Effects of ABS microplastics on microalgae <i>Chlorella vulgaris</i> and <i>Raphidocelis subcapitata</i>

In recent years, there has been a growing interest in the impacts caused by the presence of microplastics (MP) in aquatic environments. The impacts of microalgae exposure to microplastics are still insufficiently investigated and further studies are needed to understand the possible outcomes. In addition, much of the literature has focused on the study of concentrations above those found naturally in the environment and in less toxic polymer matrices. Acrylonitrile-butadiene-styrene (ABS) plastics have a composition rich in additives and, so far, have been studied superficially. In the present study, two of the most commonly used green microalgae species in toxicity assays, Chlorella vulgaris and Raphidocelis subcapitata , were exposed to different concentrations of primary ABS-MP for a period of 6 days. Here, we observed physiological changes in cell growth and chlorophyll a content induced by the concentration and time of exposure to ABS-MP. The lowest concentration did not prove to be potentially toxic to cells, while the highest concentration was the most toxic. Primary consumers, such as microalgae, are essential for the proper functioning of entire ecosystems. Changes in these communities can lead to permanent damage to the communities of organisms at higher levels, so it is essential that their study be done carefully in the face of threats such as MP.