A couple of years ago, and with great zeal, I replaced the incandescent (IC) bulbs in my home with CFLs, touted as superior in terms of energy savings and thus, I naively thought, superior in terms of environmental sustainability. I knew that CFLs should be recycled rather than tossed in the garbage, but I thought I wouldn’t have to worry for at least five year, their alleged lifespan. So I was surprised when my bedside reading lamp bulb died a few days ago, sooner than my older ICs.

There I stood, peeved in the dark.

GE claims that CFLs last “10 times longer than a 100 watt regular soft white bulb.” The fine print adds that the bulbs are “Guaranteed to last 5 years based on 4 hours use per day at 120V.” So why did my bulb die? I found out that frequently turning a CFL on and off shortens its life. Energy Star recommends leaving the bulb on for at least fifteen minutes to assure its longevity. (Am I missing something? Weren’t we were supposed to save energy?)

Trying to look on the bright side, I realize that my bulb is under warranty. I’ve never kept it on four hours a day, since I usually fall asleep after 15 minutes of reading. If I want a replacement bulb, I have to provide proof of purchase (like the UPC code from the original package) and my register receipt. Sorry, I don’t have a receipt or packaging for something I bought two years ago. Even if I did, I’d have to protect the bulb with lots of packing material, buy a small box, pay postage—all of which would cost more than a new bulb.

How to safely dispose of the defunct CFL became the question. Waste Management sells a recycling kit for $19.95, which includes a prepaid return shipping label for up to 13 bulbs (www.wm.com/residential/recycle-by-mail.jsp). But Home Depot takes back CFLs one at a time. I drop the bulb off there, hoping that it will indeed be safely recycled.

Luckily I didn’t throw the bulb in a fit of pique. Each CFL contains five milligrams of mercury sealed within the bulb’s glass tubing. Once the tubing breaks, the mercury is released as mercury vapor. EPA recommends precautions when cleaning up a broken CFL, which can be found at www.epa.gov/cfl/cflcleanup.html, including evacuating people and pets from the room and airing it out for 5-10 minutes.

It is estimated that between 600 and 670 million CFLs end up in U.S. landfills each year, releasing two to four tons of mercury into the atmosphere, almost half the amount emitted by coal-fired power plants. Popular Mechanics crunched the numbers (popularmechanics.com/home/reviews/news/4217864) and concludes that, despite those figures, CFLs still contribute less to mercury emissions than ICs in their over-all life cycle.

Not very encouraging, considering the impacts of mercury pollution on our air, water and food. Nevertheless, Congress passed legislation that will phase out IC bulbs completely by 2014, except for certain high and low wattage bulbs.