Lead is a bluish or silver-gray soft metal. Two of its most important forms in terms of air pollution are tetraethyl lead and tetra methyl lead. These two forms of lead are used as "anti-knock" additives in petrol.
Sources of Lead:
Lead particles are emitted into the atmosphere through the exhaust of vehicles that use leaded petrol. Other sources of lead include: used car batteries; production of metals like lead, copper, nickel, zinc, cadmium, iron, and steel; thermal power plants and other coal combustion plants; mining; cement production; refuse incineration; wood combustion; and lead-based paints.
Human Health Effects of Lead:
Environmental Effects of Lead:
Exposure to lead causes liver and kidney damage, gastro-intestinal damage, slower mental development in children, and abnormalities in fertility and pregnancy. Children are the most vulnerable to lead poisoning, which can cause behavioural problems, lower IQs, and decreased ability to concentrate.
Lead is generally toxic to both plants and animals.