In the past, lead poisoning was thought to arise from pica (abnormal ingestion) among children living in old, broken-down houses with peeling layers of lead- based paints. In the past two decades, lead intoxication has occurred with decreasing frequency. This may in part be related to less use of lead in paint and leaded gasoline; several studies relate environmental lead contamination to traffic density patterns. In the United States, hundreds of occupations involve potentially significant exposure. It is estimated that more than 800,000 American workers have potentially significant lead exposure. Lead and other metal workers or miners, storage battery workers, and pottery makers are particularly heavily exposed. Workers in auto manufacturing, ship building, paint manufacture and printing industries are also at substantial risk, as are house painters and those who repair old houses. In past centuries lead was added to wine to sweeten it, a deception that was eventually made punishable by death. Recently, adding lead to various herbal and folk medicines has resulted in poisoning. Bullets left in the body can result in lead poisoning, especially if a joint is involved, because synovial fluid appears to be a good solvent for lead. The interval between the bullet getting embedded in the body and clinical evidence of lead poisoning has ranged from 2 days to 40 years.