英语阅读选题作业.ppt

1、,Heavy Metal Pollution,Contents,Add Your Text in here,Main Features,Classification and damage,Treatments and outlook,Fundamental Definition,Contents,Introduction,Pb-lead -铅 Cd-cadmium-镉 Cu-copper-铜 Hg-mercury-汞 Zn-zinc-锌 Cr-chromium-铬,Fundamental Definition,the proportion of heavy metal is bigger th

2、an 5，such as Lead（Pb）, cadmium（Cd）, mercury（Hg）and so on,Heavy metal pollution is one of the main pollutions of the environment which is caused by heavy metals and heavy metal compounds,What is the heavy metal？,heavy metal pollution,irreversible,enrichment,danger,It is hard to degradation in the env

3、ironment,The harm of human body is great,it is useless to treat from polluted soil,Main Features,air pollution,soil pollution,water pollution,.,Classification,There are three main field of pollution caused by heavy metal:,air pollution,Statistics released by WHO shows that more than 2 million people

4、 dead of the air pollution each year around the world . I think all of us cant forget the “ Vultures death ” caused by the Los Angeles smog occurred in the 1940s in America.,water pollution,Some companies discharge the wastewater containing heavy metal to the river ,this is a waring sign or conseque

5、nce of some underlying effects . Some fishes lived in water will absorb those , then people who eat those food will poisoning,The incident happened in Japan， people ate polluted fishes cause of Minamata disease,soil pollution,If person cultivate crops on those ground ,those metal will be absorbed by

6、 crops .Those crops always be used for food ,so when people eat those more or less heavy metal accumulating in their body.,cadmium（Cd） rice event,a survey showed 44% rice which content heavy metal in guangzhou Such as Itai-itai disease is consequence of Cadmium poisoning,soil pollution,If,some Brand

7、s contain heavy metals,Treatments and outlook,In view of the huge damages caused by heavy metal pollution. we are supposed to appeal to people to drive private car as little as possible,One is the microbial or physical adsorption, another is chemical degradation , and also phytoremediation is a better method to impro