Because of similarity of chemical character,Zn and Cd give birth to accompany always,go to the plant by soil,then endanger the human health through the food chain.

• 由于化学性质相似,锌、镉在自然界总是伴生、伴存而造成伴随危害,经土壤到植物,继而通过食物链危害人类健康。