Mercury Contamination Rampant in Ancient Maya Cities, Sealed Elemental Liquid Jars Found

Mercury contamination is still a problem in the majority of historic Maya cities today. On archaeological digs, sealed jars containing elemental liquid have been discovered.

In a research article, researchers concluded that the Maya of the Classic Period, which lasted from 250 to 1100 CE, were the ones who frequently used mercury and products containing mercury.

There are areas where the pollution is so bad that it could still present a health risk to unwary archaeologists today.

Using Mercury for Centuries

According to Dr. Duncan Cook, an associate geography professor from the Australian Catholic University, modern urban areas and industrial landscapes are typically where mercury pollution in the environment can be found.

Until the team started to take into account the archeology of the area, which claimed that the Maya were using mercury for centuries, the discovery of mercury buried deep in sediments and soils in ancient Maya cities would be difficult to explain.

Cook, the lead author of the study, and his colleagues here conducted a comprehensive review of all available information on mercury concentrations in soil and sediments at ancient Maya sites.

They demonstrated that mercury pollution is detectable everywhere at Classical Period sites for which measurements are available, except Chan b'i.

Actuncan has a concentration of 0.016 ppm, while Tikal has an astounding 17.16 ppm.

For comparison, the Toxic Effect Threshold (TET) is set at 1 ppm for mercury in sediments.

Adorned with Mercury and Cinnabar

The authors draw attention to the discovery of sealed vessels containing "elemental" mercury, or liquid mercury, at numerous Maya sites, including Quiriqua in Guatemala, El Paraiso in Honduras, and the formerly multiethnic megacity Teotihuacan in Central Mexico.

Archaeologists have discovered objects painted and adorned with mercury-containing paints, mostly made from the mineral cinnabar, in other parts of the Maya region.

The authors concluded that cinnabar, as well as mercury-containing powders and paints, were widely used by the ancient Maya for decoration.

Dr. Nicholas Dunning, a professor from the University of Cincinnati, explained that for the Maya, objects could encompass ch'ulel, or soul-force, which resided in blood.

As a result, this mercury may have leached from patios, floors, walls, and ceramics.

Consequently, the brilliant red cinnabar pigment was a priceless and sacred material, but unbeknownst to them, it was also lethal, and its effects can still be seen in the soil and sediments surrounding historic Maya sites.

Dunning is a co-author of the study.

They hypothesized that the cinnabar and elemental mercury discovered at Maya sites may have been previously mined from known deposits on the southern and northern confines of the ancient Maya community and imported to the cities by traders because mercury is scarce in the limestone which underlies much of the Maya region.

Reas also: Imaging Technology Reveals Hidden Ancient Maya City with Buildings 

Mercury Poisoning, Mayacene

For example, chronic mercury poisoning damages the liver, kidneys, and central nervous system and results in tremors, blurred vision, paralysis, hearing loss, and mental health issues.

The ancient Maya would have been at risk from all of this mercury.

The fact that one of the last Maya kings of Tikal, Dark Sun, who reigned around 810 CE, is portrayed in murals as pathologically obese is perhaps significant.

Metabolic syndrome, which can be brought on by chronic mercury poisoning, is known to have obesity as a side effect.

If mercury exposure contributed to more significant sociocultural trends and changes in the Maya world, similar to those at the end of the Classic Period, more investigation is required.

Dr. Tim Beach, a professor from the University of Texas at Austin, said that even the prehistoric Maya, who hardly ever used metals, greatly increased the levels of mercury in their surroundings.

This finding provided additional proof that there was a Maya Anthropocene, also known as the "Mayacene," which parallels how humans live today in the "Anthropocene."

Metal contamination appears to be a historical consequence of human activity.

Beach is also a co-author of the study, Phys Org reported.

Related article: Collapse of the Ancient Maya Blamed on Drought and Shifts in Climate