Lead is a metal found in the environment. If a person is exposed to lead even in relatively small amounts, poisoning may occur.
Lead is not natural within the body and is not required in the diet. Because of technology, however, lead exposure became increasingly common throughout the mid-20th century. Since the 1970s, lead has been removed from gasoline, from paint, and from other sources that can contaminate the environment.
However, sources such as discarded car batteries and paint in old houses still exist, and cause more damage to the body than people formerly realized. In addition, workers in various industries continue to be exposed to lead in the course of their jobs. Any of these exposures can lead to increased levels of lead in the body, cause harm in several ways.
The symptoms of lead poisoning can vary widely. The effects of lead poisoning depend on the person's age, the amount of lead in the body, and how long the exposure has been going on.
Lead poisoning is called acute if the exposure happens quickly. Chronic exposure occurs over weeks or months. Both types of poisoning are harmful, but the symptoms are somewhat different.
Acute or sudden poisoning may cause: sudden changes in behaviorabdominal distressnausea and vomitingunsteady gait or walking style, known as ataxiaseizures, impaired consciousness, or even coma
Chronic or slow poisoning may cause: gradual changes in behavior, such as a child becoming hyperactive who was not that way beforedecreased school performanceintelligence problems and memory loss occasional abdominal distress paralysis of the hands or feet, which usually only occurs in adultsfatigue joint pain anemia, or low red blood cell countskidney damagea bluish-black line at the area where the teeth and gums meet
A person can be exposed to lead from the following sources: leaded gasolinecar exhaustpaint made before 1978industrial lead exposureburning batteriespoorly glazed ceramic objects, which may be used to store beverages
The people most commonly affected by lead poisoning are children. Children who live in old buildings with lead paint that is peeling or dissolving are at high risk. Lead dust or paint chips from lead paints may be breathed into the lungs or eaten.
Though quite rare today, severe lead poisoning can cause death. Other risks are the long-term damage lead poisoning may cause in the brain, nerves, and kidneys.
The government has done the following to prevent lead poisoning: mandated use of unleaded gasolinemandated better car emission standardsbanned lead paint
Two measures have drastically reduced the number of cases of lead poisoning: Avoiding exposure to lead is the most important prevention. People living in older buildings with peeling lead paint need to have their home or apartment repaired. People working in manufacturing should ask about possible lead exposure and follow published standards for the protection of workers. Batteries should not be burned.Testing to screen for lead poisoning is is second most important measure. Public health experts recommend a blood test to screen for lead poisoning in children living in environments where lead sources are likely to be found. A healthcare professional can determine whether testing is needed for an individual child. Testing is normally started between 6 and 12 months of age.
A careful history and physical exam may make a healthcare professional suspect lead poisoning. A blood test confirms the diagnosis by detecting the level of lead in the blood.
The most common long-term effect of lead poisoning is mild brain damage. This damage may be permanent and generally affects children, whose brains are still developing. Behavior problems, emotional problems, and lowered intelligence may all occur.
Kidney damage, nerve damage that may cause paralysis, and even death may also occur.
Lead poisoning is not contagious and poses no risks to others.
The most important treatment is stopping the source of lead exposure. For more severe poisoning, medications may be needed to help remove lead from the body. Chelation is a procedure that helps bind the lead and remove it from the body. Life-threatening lead poisoning, which is rare, requires treatment in a hospital.
Stopping lead exposure may involve major life changes and expense. For example, changing jobs, moving, or repairing the home or apartment may be needed.
All medications have side effects. The medications used to decrease lead in the body may cause allergic reactions and stomach upset. Other side effects depend on the specific medication used.
If caught early and treated correctly, lead poisoning may require no further treatment. Continued monitoring is advised in all cases, however. If caught late or not treated, the lead poisoning may cause permanent body damage. This may require ongoing treatment, such as psychiatric care.
Repeat blood tests are used to follow the lead level until it is normal. Other monitoring depends on whether the body has been harmed in some way.
Harrison's Principles of Internal Medicine, 1998, Fauci et al.
Nelson Texbook of Pediatrics, 1996, Behrman et al.