In June 2010 Médecins Sans Frontières (MSF) started treating 50 children with serious symptoms of lead poisoning in several villages in the northern Nigerian state of Zamfara. Investigations established that the poisoning was caused by the method of artisanal gold mining practised by the villagers. This involved crushing and drying the ore containing the gold in the open air, leading to huge quantities of lead-containing dust being released into the soil and groundwater.

Scale of incident

MSF started working in seven villages in the affected area. There, some 10,000 people, including an estimated 2,000 children under five years old, were suffering from lead poisoning. The disaster was judged to be the worst heavy metal contamination incident on record worldwide. A level of 500 to 700 micrograms of lead per decilitre of blood was measured in some of the children, whereas a level of 100 micrograms per decilitre leads to significant risk of neurological and brain damage in children.

Threat to young children

Lead poisoning is most dangerous for very young children, given their low bodyweight and the fact that they are at a crucial phase of development for their bodies and brains. Lead poisoning can lead to loss of appetite, anemia, weakness and kidney failure. In an advanced stage, reduced consciousness and convulsions are possible, eventually followed by death.

Treatment

Together with the local authorities, MSF set up a treatment centre at a safe distance from the contaminated area. Treatment for lead poisoning of this severity and on this scale in such a remote setting is new, so we sought the support of an international network of toxicologists in addressing the situation. The only treatment available was chelation therapy. In this method, the medication binds to the lead in the bloodstream, after which it is excreted in the urine. Chelation therapy can only remove the lead from the blood, while the body also accumulates lead in the bones, teeth, etc. This accumulated lead is slowly released into the bloodstream, which means that the chelation therapy needs to be repeated several times until a physiologically safe blood lead level is achieved. Each round of therapy takes 19 days. By the end of 2010, our team was treating 900 children from the seven villages.

Cleaning contaminated soil

The medical treatment for lead poisoning will be made ineffective as long as exposure continues either through the contaminated environment or through ongoing unsafe mining activities. So in June 2010 the environmental firm TerraGraphics Environmental Engineering and the international nongovernmental organization the Blacksmith Institute, in cooperation with the local authorities, started cleaning the soil of the affected villages. A program to teach safe mining practices was also introduced.

Lobbying

In 2010, MSF started to lobby the Nigerian authorities and international organizations such as the United Nations and the World Health Organization to identify the extent of the problem and commit to resolving it over an extended period of time. While they are the most vulnerable, treating the young children is only the most urgent part of the entire emergency: older children and adults are also in need of treatment. A complicating factor is the cost of the treatment. One round of treatment for a young child costs approximately $425. For older children and adults, higher dosages are required.