Not even the The Arctic Ocean is immune to the relentless growth of microplastic pollution. In a new study that analyzed samples of sediment cores, researchers quantified how much of the particles have been deposited since the early 1930s. As scientists have shown elsewhere, the team found that microplastic pollution in the Arctic has grown exponentially, in line with the growth in plastic production – now reaching a trillion pounds a year, with the global amount of plastic waste expected to triple by 2060.
These researchers analyzed the seawater and sediment in the western part of the Arctic Ocean, which accounts for 13 percent of the total surface area. But in that very region, they calculated that 210,000 tons of microplastic, or 463 million pounds, have accumulated in the water, sea ice and sediment layers that have built up since the 1930s. In their study published in the newspaper last week Scientific progress, they cataloged 19 types of synthetic polymers in three forms: fragments, fibers and sheets. That reflects a dizzying array of microplastic sources, including fragments from broken bottles and bags and microfibers from synthetic clothing.
Overall, the team found that levels of microplastic in the Arctic Ocean sediments double every 23 years. That echoes a previous study of ocean sediments off the coast of Southern California that found concentrations doubling every 15 years. Other researchers have found an exponential increase in contamination in sediments of urban lakes.
The problem is likely to get worse, lead author Seung-Kyu Kim, a marine scientist at Incheon National University, told WIRED by email. “Microplastic imports into the Arctic have increased exponentially in recent decades, with an annual rate of increase of 3 percent,” Kim writes. “The mass production of plastic with an annual increase of 8.4 percent – coupled with inefficient waste management systems – is expected to further increase the load of plastic entering the ocean in the coming decades, and so the plastic entering the Arctic will increase proportionally. “
The atmosphere is also increasingly contaminated with microplastics. According to one calculation, the equivalent of hundreds of millions of disintegrated plastic bottles could fall in the United States alone. a study of a peat bog in the Pyrenees found that less than five atmospheric microplastics were deposited per square meter of land every day in the 1960s. It’s more like 180 now.
This new Arctic paper “helps show that any increase in production is matched in the environment,” said Steve Allen, a microplastics researcher at the Ocean Frontiers Institute who did the peatland study. “And as more research on human exposure comes to light, I think the increase will be shown in human bodies as well.”
Microplastics move easily between different environments. A previous study found 14,000 microplastics per liter of Arctic snow, originating from European cities. Microplastics also arrive in the Arctic by sea: when you wash your clothes, hundreds of thousands or even millions of synthetic fibers break down and wash off to a wastewater treatment plant and eventually to the ocean. Currents then transport microplastics to the Arctic, where they whirl around and eventually settle in the sediment. Allen and other scientists reported in May that a single recycling facility could emit 3 million pounds of microplastics a year — and those were numbers for a brand-new factory that filtered runoff water.