurs when a fraction of oxygen in the air is significantly higher than normal of approximately 21 percent. Toxicity may occur at 50 % oxygen or higher, although it generally takes some time, usually more than 24 hours before symptoms are manifested. Approximately 100 % oxygen may occur much faster, generally after 14 hours, but sometimes after four hours. Oxygen toxicity that occurs due to long -term exposure to high levels of oxygen at normal atmospheric pressureIn general, it leads to lung symptoms rather than symptoms of the central nervous system. Such symptoms include inflammation of the airways and lungs, cough, difficulty breathing and fever.

A number of chemical mechanisms related to cellular breathing and metabolism are responsible for symptoms associated with oxygen toxicity. While oxygen is necessary for cellular breathing, higher concentrations lead to the production of highly reactive by -products that can cause significant cell damage. Similar highly reactive chemical types enter or are produced regularly by the body, but the body has many systems that are able to prevent or repair the damage that can be caused. Body systems are unable to keep up with the production of these destructive elements in increased oxygen conditions, so oxygen toxicity occurs in the form of cell damage.