POLLUTION LOCATOR|Blood Lead Levels in Children In the United States

The U.S. Centers for Disease Control and Prevention (CDC) defines a blood lead of 10 micrograms (ug) per deciliter of blood (dL) as a level of concern. The threshold of 10 ug/dL was established because scientists studying large populations observed adverse health effects, including problems with learning and behavior, in groups of children with blood lead elevations at or above this level. For children with persistent blood lead levels above 10 ug/dL, CDC recommends further testing along with steps to reduce ongoing lead exposure. At higher blood lead levels (>20 ug/dL), more aggressive measures are recommended.

Monitoring data from the CDC's
Second National Report on Human Exposure to Environmental Chemicals indicate that 2.2% of U.S. children aged 1-5 (434,000 children) have blood lead levels greater than or equal to 10 ug/dL. The 1999-2000 monitoring results indicate there has been a significant decline in the number of children at risk due to high blood lead levels: in 1994-1995, 4.4% (890,000 children) exceeded CDC's level of concern. Currently, mean blood lead levels are generally well below the level of concern across all age groups.

While reductions in the overall percent of children with high blood lead levels is good news, the data are unfortunately not good enough to characterize whether this trend has occurred across all income and racial groups. The number of young children tested in the CDC survey was too small to make reliable estimates of rates for different population subgroups, and hence does not illuminate disparities by income or race. For all age groups, the report estimates higher geometric mean blood lead levels for Black and Hispanic persons compared to Whites. Older Americans continue to show some higher blood lead levels from prior exposure stored in the body and from occupational and other adult exposures.

State surveillance data in the CDC report Surveillance for Elevated Blood Lead Levels among Children -- United States, 1997-2001 offer some information on population subgroups, although the data has significant limitations. The state data indicate a complementary decline in the rates of elevated blood lead levels, across the population as a whole and within racial and ethnic groups.

Screening for elevated blood lead is necessary to confirm exposure, because often the symptoms of childhood lead poisoning can be difficult or impossible to recognize. These effects can include reduced IQ and attention span, hyperactivity, reading and learning difficulties, and hearing loss. A test to determine a child's blood lead level is usually the only way to know if a child is exposed to lead. Screening is performed using a blood lead test, in which a small sample of blood is taken from a child, via a fingerstick or by drawing blood from a vein. The blood sample is then analyzed by special equipment that determines the amount of lead in the child's blood.

Regardless of where they live, all children enrolled in Medicaid must receive lead screening. The Centers for Medicare and Medicaid, the federal agency that oversees the Medicaid program, requires blood lead screening for all children enrolled in Medicaid at 12 and 24 months, and for any child 36-72 months of age who has no record of prior screening. For children not enrolled in Medicaid, CDC recommends that, because the risk for lead exposure is high in some places and low in others, state health departments examine information on exposure sources and blood lead levels in their states and decide on how blood lead screening should be conducted for children who are state residents. To find out your state's policy on lead screening, contact the state health department program.

More information on the above surveys is available from the CDC. The CDC report Update: Blood Lead Levels -- United States, 1991-1994 explains the relationships between lead poisoning and risk factors such as age of housing, income, race and other factors

For more information on lead screening and follow-up care, contact the CDC. For more information on state programs to identify and help children with elevated blood lead levels, see the listing of state programs available from the National Council of State Legislatures. See also the Alliance for Healthy Homes' Another Link in the Chain and the National Center for Lead-Safe Housing.