>It's really easy to sit and demand evidence before regulating something. But consider that if we waited for hard evidence to accumulate before banning lead in gasoline, we likely never would have banned it because the hard evidence wouldn't exist.

We already knew lead was toxic before we started putting it in gasoline. Even the guy that invented it got sick from exposure and people died from exposure in their plants in the first years of operation. The problem is that we somehow require evidence that something is unsafe but don't require any evidence that its safe in the first place.