Lead Poisoning Health Article

Lead Poisoning

A toxic condition that results from the ingestion of lead, typically occurring in young children.

Lead poisoning occurs when small amounts of lead, usually in the air or dust, are ingested over a period of time. Its victims are chiefly young children who chew on furniture and woodwork painted with lead-based paints or who eat dust and soil that has been contaminated. Ten percent of the ingested lead is absorbed by the body; children with iron deficiencies can absorb as much as 50%. High lead levels in the body decrease the production of heme, the iron compound in the blood, resulting in anemia. Unchecked, the anemia prevents the normal rate of brain and cell activity resulting in stunted physical growth, learning disabilities and behavioral problems. Recent studies suggest that lead poisoning is a factor in juvenile delinquency as well. Abnormally high lead levels also cause the loss of large amounts of amino acids, carbohydrates, and salts through the urine, resulting in kidney failure. In the most severe cases, the brain swells (lead encephalopathy), followed by seizures and death.

Early symptoms of lead poisoning include fatigue, paleness, constipation, loss of appetite, irritability, anemia, sudden behavioral changes, loss of short-term memory, slowing of mental development, and sleep disorders. In the final stages before the onset of lead encephalopathy, victims experience vomiting, abdominal pain (lead colic), headaches, clumsiness, and muscle weakness.

In the 1970s, lead-based paints and leaded gasoline were banned in the United States. However, lead particles from gasoline are still found in soil and many older inner-city dwellings have not been stripped of their leaded paint. Drinking water in older homes may also be passing through old lead-containing pipes. Experts estimate that three million preschool children in the United States have elevated levels of lead. The highest incidence, 36%, occurs among low-income African American children living in industrialized cities. Seventeen percent of Hispanic American children have elevated levels. The figure is only 4% for white, non-city-dwelling children. The high figures for inner-city children is exacerbated by the fact that many also suffer from iron-deficiency. In mid-1996, the Centers for Disease Control (CDC) detected unhealthy levels of lead in imported metal miniblinds, putting middle-class children at risk as well. According to the CDC, exposure to sunlight causes the lead used as a binding agent on the blinds to break down and mingle with the dust on the slats. Tests are now being conducted on other imported plastic and metal merchandise such as patio furniture and playground equipment.

The CDC recommends that all children under the age of six be tested annually. Many school systems have instituted this testing as part of their health screening. Parents who suspect that their children have ingested lead particles should have them tested immediately. Severe cases are treated with chelation therapy that binds the lead to tiny particles that are then filtered out of the bloodstream by the kidneys and eliminated in the urine. Because the effects of lead poisoning develop gradually over time, every child who tests positive for lead poisoning should undergo neuropsychological testing by the age of five and have his or her progress monitored throughout childhood and adolescence.

When a diagnosis is positive, the lead in the building where the poisoning occurred must be safely eliminated before the child returns. Children should not be present in the building during this procedure. Strip the walls and/or woodwork with liquid paint remover, covering the floor with drop cloths to catch the paint chips and dust. The surfaces should then be patched, sealed and repainted with lead-free paint or covered with wallpaper or paneling. Dispose of the drop cloths and wash the floors. Furniture and toys painted with leaded paint should be discarded or stripped and repainted in the same fashion.

Parents and child-care providers should also take care not to use lead or pewter cooking utensils, leadglazed pottery or lead-lined storage containers.