Blood lead levels in children from lower socioeconomic communities in Denver, Colorado.

Abstract

We measured blood lead levels and inquired about environmental exposure pathways in 443 children aged 6 mo to 6 y in four lower socioeconomic Denver, Colorado, neighborhoods. Two neighborhoods were adjacent to a cadmium refinery. Eight percent of the children had blood lead levels > or = 10 micrograms/dl and 45% were below the detection limit of 4 micrograms/dl. Statistical analyses specific to the problem of below-detection values (i.e., dichotomization of variables, the probability plot method of estimation, and the bootstrap estimate of the standard error) were conducted to detect neighborhood differences. A child who lived in Globeville, the neighborhood surrounding the refinery, had a slightly higher probability of having a blood lead level > or = 5 micrograms/dl. Yet, the results as a whole documented the striking decline in blood lead levels in urban children after the deleading of gasoline.