Sargazo Influx in Quintana Roo Poses Health and Environmental Risks, Experts Warn

Quintana Roo, Mexico — As a new influx of sargazo seaweed approaches the coast of Quintana Roo in 2026, experts warn the issue extends beyond environmental damage to pose direct risks to human health, while authorities have yet to establish a final disposal plan for the collected algae.

Rosa Elisa Rodríguez Martínez, a researcher at the National Autonomous University of Mexico (UNAM) in Puerto Morelos, cautioned that the high concentration of the macroalgae leads to beach erosion and pollution in the Mexican Caribbean. During decomposition, sargazo releases toxic compounds like hydrogen sulfide, which can contaminate air and water, affecting mangroves, seagrasses, and wildlife including sea turtles.

State and municipal authorities have not determined the final destination for thousands of tons of collected sargazo, nor detailed whether containment cells or adequate infrastructure exist for its management on Caribbean beaches.

Research documents two main sargazo species: Sargassum natans, with long stems and narrow leaves, and Sargassum fluitans, with shorter stems and broad leaves. Both rely on air-filled vesicles to stay afloat and are considered responsible for mass accumulation events in the Caribbean, Gulf of Mexico, and Atlantic Ocean.

In Playa del Carmen, municipal authorities say they established a collection center authorized by the State Secretariat of Environment (SEMA) in 2025, located along the federal highway. At this site, sargazo removed from beaches is concentrated, sand is separated, and it is dried for various uses, after four clandestine dumps were detected.

In Cancún, Antonio de la Torre Chambé, director of Municipal Public Services, said workers collect the macroalgae from 12 public beaches. “We collect it and hand it over to Zofemat (the Federal Maritime Terrestrial Zone),” he stated.

Municipal authorities claimed during the 2025 sargazo season that space would be enabled in the emergency cell of parcel 175 to deposit collected material, but necessary protection measures to prevent seepage into the subsoil have not been specified to date.