Plastic pollution in the aquatic environment has been assessed for many years
by ocean waste collection expeditions around the globe or by river sampling.
While the total amount of plastic produced worldwide is well documented, the
amount of plastic found in the ocean, the distribution of particles on its
surface and its evolution over time are still the subject of much debate. In
this article, we propose a general fragmentation model, postulating the
existence of a critical size below which particle fragmentation becomes
extremely unlikely. In the frame of this model, an abundance peak appears for
sizes around 1mm, in agreement with real environmental data. Using, in
addition, a realistic exponential waste feed to the ocean, we discuss the
relative impact of fragmentation and feed rates, and the temporal evolution of
microplastics (MP) distribution. New conclusions on the temporal trend of MP
pollution are drawn.Comment: 14 pages, 14 figure