Preliminary study on the behavioral response of zebrafish to the presence of methionine and polypropylene residues in water

When it comes to pollutants in the aquatic environment, there is a wide variety of products, from fibers and plastics to food and medicinal compounds and their by-products. Pollutants have been an area of interest for decades and are becoming more popular with each passing year, whether their presence and effects are studied separately by class or in combination. Among all, polymeric materials are in the center of attention, and their presence in the environment has long been established with studies on their harmful effects. Improper disposal of pharmaceutical materials is just one of many ways that lead to their accumulation in water and soil. The worldwide spread in the environment of polymeric materials, as well as pharmaceutical pollutants is described by the literature, but also the effects of these two materials separately in terms of the behavior of zebrafish (Danio rerio). In this paper, we studied the "joint effect" of one polymeric material (polypropylene) and one pharmaceutical product (methionine - one of the essential aminoacids of the body, with antioxidant properties and multiple uses in the pharmaceutical field). Although we did not find many significant differences in terms of behavior, one aspect worth noting was the anxiolytic-like effect of microplastic on the social, and stress related behavior of zebrafish.