Each plastic part is sorted by heating it with a cigarette lighter. From the fumes workers can tell exactly what kind of plastic they're holding. Every year Guiyu takes in more than a million tons of computer waste, imported from all over the world. About 40,000 local farmers and 100,000 migrant workers make their living from the e-waste, which contains toxic ingredients such as lead, beryllium and mercury. The workers risk catching respiratory and skin diseases, eye infections and even cancer..