Sea ice in the Arctic holds vast amounts of plastic waste, which could be released as the ice thins and shrinks in the rapidly warming region.
Ilka Peeken and her colleagues at the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, analysed microscopic plastic particles in Arctic sea-ice cores collected in 2014 and 2015. The number of particles enclosed in the cores was up to three orders of magnitude higher than reported in a previous study, probably because of improved analytical tools.
The team found 17 polymer types, many of which are used in a variety of common products, such as plastic packaging and cigarette filters. Ice-drift models showed that much of the plastic waste originated from heavily populated areas in the mid-latitudes; but burgeoning commercial shipping traffic in the melting Arctic also contributes to plastic pollution, the team concludes.