Asked by: Jan Darke, Eastbourne
It isn't, particularly. In Victorian England, seaside resorts acquired a reputation for the health-giving qualities of the air but this may just have been relative to the distinctly unhealthy city smogs of the time. Certainly, the idea that ozone or iodine might be inhaled in physiologically significant concentrations is unfounded. In fact, the unique 'bracing' smell of the seaside is caused by dimethyl sulphide produced by coastal bacteria. This isn't particularly good for you but it is generally present in very low concentrations. However a study last year found that sea salt can react with chemicals in marine exhaust fumes to actually worsen atmospheric pollution. So the air around a busy port may be even less healthy than in a city.
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