ABSTRACT
Arsenic (As) in natural world mainly comes from sedentary product of parent rocks or parent soil materials. The average content of arsenic in the lithosphere is about 1.8 mg/kg; the content of that in natural soil is ∼0.2-40 mg/kg, the average concentration in sea water is 3 μg/L, and the total content of arsenic in the ocean is 4.3 × 1012 kg. Arsenic content in volcanic eruptions is 20 mg/kg; and arsenic in the atmosphere is mainly from release of soils and plants, and the content of arsenic which overflows from the land surface to the atmosphere is about 2.37 × 107 kg.
