Settling and rising velocities of microplastics: Laboratory experiments and lattice Boltzmann modeling.

Microplastics (MPs) have become pervasive in marine ecosystems, potentially causing environmental degradation, impacting ecological function, and posing a serious public health risk. Despite the widespread distribution of MPs, their vertical transport within a water column has limited understanding, representing a key knowledge gap in the development of water quality models to minimize these risks. In this study, 6152 individual particles of six common types of MPs were observed through water column experiments to examine a range of drivers of the vertical velocity of MPs, including particle density and size, biofilm growth, water temperature, and salinity.