Pharmaceuticals, pesticides and other xenobiotics, including their metabolites and transformation products, became a well-known topic in fields of ecology and public health. Along with the rapid rise of human population rose the consumption of xenobiotics and they are, therefore, widely detectable in soils of populated areas and environmental waters. Besides human consumption, xenobiotics are being largely used in veterinary, mostly with meat industry farms. However, xenobiotics are not the only emerging contaminants of chemical industry. Microplastics have lately been getting a lot of attention in media as well. Microplastic particles are not uniform by their shape nor their chemical structure, and therefore they represent an additional and a complex ecological problem. Since these contaminants are usually found floating in a mutual medium, it is essential to examine their interactions. Standard preliminary examination of xenobiotics that are surely found in the environment are toxicity determination tests. Luminescent bacteria Vibrio fischeri were used in this research paper. Besides toxicity testing other examinations were conducted as well. Concentrations of anthelmintics were monitored over time after exposure to different environment conditions. Transformation and degradation were determined through chromatography analysis, as well as potential adsorption to microplastic particles. It was concluded that anthelmintics mebendazole, albendazole and febantel are not toxic at 3 mg/L concentration. Just as well, it was proven that all three anthelmintics indeed decompose or transform to other structural shapes under certain conditions. Also, it was shown that all of them have adsorption affinity and that microplastics can contribute to the process of transformation or degradation of these compounds.