This paper reviews the recent research advances in heavy metal speciation in the sediments of lakes, and summarizes the morphological speciation characteristics of heavy metals in sediments from typical lakes in China. The percentages of heavy metals that can be extracted from sediments are different:the extractable Pb accounts for more than 50%, extractable Cd for more than 70%, and other extractable elements for much small percentages, most of which are in residual states. Different continuous extraction methods including Tessier, original BCR and improved BCR are compared. It is shown that the improved BCR has the best extraction effect, thus is being used widely, but its shortcoming is long extraction time. Using ultrasonic and microwave assisted method can greatly shorten the extraction time. The paper also describes the factors that influence heavy metal speciation in sediments, such as pH, oxidation reduction potential, particle size, organic matter content, etc. The advantages, disadvantages and applicable scopes of various evaluation methods are discussed based on speciation and biotoxicity. Finally, future extraction and analysis technology for heavy metal speciation in sediments and corresponding evaluation methods are prospected.

lake  /  sediment  /  heavy metal speciation  /  morphology extraction