Abundance and characteristics of microplastics in the landfill leachate of Amin Bazar, Dhaka: A potential risk to aquatic environments

Abstract

Plastic pollution has become a growing environmental and human health issue over the last decade. The landfill sites of developing countries receive a variety of waste, including plastic, organic, and even hazardous waste. Due to biogeochemical cycles and photooxidation, plastic wastes become microplastics (MPs), which enrich the MP abundance in landfill leachates. MPs have been found in leachate, surface water, and groundwater, with an average value of 270 ± 13, 2090 ± 100, and 647 ± 22 MP/L, respectively, at the largest landfill sites in Bangladesh. The most common shape was fragment, and most MP had sizes between 0.1 and 0.5 mm. Eight distinct colors of MPs were found in the samples; the most common colors in leachate were blue and red, while transparent was found in large quantities in both surface and groundwater. The Fourier transform infrared (FTIR) analysis revealed that low-density polyethylene (LDPE), high-density polyethylene (HDPE), polyethylene terephthalate (PETE), nitrile, polypropylene (PP), and nylon were the predominant polymers in the samples. Due to improper management and poor engineering conditions at landfill sites in developing countries, leachate MPs may translocate to nearby surface water and groundwater. The results explored a new dimension of MP pollution in Bangladesh and urged the development of innovative treatment facilities that may reduce the potential threat of MPs to the environment.