Potential sources and transport of atmospheric microplastics in the North Atlantic Ocean

The present study held in the frame of the JPI-Oceans FACTS examines the occurrence and long-range transport of microplastics (MP) in the North Atlantic Ocean. During a research cruise in 2021 seven transects along the Norwegian coast up to the Bear Island were actively sampled and the performance of two different sampling devices was evaluated. MP analysis and mass quantification was conducted using Py-GC/MS method. With careful reference to available field and laboratory blank values, MP was detected even in remote Artic areas with concentrations up to 37.5 ng MP m-3 and a clear predominance of the PET cluster. In addition, car tire tread, and clusters of PS, PP, and PUR were detected more often. Using the Lagrangian particle dispersion model FLEXPART, an attempt to reconstruct the origin of the air masses was made and to gain information about the origin of the measured MP by quantify different source contributions (sea-spray, mineral dust, road dust, agriculture). In this context, the resuspension of MP from the ocean into the overlying air layers appears to be a relevant source. Likewise, the long-range transport of PET particles appears to be substantial. The range of polymers detected, but also the risk of contamination, was closely linked to the particular sampling method used.