Abstract
Lead (Pb), which is widely used in industry, is a common element found in low concentrationsin the Earth's crust. Lead has been used since prehistoric times.
As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. This environmental contaminant causing irreversible health effects mainly in children.
Especially children under the age of six are most at risk for lead poisoning. Lead toxicity causes hematological, gastrointestinal, and neurological dysfunction.
Symptoms are usually noted with blood lead greater than 2 μmol/litre. Severe or prolonged exposure may also cause chronic nephropathy, hypertension, and reproductive impairment.
Lead inhibits some enzymes, alters cellular calcium metabolism, stimulates synthesis of binding proteins in kidney, brain, and bone, and slows down nerve conduction. The emission sources and pathological effects of lead are discussed.