Mercury from ritual pigments linked to Maya civilization sites

Researchers identified high concentrations of mercury in lake sediments near two ancient Maya archaeological sites in the Yucatán Peninsula, Mexico.

The team analyzed samples from Coba, a well-studied site, and Xcach, a lesser-known location. They found some of the highest mercury levels ever recorded in locations from the Maya era. The contamination occurred due to the Maya use of cinnabar, a red mineral used in religious and cultural rituals.

The Maya used this mineral as a pigment for murals and temples, and in funeral rites. Because cinnabar contains mercury, its use caused toxic substances to seep into the soil and water. Matt Waters, a professor at Auburn University and the study's lead author, stated that the mercury levels found far exceeded modern toxicology and pollution limits. The mercury affected the local ecosystem, causing a decline or disappearance of bacteria, algae, cyanobacteria, shelled organisms, and mosquitoes in the lake sediments.

Savanna Wooten, a postdoctoral researcher at the Jones Center, suggested that the Maya people might have been exposed to the metal by drinking water or eating fish. While the researchers did not find direct evidence of human exposure in the sediment records, the study adds environmental stress to the list of factors, such as climate change and war, that contributed to the decline of Maya cities.