
Why does the sea smell like the sea?
Give a lengthy sniff next time you visit the seaside, you will be taking in a variety of scents produced from within the ocean.
Asked by: Aline Smith, London
Saltwater by itself doesn’t have any smell, but the things that live in it certainly do. The rather stale, sulphury smell is dimethyl sulphide, produced by bacteria as they digest dead phytoplankton. At low tide, you’ll also smell chemicals called dictyopterenes, which are sex pheromones produced by seaweed eggs to attract the sperm. And on top of all this is the ‘iodine’ smell of the sea, which is actually the bromophenols produced by marine worms and algae.
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Authors

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
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