It's tragic that so much of our life in the first world depends on these kinds of situations.

I wouldn't blame the materials though, it's really a problem of allowing corporations to treat people badly in the name of mining those materials (or building the product.)

You could also go into a lot of the issues with some of the rare earth metals used in the circuit boards and processors. Since they are so rare/valuable they are often recycled... which sounds great, but it's done by kids in China by hand which leaves a lot of toxic material in their environment. Maybe you were planning on that for part 4 though...