French beach toxic enough to kill a horse

SAINT-MICHEL-EN-GRÈVE, France — It should have been a perfect day for Vincent Petit, finishing an afternoon gallop on a wide expanse of beach along a pastel-colored bay. Instead, he and his mount were sucked into a hole of noxious black sludge.

The horse died within seconds, the rider lost consciousness, and a dirty secret on the Brittany coast reverberated across France: decaying green algae was fouling some of its best beaches.

A report ordered by the government after the accident found concentrations of hydrogen-sulfide gas emitted by the rotting algae were as high as 1,000 parts per million on the beach where the horse died, an amount that "can be fatal in several minutes."

There had been signs of a crisis for years in this idyllic corner of Brittany. But scaring away tourists was in no one's interest, including the farming industry — the region's economic backbone — whose nitrate-packed fertilizers power algae blooms.

It took the death of the horse to bring the problem into the open.

Decaying ulva algae threaten other beaches around France and the world, from the United States to China, experts say. Last year, the Chinese government brought in the army to remove the slimy growths so the Olympic sailing competition could be held.

In Brittany's Côte d'Armor region, conditions are perfect for algae's spread: sunlight, shallow waters and flat beaches. Chemical and natural fertilizers such as pig excrement, loaded with nitrates and phosphorous, have saturated the land, spilling into rivers and the ocean, feeding the algae that proliferate.

Harmless while in water, the algae form dangerous gases — notably hydrogen sulfide, with its characteristic rotten-egg smell — when they wash up on land and decay. A white crust forms and traps the gases, which are released when stepped on or otherwise disturbed. Over time, putrefied algae turn sand into black silt muck, sometimes containing pockets of poison gas.

On July 28, Petit, 28, a researcher in a state-run virology lab, had just finished riding his thoroughbred Sir Glitter, a retired racehorse, on the Saint-Michel-en-Grève beach, when the two were mired in muck as he led the horse on foot.

"The horse and I slid in," said Petit, who is also trained in veterinary studies. Petit said he watched as his horse stopped breathing and died within about 30 seconds, and then he himself passed out. Petit was pulled from the mire by a bulldozer shovel after a man who witnessed the accident gave the alert.

While locals are aware of the perils posed by the silt traps that lurk under the sand around streams that feed from the beach into the ocean, Petit did not sense the danger until the ground gave way and he and his horse were sucked into the noxious ooze up to Petit's chest.

Police initially ruled that the horse suffocated, but a necropsy showed the animal died of an acute pulmonary edema with symptoms "compatible with gaseous intoxication in a brutal manner," Petit said, quoting the report, which he paid for.

There have been local efforts to clear the blight. Mayor René Ropartz said Saint-Michel-en-Grève, a village of 480 people, collected 10,000 tons of algae from the mile-long beach by the end of July; several years ago, villagers cleaned up 21,000 tons.

"This bay is magnificent and, unfortunately, this tarnishes the image," said Ropartz, adding that the horse's death shows the role of the algae "is no longer in doubt" and spurred the government into action.

Prime Minister François Fillon visited Saint-Michel-en-Grève last week, pledging to control the algae by next spring.

The horse is only the latest victim of the algae's noxious fumes. A man was found dead on the same beach two decades ago, his arm sticking out from a pile of algae. Another man fell into a four-day coma after cleaning algae 10 years later. Last year, two dogs died while romping on an algae-covered beach 60 miles east.

Solving the problem will take far more than cleaning algae from beaches.

Water in the affected region measures 32-33 milligrams per liter of nitrate — compared to a normal level of 5 milligrams, said Alain Menesguen, a biologist with the French Institute for Exploitation of the Sea. Some rivers reach 60-70 milligrams, and the groundwater in some areas reaches 100 milligrams, he said.

"We've reached saturation," he said. Returning to normal levels will require huge changes in agriculture, and the results won't be visible immediately.

"This is very difficult for farmers and politicians to accept," Menesguen said.

Solange Le Guen, who raises 80 cows on a farm planted with corn, wheat and other crops in the hills behind Saint-Michel-en-Grève, said farmers aren't the only ones to blame.

Fault also lies with water-purification plants too close to the ocean, she said. She conceded, when pressed, that "people have abused" fertilizers. "We were badly advised," she said.