The proliferation of
microplastics in aquatic ecosystems has become an important environmental issue in recent years. The gradual disposal of plastic waste, the lack of standard diagnostic methods and the removal of
microplastics have made it pervasive in the environment.Methodology: In this research, water sampling was performed on both surface and deep forms of
municipal wastewater of
Bandar Abbas water treatment plant during one year (۱۳۹۹-۱۳۹۹), seasonally. The samples were passed through sieves with springs of ۵۰۰, ۳۰۰, ۱۰۰ and ۳۰ μm and then the organic matter in them was digested with hydrogen peroxide and the
microplastics were separated by density-based separation method with sodium chloride salt and by stereomicroscope and FTIR spectrometer investigated.The results showed that in all seasons, particles larger than ۵۰۰ microns had the highest number in the sewage inlet, in other stations, the highest number was related to ۳۰۰-۵۰۰ micrometers and ۱۰۰-۳۰۰ microns. In all seasons of the year, the average number of macro and
microplastics from wastewater to wastewater showed a decreasing trend. The decreasing trend of macroplastics was higher than
microplastics particles, so that the effluent of
municipal wastewater was not macroplastic (> ۵۰۰ microns). In all stations (except the input station), the highest number of
microplastics was related to particles with a size of ۳۰۰-۵۰۰ micrometers, and the reason could be due to the lack of a proper mechanism for removing microplastics. Mand ۲ showed higher efficiency in reducing and removing
microplastics with the size of ۳۰۰-۵۰۰ and ۱۰۰-۳۰۰ microns than other stations. About ۳۰% of the microplastic samples belonged to polyethylene and ۳۰% to polypropylene. The rest of the identified
microplastics belong to the family of polystyrene, polyester and polyacrylate, which are mostly due to the washing of textiles, disposable dishes and materials used in cosmetics.At present, treatment plant networks are not specifically designed to remove
microplastics from wastewater, and in the process of treating treatment plants, the removal of
microplastics depends on their density, because
microplastics are low-density and can float superficially. Deleted them. Thus, considering the amount of
microplastics in municipal wastewater, it is necessary to conduct research on the amount of
microplastics released by the wastewater treatment plant and other possible sources of emission and their contribution to microplastic pollution in water sources.
