Seasonal Variations in Water Quality and Microplastic Contamination in the Surma River, Bangladesh: Implications for Aquatic Health and Human Safety

Abstract

Water quality parameters (WQPs) are an important aspect of a significant role in addressing the issue of aquatic animals and human health hazards. There is increasing concern that some microplastics (MPs) are being disadvantaged and directly affected by aquatic organisms and potential health risks. Research has consistently shown that physiochemical parameters are lacking in the Surma River. This study examines the seasonal fluctuations in water toxicology and the effects of MPs on freshwater ecosystems in the Surma River. Data were gathered from three locations during the monsoon, winter, and summer seasons of 2023–2024 at 4-month intervals. The analysis revealed concerning WQPs, water quality index (WQI), and pollution index values, indicating serious threats to aquatic life. FTIR microscopy detected MPs, with fibers being the most common (55%), followed by fragments (28%), films (10%), and foam (6%). The highest pH recorded was 8.44 at Station 1 during the summer, while the lowest pH fell to 7.02 in winter. Station 3 exhibited the lowest WQPs, reaching a minimum of 0.15 in winter. The monsoon season showed the most pronounced changes, with heightened pollution levels due to flooding, which diminished habitat suitability. The presence of MPs adds complexity to water quality by introducing harmful pollutants that accumulate in fish, threatening both aquatic ecosystems and human health. These results highlight the critical need for robust water quality management strategies and further research into the ecological and health effects of MPs in freshwater environments. This study enhances our understanding of the seasonal variations in water toxicity and the contribution of MPs to water pollution.