Microscopic particles of plastics are being trapped in Arctic sea ice at record levels according to scientists. And they can trace these tiny pieces of plastic back from where they came — fishing nets, cigarettes, and the massive Pacific Ocean garbage patch.
According to a new study published on Tuesday in the journal Nature Communications, experts from the Alfred Wegener Institute (AWI), Helmholtz Centre for Polar and Marine Research in Germany, have found two to three times more plastic trapped in frozen Arctic sea ice than normally seen in the past.
Examining ice core samples taken from five areas across the region in 2014 and 2015, researchers were able to analyze the chemical fingerprint of the plastics and trace the path of ice floes in order to determine the plastic particles’ origins.
High concentrations of polyethylene particles — used most frequently in plastic packaging — were found in the pacific waters of the Canadian Basin in the Arctic Ocean. As the study’s authors write: “Accordingly, we assume that these fragments represent remains of the so-called Great Pacific Garbage Patch and are pushed along the Bering Strait and into the Arctic Ocean by the Pacific inflow.”
Separately, in the shallow Arctic seas in Siberia, the researchers found plastics mostly linked to paints and nylon. With more shipping and fishing taking place in the Arctic as the seas open up with climate change, these industries are “leaving their mark” on the Arctic through the leftover particles from paint lining ship’s hulls and the nylon fishing nets.
The high concentration of microplastics found in the Arctic are therefore due to both global and local-scale impacts. In total, 17 different types of plastics were found in the ice cores — roughly half of which come from plastics linked to packaging materials, paint, nylon, polyester, and cellulose acetate which is used primarily in manufacturing cigarette filters.
And as the study’s authors note, these plastics may have harmful effects to human and marine life. Because of the microscopic size, they are easily ingested by mammals, fish, and other ocean organisms.
“During our work, we realized that more than half of the microplastic particles trapped in the ice were less than a twentieth of a millimetre wide, which means they could easily be ingested by arctic microorganisms like ciliates, but also by copepods,” said AWI biologist and study author Dr. Ilka Peeken, describing the small phytoplankton and single-celled animals which are a food source for larger animals like fish.
As she explained, the observation is troubling because, “no one can say for certain how harmful these tiny plastic particles are for marine life, or ultimately also for human beings.”
The plastic litter can be trapped anywhere from two to 11 years in the ice, according to Peeken. It’s unclear whether the plastics remain in the Arctic, however, or if they eventually flow back south. Some of the plastic is known to sink down to deeper waters as it clumps together with algae to form a heavier mass.