Microplastic distribution in the Atlantic and Arctic Ocean through continuous underway sampling

The COntinuous MicroPlastic Automatic Sampling System (COMPASS) was utilized for sampling of microplastic (MP) samples. Developed by Aalborg University in Denmark, COMPASS is a fully enclosed, stainless-steel, plastic-free system designed for continuous, automatic MP sampling (>10 µm). It can operate unsupervised for up to 9 hours, filtering 500 to 1,500 liters of water per hour through stainless-steel filters with mesh sizes of 300 µm and 10 µm (filter diameter: 167 mm). This method provides horizontal distribution data and resolution for MPs. Depending on the length of each transect, a specific number of subsamples were collected. Sub-surface water samples were continuously sampled during steaming at a depth of 4 meters along five transects, covering 1,600 nautical miles from the Norwegian coast to Bear Island in the Arctic Ocean. MP were analyzed using Fourier-transform infrared imaging micro-spectroscopy, revealing concentrations ranging from 7 to 491 items per cubic meter.