Many rivers and lakes around the world are polluted. The discharge of waste materials by factories and households causes pollution to rivers and lakes. The Rhine River in Europe and the Great Lakes in North America are good examples of a river and lakes that are polluted. Their water cannot be drunk.The same thing is happening to the sea. In one instance, certain factories in Japan dumped industrial waste into the sea. Many people suffered from lead or mercury poisoning after eating fish caught in such polluted waters. Pollution in certain areas of the sea is now reaching dangerous levels. Many ships discharge their waste materials and unwanted engine oil into the sea. These wastes contain lead and mercury which are poisonous. Sometimes, accidents to oil tankers can cause oil to be discharged into the sea and onto the beach.
đang được dịch, vui lòng đợi..
