title: A follow-up cross-sectional study of environmental lead exposure in early childhood in urban South Africa.
abstract: BACKGROUND
  Lead exposure has significant detrimental effects on the health and wellbeing of children. In resource-poor countries, information on the extent of lead exposure is often inadequate owing to the lack of surveillance and screening programmes.
  
  
  OBJECTIVE
  To determine the degree of lead exposure in children residing in South African urban areas.
  
  
  METHODS
  A cross-sectional survey was conducted in schools in Johannesburg, Cape Town and Kimberley in 2007 - 2008. Blood lead levels were assessed in a total of 1 349 grade 1 children using the LeadCare Analyser system. Parents completed a structured questionnaire on sociodemographic profiles and risk factors to provide information about socioeconomic status and other risk factors for lead exposure.
  
  
  RESULTS
  Blood lead levels ranged from 0.8 - 32.3 μg/dl. The mean blood lead level in the total sample was 7.97 μg/dl; 74% had blood lead levels ≥5 μg/dl. The highest proportion (84%) of children with blood lead levels ≥5 μg/dl was in Johannesburg. In the multivariate analysis, socioeconomic status was significantly associated with blood lead levels ≥5 μg/dl.
  
  
  CONCLUSIONS
  Lead exposure in South African urban areas remains widespread. The risk of lead poisoning in some areas and certain groups of children may be increasing despite the phasing out of lead-containing petrol. Children living in poverty continue to be the most vulnerable.
authors.affiliation: South African Medical Research Council, Johannesburg, South Africa; School of Public Health, University of the Witwatersrand, Johannesburg, South Africa. nisha.naicker@mrc.ac.za.
authors.forename: Nisha
authors.initials: N
authors.lastname: Naicker
authors.forename: Angela
authors.initials: A
authors.lastname: Mathee
authors.forename: Brendon
authors.initials: B
authors.lastname: Barnes
mesh_terms: D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis / Q000517:prevention & control / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007854:Lead / Q000097:blood*; D007855:Lead Poisoning / Q000097:blood / Q000453:epidemiology / Q000209:etiology; D008297:Male; D059392:Petroleum Pollution / Q000009:adverse effects / Q000517:prevention & control / Q000706:statistics & numerical data; D012044:Regression Analysis; D018570:Risk Assessment; D012307:Risk Factors; D012572:School Health Services / Q000706:statistics & numerical data; D012959:Socioeconomic Factors; D013019:South Africa / Q000453:epidemiology; D014505:Urban Population / Q000706:statistics & numerical data
chemical_list: D007854:Lead