The farmer’s body was found in the Bay of Morlaix (Finistère) on July 6. He is suspected to have died from inhalation of toxic gases released by the green algae in the surrounding area.
Authorities in Brest have ordered an autopsy on the man, to determine his exact cause of death.
Jean-Philippe Récapé, prosecutor for la République de Brest, told the Agence France-Presse: “The body was driven to the hospital and examinations were done. The man had previously appeared to be in good health.”
Local environmental associations have recently seen a sharp increase in the proliferation of green algae in the area. The groups Sauvegarde du Trégor and Halte aux Marées Vertes have both suggested that “intoxication from hydrogen sulfide” - a potentially-fatal gas emitted by algae as it decomposes - may have caused the man’s death.
They said that after an inspection of the bay, they had “discovered a vast, muddy area covered by a layer of green algae”.
They asked: “How can you not draw a link between this abnormal growth of algae in these areas, with the River Frout, which opens into the bay, and in which we measured a level of 53mg/l of nitrates?” High levels of nitrates, usually from agriculture, can encourage algae to grow and become what are dubbed “green tides”, especially in warm weather.
This is not the first death that has been linked to green algae, and fears over the build up of the organisms in Brittany have risen in recent years.
In 2009, a 48-year-old man died after driving a van full of green algae in Côtes-d’Armor, and coming into close and prolonged proximity with the plants. Nine years later, a court in Saint-Brieuc admitted to his family that the algae had been dangerous.
In 2014, the State admitted responsibility for the death of a horse due to decomposition of green algae on a beach, again in Côtes-d’Armor in 2009.
The administrative court in Nantes linked “the proliferation of green algae” with “a lack of sufficient national and European rules” around the protection of water from “pollution from farming” - the main cause of high green algae growth.
In 2016, a man died suddenly while out jogging on the Hillion coast, again in Côtes-d’Armor. A link with green algae was suspected a further time. However, an autopsy revealed no definite conclusions, with the inquiry closing the case in April 2017.
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