TOKYO -- Microplastic waste floating in the Pacific Ocean is expected to increase approximately twofold by 2030 and exceed fourfold by 2060, causing potential harm to the ecosystem, a study by a Japanese team has shown.
Microplastics are small pieces of plastic less than 5 millimeters in length -- often a product of discarded plastic breaking down. Upon entering the ocean, they tend to float near the surface for several years. When consumed by fish and other animals, microplastic waste causes inflammation and eating disorders in marine life.
In 2016, researchers from bodies including Kyushu University and Tokyo University of Marine Science and Technology collected seawater from areas in the Pacific stretching from the Antarctic to Japan. They then measured microplastic fragments in the open sea measuring at least 0.3 millimeters in length. Next, they used computer simulations to predict shifts in the amount of microplastic waste over the next 50 years. The team took into account the results of a U.S. study and ocean currents in making their estimates.
According to the results, the amount of microplastic waste floating in the waters near Japan, the central part of the North Pacific and other areas in the summer will increase annually. The research team pointed out that some ocean areas with about 250 milligrams of microplastic waste per cubic meter in 2016 will see an increase to 500 milligrams by 2030 and exceed 1,000 milligrams by 2060, in the summer.
Kyushu University professor Atsuhiko Isobe, an expert in the field of physical oceanography who took part in the study, explained the need for further research as "results show the effects microplastic waste smaller than the size of mesh have on animals."
The researchers published their findings in the British scientific journal Nature Communications.
(Japanese original by Kazuhiro Igarashi, Science & Environment News Department)