# Is ground level ozone dangerous to human health when other pollutants are not present, for example, at high altitudes?

In mountainous areas there is often little or no air pollution such as particulate matter, sulphur/nitrogen dioxide etc. However, ground-level ozone is frequently more present at these higher altitudes. For example, in the Pyrenees mountains between France and Spain there is little or no pollution however they show high ozone readings. The Alps show the same situation.

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• This would seem to be asking about Biology, rather than about earth science. – EnergyNumbers Jun 15 '14 at 20:03