How Much Mercury is in a CFL Bulb?

Mercury is a scary substance. From vaccines and seafood to thermometers and industrial waste, mercury has been blamed-- fairly in some cases, and unfairly in others-- for problems ranging from psychosis to autism. Because of this, almost any health-savvy person will bristle when they hear the word. Fear of mercury has even stemmed a wave of backlash against energy-efficient compact fluorescent (CFL) lightbulbs.

Make no mistake-- mercury is poisonous. But it's not a reason to stop using CFLs. On the contrary, the energy consumption posed by incandescent bulbs poses a significant health risk to the world at large. Incandescents are responsible for massive amounts of air pollution, including the heavy metals produced as a by-product of the petroleum industry.

But just how much mercury is in a CFL? And is is it enough to worry?

An ordinary CFL lightbulb contains about 4 milligrams of mercury. If you were directly exposed to this amount from a broken bulb, it is plausible that it could cause health problems, especially if you are pregnant. However, to put this in perspective, let's look at a few other sources of mercury-- which you may need to be more concerned about.

An old-fashioned mercury thermometer contains about 500 milligrams of mercury. That's almost 150 times the amount found in a CFL bulb. These thermometers are obsolete for a reason-- they did cause many life-threatening illnesses-- but it's important to remember that they were used for centuries and contain far more mercury than a CFL bulb.

Some types of fish meat also contain substantially higher levels of mercury than can be considered safe. For example, bluefin tuna contains a whopping 1.3 milligrams of mercury per pound. And, unlike the mercury inside a CFL bulb, the amount of mercury in seafood goes directly into your body, where it can quickly begin harming your central nervous system if you consume too much.

Pollution in the air and water around you can also increase levels of mercury in your bloodstream. In heavily polluted areas, some people inhale several milligrams of mercury every year. This is far from healthy, but a much more realistic fear than accidental exposure to mercury from broken CFL bulbs.

The bottom line? There is some mercury in a CFL bulb, and it is enough to be concerned if you break a bulb. But, if you handle these energy-efficient bulbs carefully, your risk is pretty minimal compared to your risk of mercury poisoning from other sources.