Zamfara And Niger States, Nigeria
In March 2010, Médecins Sans Frontières (Doctors Without Borders, MSF) discovered an outbreak of acute lead poisoning in remote villages of Zamfara State, Nigeria. More than 17,000 people were poisoned and 400 children died as a result of soil lead contamination associated with artisanal and small-scale gold mining (ASGM) activities. In 2015, 30 children died during a similar lead poisoning outbreak in neighboring Niger State. TIFO and other international organizations collaborated with Nigerian civil and traditional governments to implement an environmental health response.
Remediation activities were modeled on US EPA “Superfund” protocols. Post-cleanup activities include medical treatment in MSF clinics, monitoring the sustainability of the remediation, and implementation of safer mining practices. The epidemic has been characterized as unprecedented, and the ensuing cleanup one of the largest and most comprehensive ever undertaken by an African government.
Remediating the villages presented numerous resource, logistic, cultural, institutional, and technical challenges. The cleanup evolved from an emergency response initially directed by international personnel to a multi-disciplinary program carried out by Nigerian federal, state, and local governments. Scroll down for more information.
ASGM is defined by low-technology and typically includes informal organizational structures. Mercury is commonly used to select for gold particles.
In Nigeria, certain gold ores contain high concentrations of lead. The dusts and wastes produced during processing contain up to 10% lead (100,000 mg/kg).
Remediation involved physically removing contaminated soils. Cleanup was done using local labor and locally available agricultural tools.
After excavated areas are tested to confirm successful removal of contamination, "clean" uncontaminated soils were placed in homes and public areas.
Children are most susceptible to lead poisoning. In Zamfara, thousands of children have benefited from remediation and medical treatment.
Personnel from the Zamfara Ministry of Environment and the Anka Local Government were trained in and led the risk assessment and remediation activities.
Source of Lead Poisoning
The lead poisoning outbreak was caused by artisanal and small-scale gold mining (ASGM). For several months preceding the Zamfara and Niger outbreaks, ore processing was conducted at sites within the villages, including inside homes to utilize women’s labor. Though these communities had been involved in ASGM for generations, the introduction of a new ore exceeding 10% proved fatal. In Zamfara in April 2010, with death and illness prevalent, the local Emirates ordered a temporary suspension of ASGM and later required that all operations be moved outside the villages. However, extremely contaminated soils remained in the residences and communal areas.
In Zamfara, remediation continued through 2013 in three phases, encompassing 8 villages (Dareta, Yargalma, Abare, Tungar Guru, Sunke, Tungar Daji, Duza, and Bagega) and 17,000 residents. The work was conducted by Zamfara State with TIFO providing technical guidance. More information on the Zamfara Response can be found in the journal articles and technical reports below. More than 27,000 cubic meters of contaminated soils and mining waste were removed, 820 residences and public areas were remediated, soil lead exposures decreased by 97%, and average pre-treatment BLLs declined from 173 µg/dL to <20 µg/dL.
Niger State characterization occurred in 2015 and remediation was funded and implemented by the Nigerian government the following year. Two villages (Ungwar Kawo and Ungwar Magiro) with a combined population of 2500 were remediated. In total, 69 homes and 60 communal areas in the two villages were remediated, allowing children to receive life-saving chelation therapy.
The unprecedented outbreak and subsequent response demonstrate that, given sufficient political will and modest investment, the world’s most challenging environmental health crises can be addressed and resolved within the capabilities of host countries.
Journal Articles & Technical Reports
Tirima S, Bartrem C, von Lindern I, von Braun M, et al. 2018. Food contamination as a pathway for lead exposure in children during the 2010-2013 lead poisoning epidemic in Zamfara, Nigeria. Journal of Environmental Science 67:, 260-272.
Bartrem C. 2017. Environmental Health and Risk Assessment: Lead Poisoning, Remediation, and Project Sustainability in Zamfara, Nigeria and Lead-Arsenate Contamination in Washington, USA (PhD). University of Idaho.
Tirima S, Bartrem C, von Lindern I, von Braun M, Lind D, Anka SM, Abdullahi A. 2016. Environmental remediation to address childhood lead poisoning epidemic due to artisanal gold mining in Zamfara, Nigeria. Environmental Health Perspectives 124, 1471–1478.
Tirima S. 2014. Unprecedented lead poisoning outbreak in Zamfara, Nigeria: A multidisciplinary humanitarian response to an environmental public health disaster in a resource scarce setting (PhD). University of Idaho,
Bartrem C, Tirima S, von Lindern I, von Braun M, Worrell MC, Mohammad Anka S, Abdullahi A, Moller G. 2014. Unknown risk: co-exposure to lead and other heavy metals among children living in small-scale mining communities in Zamfara State, Nigeria. International Journal of Environmental Health Research. 24(4), 304-319.
von Lindern I, von Braun M. 2011. Zamfara, Nigeria Lead Poisoning Epidemic Emergency Environmental Response May 2010 - March 2011: a report prepared for UNICEF Programme Cooperation Agreement (PCA Ref: YW-303(01)).