It's heavy metals, and dioxins and furans, and so on that you can't detect, that you can't get out of that burning stream, that incineration stream. Above all, no matter what we do and whatever method we end up with, we must sort at the front end. Wherever it's financially feasible to take a plastic and turn it into something of value, we should do it. Metal, whatever, we should always sort fully. The new technologies that are coming forward are going to make that a lot easier. You need to sort it at the front end and recycle where you can, but there's always going to be something left, and that something that's left is what's dangerous and what we need to be able to refine.
On December 3rd, 2014. See this statement in context.