Yucatán Peninsula cenotes face high heavy metal contamination

Researchers from the National Autonomous University of Mexico (UNAM) have identified high levels of contamination in the cenote networks of the Yucatán Peninsula. The study revealed concentrations of heavy metals and pollutants—including lead, aluminum, chromium, and ammonium—at levels up to five times higher than permitted environmental limits.

In Tulum, the contamination is linked to rapid urban growth and a lack of basic sanitation infrastructure. Currently, only 45% of Tulum's urban area is connected to a sanitary drainage network. The use of improvised septic tanks in coastal areas and irregular settlements allows untreated wastewater to filter directly into the underground karst system.

Separately, authorities in Tulum are conducting soil mechanics studies at the Sac-Bé kindergarten in the Los Huracanes subdivision. Following requests from parents, Civil Protection and engineers are investigating the potential presence of a cenote, cavern, or sinkhole beneath the school grounds to ensure student safety and determine the viability of future campus expansions.