Mercury in CFL's

Q. I keep hearing how great CFLs are for the environment, but then I hear that they contain mercury? Is the energy they save really worth the risk of putting more mercury into the environment? –Charlie, IL 

A. Compact fluorescent light bulbs do contain a small amount of mercury. About four milligrams, to be exact, but don’t rush to return those new bulbs you just picked up at the store. Four milligrams is only just about enough mercury to coat the tip of a ballpoint pen, and a fraction of the roughly 500 milligrams contained in an old-fashioned thermometer. And the lion’s share of mercury sneaking its way into our soil and water comes not from CFL’s or even thermometers, but from coal-fired power plants. So when you consider the amount of mercury that coal-fired plants release as they send electricity to your wall socket, those CFL’s start to look pretty harmless. In fact, CFLs are so much more energy efficient than old-fashioned incandescents that making the switch will, even when you take those 4 milligrams into account, still reduce your overall mercury emissions by 72  percent, according the EPA. And that’s if your burned out CFL gets sent to the landfill, which it doesn’t need to. It’s easier than ever these days to further reduce your mercury pollution by recycling used CFLs; Home Depot stores are collecting them at no charge. So go forth and replace all your incandescent bulbs. There’s really no downside to consider.

-         Sarah Schmidt

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The EPA has a handout ( that treats broken CFLs like an immediate health-threatening emergency. Is this justified?

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