So, it turns out No. 7 isn't so lucky after all.

It's a little strange to be rifling through the water bottles in the cupboards here at Casa de Barrett -- chucking any of the ones with a little No. 7 inside the familiar, 3-arrowed recycling triangle into the trash can.

Because, after all, there are complications with recycling these trendy little beauties.

It's obviously disturbing that what we thought was doing such a great job -- carrying a water bottle instead of using up hundreds (literally hundreds) of the tiny little bottles of water we buy at the grocery store -- could have been doing more harm than good. I don't know what "polycarbonate" means, but I know now that when it comes to having it holding my water, it's bad news.

I don't want bisphenol-A (a chemical used to make the plastic) getting into my system. Heck, I don't even like sugar getting into it -- and I'm pretty sure I know what that does.

What does all this have to do with the outdoors? Well, Nalgene mass produces the hip little liter-sized bottles that were supposed to help us live more "green," the ones that hiking, biking, skiing and snowshoe enthusiasts were impulse buying at the counters of their favorite outfitters.

But they're no good now, and I shudder to think that if -- even at room temperature, as studies have suggested -- chemicals are transferring into my water, what happens when they end up in a big pile at the town dump?

Can I drink the town water? Can I eat the fish I catch out of the town pond? Heck, can I take my kids swimming in that pond?

So go and rummage through the house for signs of ol' No. 7 -- you'll be doing yourself a favor.