Researchers at Cincinnati University, Ohio, USA discovered the level of poisoning in 2 reservoirs in the center of Tikal city - an ancient Maya city dating back to the 3rd century BC and currently located in the northern area of Guatemala, Phys.org informed.
Researchers' findings suggest that the possibility of droughts around the 9th century contributed to the decline and eventually abandonment of the abandoned city of Tikal.
"The conversion of Tikal's central reservoirs from places of life support to places of disease has both practical and symbolic significance, leading to the abandonment of this magnificent city" - the study concluded.
A geochemical analysis shows that the two reservoirs near the city's palaces and temples have mercury toxicity, which researchers at the University of Cincinnati have shown originating from the dye used by ancient Maya people to decorate buildings, paint clay items and other items.
During the rainy and stormy season, mercury from the dye seep into reservoirs and settle in sedimentary layers over time.
However, Maya people living in the ancient city once had abundant drinking water from nearby non-poisoned reservoirs, according to researchers at the University of Cincinnati.
Details of this study were published in the journal Nature Journal Scientific Reports.
The University of Cincinnati's diverse research team, including anthologists, geologists, botanists, biologists and chemists, has examined sedimentary layers since the 9th century when Tikal was still a thriving city.
Previously, researchers discovered that the soil around Tikal in the 9th century was extremely fertile and originated from frequent volcanic explosions that made fertile land in the Yucatan peninsula.
archaeologists and anthologists have been trying to find out what has happened to the Maya civilization for more than 100 years, says David Lentz, a professor of biology at the University of Cincinnati, lead author of the study.
In the latest study, researchers took samples from 10 reservoirs in the city and analyzed ancient DNA found in the clay layer of 4 reservoirs.
Remains from reservoirs near the central Tikal temple and palace show traces of leprosy bacteria. Using water contaminated with Lam bacteria, especially during droughts, can make people sick, even if the water has boiled, says David lentz.
"We have found two types of blue algae that produce toxic substances. The bad thing about them here is that they have the ability to prevent boiling, making the water in these reservoirs too toxic to drink," he said.
However, researchers say that Maya people may not use water in these reservoirs for drinking, cooking or watering.
Today, Tikal is a national park and a world heritage by UNESCO. Researchers believe that the combination of economic, political and social factors has prompted people to leave the city and neighboring farms. However, Mr. Lentz said that climate, with a prolonged dry season making it difficult for people to find water, is certainly a factor contributing to this move.
