EWGs argument is that if a few bulbs can go that low, so can they all. But I'm not losing sleep over whether the CFLs in my house contain enough mercury to cover all of a ballpoint pen tip, or just half of one. For one thing, the power plant pumping out the electricity to power that bulb is releasing way more mercury into our air and water (and fish) than any household could if it broke open its lightbulbs with abandon, and by using lightbulbs that use a quarter of the energy of regular bulbs, you're putting a dent in that. Moreover, the mercury isn't a problem as long as the bulb stays in tact. Should you break one, the EPA lists on its Web site some extremely alarming instructions for how to clean up mercury. (Vacuuming, it seems, is a big no-no). The mercury means these are considered hazardous waste and you should not blithely throw them into your household trash. But Ikea and Home Depot both take bulbs for recycling. Recycling Web site Earth911 can steer you to other local stores and recycling centers that take them. Meanwhile, the EPA keeps a state-by-state list of hazardous waste collection sites. For me, the mercury issue is a lot of unnecessary kerfuffle. In terms of human and environmental health, the far more serious concern is mercury from power plants, industrial processes like metal production and products like car batteries. Moreover, the energy savings makes overwhelming financial and eco sense. If you're among those who still need to be convinced that CFLs are worth the switch, the EWG offers a calculator that shows you how much money you would save by switching to CFLs or halogens, depending on how many bulbs you replace, how many hours a day you use them and where you live.