Assessing the Seasonal Variability of Water Quality and Heavy Metals Concentration in Sediment, Water, and Fish Muscles of Korotoa River in Bangladesh

The current study reveals the concentration of heavy metals in sediment, water, and three fish species of the Korotoa River in Bangladesh. Two diverse seasons, namely wet (August-September 2021) and dry (January-February 2022) were chosen to compare the seasonal differences of five concerning heavy metals (Cr, Co, Pb, As, and Cd) adjacent to coal mining area using inductively coupled plasma mass spectrometry. Different physicochemical parameters of water quality along with the concentration of heavy metals varied significantly with the seasons. However, the average concentrations of the examined heavy metals followed the downward order of Cr > Pb > As > Co > Cd for both wet and dry seasons. The mean concentration of heavy metals in fish was found higher in Mastacembelus armatus compared with Labeo bata and Amblypharyngodon mola. The values of the researched heavy metals' enrichment factors were reported in the following order: As > Co > Cr > Cd. The pollution load index (PLI) specified that the sediment of the river under study was not seriously contaminated (PLI <1). However, the content of heavy metals in the water was discovered to be much greater than the standards for safe drinking water limits and the preservation of freshwater aquatic life, demonstrating that the river water from this area is unsafe for use as drinking water or for cooking. However, the study suggests relevant authorities should take necessary action to stop further pollution in the study area.