Lead Screening Recommendations Reviewed
A recent review of several studies by the U.S. Preventive Services Task Force (USPSTF), an independent group of national experts, concluded that there is not enough evidence to determine whether the benefits of screening people without symptoms for elevated lead levels outweigh any harms. Although the Task Force says there is not enough evidence to make a solid recommendation, several major health organizations do recommend screening asymptomatic patients to see if they may be at risk of lead exposure. For example:
- The American Academy of Pediatrics recommends a risk assessment periodically throughout the first six years of age. A blood test to screen for elevated lead is advised if the assessment finds a child is at risk.
- The Centers for Disease Control and Prevention and the American College of Obstetricians and Gynecologists advise doctors to assess pregnant women for risk of exposure to lead. If a woman has even one of several risk factors, such as living in an older home, she should be given a blood test to detect elevated lead levels.
Lead is a soft metal present in the environment. In the past, lead was used in paints, gasoline, water pipes, and other household products, such as the solder used in canned food. Housing built prior to 1978 may contain lead-based paint, lead-contaminated household dust and/or lead plumbing fixtures. State and federal policy changes to remove lead from gasoline (in 1990) and paint (in 1978) have greatly lowered the risks of lead exposure. However, older homes with lead paint and/or lead plumbing still exist, which is why lead poisoning remains a public health issue.
Exposure to lead can result in lifelong health problems, especially if it is ingested by a child or by a pregnant woman who then passes it to her fetus. Elevated amounts of lead in the body affect various organ systems, including the nervous system, the heart, kidneys, and liver. High lead levels in children can cause behavioral and learning problems, lower IQ, hyperactivity, slow growth, hearing problems, anemia, and even death. For pregnant women, high lead levels can cause loss of the fetus during pregnancy (miscarriage), early delivery, low birth weight, and high blood pressure in the mother.
Currently, questionnaires and/or blood tests may be used to screen people for lead exposure. In its review of the latest studies, the Task Force did find evidence that blood testing is effective in identifying people with elevated blood lead levels but also found that questionnaires used to identify people at risk of lead exposure are not accurate. The Task Force calls for more research, saying that questionnaires should be developed and validated to better determine who may be at risk and that more studies are necessary to evaluate newer lead testing methods, including point-of-care tests.
"We are calling for more research so clinicians can have better ways to prevent and treat health problems that can result from lead exposure," says Task Force member Michael Silverstein, M.D., M.P.H. vice chair of research for the Department of Pediatrics at the Boston University School of Medicine. Adds Silverstein: "Clinicians should use their best judgement about if and when to screen children and pregnant women without signs or symptoms for lead exposure and keep up to date on any concerns about lead in their community."
In addition to the health organizations mentioned above, different states have their own guidelines for lead testing. Individuals with questions about lead screening are encouraged to seek guidance from their healthcare practitioner and discuss with them recommendations and state laws.