Lead has accumulative and metabolic toxicity. In natural bodies of water, lead exists in different forms. Lead compounds are generally hard to dissolve and are easily adsorbed and deposited. They mainly comes from improper wastewater discharge and storage of batteries by the manufacturing industry. High lead concentrations serverely pollute the water. Granular lead pollutants from the combustion of lead compounds in petroleum also pollute the air. The pollutants finally drop to the ground or are brought into water bodies by rain, increasing the lead content of water.