Interesting, I can imagine all of the "pro" pressure treated lumber folks turning a blind eye to the subject of the environmental effects of the treated lumber that we all love. I admit that I use it regularly, but the current restrictions of the applications have limited my use considerably. One application of treated wood is around overhead garage door frames. The bottom of the frame is right down on the ground (garage floor) and nothing looks better than aluminum wrapped over it. I've been covering the wood with black paper and using stainless trim nails. I don't really know if this is enough protection for the aluminum, but at least it's something.
The big issue for me is children's playground equipment. Non-treated wood seems to be a safety issue because of the joints rotting out when non-treated wood is used. When two pieces of wood are attached flat together outdoors, moisture is almost always present. Pressure treated seems to do well in this situation where non-treated seems to break down quickly and you can't see the damage until something fails. Most schools and parks have gone on to steel and composites for playground materials. Maybe this expensive equipment is the way to go. My kids will probably see some treated lumber on tree houses and decks somewhere else if not here at home. So, until something else comes along, is available and affordable, I'm betting that pressure treated will be around for a long time. Pressure treated lumber,, the next big deal, like asbestos, if Ralph Nader was still in his prime,,,,
Tom in KY, With asbestos siding behind my brick and pressure treated lumber scattered around here and there and everywhere around my home.