Pollution status of the Indus River, Pakistan, through heavy metal and macronutrient contents of fish, sediment and water

Concentrations of Ag, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg, together with Na, K, Ca and Mg in 19 species of fish captured from the Indus River, Pakistan, are estimated by the atomic absorption method. Corresponding data for sediment and water from 11 sites along the down-stream route of the river are also reported. Mercury and arsenic concentrations were high (3.920 and 3.072 μg/g, respectively) in the muscle of fish from Guddu barrage as compared with those from other sites. Hetroptirus fossilus showed maximum concentrations of Ag, Cu and Pb in its muscle as compared with other fish. Labeo calbasu from Guddu barrage showed highest As concentration at 3.072 μg/g. Mystus vitatus from Chashma barrage contained maximum cadmium concentration at 0.990 μg/g. Several other fish exhibited elevated levels of metals along the downstream route of the river, a trend exhibited also by the elevated metal contents of sediment and water at Guddu and Lloyd barrages. The study indicated a gross pollution of the sediment and water at various locations of the river, e.g. As (7.452 μg/g) in sediment from Lloyd barrage, Hg (5.710 μg/g) in sediment from Jinnah barrage, Pb (2.709 μg/g) in sediment from Guddu barrage and Mn (0.038 μg/g) in water from Lloyd barrage. The macronutrients showed an inverse relationship with trace metals. Hetroptirus fossilus could be used as indicator species for Ag, Cu and Pb.