## 1 Introduction  
With the large-scale usage of plastic, the poor management of plastic waste now represents one of the main threats to the environment, and contemporary society faces a worldwide plastic pollution crisis [1]. While reports concerning plastic pollution have been available since the 1970s, the scientific community only started to show interest in this topic at the start of the 21 st century, making the presence of microscopic plastic particles in the environment a relatively recent area of research [2, 3]. Based on the latest report by Plastic Europe, in 2021, global plastic production increased by 4%, which amounts to more than 390 million tons, implying that it remains in high demand on the market [4]. The wide application of plastics in industry, transport, medicine and commercial and household activities, as well as the poor management of plastic waste, has led to the fact that the residues after the degradation of these materials, better known as micro- and nano-plastics, have emerged as contaminants in the environment [1, 2, 3]. In addition to moves by decision-makers to limit the use of plastic in everyday human activities, as well as the efforts of the scientific and professional communities to find optimal solutions for reducing pollution and suitable substitutes for plastic materials, several hundred million tons of plastic products are still produced every year [4; 5; 6; 7; 8; 9]. The research carried out so far all over the world, has shown that in all parts of the environment, one can find the remains of plastic in sizes that fall between 1 and 1000 \(\upmu\)m; in recent times, plastics in this size range have been most often defined as microplastics (MPs). The range of polymers that are included in this group is very wide, and the effects of polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), polyethylene terephthalate (PET) and polystyrene (PS) on the environment and in various parts of the natural world are the most investigated [5; 6; 7; 8]. Microplastic particles are detected in different shapes, sizes, colors and densities, and possess other characteristics, depending on their origin in the environment, their age, the process they went through during their production, their application and the environmental conditions in which they occur [10]. Any change in the basic polymer during production (addition of additives, plasticizers), as well as during their lifetime in the environment, will affect the properties and behavior of MPs in the environment, their interaction with other compounds (e.g., organic and inorganic pollutants), and their potential harmful impact on living organisms and human health [5; 6; 9]. In water environments, MPs have the potential to become vectors for different organic and inorganic pollutants and pose a significant problem [9; 11; 12; 13]. From the environment, MPs can sorb and accrue organic pollutants and heavy metals due to their hydrophobic properties and their large surface areas [14; 15; 16; 17]. The interaction between MPs and organic pollutants has been extensively researched by other authors. Besides the MP properties and concentrations, there are other factors, shown in Figure 1, that influence the sorption capacity of these pollutants, such as temperature, pH, ionic strength, dissolved organic matter content, solubility and many others [17; 18]. The presence and behavior of organic pollutants in water environments, particularly those that are ionizable, are often dependent on pH. Additionally, the interaction between cationic, anionic and zwitterionic molecules with the plastic surface is different depending on the MP surface [13]. In terms of different factors influencing the sorption of pollutants, pH has been highlighted as the most significant, since, in many cases, it can affect both the sorbent surface properties and the nature of the sorbate.