Outbreak of acute childhood lead poisoning in Zamfara State, Nigeria, 2010

Background: In May, 2010 the Nigerian Ministry of Health assembled a team of national and international organizations including Centers for Disease Control and Prevention, World Health Organization, and Medecins Sans Frontieres, to investigate reports of child death due to lead poisoning in multiple villages in northwestern Nigeria. Methods: A cross-sectional house-to-house questionnaire was administered in every family compound in one affected village and to those in the central area of a second affected village. Blood from available children aged 2 – 48 months and soil samples collected within family compounds were analyzed for lead. Results: We surveyed 119 family compounds. In total 118 of 463 (26%) children aged <5 years had died since May 2009. Blood samples collected from 60% (205/345) of living children revealed lead poisoning (≥10 µg/dL), and 97% of children had levels above the threshold (≥45 µg/dL) for initiating chelation therapy. Two-thirds of households processed gold ore inside their family compounds. Breaking, drying, separating and washing ore were each associated with child death (p < 0.05). Overall, children living in family compounds that processed ore were 3 times more likely to die than children living in compounds that did not process ore (OR 3.02; CI 1.2, 7.4). Discussion: This outbreak was caused by gold ore processing activities putting children in family compounds that process ore at high risk for lead poisoning. Ongoing control measures include chelation therapy, public health education, and controlling mining activities. Lead contaminated family compounds have undergone environmental remediation to reduce further child mortality.