Abstract
The amount of cadmium (Cd) discarded by nonferrous mining and smelting, which have been pointed out as two of the main sources of Cd in the environment, was estimated using statistics on zinc production and the Cd-to-zinc (Cd/Zn) ratio in ore. The sums of Cd discarded by mining and smelting from 1915 to 1999 were estimated to be 3, 300 t and 28, 000 t, respectively. The amount of Cd discarded by mining was estimated to be larger before World War II (peaking in the 1930s) than after. On the other hand, the amount of Cd discarded by smelting was calculated to have peaked in the 1970s. We also discussed that to what extent the discarded Cd could be transported in the environment.
