GREEN tides of potentially toxic seaweed that have clogged up several beaches in Brittany appear to have spread to neighbouring Normandy, threatening the D-Day landing heritage beaches.
Local officials at Grandcamp-Maisy, on the Calvados coast between Utah Beach and Omaha Beach, are concerned about the growing quantities of seaweed being washed up on the shore this summer.
The commune has collected 5,000 tonnes of seaweed so far this year - about 60% of which were green algae similar to those found on the north coast of Brittany.
Algae watchdog Ceva says Normandy could face similar problems to those seen in Brittany, where several beaches have been closed because of toxic fumes from the rotten seaweed.
Unlike in Brittany, where intensive pig farming has been blamed, the problem in Normandy could be linked to waste from stables that makes its way into the water. Farmers have been urged to cut their use of pesticides, which has also been linked to the proliferation of algae.
There are also reports of the problem spreading to Saint-Nazaire, on the Atlantic coast, which was closed last Friday.
Seaweed is naturally present on northern French beaches and poses no threat to public health when it is freshly washed up.
However, the algae on parts of the Brittany coast has mixed with nitrogen-rich waste in the sea and, when it rots in the sun, gives off hydrogen sulphide, a noxious gas with a foul smell.
The seaweed issue first caught national attention in 2009 when a horse died and its owner fell unconscious after breathing fumes at the beach in Saint-Michel-en-Grève.
About 30 wild boar were found dead on Brittany beaches earlier this summer - all believed to be linked to the fumes from the seaweed.
Stock photo: innacoz/Flickr