The presence of unwanted substances in the environment is termed as pollution. Humans are responsible for the increase in the pollution levels over the years. A Tel Aviv University research in collaboration with scholars from Spain, the U.K. and Australia suggests that man could have started polluting around 400,000 years ago.
Researchers have uncovered evidence of food and potential respiratory irritants entrapped in the dental calculus of 400,000-year-old teeth at Qesem Cave near Tel Aviv, the site of many major discoveries from the late Lower Paleolithic period. The study led by Prof. Karen Hardy of ICREA at the Universitat Autonoma, Barcelona, Spain, provides direct evidence of what early Palaeolithic people ate and the quality of the air they breathed inside Qesem Cave.
The researchers suggest that possible respiratory irritants, including traces of charcoal-manmade environmental pollution-found in the dental calculus, may have resulted from smoke inhalation from indoor fires used for roasting meat on a daily basis. This earliest direct evidence for inhaled environmental pollution may well have had a deleterious effect on the health of these early human beings.
Prof. Gopher said, "Because the cave was sealed for 200,000 years, everything, including the teeth and its calculus, were preserved exceedingly well. The analyzed calculus revealed three major findings- charcoal from indoor fires; evidence for the ingestion of essential plant-based dietary components; and fibers that might have been used to clean teeth or were remnants of raw materials. This was the first evidence that the world's first indoor BBQs had health-related consequences. The people who lived in Qesem not only enjoyed the benefits of fire-roasting their meat indoors-but they also had to find a way of controlling the fire-of living with it."
The research is published in Quaternary International.