Surface dust wipes are the best predictors of blood leads in young children with elevated blood lead levels

The correlations showed an association for isotopic ratios in blood and wipes (r=0.52, 95% CI 0.19-0.74), blood and soil (r=0.33, 95% CI −0.05-0.62), and blood and paint (r=0.56, 95% CI 0.09-0.83). The regression analyses indicated that the only statistically significant relationship for blood isotopic ratios was with dust wipes (B=0.65, 95% CI 0.35-0.95); there were no significant associations for lead concentrations in blood and environmental samples. There is a strong isotopic correlation of soils and house dust (r=0.53, 95% CI 0.20-0.75) indicative of a common source(s) for lead in soil and house dust. In contrast, as with the regression analyses, no such association is present for bulk lead concentrations (r=−0.003, 95% CI −0.37-0.36), the most common approach employed in source investigations. In evaluation of the isotopic results on a case by case basis, the strongest associations were for dust wipes and blood.