Prevalence of blood lead levels +AD4-or+AD0- 5 micro g/dL among US children 1 to 5 years of age and socioeconomic and demographic factors associated with blood of lead levels 5 to 10 micro g/dL, Third National Health and Nutrition Examination Survey, 1988-1994

Abstract

OBJECTIVES: As part of an investigation into the impact of a potential revision in federal childhood lead poisoning prevention policy that would result in screening children for blood lead levels (BLLs) +AD4-or+AD0-5 micro g/dL rather than the current 10 micro g/dL, we analyzed the most recent available, nationally representative data to identify prevalence of BLLs +AD4-or+AD0-5 micro g/dL and socioeconomic and demographic characteristics of 1- to 5-year-old children with BLLs +AD4-or+AD0-5 but +ADw-10 micro g/dL. METHODS: We performed statistical analyses on data from the Third National Health and Nutrition Examination Survey (NHANES III) (1988-1994) to describe trends in BLLs +AD4-or+AD0-5 micro g/dL overall and among subpopulations of children +ADw-6 years old and to compare risk factors for falling within 1 of 3 groups of children (those with BLLs +AD4-or+AD0-5 but +ADw-10 micro g/dL+ADs- +AD4-or+AD0-10 but +ADw-20 micro g/dL+ADs- and +AD4-or+AD0-20 micro g/dL) using the group reported as 0.7 to +ADw-5 micro g/dL as the referent. RESULTS: Overall prevalence of BLLs +AD4-or+AD0-5 micro g/dL among 1- to 5-year-old children was 25.6+ACU-, although most (76+ACU-) of these children had BLLs +ADw-10 micro g/dL. Children with BLLs +AD4-or+AD0-5 micro g/dL included 46.8+ACU- of non-Hispanic black children, 27.9+ACU- of Mexican American children, and 18.7+ACU- of non-Hispanic white children+ADs- 42.5+ACU- of children in housing built before 1946, 38.9+ACU- of children in housing built between 1946 and 1973, and 14.1+ACU- of children in housing built after 1973 had BLLs +AD4-or+AD0-5 micro g/dL. Compared with non-Hispanic white children, non-Hispanic black children were 3 times more likely to have a BLL +AD4-or+AD0-5 but +ADw-10 micro g/dL, 7 times more likely to have a BLL of 10-20 micro g/dL, and 13.5 times more likely to have a BLL +AD4-or+AD0-20 micro g/dL. Similar increases in the association between risk factor and BLL were seen with respect to other known risk factors including age of housing, region of the country, and poverty. CONCLUSIONS: The high prevalence of BLLs +AD4-or+AD0-5 micro g/dL overall and within US subpopulations will be an important variable in any change in screening and intervention criteria. However, most children with BLLs +AD4-or+AD0-5 micro g/dL are below the current intervention level of 10 micro g/dL. Exposure to lead from multiple sources is suggested by the prevalence of BLLs +AD4-or+AD0-5 micro g/dL but +ADw-10 micro g/dL among children with uncertain risk factors. The probable presence of one or more known risk factors for childhood lead poisoning increases as BLL increases