For more than 1,000 years, the ancient Mayan city of Tikal embodied one of the largest and most important urban centers ever built by this mysterious and enduring pre-Columbian civilization. However, by the end of the 9th century AD e. this maya metropolis has broken up. Around the same time, Tikal and a number of other cities were abandoned. A new study by scientists published in the journal Scientific Reports sheds light on the disappearance of an ancient civilization.
A team of researchers from the University of Cincinnati analyzed reservoir deposits in an ancient city located in modern Guatemala. Scientists have found evidence of toxic pollutants in Tikal’s drinking water that would make it unsuitable for drinking.
For a vast city, prone to severe droughts and cut off from lakes and rivers, contaminated rainwater collectors could lead to disaster. According to scientists, up to 100,000 people lived in the city.
The transformation of the central reservoirs of Tikal from places of livelihood to the epicenter of infection and disease could lead to the devastation of this ancient city, scientists are sure.
To understand how Tikal’s reservoir systems supported (and then couldn’t) support the city’s population, a research team led by biologist David Lenz took sediment samples from 10 city reservoirs.
Analysis of DNA still contained in ancient mud revealed traces of two different types of cyanobacteria (blue-green algae) in the tanks.
Evidence suggests that these organisms are Planktothrix and Microcystis, which have existed in reservoirs for many centuries during the heyday of Tikal. However, these blue-green algae bloom during a drought, which happened before the end of Tikal in the middle of the 9th century A.D. e.
Water would look dirty. It would have been disgusting to taste. No one would like to drink this water.
Kenneth Tankersley, archaeologist-geologist from the research team
Water saturated with bacteria was not the only source of toxicity. The analysis also revealed high levels of mercury in the sediment.
After excluding potential sources of mercury pollution from the natural environment (leaching of mercury into water bodies from the underlying rock or falling on them due to volcanic ash), the researchers realized that it was Maya that probably polluted the water.
Color was important in the ancient Mayan world; they used it in their frescoes. When painting gypsum in red, which they later used in burials, the Mayans combined it with iron oxide to obtain different shades.
Unfortunately, one of the ingredients that they used in their paints was mineral cinnabar of red color. It is a form of mercury sulfide and is toxic to people who come in contact with it.
This toxicity may have been known by Maya, as it was known to other ancient peoples. But no matter how safe they handle toxic waste, they probably would never have realized that over time rainwater flushes dangerous levels of toxic pigment from painted surfaces into the city’s ponds.
As a result, residents of Tikal were likely to receive mercury-contaminated food at each meal. Polluted waters would have a negative impact on the health of society, especially the ruling elite, and could jeopardize their ability to manage effectively.
At the same time, arid climate and environmental degradation were also huge problems for Maya, but the lack of fresh drinking water is an important symbol in the culture, perhaps the last straw in a drought-damaged, polluted city on the verge of collapse.