Seaweed strandings cause a stink – here’s why they harm your health

Seaweed piling up on a beach might look harmless, but as it begins to rot, it can release gases that are toxic to people.

Workers remove massive accumulations of _Sargassum_ seaweed from a Caribbean beach in the Riviera Maya near Cancun, Mexico, in June 2025. elena.tres/Shutterstock Seaweed piling up on a beach might look harmless, but as quantities begin to rot, they can release gases that are…