Importance Childhood lead exposure is associated with neurobehavioral deficits. The effect of ar esidential lead hazard intervention on blood lead concentrations and neurobehavioral development remains unknown.
Objective To determine wehther a comprehensive residential lead-exposure reduction intervention completed during pregnancy could decrease residential dust lead loadings, prevent elevated blood lead concentrations, and improve childhood neurobehavioral outcomes.
Design, Settings, and Participant This longitudinal, community-based randomized clinical trial of pregnant women and their children, the Health Outcomes and measures of the Environment (HOME) Study, was conducted between march 1, 2003, and January 31, 2006. Pregnant women attending 1 of 9 prenatal care clinics affiliated with 3 hospitals in the Cincinnati, Ohio, metropolitan area were recruited. Of the 1263 eligible women, 468 (37.0%) agreed to participate and 355 women (75.8%) were randomized in this intention-to-treat analysis. Participants were randomly assigned to receive of 1 of 2 interventions designed to reduce residential lead or injury hazards. Follow-up on children took place at 1, 2, 3, 4, 5, and 8 years of age. Data analysis was performed from September 2, 2017, to May 6, 2018.
Main Outcomes and Measures Residential dust lead loadings were measured at baseline and when children were 1 and 2 years of age. At 1, 2, 3, 4, 5, and 8 years of age, the children's blood lead concentrations as well as behavior, cognition, and executive functions were assessed.
Results Of the 355 women randmized, 174 (49.0%) were assigned to the intervention group (mean [SD] age at delivery, 30.1 (5.5) years; 119 [68.3%] self-identified as non-Hispanic white) and 181 (50.9%) to the control group (mean [SD] age at delivery, 29.2 [5.7] years; 123 [67.9%] self-identified as non-Hispanic white). The intervention reduced the dust lead loadings for the floor (24%; 95% CI -43% to 1%), windowsill (40%; CI, -60% to -11%), and window trough (47%; 95% CI, -68% to -10%) surfaces. The intervention did not statistically significantly reduce childhood blood lead concentrations (-6%; 95% CI, -17% to 6%; P= .29). Neurobehavioral test scores were not statistically different between children in the intervention group than those int he control group except for a reduciton in anxiety scores int he intervention group (B= -.16; 95% CI, -.32 to -0.1; P=.04).
Conclusions and Relevance Residential lead exposures, as well as blood lead concentrations in non-Hispanic black children, were reducded through a comprehensive lead-hazard intervention without elevating the lead body burden. However, this decrease did not result in substanttive neurobehavioral improvements in children. (Author abstract)