Given the toxicity of mercury, why would light-bulb manufacturers have chosen to use it in the CFL light bulbs that replaced incandescents?
It’s kind of funny how things we didn’t even know enough to worry about a few years ago now have us donning Hazmat suits.
So let me ask you this: Do you have any of those long fluorescent light tubes in your house? Did you know there’s mercury in those things – possibly two or three times more than in these newer bulbs? Have you ever worried about it before? Probably not.
Compact fluorescent lights, or CFLs, are simply those old-fashioned tubes repackaged for a new purpose – to replace inefficient incandescents while saving energy. They work the same way: Instead of electricity heating up a wire that glows, the current in fluorescents is driven through a tube containing argon and a tiny bit of mercury vapor. This generates invisible ultraviolet light, which, in turn, excites a coating (phosphor) on the inside of the tube, which produces the light we see.
As for the mercury, you just can’t make fluorescent bulb without it, the experts say.
“At present, it is scientifically and technically impossible to produce mercury-free compact fluorescent lamps,” according to a report by Europe’s Scientific Committee on Health and Scientific Risks. “But new technologies can reduce the amount of mercury contained, and the authorized content will be gradually lowered.”
According to a 2008 article in Environmental Health Perspectives, CFLs typically contain from 3 to 5 milligrams of mercury. Moreover, a 2011 study found that if you break one, only a tiny fraction of that mercury will escape even if you don’t clean it up for 24 hours. As a result, these researchers found it could take weeks for the levels of mercury vapor in the room to reach a point that might be hazardous to a child.