CHAPTER 8: Heavy Metals Distribution in Surface Water Samples of Taihu Lake, China Check Access

Water quality monitoring can provide scientific reference for the utilization, management and protection of water resources. Chemical contaminations in lakes can cause algal bloom and lead to declining biodiversity and ecosystem function of lake aquatic systems, and also affect the regional economic and social development. Taihu Lake is one of five largest freshwater lakes in China, and this lake has been facing serious eutrophication problems in recent years. Water quality of Taihu Lake has been decreasing every year since the 1990s, and currently the lake is severely polluted by organics, nutrients and various heavy metals. To better understand the heavy metals pollution in Taihu Lake, a systematic investigation was carried out to study this. Forty-nine water samples were collected from Taihu Lake in February 2010 and analysed by ICP-AES. The results show the following. (1) Surface water samples in East Taihu Lake have the lowest heavy metal concentrations, except for the lead (Pb) concentrations, which exceeded the Chinese fishery water quality standards. In East Taihu Lake, the manganese (Mn) concentration exceeded Chinese drinking water standards in only one sample. (2) In North Taihu Lake, the concentrations of chromium (Cr), cadmium (Cd), zinc (Zn), copper (Cu) and arsenic (As) were low, which meet or are better than Grade II surface water standards. However, Pb concentrations in four samples meet Grade III surface water standards. (3) In West Taihu Lake, concentrations of Cd in six sampling locations were identified as being inferior to Grade V surface water.