Nigeria's lead poisoning crisis could leave a long legacy

Abstract

Zamfara state in northwest Nigeria is in the midst of what Human Rights Watch (HRW) describes as the “worst lead poisoning epidemic in modern history”. 400 children have already died, and experts fear that the situation could easily deteriorate. In early 2010, Medecins Sans Frontieres (MSF) were called into the village of Yargalma. There, they discovered that large numbers of children had died and others were experiencing seizures. The international level-of-concern for lead poisoning is defi ned as 10 μg/dL of blood. Samples taken from Zamfara showed levels as high as 900 μg/dL. Lead is highly toxic. It aff ects the body’s neurological, biological, and cognitive functions. Children are exceptionally vulnerable: if an adult ingests lead, around 10% is absorbed; children absorb roughly half the lead they ingest. It damages the brain, liver, kidneys, nerves, and stomach as well causing irreversible intellectual and developmental disabilities. But it does not kill unless present in enormous quantities. Yet in 2010 villages in Zamfara saw child mortality rates of 40%. Today, Bagega—population 10 000—has lead readings of 78 000 parts per million (ppm). The safe level is under 400 ppm. The cause is mining. Zamfara has been the scene of artisanal gold mining for decades. Individual miners—sometimes children—rig up unsupported shafts, smash rocks with hammers, and mill the ore, sometimes at home, sometimes on site. Essentially subsistence mining, it exists in a legal grey area. Activity used to be sporadic, but a few years ago the value of gold started to spike. It prompted a gold rush. By 2009, Zamfara’s artisanal miners had hit upon a vein of gold heavily contaminated with lead. Miners would return home covered in lead-contaminated dust. The prevalent milling process—dry milling intended for grain—exacerbates the problem, throwing up thick clouds of dust. Lead contaminates food and water supplies and building materials. A primary pathway is soil, and children, especially those that are crawling, are near the ground.