Mercury(Hg),arsenic(As) and selenium(Se) are ubiquitous in the environment and exist in a variety of species,which have great influence on their transport,bioaccumulation and toxicity.This review presents the recent research progress in speciation analysis of Hg,As,and Se,with emphasis on enhanced cold vapor generation as interface for liquid chromatography and atomic spectrometry,speciation of volatile species in gas phase,and isotope dilution technique to improve the precision and accuracy of speciation.Hyphenated techniques to characterize the complexes of Hg and As with phytochelatins and chromatographic separation coupled with multi-collector-inductively coupled plasma mass spectrometry to measure species-specific isotopic ratios,are also briefly discussed.
