Mounds of rotting seaweed clogging beaches across northwestern France are emitting a toxic and potentially lethal gas, test results released by the government showed on Thursday.
Tests were ordered on the foul-smelling algae, which green groups blame on nitrates fertilisers used by local farmers, after a horse apparently died from inhaling fumes on a beach in Saint Michel de Greve in Brittany.
Results showed the seaweed in Saint Michel was giving off dangerous levels of hydrogen sulphide (H2S), sometimes referred to as "sewer gas" because it is produced by the breakdown of putrified waste material...
Several points on the beach tested positive for hydrogen sulphide at a concentration of 1,000 parts per million, a level that "can be deadly in a few minutes," the report said...
The build-up of rotting weed on shores in more than 80 towns around Brittany has worried residents and threatened the region's lucrative tourist industry, with part of the coastline already declared off-limits.
Green groups blame nitrate pollution caused by intensive agriculture -- especially among pig farmers -- and have accused the government of turning a blind eye to an "environmental cancer."