Neuston-net tows and microplastic concentrations and inventories in the Chukchi and Beaufort Sea during the cruise MR22-06C of the R/V Mirai of JAMSTEC

The distribution of microplastic in the open ocean of the Arctic Ocean is largely undocumented. Substantial numbers of studies on microplastics have been reported in the Pacific and Atlantic Oceans, yet very few data are available in the polar oceans. In the present study, we conducted microplastic surveys along the cruise track to fill gaps in the Arctic Ocean.
Floating microplastic samples were collected at 19 stations using a neuston net with a square mouth opening of 75 cm height and 100 cm width, equipped a 333 micro-m mesh opening net with a 100 micro-m mesh net at the cod end. The net was released from the ship's starboard side using a crane and towed for 20 min at a speed of 1-2 kn in the upper 0.4 m of the sea surface. A single sample was collected at station 13. Duplicate samples were collected at each of the remaining 18 stations by repeating the net towing. A flow meter was installed at the net mouth to estimate the volume of water filtered during each tow. The collected samples were fixed with 5% formalin and stored at room temperature until analysis.