Ancient Mayan cities were dangerously contaminated with mercury, study finds

A scientific team discovered mercury buried deep in the soil and sediments.


The ancient cities of the Mayan civilization ,  which could be a health hazard to its population.

The subsoil of the ancient cities of the Mayan culture had high levels of mercury contamination , which was due to the frequent use of this element and products that contain it during the classic period, which could be a danger to their health.

An article published by Frontiers in Environmental Science adds that this contamination is, in some places, so strong that even today it could be a potential danger.

Discover mercury buried deep in the soils and sediments of ancient Mayan cities”It’s hard to explain until we start looking at the archeology of the region, which tells us that the Maya used mercury for centuries,” explained lead author Duncan Cook of Australian Catholic University.

The team reviewed for their study all the data on mercury concentrations in the soil and sediments of the archaeological sites of the ancient Mayan world In the Classic Period sites (

from 250 to 1100), for the sites where there are measurements, mercury contamination was detectable in Chunchumil (Mexico); Marco Gonzales and Actuncan (Belize); La Corona, Tikal, Petén Itzá, Piedras Negras and Cancuén (Guatemala); Palmarejo (Honduras) and Cerén (El Salvador).

Chan b’i (Belize) is the only place with available data where no mercury contamination was detected.

Concentrations range from 0.016 parts per million in Actuncan to “the extraordinary figure” of 17.16 parts per million in Tikal. The toxic effect threshold (TET) for mercury in sediment is defined as 1 parts per million.

Mercury vessels and paintings

To search for the origin of this contamination, the authors point out that sealed vessels filled with liquid mercury have been found in Mayan sites such as Quiriqua (Guatemala), El Paraíso (Honduras) and the ancient multi-ethnic megalopolis of Teotihuacan (central Mexico).

Elsewhere in the Maya region, archaeologists found objects painted with mercury -containing paints , primarily made with the mineral cinnabar or vermilion.

Therefore, they conclude that the ancient Maya frequently used paints and powders containing cinnabar for decoration, a mercury that could have leaked from the patios, floor areas, walls and ceramics, and later spread to the ground and air. Water.

“For the Mayans , objects could contain ch’ulel, or ‘soul force,’ which resided in the blood. Thus, the bright red pigment of cinnabar was a priceless and sacred substance,” explained other authors Nicholas Dunning , from the University of Cincinnati (USA).

But, without knowing it, “it was also deadly and its legacy persists in the soils and sediments of ancient Mayan sites ,” he added.

Since mercury is scarce in the limestone that underlies much of the Maya region , experts believe that the elemental mercury and cinnabar found in the Maya deposits may have originally been mined from known sites on the northern and southern limits of the Maya. old worldMaya , and imported to the cities by the merchants.

chronic poisoning

All this mercury would have been a danger to the health of the ancient Mayans , the study points out, since the effects of chronic poisoning by this element include damage to the central nervous system, kidneys and liver, tremors, vision and hearing problems, paralysis and mental health problems.

The team believes that more research is needed to determine whether mercury exposure played a role in broader sociocultural changes and trends in the Maya world , such as those that occurred toward the end of the Classic period. 

(With information from EFE)