On Mexico’s Caribbean coast, mountains of sargassum seaweed raise a growing stink

Workers hired by residents have been removing sargassum seaweed from the Bay of Soliman, north of Tulum in Mexico’s Quintana Roo state. (Eduardo Verdugo / AP)

TULUM, Mexico — Scraping the smelly sargassum seaweed off some beaches on Mexico’s resort-studded Caribbean coast has become not only a nightmare but also possibly a health threat for the workers doing it — with mountains of the stuff washing ashore this year.

Sargassum is a kind of algae. When it decomposes, it generates hydrogen sulfide gas. In small amounts in open areas, it’s not much more than an annoying odor: sulfurous, like rotting eggs.