Abstract: Arsenic (As) is a widely distributed heavy metal element, with the main forms of inorganic arsenate and arsenite in natural waters. Dissolved organic matter (DOM) in natural waters will be complexly interacted with As. It is significant to explore the complexation between DOM and As with the aim to understand the migration and transformation of As in waters. To clarify the complexing mechanism, influencing factors and analytical methods of As and DOM in waters, we focused on following aspects: (1) The source and transformation process of different forms and valences of As in waters; (2) The direct complexation of As with DOM and the indirect complexation with the participation of metal ions; (3) The effects of pH, temperature and salinity on As-DOM complexation; (4) Comparing the separation and analysis technologies of As-DOM complex, such as chromatography, spectrometry and combination of various analysis methods; (5) Summarizing the shortcomings of the existing research and the direction of the future research. The discussions of AsDOM complexation provide theoretical support for further research on As migration and transformation in waters and AsDOM complex.

Key words: arsenic, dissolved organic matter, interaction, analytical method.