• New sensors have been installed around the bays invaded by green algae.

  • The aim is to monitor concentrations of hydrogen sulfide, a toxic gas that escapes from rotting algae.

  • The authorities have deployed additional financial resources to support farmers in the sectors concerned.

It is a very poisonous gas which has already killed horses, dogs and wild boars.

If justice has never been able to prove it, the hydrogen sulphide which escapes from green algae has undoubtedly already killed men in Brittany.

Dangerous for both humans and animals, H2S will be monitored more closely by the authorities.

This Thursday, the Regional Health Agency and the regional prefecture announced that eight hydrogen sulphide sensors had been installed near green algae stranding areas in Côtes-d'Armor and Finistère.

Four sensors had already been installed in the past two years in the region.

This network of sensors will make it possible to detect situations of abnormal gas emissions and to alert the authorities “and to adapt the measures for managing the area and protecting the population” specifies the ARS.

The data collected will also be available from July on the website of the Air Breizh association responsible for monitoring air quality in the region.

The authorities insist on “the duty of transparency” vis-à-vis the population.

The excess threshold is set at 1 ppm (part per million), as recommended by the High Council for Public Health.

At this threshold, the human body generally detects a "rotten egg" odor.

It is estimated that pulmonary edema can occur at a concentration of 300 ppm and rapid loss of consciousness can be caused by a concentration of more than 500 ppm.

A rotten summer on the beaches of Brittany?

While the strandings were very early this year, in particular due to the low dispersion of algae last winter.

The authorities are expecting a complicated summer on the beaches of Brittany because the quantities of ulva are significant near the coast.

Other measures were also announced this Thursday on the sidelines of the Carrefour de l'eau organized in Rennes.

The plan to combat the proliferation of green algae 2022-2027 provides for a strengthening of State resources on the regulatory side.

Certain restrictive measures could be imposed on farmers operating in the watersheds of the eight bays concerned.

Many environmental associations had asked for an extension of the measures to all of Brittany, as more and more sites "outside territorial contracts" were affected by proliferation.

New financial aid should be released and allow "support for 190 new farmers", according to the prefecture.

Planet

Green algae: Sensors soon to be installed in eight Breton bays to measure air quality

Planet

The world is facing "a state of emergency of the oceans", warns the head of the UN

  • Planet

  • reindeer

  • Saint Brieuc

  • Brest

  • green algae

  • Pollution

  • Gas

  • Air pollution

  • Sea

  • Brittany