We've known for some time that energy saving bulbs contain mercury; it's essential to how they produce light. However, the manufacturers have previously explained that the energy saved results in less mercury output from power stations. This saving is more than enough to offset the problem, so it was a step in the right direction.
But some of the mercury emitted from landfills is in the form of vaporous methyl-mercury, which can get into the food chain more readily than inorganic elemental mercury released directly from a broken bulb or even coal-fired power plants, according to government scientist Steve Lindberg.
The mercury content in the average CFL -- now about 5 milligrams -- would fit on the tip of a ballpoint pen, according to the U.S. Environmental Protection Agency, and manufacturers have committed to cap the amount in most CFLs to 5 milligrams or 6 milligrams per bulb.
The majority of Philips Lighting's bulbs contain less than 3 milligrams, and some have as little as 1.23 milligrams, said spokesman Steve Goldmacher.
To prevent mercury from getting into landfills, the EPA, CFL makers and various organizations advocate recycling.
Just as with the bio-fuel debate, this is a case where you really have to get informed and weigh up both sides of the argument. Yes, these bulbs save energy, but they may be a larger source of mercury pollution in effective terms, if not in mass.
LED lighting may be a better alternative, and it's slowly becoming available to average consumers. The choice is obviously yours, but whatever you choose to light your home, be informed. [And dispose of your CFL bulbs properly! I'm sure a system could be implemented where you'd get a deposit back when you bring back your old CFLs. It works for beer bottles... -Ed.]