Lead exposure can cause permanent neurological damage in children younger than 5 years of age because their bodies are developing rapidly and they tend to put their hands or other objects, which might be contaminated with lead dust, into their mouths.
Permanent neurologic damage and behavioral disorders are associated with blood lead levels (BLLs) at or below 5 µg/dL. The most common source of lead for children in the United States is lead paint. When lead paint deteriorates into flakes, chips, or dust, it is easily inhaled or ingested by small children.
In 1991, CDC recommended that state or local health departments should perform follow-up testing of children with BLLs ≥10 µg/dL. In 1995, the Council of State and Territorial Epidemiologists (CSTE), in collaboration with CDC, added elevated BLLs to the list of reportable conditions.
In May 2012, the Advisory Committee on Childhood Lead Poisoning Prevention (ACCLPP) recommended using reference ranges to identify elevated BLLs. ACCLPP recommended that the upper value of the reference range should be based on the 97.5th percentile of the lead levels contained in the National Health and Nutritional Examination Survey (NHANES). Currently, a cutoff value of 5 µg/dL is used by clinical and public health care providers to identify children with elevated BLLs. At this low level, the total allowable error is +/-4 ug/dL.
Children insured through Medicaid are required to have blood lead level tests at ages 1 and 2, but some children are not screened. Some states require testing, but requirements vary. The American Academy of Pediatrics recommends blood lead level testing only for children who are determined to be at risk for lead exposure or who live in high prevalence areas. Likewise, CDC’s 2012 recommendation discourages universal screening in favor of primary prevention.
CDC asks state and local health departments to report all blood lead test data for children to the Healthy Homes and Lead Poisoning Prevention Program (HHLPPP), regardless of the BLL. In 2014, a total of 32 jurisdictions reported data to HHLPPP.
Today at least 4 million households in the United States have children living in them that are being exposed to high levels of lead. Approximately 500,000 children between the ages of 1 and 5 years old have blood lead levels above 5 µg/dL.
Raymond J and Brown MJ, Childhood Blood Levels in Children Aged <5 years – United States, 2009-2014. MMWR Surveillance Summaries, Jan 20, 2017;66 (3):1-10.