A new mechanism for microplastics to enter the food chain

Microplastics enter plankton aggregates, which are then ingested by fish and move up the food chain. Scientists from three laboratories in Toulouse were the first to use atomic force microscopy to study the problem. In work published in the journal Science of the Total Environment, they confirmed the existence of a mechanism where the presence of microplastics favors the aggregation of microalgae and discovered a second, previously unknown mechanism.

Plastic pollution affects all environments. In particular, microplastics enter marine food chains and then travel up to the largest animals and to humans. Interactions with plankton seem particularly important, but are still poorly understood. Microalgae, which make up most of the plankton and the first link in the aquatic food chain, can aggregate under certain conditions. Microplastics cause the formation of these aggregates in which they mix and thus pass into the animals or spread in the depths of the oceans. The heavier aggregates sink instead of floating. Researchers from the Toulouse Biotechnology Institute, bio & chemical engineering (TBI, CNRS/INSA Toulouse/INRAE), the ELiA team of LAAS-CNRS and the Molecular Interactions and Chemical and Photochemical Reactivity Laboratory (IMRCP, CNRS/University of Toulouse/Paul Sabatier) have shown that microplastics reinforce, in two different ways, the formation of plankton aggregates with which they are then mixed. Published in the journal Science of the Total Environment, this work is based on a new methodology, centered around an atomic force microscope (AFM).

[...] read the rest of the news on the CNRS-INSIS website.