| MadSci Network: General Biology |
Nihal, You're correct - oxygen is necessary for life, but it's also important what form it comes in. Diatomic atmospheric oxygen is very stable and is unlikely to react vigorously with most materials: it takes a moderate amount of energy to split the bonds between the two atoms in the molecule and make them available for your body's metabolic processes. Ozone, however, is very unstable: the molecule tends to decompose uncontrolledly and spontaneously and into diatomic oxygen and a free oxygen atom. Free oxygen is very reactive and will tend to oxidize and chemically burn anything it touches, including your nose, throat and lungs. The US Environmental protection agency and the chemistry department at the University of Wisconsin have further information on how ozone is created in the atmosphere and what its health effects are.
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