Ups and Downs in the Ocean: Effects of Biofouling on Vertical Transport of Microplastics.

Abstract in brief

• The study investigates the hypothesized role of biofouling, which is the formation of biofilms on microplastics, in affecting the vertical movement of microplastics in the ocean and explains the observed size-selective removal of small plastic particles from the surface.
• A new theoretical model was developed that simulates how biofilm growth and water properties influence whether microplastic particles float, sink, or oscillate at various depths, showing that particle size and density are key factors in their vertical transport.
• The model predicts that microplastics tend to accumulate at intermediate depths, with fewer particles at the surface and possibly none reaching the ocean floor, providing insights into the fate of plastic debris and potential exposure risks for marine species at different depths.]