Related Experiment Videos
Update: blood lead levels--United States, 1991-1994
Insights
Childhood lead exposure remains a concern, with blood lead levels (BLLs) continuing to decrease nationally. However, elevated BLLs disproportionately affect certain demographics, highlighting ongoing environmental health disparities.
Area of Science:
- Environmental Health
- Pediatric Toxicology
- Public Health Surveillance
Background:
- Lead is a toxicant affecting multiple organ systems, posing particular risks to children's developing nervous systems.
- Even low blood lead levels (BLLs) can negatively impact child behavior and development.
- The National Health and Nutrition Examination Surveys (NHANES) are crucial for monitoring U.S. population BLLs.
Purpose of the Study:
- To update national BLL estimates using recent NHANES data.
- To identify trends in BLLs among the U.S. population, especially children.
- To examine demographic and socioeconomic factors associated with elevated BLLs in young children.
Main Methods:
- Analysis of data from Phase 2 of the National Health and Nutrition Examination Survey III (1991-1994).
- Calculation of geometric mean BLLs and prevalence of elevated BLLs (≥10 µg/dL) for various age groups.
- Statistical examination of factors associated with elevated BLLs in children aged 1-5 years.
Main Results:
- National BLLs in the U.S. population (aged ≥1 year) continued to decline between 1988-1991 and 1991-1994.
- The geometric mean BLL for persons aged 1-74 years decreased significantly from NHANES II to NHANES III Phase 1.
- Elevated BLLs in children aged 1-5 years were more prevalent among those who were poor, non-Hispanic black, lived in large metropolitan areas, or resided in older housing.
Conclusions:
- Continued decline in national BLLs indicates progress in lead exposure reduction efforts.
- Persistent disparities in elevated BLLs among young children highlight the need for targeted interventions for vulnerable populations.
- Environmental and socioeconomic factors remain critical determinants of childhood lead exposure.
Abstract:
Lead is an environmental toxicant that may deleteriously affect the nervous, hematopoietic, endocrine, renal, and reproductive systems. Lead exposure in young children is a particular hazard because children absorb lead more readily than do adults and because the developing nervous systems of children are more susceptible to the effects of lead. Blood lead levels (BLLs) at least as low as 10 micrograms/dL can adversely affect the behavior and development of children. CDC's National Health and Nutrition Examination surveys (NHANES), an ongoing series of national examinations of the health and nutritional status of the civilian noninstitutionalized population, have been the primary source for monitoring BLLs in the U.S. population. From NHANES II (conducted during 1976-1980) to Phase 1 of NHANES III (conducted during October 1988-September 1991), the geometric mean (GM) BLL for persons aged 1-74 years declined from 12.8 micrograms/dL, and the prevalence of elevated BLLs (BLLs > or = 10 micrograms/dL) decreased from 77.8% to 4.4%. This report updates national BLL estimated with data from Phase 2 of NHANES III (conducted during October 1991-September 1994), which indicate that BLLs in the U.S. population aged > or = 1 year continued to decrease and that BLLs among children aged 1-5 years were more likely to be elevated among those who were poor, non-Hispanic black, living in large metropolitan areas, or living in older housing.