Up to 80,000 tons of plastic waste are floating in the garbage vortex of the Northern Pacific: it is the best-known example of such waste gyros that can be found in all major seas. However, a large part of the garbage in the "North Pacific Garbage Patch" seems to originate directly at sea and does not come from sources on land. This is shown by a random evaluation of the objects floating there, which Laurent Lebreton from The Ocean Cleanup and his team present in "Scientific Reports".
During a measurement trip, LeBreton and Co had more than 570 kilograms of garbage from the sea, which were distributed over 6100 objects with a size of more than five centimeters. If possible, the working group tried to determine the origin of the objects, provided that the lettering was to be deciphered. Around a third of the products collected was no longer identifiable: sun and salt water had destroyed them so far that it was no longer recognizable what it was or where the waste came from.
Another quarter, on the other hand, accounted for things such as fish boxes, spacers from oyster farming or eel traps, which could clearly be assigned to fishing. Another three percent included floats, buoys and nets, which also came from fishing boats. These were also relatively heavy objects: they accounted for one fifth of the collected weight.
With 232 objects, Lebreton and Co were still able to determine the origin: two thirds of the garbage came from Japanese and Chinese sources, which fishing intensively in the Pacific. Almost a tenth was of South Korean origin, 6.5 percent indicated the United States. This was followed by Taiwan and Canada. Modeling of the oceanic currents and garbage transport then suggested that it is ten times more likely that waste materials in the North Pacific garbage strudel will deliberately or accidentally go overboard as they are rinsed on land on land and drift into the central pacific.
The survey confirms the findings of previous expeditions, the scientists write. Their random samples had shown that up to 75 of the plastics in the region came from fishing. The Food and Agriculture Organization (FAO) already estimated in 2018 that 640,000 tons of lost or abandoned fishing nets enter the oceans every year. However, as a result, the fishing fleets are affecting their own industry. In these so-called ghost nets, numerous sea creatures get tangled and die in them, until the nets become too heavy and sink into the depths.
