1) Incidental ingestion of soil and dust 2) Consumption of food contaminated by soil and dust sources 3) Ingestion of contaminated water 4) Inhalation of contaminated dust.
UNICEF, State of Samfara, Anka Emirate, Terragraphics, Medecins Sans Frontieres, U.S. Center for Disease Control
In March 2010, excess childhood death and illness occurring primarily amongst children under five in Zamfara State, Nigeria, was reported by Médecins Sans Frontières (MSF/Doctors Without Borders) to the state health authorities. Investigations led by the US Centers for Disease Control and Prevention (CDC), in collaboration with Federal and Zamfara State authorities, MSF, Blacksmith Institute and the World Health Organization (WHO), revealed that the outbreak was caused by acute lead poisoning associated with artisanal gold ore processing. More than 400 children under the age of five died, and hundreds more were confirmed to be at risk of death or serious acute and long-term irreversible health effects due to extremely high levels of lead. Of the children tested in two villages, 100% exceeded 10 !g/dL (the international standard maximum for lead in blood), with some levels measuring as high as 700 !g/dL.
The source was massive environmental contamination from the informal processing of lead-rich ore to extract gold. Men brought rock ore to the villages, where the women ground it into fine particles. This process resulted in the extensive dispersal of lead-containing dust throughout the villages, including within family compounds.
Seven villages were initially identified for immediate remediation. Seven more villages were later identified for clean up, including Bagega, which alone was double the size of the first seven. In all villages, including in family homes and compounds, soil lead concentrations exceeded 100,000 ppm, far above the internationally accepted standard of 400 ppm for residential areas. Primary exposure routes for children and adults were:
1) Incidental ingestion of soil and dust
2) Consumption of food contaminated by soil and dust sources
3) Ingestion of contaminated water
4) Inhalation of contaminated dust. Consequently, an estimated 2500 children accumulated life-threatening levels of lead in their blood, with thousands more at risk of permanent brain damage.
In June 2010, Zamfara State and Nigerian Federal health authorities formally requested assistance from WHO, CDC, MSF and the Blacksmith Institute to address this problem. MSF offered chelation therapy, a treatment that removes lead from the body, to children with critical levels of lead. However, in order to prevent recontamination, it was required that treated children not return to a contaminated environment. Environmental assessments indicated that lead exposure could be eliminated by the removal and replacement of topsoil and by thorough cleaning/removal of dust from all interior spaces, homes and compounds.
From June 2010 to March 2011, Blacksmith Institute conducted environmental decontamination in seven villages in collaboration with Terragraphics and local authorities. Local villagers were trained to assist with the clean-up operations, including cleaning of homes. Contaminated soil was removed to secure landfills and replaced with clean soil. In total, seven villages were remediated, including 282 residential compounds, 107 exterior areas and 23 processing ponds, allowing for MSF to provide chelation treatment for more than 1000 children. The project also removed highly contaminated material from 7 ponds that were used to make bricks for compound repairs. In addition, UNICEF and project partners mobilized the communities and established male and female advocacy programs to raise awareness, facilitate remediation and support prevention of recontamination.
Furthermore, the project trained more than 200 Ministry, village and private personnel, building local capacity to conduct remediation activities, and provided guidance and assistance to the State in how to address mineral processing activities.
NIGERIAN LEAD POISONING CRISIS–MUCH ACCOMPLISHED, MORE TO DO
Blacksmith Institute is winding down its cleanup in seven Nigerian villages experiencing the world’s worst recorded lead poisoning epidemic. Thanks to a coalition of organizations, a remediation model now exists for widespread replication by the national government.
In summary, achievements have been extraordinary, even heroic, given such difficult circumstances, but much remains to be done. “We have substantially reduced ongoing exposures for over 8,500 people and Doctors Without Borders provided medical treatment for about 1,000 children five years old and under,” reported Blacksmith President Richard Fuller.
In addition, the project “has built significant local government remediation capacity,” he continued, training more than 200 ministry and local government officials and other personnel, as well as fostered “extraordinary involvement of several hundred villagers in both implementing and sustaining a remedy.”
At the request of the government of Zamfara State, a comprehensive, integrated, medical/public health/environmental response is underway. The plan reduces exposure and provides a safe-mining program addressing longer-term issues and re-occurrence prevention.
This project invloved the coordination of many agencies to achieve success. Significant efforts were undertaken by coalition partners throughout every step, most notably TerraGraphics Environmental Engineering, University of Idaho, Doctors Without Borders, the Nigerian Federal Ministries of Environment and Health, Zamfara State Ministries of Environment and Health, Anka and Bukkuyum Emirates and local governments, UN Children’s Fund, UN Environmetal Program-Office for the Coordination of Humanitarian Affairs, World Health Organization, and the US and Nigerian Centers for Disease Control.
But the problem is not solved. Major contamination can still be found in Bagega and other villages. More funding is needed and more work will have to be done to insure children are safe.
Never before has there been a lead poisoning epidemic of this magnitude anywhere in the world. People were dying every day. On-going exposure and blood lead absorption were higher than any previously recorded in the international literature. There was a universal lack of international experience and cleanup models to address such an emergency. In a word, the situation was “unprecedented.”
Further, affected villages were isolated in a difficult-to-access region of the country with conservative social and religious practices exacerbating exposure and morbidity. Contaminated soils and dusts were the principal sources for exposure in communities where nearly all homes were made of mud, consequently, no relief was available.
“Nevertheless, in just three weeks of collaboration among multiple entities, a remediation protocol was developed and implemented in a manner consistent with village social and technical capabilities,” Fuller said. “Greater than 95 percent reductions in soil lead exposure were achieved,” he continued, “and treatment initiated for more than 1,000 children and several hundred families in both clinical and out-patient facilities.
“In accomplishing these ends, tremendous health, environmental, technical, engineering, cultural, capacity, political, logistical, safety, funding and implementation challenges were met,” Fuller summed up. “Now we have to work to insure the rest of the cleanup can be done, but with local leadership,” he added.
A total of 282 residential compounds, 107 exterior areas, and 23 processing ponds have been remediated in five villages. In Bagega, a large landfill has been constructed and prepared for contaminated soils and industrial waste; residential areas, village exteriors, brick-making ponds, and the Bagega industrial site have been assessed; and preliminary design and cost estimates prepared.
Highly contaminated materials from seven ponds in Yarlgama and Dareta–used to make bricks for compound repairs after a particularly damaging rainy season–have been removed.
Male and female advocacy programs have been established to facilitate remediation and support prevention of recontamination, among other community response activities. Villagers are increasingly aware of the dangers of artisanal mining and measures required to protect their families.
The capacity of Zamfara state and local level government to undertake future cleanup has been developed with over 200 ministry, local village, and private personnel trained in appropriate technology. And the international partnership has provided assistance to a new state