How to recycle compact fluorescent bulbs
The trace of mercury in CFLs carries some environmental concern. Here are tips on what to do when it’s time to toss them.

By Jennifer Openshaw, MarketWatch

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Green is good. Buy CFLs to replace your traditional incandescent bulbs. Lots of people are doing it; about 80 million to 100 million CFL bulbs are already in use. And countries such as Australia and companies such as Philips have vowed to make us "incandescent-free" in four to eight years.

You see, 90% of the energy consumed by traditional incandescent bulbs becomes heat, not light. So a CFL saves roughly 80% of the energy consumed by those traditional bulbs.

And that's a lot, taken on a national or global scale. The Washington-based Earth Policy Institute estimates that a complete switch to CFLs in the U.S. could eliminate 80 coal-fired generating plants. A worldwide shift would expand that number to 270.

But here's the problem: CFLs -- like all fluorescent lamps -- contain a small amount of mercury, a persistent poison that can be water- or airborne and cause nerve damage. It is indeed a small amount -- 5 milligrams -- about one-hundredth of that contained in an amalgam dental filling. But multiplied by the numbers out there, it's significant.