Like it or not, energy-sucking, traditional incandescent lightbulbs have been replaced by more efficient, lower wattage (but higher priced) versions and other kinds of energy-efficient bulbs—most commonly compact fluorescent lightbulbs (CFLs).

You’ve probably already tried CFLs in your home. Some people like them…some are indifferent…some dislike the “artificial” quality of the light they emit. That’s just a matter of taste.

But here’s a concern that’s much less subjective. According to a recent study, CFLs can damage human skin and may cause premature aging…impaired wound healing…and possibly even skin cancer!


Before we get into the nitty-gritty of the study, let me explain how CFLs work. The bulbs are coated inside with a phosphor, a substance that absorbs energy and emits light when stimulated by ultraviolet (UV) radiation. The UV radiation is produced when an electrical current—turning on the light—passes through argon-and-mercury vapor inside the bulb. As the phosphor absorbs the UV rays, which are invisible, and re-radiates them outside the bulb in the form of non-UV visible light, the phosphor is also supposed to block the UV rays from escaping. But unfortunately, this doesn’t always happen, the new study revealed.

Led by Miriam Rafailovich, PhD, researchers randomly purchased nine CFLs of differing brands and wattages from various stores in New York. Then they measured the UV emissions from each bulb.

The shocking results: All of the bulbs tested emitted both UVA and UVC rays! (CFLs don’t produce UVB rays.)

Researchers then looked for structural damage to the individual bulbs that would explain how the UV rays could escape and found that every bulb they had purchased had chips or cracks in the supposedly protective phosphor coating. These “bald areas” could be the result of the bulbs’ spiral shape—the curved geometry may put stress on the coating, said Dr. Rafailovich.


Next, researchers wanted to gauge how damaging this type of UV exposure would be to skin. Led by Marcia Simon, PhD, director of the Living Skin Bank, they put a 26-watt CFL bulb (similar in light output to a 100-watt incandescent bulb) in a typical desk lamp. They placed petri dishes containing human skin cells at various distances from the lamp, then compared the level of UV exposure on the skin cells with government guidelines for the maximum radiation intensity that workers can safely be exposed to during an eight-hour span.

Scary findings: When one randomly chosen CFL was tested at 14 inches away from the skin cells (a typical working distance when using a desk lamp), the maximum safety level was reached after only five hours—well before the eight-hour mark. And when the CFL was just one inch away from the skin cells, the maximum safety level was reached in only 79 seconds!

The closer you are to the source of UV rays and the longer you’re exposed to them, the greater your risk for skin damage. By analyzing various changes in the cells in the petri dishes, researchers deduced that UV exposure from CFLs could cause potentially serious problems. I mentioned this earlier, but it bears repeating—the problems researchers cited included premature aging, impaired wound healing and even skin cancer. No such effects were seen when the skin cells were exposed to incandescent light.


As you would expect, after this study came out, the National Electrical Manufacturers Association issued a statement calling the UV-radiation levels from CFLs “acceptably low” and saying that “only under unusual conditions” would someone be exposed to levels above what’s considered safe. But this study showed that “unusual conditions” apparently would include structural damage found in many, if not all, CFLs! Dr. Rafailovich hopes that this study will put pressure on the bulb industry to correct the leakage problem in order to safeguard consumers.

In the meantime, how can you protect yourself? Sure, you could leave the lights off as much as possible—but obviously, when you need light, you need light. So here are some strategies suggested by Dr. Rafailovich…

When a CFL is on, try to stay at least 30 inches away. At that distance, most of the CFLs tested were within the limits considered to be safe.

Use light fixtures that have glass shades. Other lighting-shade materials (fabric, paper, plastic) do not provide any protection against UV rays, whereas glass does absorb some UV rays. How much it absorbs depends on the thickness of the glass, Dr. Rafailovich said—and though the glass on a CFL clearly is too thin, the one-eighth-inch thickness of a typical light fixture shade is probably OK. The shade can be clear glass or colored—it’s the material, not the hue, that matters. But do be aware that with a shade that does not fully enclose the bulb, such as a bowl-shaped shade, some UV rays will not be blocked.