Assessing Toxicological Impacts Of Water Quality On Fish In The Dasu Region Of Indus River

Abstract

The physicochemical analysis of water samples from eight sampling locations, including upstream and downstream areas of the Dasu Hydropower Project (DHPP) and selected tributaries, revealed compliance with World Health Organization standards for parameters such as pH, electrical conductivity, total dissolved solids, despite elevated turbidity levels. Similarly, concentrations of heavy metals in water samples, including aluminum, arsenic, barium, cadmium, cobalt, chromium, copper, manganese, molybdenum, nickel, lead, Selenium, Strontium, and zinc, met WHO standards. Examination of fish samples from the same locations confirmed compliance of selected heavy metal concentrations with WHO standards, supporting the safety of fish consumption in the studied region. Noteworthy findings include the prevalence of nickel in fish kidneys, emphasizing its bioavailability, and a distinct order of metal accumulation in fish liver, with molybdenum exhibiting the highest accumulation. Further analyses revealed the vulnerability of fish organs to metal accumulation, with the liver being most susceptible according to the Metal Pollution Index (MPI) (liver MPI: 8.14, kidney MPI: 6.71), particularly in tributaries. Additionally, oxidative stress analysis indicated adaptive responses in antioxidant enzyme activities, suggesting a link between higher metal pollution and bioaccumulation. These results underscore the need for continued research to understand ecological consequences and potential health risks associated with heavy metal bioaccumulation in aquatic ecosystems surrounding the Dasu Hydropower Project.