From the Guidelines
Children should be screened for lead poisoning at 12 to 24 months of age if they live in communities or census block groups with ≥25% of housing built before 1960 or a prevalence of children’s blood lead concentrations ≥5 μg/dL (≥50 ppb) of ≥5%. This screening typically involves a blood test to measure lead levels, with venous blood samples being more accurate than capillary samples 1. Some healthcare providers may recommend additional screening at 9 months for children at higher risk. Risk factors that may warrant earlier or more frequent screening include living in older homes built before 1978 (when lead paint was banned), having siblings or playmates with lead poisoning, living near industrial sources of lead, or having parents who work with lead. For children who weren't tested at the recommended ages, screening should be done as soon as possible before age 6.
Key Considerations for Screening
- The American Academy of Pediatrics (AAP) recommends targeted screening of children for elevated blood lead concentrations if they are 12 to 24 months of age and live in high-risk areas 1.
- Lead screening is crucial because even low levels of lead exposure can cause irreversible neurological damage, affecting brain development, learning abilities, and behavior.
- Young children are particularly vulnerable because they absorb lead more readily than adults and often put their hands and objects in their mouths, increasing exposure risk.
- The major sources of lead exposure among U.S. children are lead-contaminated dust, deteriorated lead-based paint, and lead-contaminated soil 1.
Recommendations for Follow-Up
- For children with blood lead concentrations <5 μg/dL (<50 ppb), review laboratory results with the family and repeat the blood lead concentration in 6–12 months if the child is at high risk for lead exposure or if the risk profile increases 1.
- For children with blood lead concentrations ≥5 μg/dL (≥50 ppb), perform steps as described above and retest venous blood lead concentration within 1–3 months to verify that the lead concentration is not rising 1.
From the Research
Screening for Lead Poisoning in Children
The Centers for Disease Control and Prevention (CDC) recommends screening all Medicaid-eligible children at 12 months and again at 24 months, or at least once between 36 and 72 months if not previously screened 2. This is because asymptomatic lead poisoning has become more common in children, and blood lead levels of less than 5 µg per dL are associated with impairments in neurocognitive and behavioral development that are irreversible.
Risk Factors for Lead Poisoning
Risk factors for lead poisoning include:
- Age younger than five years
- Low socioeconomic status
- Living in housing built before 1978
- Use of imported food, medicines, and pottery Children with these risk factors should be screened for lead poisoning, even if they are older than 3 years 2, 3.
Targeted Screening Guidelines
The CDC recommends that states and cities formulate their own targeted screening guidelines based on local risk factors 2. Universal screening is recommended in areas where more than 27% of the housing was built before 1950, or where at least 12% of children 12 to 36 months of age have blood lead levels greater than 10 µg per dL.
Screening Beyond 3 Years of Age
Some studies suggest that universal screening for lead poisoning beyond 3 years of age may not be warranted in all communities 4. However, children living in high-risk areas with risk factors such as living in housing built before 1950 or having a previous history of lead poisoning should have a blood lead test at older ages 3, 5.
Summary of Screening Recommendations
- Screen all Medicaid-eligible children at 12 months and again at 24 months, or at least once between 36 and 72 months if not previously screened
- Screen children with risk factors such as living in housing built before 1978 or having a previous history of lead poisoning
- Consider targeted screening guidelines based on local risk factors
- Universal screening may not be necessary in all communities, but children living in high-risk areas should be screened at older ages 2, 4, 3, 5