Researchers have discovered toxic quantities of mercury frequently associated with the waste products of modern industry in ancient Maya settlements.

Long before conquistadors set foot on their lands, Maya tribes may have been treating the soil of ancient urban centers with mercury, as revealed by ScienceAlert. Researchers were urged to protect their health because the sites had high mercury levels.

Researchers Find Mercury in Ancient Maya

The multidisciplinary team of experts examined all the information on mercury pollution at ten distinct Mayan archaeological sites.

At least one site at seven out of the 10 had mercury pollution. Most of these sites date from the Late Classic era, which happened at the end of the first millennium CE. By the 10th century, every site had been abandoned.

At Actuncan, mercury concentrations range from 0.016 parts per million (ppm) to 17.16 ppm.

"The levels of total mercury found in some ancient contexts at Maya sites today are equal to or greater than modern guidelines we have in place for safe exposure limits for mercury in soils, such as the WHO's recommended safe limit for mercury in soils for agriculture, which is 0.05 ppm," study lead author Dr. Duncan Cook, an associate professor of geography at the Australian Catholic University said in a Cosmos report.

However, he continues that it's "extremely impossible to define" how deadly a specific Maya site is.

MEXICO-ASTRONOMY-SPRING-EQUINOX
(Photo: HUGO BORGES/AFP via Getty Images)
View the stairs of the castle of Kukulcan at the Mayan archaeological site of Chichen Itza in Yucatan State, Mexico, during the spring equinox celebration on March 21, 2022.

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About Red Cinnabar

The mineral crystal mercury sulfide, usually referred to as cinnabar, is another that has been used historically as a mercury source.

According to geoarchaeologist Nicholas Dunning of the University of Cincinnati, the Maya thought some objects might contain the ch'ulel, or soul-force, found in the blood.

Consequently, the red cinnabar pigment was a rare and precious material, but it was also poisonous, and according to Dunning, its effects may still be detected in the soil and sediments close to ancient Maya settlements.

The ancient Maya infrastructure was built on limestone. However, this limestone lacks the geology necessary for cinnabar production.

According to an archeological study, cinnabar was mined in Central America during the second and first millennia BCE, during the height of the Olmec civilization.

The Maya people started constructing monuments to their gods around the third century CE. Cinnabar was used extensively, primarily as a powder to color decorations or even in funeral rites.

According to ScienceAlert, Dark Sun, the final ruler of the Maya metropolis of Tikal, was notably overweight, which may have been a symptom of a metabolic disease brought on by mercury poisoning.

The research authors emphasize the need for present archaeologists to use caution as they sift through the complex history of Maya society.

Researchers published their study in Frontiers in Environmental Science.

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