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Lead PoisoningTopic OverviewWhat is lead poisoning?Lead poisoning occurs when you absorb too much lead by breathing or swallowing a substance with lead in it, such as food, dust, paint, or water. Too much lead in the body can cause irreversible problems in growth and development in children, including:
In adults, lead poisoning can cause serious health problems, including high blood pressure and damage to the brain, nervous system, stomach, and kidneys. Although it is not normal to have lead in your body, a small amount is present in most people. Lead can damage almost every organ system, with the most harm caused to the brain, nervous system, kidneys, and blood. What causes lead poisoning?Lead poisoning is usually caused by months or years of exposure to small amounts of lead at home, work, or day care. It can also happen very quickly with exposure to high concentrations. The most common source of lead exposure for children is lead-based paint and dust and soil that are contaminated by it, especially in older homes and buildings. About one-quarter of all U.S. dwellings have lead paint hazards such as these.1 Toys and jewelry made in other countries can sometimes contain high lead levels. For a list of recalled products, see the Consumer Product Safety Commission Web site at www.cpsc.gov. Adults are most often exposed to lead in the workplace or while doing hobbies. Those who work with lead—such as metal smelters, welders, or pottery makers—are at a higher risk of lead poisoning. Other sources of lead exposure include:
Most people are exposed to some amount of lead in their lifetime. Although environmental regulations have reduced lead exposure in the United States, it is still a significant health risk, especially for young children. It is estimated that lead poisoning affects about 310,000 children in the U.S.2 What are the symptoms?There may be no noticeable symptoms of lead poisoning because the effects are subtle or may mimic other conditions. When lead poisoning levels are severe, some general symptoms can include digestive problems, fatigue, and headaches. Children with chronic lead poisoning may show slightly lower intelligence and may be smaller in size than children their age who do not have lead poisoning. Behavioral problems can include irritability or aggressiveness, hyperactivity, learning difficulties, lethargy, and loss of appetite. In adults, behavioral symptoms can include irritability, mood and personality changes, changes in sleep patterns, difficulty concentrating, and memory loss. At high levels, lead can affect the central nervous system, leading to poor coordination, weakness in hands and feet, headaches, and in severe cases, convulsions, paralysis, and coma. How is lead poisoning diagnosed?A lead blood test measures the amount of lead in the blood. Although this test does not measure the complete level of lead in the body, it is usually the first test done. A urine sample collected over 24 hours and tested for lead can give information about the total lead in the body (body lead burden) and is often used before treatment to remove lead (chelation therapy) is started. Diagnosing lead poisoning is difficult because the symptoms can be caused by many diseases. Most children with lead poisoning do not have symptoms until their blood lead levels are very high. How is it treated?Treatment for lead poisoning includes removing the source of lead exposure and eating a balanced diet. Adequate nutrition, especially sufficient iron intake, helps prevent absorption of lead. Often this treatment approach is enough to reduce lead levels in the body. If this is not successful or if lead levels are very high, chelation therapy may be used. Chelation therapy involves taking medicines that bind to lead in the body and help speed its elimination through the kidneys. It is important to make sure that children are not exposed to lead. The most effective means of prevention is to keep children out of buildings that contain lead-based paint until the lead has been either removed or sealed away and the environment is certified by professionals to be free of lead residues. Who is at highest risk of lead poisoning?Lead poisoning can occur at any age, but children are most vulnerable to contamination. Children who are at highest risk for lead poisoning include those who:
Also, lead exposure or lead poisoning may occur in:
Frequently Asked Questions
CauseLead poisoning is caused by swallowing or breathing lead-contaminated substances or by skin contact. Small children may get lead poisoning by licking, chewing, or eating lead paint on toys, jewelry, or woodwork such as windowsills. In 2007, the U.S. Consumer Product Safety Commission (CPSC) found high lead content in many children’s toys and jewelry made in other countries. For a complete list of recalled products, see the CPSC Web site at www.cpsc.gov. Small children also may be exposed by breathing, swallowing, or playing in lead-contaminated dust, soil, or smoke. Although lead poisoning can sometimes result from a single large dose of lead, it usually is caused by months or years of exposure. Because lead cannot be seen, tasted, or smelled, people usually do not know when they are being exposed. Nearly everyone has some lead in his or her body. Before its harmful effects were realized, lead was used in most gasolines, paints, water pipes, food and drink cans, and many other products. For example, house paint made before 1950 often contained as much as 50% lead. Paint manufactured up until 1978 still contained lead. About one-quarter of all U.S. dwellings have lead paint hazards (such as very small pieces of old paint, or dust or soil that contains lead).1 Environmental regulations have reduced sources of lead pollution, significantly reducing lead in paint, gasoline, plumbing systems, and food and drink cans. For example, in 1988 the Environmental Protection Agency (EPA) banned the use of lead solder and other leaded parts to connect plumbing to public water supplies. But lead does not break down, so any lead already present in soil or water will stay there unless it is physically removed. Common sources of lead poisoning are:4
A pregnant woman who is exposed to lead can pass it to her unborn baby.5 Lead can also be passed to a baby through the mother's breast milk. A study focusing on children in an urban primary care clinic showed that iron-deficient children absorb greater amounts of lead than children with adequate iron intake. Though further study is needed, the results suggest that ensuring iron intake in high-risk populations may help decrease the amount of lead absorbed by children in these groups.6 SymptomsLead poisoning
usually does not cause symptoms until the level of lead in your blood is very
high. Most lead poisoning comes from low levels of exposure over a long period
of time. The major organ systems affected are the
central nervous system Chronic lead exposure may cause the following symptoms. General physical symptoms in children and adults (usually seen when lead poisoning levels are severe)
Children with chronic low blood lead levels who may not have obvious symptoms of lead poisoning may have learning problems and be smaller in size than children their age who do not have low to moderate levels of lead poisoning. Studies have shown that declines in IQ can even be seen in children with blood lead concentrations below 10 micrograms of lead per deciliter of blood (10 mcg/dL), the level of concern defined by the U.S. Centers for Disease Control and Prevention and the World Health Organization.7, 8 Chronic exposure to lead may also cause behavioral problems in these children. Behavioral symptoms in children
Behavioral symptoms in adults
Neurological symptoms (caused by effects of lead on the nervous system)
Diagnosing lead poisoning can be difficult because many other conditions cause similar symptoms. Severe symptoms of acute lead poisoning can include seizures, unconsciousness, paralysis, or swelling in the brain. But exposure to such a high level of lead is not common. If you experience these symptoms, seek emergency medical care. What HappensPeople are exposed to lead if they swallow or breathe lead-contaminated substances. Lead poisoning can be caused by a single large dose of lead, although it is usually the result of exposure to small amounts of lead over a long period of time. Lead is slowly eliminated from the body in urine, bowel movements, and, to a very small extent, sweat. When the body is exposed to more lead than it can get rid of, it stores the extra lead in the blood, organs, bones, and teeth, and lead poisoning results. Lead can damage the kidneys, central nervous system (brain and spinal cord), and reproductive system. And it can cause high blood pressure. Lead is especially harmful to a child's developing brain. Blood lead levels are measured in micrograms per deciliter (mcg/dL). There are different opinions among scientists and doctors on what is a safe level of lead in the blood. Lead has no known function in the body—its natural level in people before the industrial revolution in the 1800s and early 1900s was near zero. Health effects of high blood lead levels in childrenChildren are more easily and significantly affected by high blood lead levels than adults. High levels of lead in the blood are caused by lead poisoning. There are five classes of lead poisoning, according to the United States Centers for Disease Control and Prevention (CDC). These levels range from class 1 (less than 10 mcg/dL) to class 5 (a medical emergency of at least 70 mcg/dL).
Children who were exposed to lead before birth may be underweight and have low intelligence, attention-span problems, and other signs of nervous system damage. A recent study showed that declines in IQ can be seen in children with blood lead concentrations below 10 mcg/dL, the level of concern defined by the U.S. Centers for Disease Control and Prevention and the World Health Organization.7 Health effects of high blood lead levels in adultsHigh blood lead levels affect adults in several ways.9
Unfortunately, people may not have noticeable symptoms until blood lead levels are high enough to cause serious damage to body systems. What Increases Your RiskChildrenAge and environment determine a child's risk for lead poisoning. Young children who live in housing built before 1978 (before lead paint was banned) are at risk. Lead paint was used even more in housing built before 1950.10 Recent or ongoing house renovation can increase the risk of lead exposure if lead paint is being removed. Very young children are more likely to ingest lead by touching or playing in lead-contaminated soil or dust and then putting their hands in their mouths. They may also chew on or lick toys, jewelry, or woodwork (such as windowsills) painted with lead-based paint. In 2007, the U.S. Consumer Product Safety Commission (CPSC) found high lead content in many children’s toys and jewelry made in other countries. For a complete list of recalled products, see the CPSC Web site at www.cpsc.gov. Children who come from low-income families are more likely to have high levels of lead in the blood because they are more likely to be exposed to lead-contaminated soil and dust or deteriorated paint in older housing. Children who are immigrants, refugees, or adoptees from other countries may also be more likely to get lead poisoning.3 Babies, toddlers, and young children up to 6 years old are more likely to have problems from lead poisoning because of their:
Inadequate iron intake is being studied for links to increased absorption of lead. It's possible that increasing iron intake in children at high risk for lead poisoning may slow the absorption of lead.10 AdultsThe risk of lead poisoning for adults depends mostly on whether they have jobs or hobbies that involve exposure to lead. It may not always be obvious when there is lead in the workplace. For example, people who work in construction or do remodeling may inhale lead while scraping or sanding wood that has lead-based paint on it. People who work with lead can bring it home on their clothes, shoes, and hair, and expose others in the house. Adults may also be exposed to lead from cups or dishes with ceramic glazes or from natural or traditional remedies or supplements that contain lead. Some cosmetics manufactured outside of the United States also contain lead. The risk of lead poisoning increases if you drink homemade liquor made in stills built with lead solder, especially "moonshine whiskey" made in the southern U.S.4 When To Call a DoctorCall your doctor if you know or suspect that you or someone in your family has lead poisoning, has been exposed to lead, or has ingested a large dose of lead (for example, if your child eats any lead-contaminated paint chips). Call 911 or other emergency services immediatelyif someone has convulsions or is unresponsive. Call your doctor if you or someone else has either severe abdominal pain or frequent forceful, explosive vomiting usually not preceded by nausea (projectile vomiting). Call your doctor if you live in an older home with peeling or chipping paint and someone in the house has any of the following symptoms:
Call your doctor for advice if someone in your home has a job or hobby that involves the use of lead. Chronic (long-lasting) lead poisoning often has no symptoms at all. See the Early Detection portion of the Exams and Tests section of this topic for guidelines on when to test someone for lead poisoning. Watchful WaitingWatchful waiting is not appropriate if you think that someone has lead poisoning. Call your doctor. Who To SeeScreening for lead poisoning is usually done by your regular family doctor. The following health professionals can order tests for blood lead levels:
Treatment for lead poisoning might be done by any of the health professionals above, by a doctor who specializes in the treatment of poisoning (toxicologist), or by a specialist in environmental and occupational medicine. To prepare for your appointment, see the topic Making the Most of Your Appointment. Exams and TestsDiagnosing lead poisoning can be difficult, especially because its symptoms are so general. A blood lead test can detect the amount of lead in the blood. If your doctor suspects lead poisoning, he or she will take at least two blood tests to confirm it. This test does not measure the complete level of lead in the body, but it is usually the first test done. Results need to be reported to the local health department if 2 or more blood lead levels are above 10 micrograms per deciliter (mcg/dL). A home inspection is needed to find the source of the lead contamination. Other tests that can be helpful if lead poisoning is suspected include:
Early DetectionScreening programs for lead poisoning check large numbers of children or adults who are likely to be exposed to lead. These programs are set up by the U.S. Centers for Disease Control and Prevention (CDC) and give local and state agencies information to help find which areas are the most likely to have high lead levels. Age of housing is an important factor in determining risk because older homes tend to have lead-based paint. If lead exposure is likely, then blood tests for infants and young children will be recommended to measure blood lead levels. Talk to your child's doctor about whether your child is at risk. During a routine health exam, the risk for lead exposure can be evaluated by answering questions about family members' living and working conditions. The doctor may then decide whether blood lead levels should be measured. ChildrenChildren should be tested, no matter what their age, if they have been exposed to lead or if they have symptoms that could be caused by lead poisoning. Screening tests done on 1- to 2-year-olds have shown lead in the environment in most places. When children in an area no longer test positive for traces of lead, routine screening of those children is no longer needed. Screening programs in an area would need to be restarted only if something changed that would increase the risk for lead in that area. The U.S. Preventive Services Task Force (USPSTF) does not recommend:11
State and local health departments can provide information on screening recommendations in your area. In addition, an individual child's risk for lead poisoning can be determined by answering a few screening questions. AdultsThe U.S. Occupational Health and Safety Administration (OSHA) requires companies to test the blood of employees who work with lead. OSHA sets industry standards to protect workers. For more information, see the Other Places to Get Help section of this topic. Adults who do not work with lead usually are not tested for lead poisoning. If you are pregnant or trying to become pregnant and you or a family member works with lead, you may want to ask your doctor about your risk for lead poisoning. The USPSTF does not recommend routine testing of blood lead levels in pregnant women who don't have symptoms.11 Treatment OverviewTreatment for lead poisoning begins with removing the sources of lead and providing balanced nutrition. These measures are usually sufficient to limit exposure to lead and reduce lead levels in the body. Old paint chips and dirt are the most common sources of lead in the home. Lead-based paint and the dust and dirt that come from its decomposition should be removed by professionals. In the workplace, removal of sources usually involves removing lead dust that is in the air and making sure adults don't bring contaminated dust or dirt into the home on clothes worn for work. Balanced nutrition includes adequate amounts of vitamins and minerals such as iron, calcium, and vitamin C. A person who eats a balanced, nutritious diet absorbs less lead than a person whose diet is inadequate. If removing the source of lead and balancing nutrition do not reduce lead levels, or if the blood lead level is very high, chelation therapy may be used. Chelation therapy is a process that lowers the amount of lead stored in the body. Drugs called chelating agents cause metals like lead to bind to them, and then they are eliminated from the body through urine. Because chelating agents increase the absorption of lead and other metals, it is essential that sources of lead exposure be removed before a person is treated. If blood lead levels do not come down with treatment, the home and work areas need to be rechecked for other sources of lead. Contact your local health department to see what inspection services are available in your area. Prevention, primarily through screening of both children and adults, is the most effective means of reducing or eliminating the effects of lead poisoning. Damage from lead poisoning, especially to the central nervous system, is often incurable and may not improve with treatment. PreventionLead poisoning may be prevented or limited by removing the source of lead in your home or workplace and by eating a healthful, balanced diet. The most common sources of lead are lead-based paint and lead in dust or soil. Peeling or chipped paint is easily crushed into dust in the home or into the soil around the house. Older, industrial buildings may have been painted with lead-based paint. When these buildings are remodeled, dust containing dangerous levels of lead can contaminate the air and soil. Houses built before 1978 probably have some amount of lead-based paint, and homes built prior to 1950 often have the highest level of lead-based paint. Lead paint can be found on some toys, too. In 2007, the U.S. Consumer Product Safety Commission (CPSC) found high lead content in many children’s toys and jewelry made in other countries. For a complete list of recalled products, see the CPSC Web site at www.cpsc.gov. Levels of lead in the blood can be reduced through regular housecleaning by crews trained to reduce leaded dust on surfaces. Cleaning includes wet-mopping floors, damp sponging of walls and counters, and vacuuming with a high-efficiency vacuum. You can ask your local or state health department to test your home for lead paint or to give you the names of companies that can do such tests. Home test kits may not be accurate. Other sources of lead include:
Certain measures can prevent or reduce exposure to lead. If you have lead in your house paint, soil, or drinking water, you may want to consider the following:
Balanced nutrition may prevent or reduce lead poisoning. Vitamin C, iron, zinc, calcium, and phosphorus make it less likely for the body to absorb lead.4 So getting enough of these nutrients day-to-day may help. Frequent meals or snacks help prevent lead poisoning, because lead is not as easily absorbed on a full stomach. Also, people who eat high-fat diets absorb more lead, as do people with iron deficiency. Home TreatmentIf you suspect that someone in your family has lead poisoning, consult a doctor right away. The most important thing you can do is remove sources of lead in and around your home. If you have lead in your house paint, soil, or drinking water, you may want to consider the following:
Good nutrition is important. Make sure your family eats a diet that includes adequate amounts of vitamins and minerals such as iron, calcium, and vitamin C. MedicationsChelating agents are used for severe lead poisoning. Chelating agents are medicines that bind with lead in blood and both soft and bony tissues and eliminate it quickly from the body, usually through the urine. The use of chelating agents for lead poisoning is still being studied, and there is no single treatment or drug of choice. In general, drug treatment is recommended when blood lead levels are above 45 micrograms per deciliter (mcg/dL) or when there are symptoms of lead poisoning, especially lead encephalopathy. Chelation therapy is not recommended for all children with blood lead levels of 20 mcg/dL through 44 mcg/dL.10 Reducing or removing environmental lead sources, correcting iron deficiency, and improving nutrition may be enough to lower lead levels in the blood. The decision to use chelating agents depends on how long a child has been exposed to lead, the child’s blood lead level, and his or her symptoms. It also depends on whether the blood lead level stays high after the child eats a more balanced diet and after the source of lead is removed or reduced. In theory, chelating agents prevent further damage by reducing blood lead levels. Damage to the blood may repair itself if blood lead levels are lowered. Kidney damage may also heal, unless it has been too extensive. Chelation therapy may not reverse central nervous system (brain and spinal cord) damage that has already occurred. Medication ChoicesChelating agents are chemicals that bind with lead for the treatment of lead poisoning. What To Think AboutChelating agents increase absorption of lead and other metals. A person exposed to lead while taking a chelating agent may absorb more of the lead, thus defeating the purpose of the therapy and possibly doing even more harm. Therefore, it is essential that lead sources be removed from your environment before treatment. (This may require that treatment be administered in a hospital.) Do not return home or to the workplace until lead sources have been removed. Results need to be reported to the local health department if 2 or more blood lead levels are above 10 mcg/dL. A home inspection is needed to find the source of the lead contamination. If blood lead levels do not come down with treatment, your home and work areas need to be rechecked for other sources of lead. Contact your local health department to see what inspection services are available in your area. Iron deficiency also increases lead absorption. Iron deficiency cannot be treated at the same time as chelation therapy because the chelating drug will bind to iron and remove it as well. Iron deficiency must be treated either before or after chelation therapy. Chelation therapy does reduce blood lead levels and may slow down problems with kidney function associated with lead poisoning. But it does not appear to improve cognitive damage or other neurological problems already caused by the lead poisoning.12 If chelation therapy is necessary, it is best to consult with a doctor experienced with this treatment. SurgeryThere is no surgical treatment for lead poisoning. Other TreatmentThere are no other treatments for lead poisoning. Other Places To Get HelpOrganizations
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