南通地区地下水中砷的形态分布特征研究

摘要

Field work was conducted in Nantong City in 2012.Water samples were collected to analyze for monitoring.During the survey,a method based on liquid chromatography-inductively coupled plasma mass spec-trum (LC-ICP-MS)was developed for quantitatively detecting arsenic species distribution in groundwater.Based on this method,the lowest detecting limit for arsenic was 0.1 μg/L.The results of analysis show that arsenic species are mainly by As(Ⅲ),AsB and DMA mainly for organic arsenic,no As(V).The study of arsenic spe-cies shows that the content of arsenic is low in coastal area which mainly by As (Ⅲ),the content of arsenic is high in the Yangtze River area which mainly by As (Ⅲ)and DMA.%2012年开展南通市1∶50000水文地质调查，对监测网内地下水进行采样分析，建立了基于液相色谱－电感耦合等离子体质谱联用测定地下水中砷形态的方法，该方法检出限为0．1μg／L。样品分析表明，南通地区地下水中砷的形态以三价无机砷为主，有机砷以砷胆碱（AsB）和乙基砷（DMA）为主，样品中未检出五价无机砷。通过砷形态研究表明，南通近海地区地下水中砷的质量浓度较低（＜0．5μg／L），主要以 As（Ⅲ）为主，不存在其他砷的形态；近长江地区地下水中砷的质量浓度较高（＞1．0μg／L），砷形态以 As（Ⅲ）和 DMA为主。