Study On Heavy Metal Pollution Of Some Surface Water Bodies In Urumqi

Objective: To determine the levels of four haveay metals (Hg, Cd, Pb, As)in water, sediment and hydrobios from Wulabo, reservoir, Hongyanchi reservoir, and Caiwopu lake. Methods: Pb and Cd were analyzed on atomic absorption spectrophotometer. Fluorescence analysis was used for detecting Hg and As. Results : Cd and Pb were only found in several water samples from the three sites . Higher concentration of Hg was found in water samples from Hongyanchi reservoir while As was found high level in water in Caiwopu lake; In Hongyanchi reservoir concentrations of Hg exceeded the ERL in 40% sites. Although heavy metal concentrations in sediment were not high but they fall within the range of levels observed in industrialized areas of some countries; Different tissues of the common bream from Caiwopu lake showed different capacity for accumulating heavy metals. The highest Pb concentrations was detected in the gill and liver while high concentration of Cd was found in liver. Pb concentrations in liver and gill were significantly (P<0.05) higher than in muscle. Pb concentrations in liver and gillsexceeded the hygienic criteria of China. THE criteria were exceeded by concentrations of Pb in 70% liver samples and 30% gill samples respectively. Concentrations of Cd exceeded the criteria in 90% liver samples. Hg and As levels have no significance in different tissues (P>0.05). Conclusion: Hongyanchi reservoir and Caiwopu lake were slightly polluted by heavy metals. Liver seemed to be the primary organ for heavy metal accumulation. The heavy metal concentration in common bream muscles from Caiwopu lake were below the maximum permissible levels of the National Hygienic Criteria.