Terrible news out of Nigeria. The UN confirmed reports from NGOs and local activists that at least 400 children have died from lead poisoning since March in one Nigerian province. What happened is this: communities have long maintained backyard, informal (and illegal) gold digging operations in Nigeria’s Zamfara state. In at least two villages, the gold digging sites were heavily contaminated with lead. Medicins sans Frontier noticed a spike in lead illness earlier this year, but the affected communities had powerful economic incentives to keep up the gold extraction. From IRIN: The trade is profitable: it takes about two hours to extract about one gram of gold, which miners can sell for US$23. In comparison, 50 kg of millet, which takes four months to cultivate, sells for $40, said Umaru Na-Ta’ala, who lives in Kirsa village, where 50 children have died and there have been 20 stillbirths since 2010. In addition to lead poisoning, mercury levels are extraordinarily high: At one former mine processing site in the village of Bagega, with some 8,000 inhabitants, air mercury levels of 5,000 nanogrammes per cubic metre were registered, a hundred times the maximum recommended level of 50. Mercury, which is used in the gold extraction processes, affects the nervous and digestive systems when inhaled. The World Health Organization is expected to release a report of their findings later this month. In the meantime, this is just one more testament to how economic depravity seems to always hit children the hardest.