Microplastics in River Sediments Nearby to a Sewage Treatment Plant: Extraction, Processing and Characterization Assessment

Microplastic pollution is an emerging concern for the aquatic environments as it has been reported in many rivers, lakes, reservoirs and aquatic organisms around the globe. Rivers behave as a temporary sink for microplastics and also serve as a medium through which these particles reach the ocean. This study shows the river transport of microplastics originating from sewage effluents. Six different locations were sampled, including upstream, downstream, and at the sewage disposal point. H2O2 was used to clean the raw samples and then separation was done using NaCl solution. FTIR technique was used for the polymeric characterization of suspected microplastics. The highest concentration of microplastics was reported near the sewage disposal point as 477 MPs/kg. White and transparent were the most predominant microplastics found in all the samples with 0.3 to 1 mm in size. PE and PP were the most common microplastic polymers found in each sample. This work provides significant information about the distribution of microplastics in freshwater sources near the sewage treatment plant. Furthermore, this study highlights the need for more research related to the microplastics found in rivers.