A surface-floating, macroplastic item made of a decapod and macroplastic material, was taken from the German research vessel SONNE, during Expedition SO268/3, which crossed the North Pacific Ocean between Vancouver and Singapore in summer 2019. Gritta VeitKhler Senckenberg. Credit: Grittaveit-Khler SenckenbergAccording to a study published in Science by scientists from Germany, Norway, and Sweden, current levels of plastic emission globally could have consequences that are impossible to reverse. The authors state that plastic pollution is a worldwide problem and that actions to reduce plastic emissions to the environment are the "rational policy response".Plastic can be found all over the globe, from deserts and mountains to deep oceans or Arctic snow. According to 2016 estimates, plastic emissions to the oceans, lakes and rivers of the world ranged between 9 and 23 million metric tonnes per year. A similar amount was emitted onto land each year. If business-as usual scenarios are applied, these estimates will almost double by 2025.Matthew MacLeod (Professor at Stockholm University, lead author of the study) says that plastic is deeply embedded in society. It leaks into the environment everywhere even in countries with good waste management infrastructure. He claims that plastic pollution is on the rise despite increased awareness among scientists and the general public about it in recent years.Mine Tekman, a doctoral candidate at Germany's Alfred Wegener Institute and co-author of this study, isn't surprised by the discrepancy. Plastic pollution is more than an environmental problem. It is also a political and economic issue. She believes that current solutions, including recycling and cleanup technologies are inadequate and must be addressed at the root of the problem.The world supports technological solutions to recycle and remove plastic from our environment. We believe that if we properly segregate our plastic trash, it will all magically be recycled. Technologically, plastic recycling has limitations. Countries with good infrastructures have been sending their plastic waste to poorer countries. To reduce emissions, drastic measures are required, such as limiting the production of virgin material to increase its value and prohibiting the export of plastic waste to countries with better recycling facilities," says Tekman.During expedition SO268/3, the German research vessel SONNE crossed the North Pacific Ocean between Vancouver and Singapore in summer 2019. Roman Kroke UFZ. Credit: Roman Kroke UZPollutant that is difficult to reverse in remote areas of the environmentWhen plastic is released in excess of what is removed by cleanup efforts and natural environmental processes, it accumulates in the environment. This process is called weathering.We have made great strides in our understanding of the processes that lead to plastic weaving. Hans Peter Arp (researcher at the Norwegian Geotechnical Institute, NGI) and Professor at Norwegian University of Science and Technology, NTNU), who co-authored the study, says that weathering changes the properties of plastic pollution. Arp says that plastic exposure will only increase because of the slow rate at which it degrades and its inability to stop accumulation. Because of its persistent emissions and environmental persistence, plastic is a "poorly-reversible pollutant".Co-author Annika Jahnke is a researcher at Helmholtz Centre for Environmental Research and Professor at RWTH Aachen University. She explains that remote environments are especially at risk.Plastic debris can't be cleaned up in remote areas. Weathering large items of plastic will result in large quantities of micro- and macroplastic particles, as well as the leaching of chemicals that were added to the plastic or other chemicals that have the ability to break down the polymer backbone. Plastic in the environment is constantly changing and moving, with increasing complexity and mobility. It is difficult to predict where it will accumulate and what it might cause.After fermentation to biogas, soil fertilizer and fermentation of food waste in Norway, plastic residue is removed. Heidi Knutsen and Caroline Hansen, NGI. Credit: Caroline Hansen & Heidi Knutsen (NGI).The tipping point for irreversible environmental destructionPlastic pollution, in addition to the environmental damage it can cause by its own entanglement and toxic effects, could also be combined with other environmental stressors in remote locations to create wide-ranging or global effects. This new study offers a variety of scenarios for possible effects. These include an increase in climate change due to disruptions in the global carbon pump and biodiversity loss in oceans where plastic pollution acts like an additional stressor.The threat that plastic emissions today could have a global-scale, unreversible impact in the future is viewed by the authors as "compelling motivation" to take targeted actions to reduce carbon emissions."Right now we are adding to the environmental pollution with poorly reversible plastic. We don't yet see any evidence of serious consequences. However, if weathering plastic causes a very bad effect, it is unlikely that we will be able reverse it." MacLeod warns. The environmental damage caused by persistent plastic pollution could be severe. It is sensible to take immediate action to reduce plastic pollution.See more Video: A sweet solution for plastic pollutionFurther information: M. MacLeod, Stockholm University, Stockholm, Sweden el., "The worldwide threat from plastic pollution," Science (2021). Information for Journal: Science M. MacLeod, Stockholm University, Sweden, el al. "The global danger from plastic pollution," (2021). science.sciencemag.org/cgi/doi 11.26/science.abg5433
