Lead poisoning develops when people ingest or inhale lead, usually over a long period of time. Although people of all ages are susceptible to the problem, children are especially vulnerable to its long-term effects, particularly if they ingest lead during the first two years of life when the nervous system is still developing. Children also absorb more of the lead they ingest than adults, a factor that compounds their risk of building up toxic levels of lead.
HOW DOES LEAD POISONING OCCUR?
The main cause of lead poisoning in children is ingestion of contaminated paint chips and dust in old homes and apartments. It is estimated that as many as 60 percent of buildings in older cities such as New York, Philadelphia and Boston may have lead paint on their inside walls. In crowded metropolitan areas, lead-containing car and truck emissions may also contribute to lead poisoning.
A fetus can develop lead poisoning if the mother was exposed to high levels of lead during pregnancy. In addition, some evidence indicates that women who were exposed to high levels of lead during their own childhoods can pass lead to their infants in breast milk.
Parents who work in environments with high lead levels may inadvertently expose their children to lead dust on their clothes and hair. Children living in homes near factories with lead-containing emissions also may be at risk.
Pottery glazes used to contain lead. The use of such materials is now illegal in the United
States, but occasional cases of acute lead toxicity are reminders that antique, imported and improperly produced eating vessels are a potential source of lead.
WHAT HAPPENS WHEN A CHILD HAS LEAD POISONING?
Inhaled or ingested lead tends to build up in the body, particularly in the bones but also in other body tissues. As toxic levels of lead build up, a number of subtle abnormalities become evident.
The U.S. Centers for Disease Control and Prevention consider any lead level over ten as elevated and will require monitoring. As lead levels rise, the number of symptoms may increase. Youngsters in the 25 to 40 range may exhibit attention problems and hyperactivity. At levels above 45, they may show poor appetite and insufficient weight gain. Children with lead levels above 80 micrograms per deciliter of blood may suffer brain damage, persistent vomiting and convulsions. Prolonged exposure to even relatively modest elevations of lead is correlated with the loss of IQ points.
HOW CAN THE PEDIATRICIAN TELL IF MY CHILD HAS LEAD POISONING?
The pediatrician may notice subtle signs of chronic lead poisoning such as delayed development, poor coordination and behavior disturbances. The diagnosis is made by measuring levels of lead in the blood. In areas where the risk is high, all children between ages one and five years may be periodically tested for lead poisoning.
WHAT TREATMENTS ARE AVAILABLE?
First and foremost, the source of the lead must be identified and removed from the child's environment. The use of TSP soap can diminish the hazard from dust contaminated with lead, but more drastic measures such as deleading are called for when there is significant exposure.
Children with low levels of lead poisoning (20 to 30) are often managed with nutritional supplementation, specifically iron supplements and foods rich in calcium and zinc. Children with higher levels (over 40 to 45) need to undergo chelation therapy, in which a drug that binds to lead is given orally, intramuscularly or intravenously, depending on the lead level. Once the chelating agent picks up the lead, it can be excreted. In severe cases several chelation treatments may be needed to remove the lead.
WHAT ARE THE LONG-TERM EFFECTS?
If high levels of lead are detected early enough, the child should recover completely. There is some evidence, however, that subtle neurological symptoms such as reduction in IQ may not be fully reversible.
PREVENTING LEAD POISONING
• If you live in an apartment or house that was built before World War II, use a home test or get a professional company to determine if there is lead paint in your home. If there is, it should be replaced (by removing the painted woodwork and replacing it with new), sealed off with a latex sealer, or removed (using special chemicals and safety gear). For more information on lead paint and old houses, send for the booklet "What You Should Know about Lead-Based Paint in Your Home," from the Consumer Product Safety Commission, Washington D.C. 20207. (To expedite, write "Publication Request" on the envelope.)
• Remove all flaking or peeling paint from the areas where your child plays. Hallways, windows and doors are most apt to be in bad repair because of the increased traffic in these areas.
• Use a high-power vacuum to free carpeting and floors from lead and other dust.
• Your young child should NOT be in the house during the de-leading process. This is a good time to visit friends or grandmother for a few days.
• If possible, use air conditioning instead of opening windows if you live near a highway or factory.
• Choose ceramic dinnerware and glassware made in the United States and certified lead-free by the manufacturer.
• Check with your local water authority and find out the level of lead in your drinking water. If the plumbing in your building is old, have an inspector determine the lead level of the water coming out of the faucet. If it is too high, switch to bottled water.
