Characterization and Removal of Microplastics in Landfill Leachate Treatment Plants in Istanbul, Turkey

This study was carried out to determine the abundance, size, and type of microplastics (MPs) in landfill leachate of Kömürcüoda and Odayeri sanitary landfills in Istanbul. Within this framework, membrane bioreactor (MBR)-ultrafiltration (UF) and nanofiltration (NF) samples were collected to determine the concentration of microplastics in both landfill leachate treatment plants (LLTPs). The highest suspected microplastic concentrations were determined to be 196, 147, and 183 particles/L in the mixed liquor sludge from a membrane bioreactor (MBR) in Kömürcüoda LLTP and aerobic and anoxic basins in Odayeri LLTPs. The main particle color detected in Kömürcüoda LLTP was transparent, followed by black, whereas transparent and blue were dominant in the Odayeri LLTP. In the effluents of UF and NF units of Kömürcüoda LLTP, the microplastic concentrations were 7.24 particle/L and 2 particle/L. The results show that UF and NF efficiently removed microplastics at 99%. In the effluent of the UF unit in Odayeri LLTP, approximately 96% microplastic removal was achieved. According to these results, the most common microplastic type in all units was fiber and the principal sizes were between 500 and 999 and 1000 and 1999 µm at all sampling points.