砷在自然界很少以游离状态存在,多存在于金属或硫的化合物中。砷的化合物较广泛地应用于工农业生产部门。游离砷毒性微弱,甚至认为无毒,而砷的化合物则均有不同程度的毒性,特别是砷的无机化合物的毒性尤为强烈。近年来,砷的致癌作用更引起人们的注意。因此,砷化物在开采、冶炼和使用过程中对环境的污染及对人体的危害已成为环境保护的重 Arsenic rarely exists in nature in the free state, mostly in metal or sulfur compounds. Arsenic compounds are widely used in industrial and agricultural production sector. Free arsenic toxicity is weak, or even considered non-toxic, while the arsenic compounds have varying degrees of toxicity, especially inorganic arsenic toxicity is particularly strong. In recent years, the carcinogenic effect of arsenic has drawn more attention. Therefore, the arsenide in the mining, smelting and use of the process of environmental pollution and harm to the human body has become a heavy environmental protection