A group of international scientists were able to discover that ancient pollution did exist and it was caused by Neanderthal fires. The traces of the said environmental letdown that existed some 450,000 years ago in prehistoric caves were explored by researchers from the Gibraltar Museum and the University of Gibraltar.
Over time, humans have devised diverse and evolving ways to thrive. Industrial activities such as mining, smelting and creation of synthetic compounds have widely spread, imposing directly proportional increase in the emission of heavy metals to the environment. With this, major hazards to human health and well-being have also rose.
In the new study, the authors aimed to assess the presence of heavy metals in different archaeological locations, known to have served as settlements for Homo species. To achieve this goal, the researchers studied the geochemical properties of four sites in the Iberian Peninsula namely the Gorham's Cave, Vanguard Cave, El Pirulejo Cave and Gran Dolina. They also conducted experimental fires to identify the associations between the wood ashes and the tremendous concentrations of heavy metals in the cave debris.
The findings of the study, published in the journal Scientific Reports, showed that in Gorham's Cave, Neanderthals were already causing pollution in the environment as they build fires. According to the study, copper and zinc concentrations were found to be high and may be comparable to the pollution that the present-day world is experiencing.
In Vanguard Cave, massive metal pollution was noted as well, also due to the Homo's creation of fires.
The utilization of galena, which is a lead sulphide used to create beads was the main culprit for the same type of pollution discovered in the El Pirulejo Cave, located in the southern part of Spain.
Lastly, in Gran Dolina, traces of heavy metal pollution were also observed; however, the said damages were incurred from droppings of bats and birds, and not because of human activities.
"It is the earliest known evidence of heavy metal pollution resulting from human activity," Clive Finlayson, the director of Gibraltar Museum, told in an interview.
The data collated in the study were said to imply that Neanderthals settled in caves with high concentrations of heavy metals at least from the Middle Paleolithic period. With this, the effect of prolonged exposure to heavy metals may have been insignificant, but this still depends on the manner with which the people interacted with the precipitates.
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