Background:From 2010 through 2013, integrated health and environmental responses addressed an unprecedented epidemic lead poisoning in Zamfara State, northern Nigeria. Artisanal gold mining caused widespread contamination resulting in the deaths of > 400 children. Socioeconomic, logistic, and security challenges required remediation and medical protocols within the context of local resources, labor practices, and cultural traditions.Objectives:Our aim was to implement emergency environmental remediation to abate exposures to 17,000 lead poisoned villagers, to facilitate chelation treatment of children ≤ 5 years old, and to establish local technical capacity and lead health advocacy programs to prevent future disasters.Methods:U.S. hazardous waste removal protocols were modified to accommodate local agricultural practices. Remediation was conducted over 4 years in three phases, progressing from an emergency response by international personnel to comprehensive cleanup funded and accomplished by the Nigerian government.Results:More than 27,000 m3 of contaminated soils and mining waste were removed from 820 residences and ore processing areas in eight villages, largely by hand labor, and disposed in constructed landfills. Excavated areas were capped with clean soils (≤ 25 mg/kg lead), decreasing soil lead concentrations by 89%, and 2,349 children received chelation treatment. Pre-chelation geometric mean blood lead levels for children ≤ 5 years old decreased from 149 μg/dL to 15 μg/dL over the 4-year remedial program.Conclusions:The unprecedented outbreak and response demonstrate that, given sufficient political will and modest investment, the world’s most challenging environmental health crises can be addressed by adapting proven response protocols to the capabilities of host countries.Citation: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. Environ Health Perspect 124:1471–1478; http://dx.doi.org/10.1289/ehp.1510145

The lead poisoning crisis in Zamfara State, Northern Nigeria has been called the worst such case in modern history and it presents unique challenges for risk assessment and management of co-exposure to multiple heavy metals. More than 400 children have died in Zamfara as a result of ongoing lead intoxication since early in 2010. A review of the common toxic endpoints of the major heavy metals advances analysis of co-exposures and their common pathologies. Environmental contamination in Bagega village, examined by X-ray fluorescence of soils, includes lead, mercury, cadmium, arsenic and manganese. Co-exposure risk is explored by scoring common toxic endpoints and hazard indices to calculate a common pathology hazard risk ranking of Pb > As > Hg >> Cd > Mn. Zamfara presents an extreme picture of both lead and multiple heavy metal mortality and morbidity, but similar situations have become increasingly prevalent worldwide.

No abstract

This research work is aimed at determining the chemical speciation of metals Zn, Mn, Fe and Pb in soil samples from three major dumpsites within Gombe metropolis, Gombe state. The renowned five steps Tessier sequential extraction method was employed in the extraction of the heavy metals. The metals were extracted into five fractions namely: Exchangeable (F1), carbonate bound (F2), Fe-Mn oxide bound (F3), Bound to organic matter (F4) and the residual fraction (F5) in order of decreasing mobility. The elemental analysis of the fractions was carried out using atomic absorption spectrometric technique. The results showed Zn was predominantly bounded to the exchangeable fraction with 32.66±0.31 mg/kg (54.18%) and least in the Fe – Mn oxide fraction with 0.01±0.00 mg/kg (0.02%). The trend in its abundance is in the order F1> F2>F5>F4>F3. Mn was predominantly associated with the bound to carbonates fraction with the value of 103.3.±3.30 mg/kg (56.14%) and least in the exchangeable with the value of 1.30±1.85mg/kg (2.13%) its occurred in the order F2>F3>F4>F5>F1. The concentration of Fe was highest in the residual fraction with the value of 25.90±1.75mg/kg (45.45%)and least in the carbonate bound fraction wi th 5.10±0.40 mg/kg (2.13%) the order is F5>F4>F3>F2>F1. Pb was not detected in most of the fraction but highest in bond to carbonate and bond to organic matter fraction with the values of 6.64±4.12 mg/Kg (70.64 %) and 2.76±0.10 mg/Kg (29.36 %) respectively in two different samples. It was however established that Zn, Mn and Pb were mostly associated with the first three fractions thus, showed high bio-availabilty whereas Fe was found in the residual fraction and is expected to be low in mobility and less bioavailable.