Oxygen

:This article is about the chemical element oxygen. For other usage, see Oxygen (disambiguation).

Precautions

Oxygen can be toxic at elevated partial pressures. This is important in some forms of scuba diving, such as with a rebreather.

Related Topics:
Toxic - Partial pressure - Scuba - Rebreather

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Certain derivatives of oxygen, such as ozone (O3), singlet oxygen, hydrogen peroxide, hydroxyl radicals and superoxide, are also highly toxic. The body has developed mechanisms to protect against these toxic species. For instance, the naturally-occurring glutathione can act as an antioxidant, as can bilirubin which is normally a breakdown product of hemoglobin. Highly concentrated sources of oxygen promote rapid combustion and therefore are fire and explosion hazards in the presence of fuels. This is true as well of compounds of oxygen such as chlorates, perchlorates, dichromates, etc. Compounds with a high oxidative potential can often cause chemical burns.

Related Topics:
Ozone - Singlet oxygen - Hydrogen peroxide - Hydroxyl radical - Superoxide - Combustion - Fire - Explosion - Fuel - Burns

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The fire that killed the Apollo 1 crew on a test launchpad spread so rapidly because the pure oxygen atmosphere was at normal atmospheric pressure instead of the one third pressure that would be used during an actual launch. (See partial pressure.)

Related Topics:
Apollo 1 - Partial pressure

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Oxygen derivatives are prone to form free radicals, especially in metabolic processes. Because they can cause severe damage to cells and their DNA, they are thought to be related to cancer and aging.

Related Topics:
Free radicals - DNA

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