So you get arsenic out of the water and have coal dust in the air....
Coal dust? COAL DUST?!?
Where in the world did THAT non-sequitir come from???
I like discussing things with you, Ad, as in general you tend to address the issues (and occasionally enlighten me in the process). I agree that there is a concept of "good enough", and that the concept should..no, must be considered in such things as toxicity and its concomittant eradication. But try to stay on-topic, OK? Yes, I know it's easy to get swept up in missionary zeal (like your friend Be occasionally does). But this group is generally intelligent enough to recognize a Red Herring when it sees one (and I'm not talking about the magazine, either ;-) ), and inserting one into your argument reduces it to the level of dismissable blather.