Regarding CFLs and mercury, the concern does seem to be rather exaggerated. I used to work in San Jose, and most days would bike to work along this supposedly mercury-polluted stream:
Los Alamitos Creek - Wikipedia, the free encyclopedia - which supports trees, fish, deer, bobcats, and supposedly (though I never saw one) mountain lions. Used to go hiking around the old mercury mines here:
Almaden Quicksilver County Park - Wikipedia, the free encyclopedia
Now I wouldn't go around claiming that mercury emissions are a good thing, but here and elsewhere, ecosystems seem to deal with it.