Investigate some heavy metals concentration: lead, cadmium, arsenic and mercury at fresh water fish and snail in Hanoi markets

By atomic absorbance spectrophotometry, the content of heavy metals (lead, cadmium, arsenic, mercure) in freshwater fish and shelfish in the market and in 2 lakes in Hanoi from June to December 2002 was analysed. The contents are: lead 100%, arsenic 98.5%, cadmium 92.9% and mercury 88.6%, they are in the tolerable limits according to 1998 year Vietnam MOH regulation 867/BYT. The contents of various heavy metals are not similar in diverse genera of fish and shelfish. In some genera of fish, arsenic contents are higher than average from 0..68 to 0.601 mg/kg and mercury content 0.053mg/kg. Heavy metal contents in 2 lakes of Thanh Tri district and in diverse markets in Hanoi have not significant differences