3.Radioactive Pollution:

          Some Radiation come from outer space, while other are emitted from radio-active rocks present in the earth. Man is adapted to such radiations.

        Radioactive pollutants which we must get rid of are those which result from nuclear explosions or nuclear tests. These radioactive pollutants accumulate and move from there sources to far way places by our currents. They fall with rain water, causing the death of living organisms, if they reach a high enough concentration. This radioactivity may accumulate in cells causing various carcinogenic diseases or congenital deformities for successive generations. This effect is still noticed in people who survived in Hiroshima and Nagasaki in Japan, after the dropping of atomic bombs at the end of the Second World War. We shall not forget what happened in Chirnopel (USSR) in 1986 which caused radioactive pollution in very distant places.

        Therefore, great efforts must be made to get rid of radioactive remains. This is done by storing them (since they can't be burnt) in thick steel containers mixed with cement. These containers are then buried at a great depth (200-300 meters) under the ground or the bottom of the ocean .