Childhood lead poisoning in Zamfara State, Nigeria Therefore, we did not fully determine the geographic extent of childhood lead poison- ing in Zamfara State. Second, we could only sample approximately five children in each village. Although we oversampled children from homes with gold ore processing and sick children to increase the likelihood of detect- ing elevated BLLs, the number of villages with childhood lead poisoning might have been underestimated. Third, we used convul- sions and deaths as clinical indicators for lead poisoning because symptoms of lead poison- ing are generally nonspecific, and blood lead testing was unavailable at the beginning of the outbreak when the majority of affected chil- dren died. However, convulsions and deaths are not sensitive as markers of lead poisoning because they typically occur at BLLs that are higher than the levels detected in most blood samples collected from these villages, and con- vulsions and death are not specific for lead poisoning because they can result from other locally endemic diseases, including malaria and bacterial meningitis. Finally, we did not assess lead poisoning among children ≥ 5 years of age, adults, or livestock. Older children and adults are also at risk for harmful lead exposure and its adverse health effects, and children may be exposed in utero or through breast-feeding if their mothers have elevated BLLs. In addition, villagers may be exposed through consumption of lead-contaminated food or dairy products. Therefore, character- izing the depth and extent of lead poisoning in older children, adults, and livestock is an important topic for further investigation. Conclusion Childhood lead poisoning and lead contami- nation were widespread in the three surveyed LGAs in Zamfara State. Villages with recent gold ore–processing activity are at increased risk for childhood lead poisoning and lead contamination. We recommend cooperative action among international stakeholders and Nigerian federal, state, and local authorities to eliminate or reduce lead poisoning in this region. Joint efforts are needed to relocate gold ore–processing activities to locations inacces- sible to children, fully assess and remediate contaminated villages, communicate health messages and enhance risk awareness in affected communities, sustain screening and medical treatment programs, and continue to identify lead-contaminated villages. 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