Kabwe, Zambia, might be Africa's most toxic city. A century of lead and zinc mining that began at the dawn of the 20th century is responsible for the sickening of more than a third of this bustling city of 220,000 inhabitants. The mines have been closed for decades, but the latent contamination from millions of tons of tailings that permeate the streets and neighborhood of Kabwe are poisoning a new generation of Zambians. Time is the enemy as international NGOs and aid groups struggle to mitigate the ongoing pollution. Medical researchers estimate many of Kabwe's residents have blood lead levels up to 10 times internationally recommend threshold levels. Many of these victims are children.