I can't speak for Mr. Urbonas as to what he meant by no safe level of pollution. I do know that his statement is valid for many types of pollution, but like all unqualified statements (such as this one?
" /> ), there are going to be exceptions. Being invalid for select cases doesn't mean invalid for all cases.
My real point is that there is some measure of truth in all sides of the issue. I'm not close enough to the D&S issue to give any advice, but my experience has (almost) always been (and I deal with a few "hard core" types on both sides of the fence) that acknowledging those truths and looking for middle ground works better than drawing the proverbial line in the sand.
andy