Antilles sargassum and Saharan dust haze jeopardize schools and health

Massive strands of sargassum washing ashore in the Antilles are decomposing and releasing hydrogen sulfide and ammonia, gases that irritate eyes, cause headaches, nausea and respiratory distress. In several schools the resulting indoor air pollution has led to reduced classes, temporary closures, and the need for enhanced ventilation.

At the same time, Saharan dust plumes carrying fine PM10 particles have created hazardous haze over Guadeloupe and nearby islands. The dust not only irritates the respiratory system but also supplies nutrients such as iron and phosphorus that accelerate sargassum growth, producing a double pollution threat. Local air‑quality agency Gwad'Air issued red alerts in early June 2026, later downgraded to yellow, while health authorities (ANSES) warned of the combined health risks for children, the elderly and asthmatics.

The phenomenon is linked to warming ocean temperatures and changing wind patterns, which together increase the frequency and intensity of both dust events and sargassum invasions, straining public‑health resources and school operations in the French Antilles.