Waves lapping the beaches of southern Finistère turned an unusual shade orange at the weekend - but there is nothing to worry about, authorities have said.
Officials banned anyone from entering the sea for several hours on Saturday at Trégunc, Moëlan-sur-Mer and Clohars-Carnoët because of the strange colour of the water in several sections of beaches.
But investigations have confirmed that the effect has been caused by a perfectly natural phenomenon - a bloom of the phytoplankton Noctiluca scintillans.
The orange water may appear on beaches along the coast of neighbouring Morbihan in days to come. In a statement, a spokesperson for the prefecture said: "On the Breton coasts, the proliferation of phytoplankton does not present any particular danger for bathing activity."
But officials have issued the following advice.
- Do not swim in areas of algae accumulation.
- Take a shower after swimming.
- Stop children ingesting seawater.
- Avoid walking on areas with phytoplankton deposits due to a risk of falling.
- Do not eat shellfish, crustaceans and dead fish.
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