A SIDE-BY-SIDE COMPARISON OF DUST COLLECTION METHODS FOR SAMPLING LEAD-CONTAMINATED HOUSE-DUST

The Environmental Protection Agency is required to set a standard for lead-contaminated house dust, but whether dust lead loading (mu g/ft(2 )) or concentration (mu g/g) is more predictive of children's blood le ad levels, which dust collection method should be used, and which surf aces should be sampled are unknown. Using a random sample of sequentia l births, we enrolled 205 urban children, 12 to 30 months of age, who had lived in the same house since at least 6 months of age. Samples of dust were obtained from predetermined surfaces in each child's reside nce using a wipe method and two vacuum methods, the Baltimore repair a nd maintenance method (BRM) and the dust vacuum method (DVM). Other po tential sources of environmental exposure also were analyzed for lead, including soil, water, and paint. In general, dust lead loading is mo re predictive of children's blood lead levels than is dust lead concen tration. Dust lead loading as measured with the BRM sampler explained more of the variation in children's blood lead levels than did wipe lo ading and DVM loading (13.7, 10.1, and 5.9%, respectively, adjusted fo r other significant predictors). The partial correlation between BRM l ead loading and children's blood lead was significantly different than that for DVM lead loading, but it was not significantly different tha n that for wipe lead loading. Of the four surfaces measured, noncarpet ed floors and interior window sills or wells were significantly associ ated with children's blood lead levels in multiple regression models. These data indicate that dust lead loading is more predictive of child ren's blood lead levels than is dust lead concentration and that, to d etermine if a housing unit is safe for children, noncarpeted floors an d interior window sills or window wells should be measured using eithe r the BRM or wipe sampling method. (C) 1995 Academic Press, Inc.