No safe blood lead levels (BLLs) in children have been identified. Lead is harmful to fetuses and young children, adversely affecting their developing nervous systems. Permanent neurological damage and behavioral disorders have been associated with BLLs that are moderate or lower, and high BLLs can lead to severe neurological problems such as seizures, comas, and death.Lead exposure can also cause learning disabilities, lowered intelligence or behavioral problems. Recent evidence suggests that even blood levels lower than previously thought to be clinically significant may have adverse health effects. In addition, exposure to lead in early childhood may result in deleterious effects on neurodevelopment that persist into adolescence. Although lead was banned from residential paint in 1978, it remains an issue in houses built before the ban, and can be found in other environmental sources, such as soil and water, as well as thousands of commercial applications. Because lead poisoning often occurs with no observable symptoms, it may go unrecognized, implying a need for regular BLL testing.
Due to increased public recognition of the hazards associated with lead, and related policy responses as well as secular changes, BLLs have decreased substantially in the past four decades. Between 1973 and 1995, gasoline containing lead was phased out, and federal regulations were enacted reducing allowable lead levels in drinking water, banning lead from paint, and restricting its use in plumbing materials, food and beverage containers, playground equipment, and various household products.
The percentage of children under the age of 6 who were tested by their physician and had elevated blood levels has fallen sharply in the past 14 years. In 1997, 7.6 percent of children tested had high blood levels; in 2015, the proportion was 0.5 percent. The percentage tested with moderate BLLs fell from 6.6 to 3.3 percent between 2010 and 2015. (Figure 1)
Other, older sources of data show a similar pattern of decreasing incidence. Between 1988 and 1991, 8.6 percent of all children ages 1 to 5 (not just the ones who were taken in for testing) had high blood lead levels. Between 1991 and 1994, 4.4 percent of all children, and between 1999 and 2004, 1.4 percent of all children ages 1 to 5 had high blood lead levels. The proportion of all children, ages 1 to 5, with moderate BLLs (greater than or equal to 5 µg/dL) fell from 8.6 between 1999 and 2002 to 4.1 percent between 2003 and 2006, and then to 2.6 percent between 2007 and 2010.
Although disparities in the proportion of elevated blood levels among various subpopulations of children are no longer significant, there continue to be inequities in risk for exposure to lead. In addition, mean BLLs remain higher for children in low-income families, non-Hispanic black children, and children who live in older housing. In-utero exposure to lead is a significant problem among some new immigrants to the U.S.
Selected state and county estimates are available for children under age six are available from the Centers for Disease Control and Prevention.
Data from selected European countries from 1991 to 2008 are available here.
The federal government has set national goals related to reducing children’s exposure to lead, through its Healthy People 2020 initiative. The primary goals are to eliminate elevated blood levels in children and to reduce the mean blood lead levels in children, from 1.8 µg/dL in 2005-08, to 1.6 µg/dL by 2020. Supporting these are additional goals to increase the proportion of older houses that are tested for lead, as well as the proportion that are found to be safe, inspect school drinking fountains for lead, and increase state monitoring of lead-linked diseases.
More information is available here. (Goals EH-8, 16.7, 17, 18, 20.3, and 22.1)
As summarized by the American Academy of Pediatrics, there are no treatments that have been found to be effective in mitigating the permanent negative developmental effects of lead poisoning. Thus, prevention is a priority. Eliminating the major sources of lead exposure, strengthening existing health standards for lead in paint, dust, and water, universal blood lead screening for children with identified risk factors, and ongoing case management for those children with levels of five micrograms and above are important methods of preventing and managing lead poisoning in children.
High BLLs are defined as greater than or equal to 10 micrograms per deciliter (µg/dL) and are based on blood samples analyzed in laboratories. Moderate BLLs are defined as greater than or equal to 5 micrograms per deciliter (µg/dL).
Data by gender, race/ethnicity, and age: Department of Health and Human Services Centers for Disease Control and Prevention. (2003). Surveillance for elevated blood lead levels among children – United States 1997-2001. Morbidity and Mortality Weekly Report, 52(SS-10). Available at: http://www.cdc.gov/mmwr/PDF/ss/ss5210.pdf .
Data for 1997-2015: Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Environmental Health. (2016). CDC’s national surveillance data (1997-2015): Tested and confirmed elevated blood lead levels by state, year and blood lead level group for children <72 months. Available at: http://www.cdc.gov/nceh/lead/data/national.htm
State and local health department data reported to the Centers for Disease Control and Protection Blood Lead Surveillance System.
|Native American/Alaska Native||5.5||4.5||2.6||1.7||1.5||–||–||–||–||–|
|0 to 11 months||2.2||1.9||1.4||1.2||0.9||–||–||–||–||–|
|12 to 23 months||6.3||5.6||4.1||3.2||2.5||–||–||–||–||–|
|24 to 35 months||9.6||8.5||6.5||5.2||4.0||–||–||–||–||–|
|36 to 47 months||9.9||8.6||6.9||5.6||4.2||–||–||–||–||–|
|48 to 59 months||8.8||7.7||6.0||4.8||3.6||–||–||–||–||–|
|50 to 71 months||8.8||8.1||6.5||5.2||3.8||–||–||–||–||–|
|– Data are not available.
1High blood lead levels are defined as greater than or equal to 10 micrograms per deciliter (µg/dL). Moderate blood lead levels are defined as greater than or equal to 5 µg/dL.
Sources: Data by gender, race/ethnicity, and age: Department of Health and Human Services Centers for Disease Control and Prevention. (2003). Surveillance for elevated blood lead levels among children – United States 1997-2001. Morbidity and Mortality Weekly Report, 52(SS-10). Available at: http://www.cdc.gov/mmwr/PDF/ss/ss5210.pdf. Data for 1997-2015 trends: Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Environmental Health. (2016). CDC’s national surveillance data (1997-2015): Tested and confirmed elevated blood lead levels by state, year and blood lead level group for children <72 months. Available at: http://www.cdc.gov/nceh/lead/data/national.htm
Brown, M. J. & Margolis, S. (2012). Lead in drinking water and human blood levels in the United States. MMWR, 61(Supplement), 1-9.
Raymond, J., & Brown, M. J. (2015). Childhood blood lead levels – United States, 2007-2012. Morbidity and Mortality Weekly Report: 62(54); 76-80. https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6254a5.htm
American Academy of Pediatrics. (2016). Prevention of childhood lead toxicity. Policy Statement. Retrieved from http://pediatrics.aappublications.org/content/early/2016/06/16/peds.2016-1493
Center for Disease Control and Prevention, National Center for Environmental Health. (2002). Managing elevated blood lead levels among young children: Recommendations from the Advisory Committee on Childhood Lead Poisoning Prevention. Available at: http://www.cdc.gov/nceh/lead/casemanagement/caseManage_main.htm
Jones, R. L., Homa, D. M., Meyer, P. A., Brody, D. J., et al. (2005). Trends in blood lead levels and blood lead testing among US children aged 1 to five years, 1988-2004. Pediatrics, 123(3), e376-e385.
Wheeler, W. (2013). Blood Lead Levels in Children Aged 1–5 Years — United States, 1999–2010. MMRW, 62(13), 245-248. Available at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6213a3.htm.
American Academy of Pediatrics. Op. cit.
Child Trends Databank. (2017). Lead Poisoning. Available at: https://www.childtrends.org/?indicators=lead-poisoningLast updated: January 2017