Convergence zones of coastal waters as hotspots for floating microplastic accumulation.

This study examines microplastic (MP, 1-5 mm) densities in convergence zones in a coastal sea, the Seto Inland Sea, comparing them to those of non-convergence zones and other areas. Notably, Seto convergence zones exhibit MP densities 40 to 300 times higher than non-convergence zones, with an extraordinary density of 3.7 ± 6.