An international and interdisciplinary team of researchers has described the toxic pollution found during various expeditions to Mayan cities. Scientists have concluded that these settlements were dangerously polluted with mercury, and these pollution are not modern.
The study is presented in the journal Frontiers in Environmental Science, and briefly about it tells Phys.org. The authors of the review article concluded that the toxic pollution found in ancient Mayan cities throughout Mesoamerica is not modern.
A new study proves that these dangerous outbreaks are associated with the frequent use of mercury and mercury-containing products in the so-called classic period of the Mayan civilization (between 250 and 1100 AD). Moreover, in some places the concentration of toxic substances is so high that it poses a real threat to the health and life of archaeologists studying the ruins.
“Environmental mercury pollution is commonly seen in modern urban areas and industrial landscapes. Its presence in the ancient Mayan cities was difficult to explain until we began to look at the archeology of the region. It tells us that the Maya used mercury for centuries,” says the presenter. study author Dr. Duncan Cook.
The team reviewed all available data on mercury concentrations in soil and sediments that have been found at archaeological sites in ancient Mayan cities. Only the city of Chanbi in Belize turned out to be “environmentally friendly”. At the same time, high concentrations of mercury have been found in Mayan cities such as Chunchumil in Mexico, Marco Gonzalez and Aktuncan in Belize, La Corona, Tikal, Peten Itza, Piedras Negras and Cancuen in Guatemala, Palmarejo in Honduras and Seren in El Salvador.
As the researchers write, mercury concentrations range from 0.016 ppm at Aktunkan to an incredible 17.16 ppm at Tikal. For comparison, the toxicity threshold for mercury in sediment is defined as one part per million. The question of how exactly the pollution occurred is not a mystery to scientists.
The fact is that the Maya widely used cinnabar – a natural red pigment saturated with mercury. Archaeologists often and in large quantities find objects painted with mercury-containing paints. Recent research has also shown that cinnabar was widely used in building decorations.
“The Maya believed that various objects could contain ‘chulel’, or soul power, which was in the blood,” explains study co-author Dr. Nicholas Dunning. “Thus, the bright red pigment of cinnabar was a priceless and sacred substance. But it is also was deadly, and this legacy is still preserved in the soil and bottom sediments around the ancient Mayan settlements.”
Scientists also found that there were no natural sources of mercury and cinnabar near Mayan cities. This means that the Maya imported cinnabar. Probably, this pigment was brought by merchants from afar. There is even a theory that mercury contributed to the collapse of the Mayan civilization. It has accumulated in settlements for centuries, causing chronic poisoning among local residents. Scientists have paid attention, for example, to the fresco of one of the last rulers of Tikal – the leader of the Dark Sun, who ruled around 810 AD. In the frescoes, he is depicted as morbidly obese, and obesity is a known consequence of the metabolic syndrome that can be caused by chronic mercury poisoning.