In ancient Mayan cities, Mesoamerica found a huge amount of mercury in soil, and in an overview in the journal Frontiers in Environmental Science, researchers concluded that the pollution was caused by the frequent use of mercury and mercury-containing products, and in places it was so severe that it was a potential health hazard for archeologists.
" Mercury pollution usually occurs in modern urban areas and industrial landscapes," noted Dr. Duncan Cook, Associate Professor of Geography at the University of Australia. "Detecting mercury buried deep in soil and sediment in ancient Mayan cities is difficult to explain until we begin to look at the archaeology of the region, which tells us that Maya has used mercury for centuries."
Cook and his colleagues analysed all the data on mercury concentrations in soil and sediment at archaeological sites throughout the ancient Mayan area and showed that mercury levels were very high at classical sites.
The authors emphasize that leakproof receptacles filled with liquid mercury were found at several Maya sites, such as Quirique in Guatemala, El Paraíso in Honduras and the former multi-ethnic megapolis of Theotiucán in Mexico; in other locations in the Maya region, archaeologists found articles painted with mercury-containing paints, mainly made from the mineral of the movie.
The authors conclude that ancient Maya often used mercury-containing paints and powders for decorations, which could be leached from indoor yards, floors, walls and ceramics and then into soil and water.
Since mercury is rarely found in the limestone that underlies most of the Mayan region, they suggest that elemental mercury and the film made at the Maya sites could be extracted from known deposits on the northern and southern borders of the ancient Maya world and imported into cities by traders.
Mercury was a health hazard to ancient Mayans: for example, the effects of chronic poisoning include damage to the central nervous system, kidneys and liver, tremor, impaired vision and hearing, paralysis, and mental disorders.