According to a new study, humankind is now entering the "Age of Plastic". The research investigates the evidence that we are living in the Anthropocene, a time in which humanity is the main geological force. Jan Zalasiewicz, Professor of Palaeobiology at the University of Leicester, explained: "Plastics were more or less unknown to our grandparents, when they were children. But now, they are indispensible to our lives".
"They're everywhere -- wrapping our food, being containers for our water and milk, providing cartons for eggs and yoghourt and chocolate, keeping our medicines sterile. They now make up most of the clothes that we wear, too. Plastics are also pretty well everywhere on Earth, from mountain tops to the deep ocean floor and can be fossilized into the far future" Zalasiewicz continued. "We now make almost a billion tons of the stuff every three years. If all the plastic made in the last few decades was clingfilm, there would be enough to put a layer around the whole Earth. With current trends of production, there will be the equivalent of several more such layers by mid-century".
Since plastic is inert and so hard to degrade it will have a very long-lasting impact on the Earth's geology. Throwing plastic on the ground means that it will become part of the soil and will eventually end in the sea, contaminating it and causing the death of fish, plankton and seabirds. Once in the ocean, plastic can travel fast and for many miles thanks to great oceanic garbage patches or it coud just lay on the bottom of the sea, becoming part of the strata of the future.
Professor Zalasiewicz added: "Plastics will continue to be input into the sedimentary cycle over coming millennia as temporary stores -- landfill sites -- are eroded. Once buried, being so hard-wearing, plastics have a good chance to be fossilized -- and leave a signal of the ultimate convenience material for many million years into the future. The age of plastic may really last for ages".
The study was carried out by an international team of scientists including the University of Leicester's Professors Jan Zalasiewicz and Mark Williams and PhD student Yasmin Yonan from the Department of Geology and field archaeologist Dr Matt Edgeworth who is an Honorary Visiting Research Fellow from the School of Archaeology and Ancient History. Dr Edgeworth said: "It may seem odd to think of plastics as archaeological and geological materials because they are so new, but we increasingly find them as inclusions in recent strata. Plastics make excellent stratigraphic markers".
Colin Waters from the British Geological Survey, a co-author of the study, added: "We have become accustomed to living amongst plastic refuse, but it is the 'unseen' contribution of plastic microbeads from cosmetics and toothpaste or the artificial fibres washed from our clothes that are increasingly accumulating on sea and lake beds and perhaps have the greatest potential for leaving a lasting legacy in the geological record".