Sure. The legislation does incorporate the precautionary principle right now, but it's just not implementing it. To me, the fundamental anti-precautionary aspect of this legislation is that the burden is on government to prove toxicity, rather than the burden being on industry to prove safety. In fact, for some substances we simply don't have a good dataset, so unlike the European Union which has this principle of “no data, no market”, we don't have that principle currently.
For the substances that were grand-parented and have not undergone in-depth review through the chemical management plan, I characterize it as a “hope for the best” policy. That's what Dr. Thornton is talking about in terms of experimentation. When substances are released that aren't well understood, it's effectively an uncontrolled, involuntary epidemiological experiment.
A precautionary approach actually requires industry to provide data, and for substances of high concern, to provide proof of safety.