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Lead poisoning is far less common since paint containing lead pigment was banned (in 1978 in the United States) and lead was eliminated from automotive gasoline (in 1986 in the United States and by 2011 in all but 6 countries in the developing world). However, lead poisoning (plumbism) is still a major public health problem in cities on the East Coast of the United States.
Workers in industries that handle lead are at risk of lead poisoning, as are children who live in older houses that contain peeling lead paint or lead pipes. During home remodeling, people may be exposed to significant amounts of lead in the form of particles scraped or sanded off during surface preparation for repainting. Young children may eat enough paint chips, particularly during remodeling, to develop symptoms of lead poisoning. Some ceramic glazes contain lead. Ceramic ware, such as pitchers, cups, and plates, made using these glazes (common outside the United States) can leach lead, particularly when in contact with acidic substances (such as fruits, cola drinks, tomatoes, wine, and cider). Lead-contaminated moonshine whiskey and folk remedies are possible sources, as are occasional lead foreign objects in the stomach or tissues (such as bullets or curtain or fishing weights). Bullets lodged in certain soft tissues may increase levels of lead in the blood, but that process takes years to occur. Occupational exposure can occur during battery manufacture and recycling, bronzing, brass making, glass making, pipe cutting, soldering and welding, smelting, or working with pottery or pigments. Certain ethnic cosmetic products and imported herbal products and medicinal herbs contain lead and have caused cluster outbreaks of lead poisoning in immigrant communities. Fumes of leaded gasoline (in countries where it is still available) recreationally inhaled for the intoxicating effects on the brain may cause lead poisoning.
Lead affects many parts of the body, including the brain, nerves, kidneys, liver, blood, digestive tract, and sex organs. Children are particularly susceptible because lead causes the most damage in nervous systems that are still developing.
If the level of lead in the blood is high for days, symptoms of sudden brain damage (encephalopathy) usually develop. Lower blood levels that are sustained for longer periods of time sometimes cause long-term intellectual deficits.
Symptoms and Diagnosis
Many people with mild lead poisoning have no symptoms. Symptoms that do occur usually develop over several weeks or longer. Sometimes symptoms flare up periodically.
Typical symptoms of lead poisoning include personality changes, headaches, loss of sensation, weakness, a metallic taste in the mouth, uncoordinated walking, poor appetite, vomiting, constipation, crampy abdominal pain, bone or joint pains, high blood pressure, and anemia (see Anemia: Overview of Anemia). Kidney damage often develops without symptoms.
Young children may become cranky and their attention span and play activity may decrease over the course of several weeks. Encephalopathy can then begin suddenly and worsen over the next several days, resulting in persistent, forceful vomiting; poor coordination and difficulty walking; confusion; sleepiness; and, finally, seizures and coma. Chronic lead poisoning in children may cause intellectual disability, seizure disorders, aggressive behavior disorders, developmental regression, chronic abdominal pain, and anemia.
Adults who are exposed to lead at work typically develop symptoms (such as personality changes, headaches, abdominal pain, and damage to nerves) over several weeks or longer. Adults may develop loss of sex drive, infertility, and, in men, erectile dysfunction (impotence). Encephalopathy rarely develops in adults.
Children and adults may develop anemia. Children and adults who inhale the fumes from leaded gasoline may develop symptoms of psychosis in addition to typical symptoms of lead poisoning.
Some symptoms may diminish if exposure to lead is stopped, only to worsen again if exposure is resumed.
The diagnosis of lead poisoning is based on symptoms and a blood test. Adults whose jobs involve handling lead need frequent blood tests. Children living in communities with many older houses, where peeling lead-based paint is common, should also undergo blood tests for lead. In children, bone and abdominal x-rays often show evidence of lead poisoning.
Prevention
Commercially available kits should be used to test household paint (except in houses built after 1978), ceramics made outside the United States, and water supplies for lead content. Measures that reduce the risk of household poisoning include regular hand washing, regular washing of children's toys and pacifiers, and regular cleaning of household surfaces. Dusting affected windowsills weekly with a damp cloth removes some dust that could contain lead from paint. Chipped leaded paint should be repaired. Larger renovation projects to remove leaded paint can release large quantities of lead into the house and should be done professionally. Commercially available faucet filters can remove most lead from drinking water.
Adults exposed to lead dust at work should use appropriate personal protective equipment, change their clothing and shoes before going home, and shower before going to bed.
Treatment
Treatment consists of stopping exposure to lead and removing accumulated lead from the body. If an abdominal x-ray shows lead chips, a special solution of polyethylene glycol is given by mouth or through a stomach tube to wash the contents of the stomach and intestines (a process called whole-bowel irrigation).
Doctors remove lead from the body by giving drugs that bind with the lead (chelation therapy), allowing it to pass into the urine. All drugs that remove lead work slowly and can cause serious side effects.
People with mild lead poisoning are given succimer by mouth. People with more serious lead poisoning are treated in the hospital with injections of chelating drugs, such as dimercaprol, succimer, and edetate calcium disodium. Because chelating drugs also can remove beneficial minerals, such as zinc, copper, and iron, from the body, the person often is given supplements of these minerals.
Even after treatment, many children with encephalopathy develop some degree of permanent brain damage. Kidney damage is also sometimes permanent.
Last full review/revision February 2013 by Gerald F. O'Malley, DO; Rika O'Malley, MD
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