Open the world's oldest environmental pollution

In the caves of Spain and Gibraltar, scientists have discovered traces of the oldest in the world history of environmental pollution caused by human activity.
As reported Agency France-Presse, the caves were found the next exit to the surface of heavy metals - copper, lead, nickel and zinc, dating back to the beginning of the Stone Age. The cause of emissions become bonfires fueled in caves by prehistoric people who lived there, soot and ashes from them.

The most significant contamination was found in a cave in a small area Gorham British territory in the south of Spain, where well-preserved settlements of the Neanderthals. "This is the earliest known scientific evidence of environmental pollution that occurred as a result of human activity," - said in a report published in the journal Scientific Reports.

Also traces of contamination by heavy metals were found in the cave of Gibraltar Vanguard («Vanguard") and the cave of El Piruleyo in southern Spain, where they found significant traces of galena (lead sulfide). It was used as a dye Neanderthals in making beads. Another contamination found in the cave of Atapuerca Mountains near the city of Burgos in central Spain, which is now underway scale paleontological work. However, there are scientists rejected the human factor. In their conclusion, the output of metal occurred as a result of abundant deposits of droppings of birds and bats.

Scientists believe they have discovered contamination are not dangerous for the modern man and is unlikely to have a major impact on the population of our ancestors. The most valuable discoveries, according to the researchers, is that now need to re-evaluate the environmental impact of fires and the effects of fires, which has previously been neglected.

Earlier, experts have said that the problem of environmental pollution with heavy metals is now becoming urgent. As an example, they cited decline in the population of wild bees in Europe, which was caused by heavy metals from smelters in Poland and the UK. In areas that are not contaminated with metals, lived to 10 species of bees, while contaminated sites can be difficult to find at least one.