## 4 Conclusions  
Microplastic pollution and biochar sorption activities have gained significant attention in recent years due to their environmental relevance. Microplastics, tiny plastic particles less than 5 mm in size, pose a threat to ecosystems by acting as carriers for POPs and heavy metals. The sorption capacity of microplastics for contaminants varies depending on polymer type, surface area, and environmental conditions such as pH and temperature. In contrast, biochar, a carbon-rich material derived from the pyrolysis of organic waste, has been extensively studied for its high sorption capacity for contaminants, including heavy metals, organic pollutants, and nutrients. Numerous studies have shown that biochar's porous structure and functional groups enable it to adsorb pollutants more effectively than microplastics. Both biochar and microplastics demonstrated good adsorption behavior according to their respective models, indicating that both materials can remove 4-MBC from water. Since biochar fits the Freundlich model, it suggests that biochar can handle a wide range of pollutant concentrations and continue to adsorb 4-MBC even at higher levels. This makes it a versatile and effective option for long-term water treatment. On the other hand, microplastics fit the Langmuir model, they might be useful in removing 4-MBC from water up to a certain saturation point (until all adsorption sites are filled). This is beneficial when working with lower concentrations of pollutants or when you need a predictable and controlled adsorption process. However, more lab research is necessary to fully examine the absorption of various organic molecules on both materials. For biochar, adsorption studies carried out in the presence of sacrificial electron donor agents may provide important new information about the surface charge and the function of electrostatic interactions in the adsorption process. The presence of plastic waste in the environment impacts how organic pollutants are transported and their toxicity to both aquatic organisms and humans. As bioplastics gain more popularity in everyday use, their environmental release is also growing. Hence, understanding the interactions between different plastics and organic pollutants is highly significant. The results from this research indicate that the occurrence of microplastics and bioplastics in water ecosystems can have a notable influence on the transportation and fate of 4-MBC. The differences between the adsorption behavior of 4-MBC on MPs could occur in the natural water matrices, indicating the need for further investigation, particularly in terms of how the role of different fractions of natural organic matter impacts these interactions. The use of microplastics as sorption materials comes with significant concerns. They are not biodegradable, which means their long-term use may exacerbate plastic pollution. Additionally, they may release the sorbed contaminants under changing environmental conditions, potentially causing secondary pollution. Thus, while microplastics can act as sorbents, their environmental risks make this approach less sustainable compared to alternatives like biochar. Writing--original draft, Methodology, Investigation, J.B.; Conceptualization, Supervision, Writing--review & editing, M.K.I. ; Data curation, Formal analysis, T.S. ; Investigation, Visualization, N.D.; Visualization, Writing--review & editing, J.M.J. ; Validation, Writing--review & editing, S.M. ; Original draft writing, Research, Project administration, Funding acquisition, M.V. All authors have read and agreed to the published version of the manuscript. **Funding:** This research was funded by the Provincial Secretariat for Higher Education and Scientific Research (Project No. 142-451-3519/2023-01/2). **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable. **Data Availability Statement:** The raw data supporting the conclusions of this article will be made available by the authors on request.