Now, a new review shows that wind can also transport these particles far away-and much faster than water: in the atmosphere, they can reach the most remote corners of the earth from the origin in a few days.
An article published by an international research team in Nature Review on Earth and Environment explains how microplastics enters the atmosphere and then transports it.
At present, 0.0 1.3 to 25 million metric tons of microplastics and nano-plastics are transported thousands of kilometers by sea air, snow, sea fog and fog every year, and in the process, these plastics have crossed countries, continents and oceans. This estimate was made by an international team of 33 researchers, including experts from Alfred Wei Gena Institute, Helmholtz Polar and Ocean Research Center (AWI), Potsdam Institute for Advanced Sustainable Development (IASS) and GEOMAR Helmholtz Ocean Research Center in Kiel.
"Air is a more dynamic medium than water," said Dr. melanie Bogman, co-author of AWI. "Therefore, micro and nano plastics can penetrate into the most remote and largely untouched areas of the earth more quickly. Once there, these particles may affect the surface climate and the health of local ecosystems. For example, the deposition of these deep particles on ice and snow will affect the feedback of ice and snow, reduce its ability to reflect sunlight and promote melting. Similarly, seawater with black spots will absorb more solar energy, which will further warm the ocean. In the atmosphere, microplastics particles can act as condensation nuclei of water vapor, which has an impact on the formation of clouds and, in the long run, on the climate.
How do plastic particles get into the atmosphere?
First, through human activities. Particles produced by tires and brakes in road traffic or waste gas from industrial production will rise into the atmosphere and be blown away by the wind there. However, according to the investigation, there is evidence that a considerable number of these particles are migrated by the marine environment. Preliminary analysis shows that microplastics in coastal areas also entered the ocean through eroded beach sand. The combination of sea fog, wind and waves forms bubbles containing microplastics in water. When bubbles burst, these particles will enter the atmosphere. Therefore, transportation to remote and even polar areas may be due to the combination of atmospheric and marine transportation.
Therefore, it is very important to understand the interaction between the atmosphere and the ocean, so as to determine which particle sizes are transported and how much they are transported. The atmosphere mainly transports small microplastics particles, which makes it a faster transport route, resulting in a large number of deposits in a wide range of ecosystems. As Melanie Bogman explained, "We need to incorporate micro and nano plastics into our air pollution measurement, preferably as part of an international global network". Therefore, as a first step, the first authors of this study, Deni Allen and Bogman, began to collect microplastics samples in air, sea water and ice during their polar expedition last year.
Grasp the cycle of microplastics together.
Understanding and describing the microplastics cycle between the ocean and the atmosphere requires joint efforts. In this regard, in this study, the research team led by the first authors of the paper from university of strathclyde, Glasgow, Deoni Allen and Steve Allen outlined a global strategy to create a seamless and comparable database on the flow of micro and nano plastics between the ocean and the atmosphere. "We still don't fully understand many aspects of microplastics's emissions, transportation and impacts in the atmosphere," said Professor Tim Butler, co-author of the International Association for Science. "This publication reveals the gap in our knowledge and puts forward a road map for the future."
Two task forces of the Joint Group of Experts on the Scientific Issues of Marine Environmental Protection (GESAMP) prepared this study. Professor Sylvia Sander from GEOMAR, the co-author of the research report and a member of the scientific expert group, said: "This study clearly shows that only through the networking of researchers and their data can we fully grasp the impact of the ocean and human beings on the ocean. The great challenges of our time are global. Therefore, we must try our best to seek the answers to urgent questions with all-round and international expertise. This can only be achieved through cooperation. " GESAMP is a consortium of 1 1 organizations belonging to the United Nations, and its goal is to achieve a multidisciplinary and scientific understanding of the marine environment. So far, the network has cooperated with more than 500 experts from all over the world on a series of issues.
Microplastics and nano-plastics in the air are also related to human health. In a recent study in Britain, microplastics was found in the lungs of 13 living people. Bogman said: "This is another reason why we need to include plastics in the air quality monitoring plan." In order to reduce the environmental pollution caused by plastics, the production of new plastics also needs to be gradually reduced on the basis of international treaties, as Bogman and other experts recently called for in a letter to Science magazine.