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While extracting samples from a Pakistani landfill site outside of Islamabad, researchers discovered a soil fungus that feeds on plastic.
It is no surprise that landfills around the world contain tons upon tons of plastic. When combined with the oceans’ contents, the number reaches into the billions of tons — and humans continue to produce plastic in factories daily, despite efforts at recycling and creating reusable substances.
<p><span style="font-weight: 400;">For this reason, the human race has </span><a href="http://www.iflscience.com/environment/strong-evidence-earth-has-entered-anthropocene/"><span style="font-weight: 400;">introduced what is called the Anthropocene</span></a><span style="font-weight: 400;">, a new geological epoch caused by ample changes to the planet, warranting the classification from the former </span><a href="https://en.wikipedia.org/wiki/Holocene"><span style="font-weight: 400;">Holocene</span></a><span style="font-weight: 400;">. The sheer number of plastics produced, as well as the abundance of concrete structures around the world, carbon pumped into the atmosphere with regularity and phosphorous and nitrogen permeating the Earth’s soil represent this new change — though they are also a large part of its cause, </span><a href="http://science.sciencemag.org/content/351/6269/aad2622"><span style="font-weight: 400;">as scientists believe</span></a><span style="font-weight: 400;">.</span></p><p><span style="font-weight: 400;">But back to landfills: one remarkable, but not wholly unexpected, effect of the Anthropocene is a species of fungus called </span><a href="https://en.wikipedia.org/wiki/Aspergillus_tubingensis"><span style="font-weight: 400;">Aspergillus tubingensis</span></a><span style="font-weight: 400;">, which degrades plastic by feeding on it. In lab experiments, Aspergillus tubingensis </span><a href="https://www.britannica.com/science/mycelium"><span style="font-weight: 400;">mycelia</span></a><span style="font-weight: 400;">, or the branched, tubular filaments of the fungus, seize the polyester polyurethane plastic, engendering a breakdown and scarring of the plastic’s surface. These results were published in </span><a href="http://www.sciencedirect.com/science/article/pii/S0269749117300295?via%3Dihub"><i><span style="font-weight: 400;">Environmental Pollution</span></i><span style="font-weight: 400;">, volume 225</span></a><span style="font-weight: 400;"> in June 2017.</span></p><p><div data-conversation-spotlight=""></div></p><p><span style="font-weight: 400;">Organisms have fed on plastic waste in prior instances, so this particular finding in the Pakistani landfill site is not the first.</span></p><p><span style="font-weight: 400;">Plastic-degrading bacteria uncovered both most recently and in the past accompany </span><a href="http://www.iflscience.com/plants-and-animals/a-caterpillar-so-hungry-it-will-even-eat-plastic/"><span style="font-weight: 400;">another, larger discovery from earlier this year</span></a><span style="font-weight: 400;">: the wax worm, which can naturally deteriorate plastic because of its similarity to beeswax, the worm’s typical and natural food source.</span></p><p><span style="font-weight: 400;">These findings, and the increased speed with which they are happening raise an unusual question: how can we potentially harness these organisms and this worm to combat the massive and regular plastic waste creation? As humanity has never experienced such an opportunity regarding plastic degradation, environmental and biology researchers do not currently have answers.</span></p><p></p><p><span style="font-weight: 400;">Dr. Sehroon Khan, of the World Agroforestry Centre and Kunming Institute of Biology, who led the </span><i><span style="font-weight: 400;">Environmental Pollution</span></i><span style="font-weight: 400;"> study, </span><a href="http://blog.worldagroforestry.org/index.php/2017/09/12/scientists-find-fungus-appetite-plastic-rubbish-dump/"><span style="font-weight: 400;">explains</span></a><span style="font-weight: 400;">, “Our team’s next goal is to determine the ideal conditions for fungal growth and plastic degradation, looking at factors such as pH levels, temperature and culture mediums.”</span></p><p><span style="font-weight: 400;">The team found that — though this testing is still in early stages — following two months in a liquid medium, Aspergillus tubingensis had degraded a sheet of </span><a href="https://psiurethanes.com/urethane-resources/polyester-vs-polyether-whats-the-difference/"><span style="font-weight: 400;">polyester polyurethane</span></a><span style="font-weight: 400;"> to the point of near-dissipation. It degenerated the polyurethane better under these conditions than on an agar plate and when buried in soil.</span></p><p><span style="font-weight: 400;">According to the study abstract, “Notably, after two months in liquid medium, the PU film was totally degraded into smaller pieces.”</span></p><p><span style="font-weight: 400;">There is a downside: plastic generally remains on the planet as long as it does due to its inert state. Because it is so often chemically inert, it is also usually sterile. Humans use plastic to package food, build airplane and car parts and even as a component in pacemakers and the primary component in condoms. This means these new microorganisms and organisms with these new abilities are evolving in a way that could eventually threaten the integrity of plastics humans need and regularly use.</span></p><p><span style="font-weight: 400;">The Aspergillus tubingensis fungus was also spotted in the </span><a href="https://www.ncbi.nlm.nih.gov/pubmed/26773134"><span style="font-weight: 400;">airways of patients with lung disease</span></a><span style="font-weight: 400;">, which could have dangerous implications on human health if administered irresponsibly.</span></p><p><span style="font-weight: 400;">Despite health concerns and worries for the future of plastic degradation, these findings reveal creation of environments never before seen on Earth, and once again, the planet’s resilience.</span></p><p><span style="font-weight: 400;">“This could pave the way for using the fungus in waste treatment plants, or even in soils which are already contaminated by plastic waste,” says Dr. Khan.</span></p>
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