Household interventions for prevention of domestic lead exposure in children

Abstract

Background: Lead poisoning is associated with physical, cognitive and neurobehavioral impairment in children and many household interventions to prevent lead exposure have been trialled. Objectives: To determine the effectiveness of household interventions in preventing or reducing lead exposure in children as measured by reductions in blood lead levels and/or improvements in cognitive development. Search strategy: Trials were identified through electronic searches of CENTRAL 2006 (Issue 1), MEDLINE 1966 to March 2006, and thirteen other electronic databases and contacting experts to find unpublished studies. Selection criteria: Randomised and quasi randomised trials of household educational or environmental interventions to prevent lead exposure in children where at least one standardised outcome measure was reported. Data collection and analysis: Two reviewers independently reviewed all eligible studies for inclusion, assessed study quality and extracted data. Triallists were contacted to obtain missing information. Main results: Twelve studies (2239 children) were included. All studies reported blood lead level outcomes and none reported on cognitive or neurobehavioural outcomes. Studies were subgrouped according to their intervention type. Meta-analysis of both continuous and dichotomous data was performed for subgroups where appropriate. Educational interventions were not effective in reducing blood lead levels (continuous: WMD 0.13, 95% CI -0.30, 0.56, I2= 41.6; dichotomous ≥ 10μg/dL (≥ 0.48μmol/l): RR 1.02 (95% CI 0.79, 1.30, I2=0); dichotomous ≥ 15μg/dL (≥0.72μmol/l): RR 0.60, 95% CI 0.33, 1.09, I2 =0). Meta-analysis of the dichotomous data for the dust control subgroup found no evidence of effectiveness. The studies using soil abatement (removal and replacement) and combination intervention groups were not able to be meta-analysed due to substantial differences between studies. Authors' conclusions: Currently there is no evidence of effectiveness for household interventions for education or dust control measures in reducing blood lead levels in children as a population health measure. There is insufficient evidence for soil abatement or combination interventions. Further trials are required to establish the most effective intervention for prevention of lead exposure. Key elements should include longer term follow up and measures of compliance as well as performing trials in developing countries and differing socio-economic groups in developed countries. Copyright © 2008 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.