陆地水中的砷一般含量很低(<10ppb), 用通常的Ag—DDTC法很难测出。原子吸收法虽然灵敏度高,但必须要有砷化氢捕集器和砷的原子化特殊装置。为了阐明陆地水中砷的溶存状态,著者利用氢氧化锆与砷生成的共沉淀,通过STB(四氢硼酸钠)还原,使三价砷和五价 Arsenic in terrestrial waters is generally low (<10 ppb) and is difficult to measure with the usual Ag-DDTC method. Although atomic absorption method has high sensitivity, it is necessary to have arshanide trapping device and arsenic atomization special device. In order to elucidate the arsenic dissolution in terrestrial water, the authors used coprecipitation of zirconium hydroxide with arsenic to reduce trivalent arsenic and pentavalent arsenic by STB (sodium tetraborate)