Study On The Pollution Character Of Heavy Metals In Water Environment And Economic Fishes From Poyang Lake

Concentrations and distribution characteristics of four heavy metals (Cu, Zn, Pb and Cd) in water, surface sediment and fishes sampled from Poyang Lake were studied by analysis of these four heavy metals in lake water, surface sediment and fishes’ organs (swim bladder, fish scales, fins, gills, hepatopancreas), bone as well as musle tissues. Besides, the concentration coefficient of fishes for heavy metals were discussed, conbining with the target hazard quotient (THQ) and hazard index (HI), the health risk of fish tissues in Poyang Lake were assessmented. On this basis, the correlation of heavy metals in fish with that in the environment was illustrated. The main conclusions drawn are as follows:(1)The values of heavy metals in water were generally low, while the level of heavy metal pollution in sediment were much more serious, the potential risk index were decreased in the order of Cd> Cu> Pb> Zn. The total potential risk index in different region were decreased in the order of estuary> aquaculture are> east lake> north lake> south lake. Besides, the pollution indexes of fishes were lower than0.6, in which40%were0.2～0.6, belong to light pollution level.(2) The heavy metal contents of fishes at different water depth showed certain vertical distribution characteristics. All of the heavy metal elements showed the regulation of carnivorous fishes> omnivorous fishes> herbivorous fishes. In additionally, different organ of fish had different affinity to heavy metal ions, which heavy metal ions first absorb on fish scale and gills, while muscle tissues were not the main target organ absorbing heavy metals.(3)The concentration coefficient of fishes for heavy metals were decreased in the order of Cu> Zn> Pb> Cd, the mixture of heavy metals poses no non-cancer hazard to human beings for the values of HIsF was0.093～0.260, not exceeding the risk control standards1. While the contribution rate of Cu to HIsF was47.60%～60.63%, which should be pay more attention.(4)Heavy metal contents in fishes were positive correlation with that in water, while the value was significantly influenced by the concentration of heavy metals in sediment instead of that in water.