Even the Arctic can’t escape plastic pollution. Scientists gathered ice samples from five distinct regions in the Arctic Ocean, and some of those samples contained over 12,000 microplastic particles per liter of ice – a record-breaking amount. All told, they uncovered 17 different kinds of plastic, including paints and packaging.

Scientific research at a melting pond in the Arctic

A team of 9 scientists at Alfred Wegener Institute recorded record levels of microplastics, or plastic fragments between a few micrometers to under five millimeters big, in sea ice collected in the Arctic. They gathered these samples aboard the research icebreaker Polarstern in 2014 and 2015. They utilized a Fourier Transform Infrared Spectrometer to scrutinize the ice samples layer by layer to light up microparticles; particles reflect varying wavelengths depending on their ingredients so the scientists could determine their substances.

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Their methods helped them discover minuscule particles. Scientist Gunnar Gerdts, who runs the laboratory where the researchers carried out measurements, said in a statement, “In this way, we also discovered plastic particles that are tiny 11 microns in size. This is roughly a sixth of the diameter of human hair and was also the key reason why, with more than 12,000 particles per liter of sea ice, we were able to detect two to three times higher plastic concentrations than was the case in a previous study.”

Arctic sea ice with a melting pond under a cloudy sky

67 percent of the particles in the ice samples fell in the 50 micrometers and below category: the smallest one. Biologist Ilka Peeken said, “We found out in our study that more than half of the microplastic particles trapped in the ice were smaller than one-twentieth of a millimeter and thus easily eaten by Arctic microorganisms such as crayfish, but also copepods.” This is concerning, she said, because “so far no one can say to what extent these tiny plastic particles harm the sea dwellers or end up even endangering humans.”

The journal Nature Communications published the research this week.

+ Alfred Wegener Institute

+ Nature Communications

Images via Tristan Vankaan, Mar Fernandez, and Stefan Hendricks