In March 2010 Medecins Sans Frontieres (MSF) discovered an epidemic of lead poisoning in Zamfara state in northern Nigeria. Subsequent investigations by the Centers for Disease Control (CDC), the World Health Organization (WHO) and the Zamfara State Ministry of Health (ZMoH) confirmed that hundreds of children under age five years were at risk of death or long-term irreversible health effects due to extremely high levels of lead and mercury. At least 10,000 people were estimated to be affected overall. The source of the outbreak was associated with artisanal gold ore processing that occurs in the villages. For several months grinding operations were conducted at numerous sites in villages and crushing, washing, and gold recovery were undertaken within the residential compounds. A particularly dangerous ore, of high lead content sometimes exceeding 10% lead, was introduced into the processing stream in early 2010.

At the request of the Zamfara State government, the United States (US) and Nigerian CDC conducted an assessment of the extent of the epidemic; at CDC’s request, TerraGraphics Environmental Engineering (TG) and the international NGO Blacksmith Institute (BI) assisted with and provided equipment and expertise in this survey. The assessment confirmed the lead poisoning diagnosis and 163 deaths among children less than five years of age in two villages, tested several hundred children and adults, identified the principal exposure routes, and quantified contamination levels in environmental media in the villages. Of the children tested in two villages, 100% exceeded 10 ug/dL (the international standard maximum for lead in blood), with some levels measuring as high as 700 ug/dL.

The ZMoH, CDC, WHO, MSF and Nigerian federal authorities collaborated to develop a medical response to provide oral chelation therapy for children five years of age and under. The efficacy of chelation therapy is compromised if medically treated children return to contaminated homes. This necessitated immediate remediation of the villages to secure clean environments for the children returning from treatment as well as to reduce lead exposure to older children and adults to whom chelation was not available.

From June 2010 to March 2011, TerraGraphics advised the Zamfara State Ministry of Environment (ZMoE) in conducting environmental decontamination in seven villages in collaboration with Blacksmith Institute and local authorities. Contaminated soil was removed to secure landfills and replaced with clean soil. In total, seven villages were remediated, including 430 residential compounds, 107 exterior areas and 23 processing ponds, allowing MSF to provide chelation treatment for more than 1000 children. The technical expertise was provided by TerraGraphics, but the remediation was carried out by ZMoE, local government, and village personnel. TerraGraphics trained more than 200 ZMoE, local government, village and private personnel, building Nigerian capacity to conduct future remediation activities.

In addition, the town of Bagega, where over 1500 children 5 years and younger continue to be exposed, has been comprehensively characterized and a remedial design completed. Pending additional funding, TerraGraphics and its partners are prepared to assist Zamfara State and the local governments to undertake and sustain future cleanup activities in Bagega and other impacted villages.