Rural-urban blood lead differences in North Carolina children.

OBJECTIVE: To examine the prevalence of and risk factors for having a blood lead elevation among young children in a predominantly rural state.

METHODS: 20,720 North Carolina children at least 6 months and < 6 years of age were screened between November 1, 1992 and April 30, 1993 using either capillary or venous measurements of blood lead. Children were tested through routine screening programs that target low-income families and, hence, were not randomly selected. Eighty-one percent of the children were screened through local public health departments, and 19% were tested at private clinics.

RESULTS: The estimated prevalences of having an elevated blood lead level among those tested were: 20.2% (> or = 10 micrograms/dL), 3.2% (> or = 15 micrograms/dL), and 1.1% (> or = 20 micrograms/dL). Black children were at substantially increased risk of having a blood lead > or = 15 micrograms/dL (odds ratio (OR) = 2.1, 95% confidence interval (CI) = 1.7 to 2.5). Children aged 2 years old had an elevated risk (OR = 1.4, 95% CI = 1.1 to 1.7) compared to 1-year-olds, and males were at slightly increased risk (OR = 1.2, 95% CI = 1.0 to 1.4). Living in a rural county was nearly as strong a risk factor as race (OR = 1.9, 95% CI = 1.6 to 2.4). The effect of rural residence was even greater among certain subgroups of children already at highest risk of having an elevated blood lead. The type of clinic (public vs private) where a child was screened was not associated with blood lead outcome. These same trends were seen for children with blood lead levels > or = 20 micrograms/dL.

CONCLUSIONS: Among children screened from rural communities, the prevalence of elevated blood lead is surprisingly high. Though few physicians have embraced universal lead screening, these data support the need for greater awareness of lead exposure in children living outside of inner-cities.