Don’t Sit Near CFL Bulbs

Ah, progress… now that thousands of us have diligently exchanged our traditional incandescent light bulbs for the new, energy-efficient compact fluorescent light bulb (CFL) kind, we learn that they can be risky if you sit very close to them. Invented in the 1970s, CFLs came to market about 100 years after conventional incandescent light bulbs. They’re growing more popular today since they use about one-quarter the energy of equally bright incandescent bulbs, last up to nine years and are cost effective.

But they’re not exactly a perfect solution. We’ve since learned that CFLs contain trace amounts of mercury (though less than 1/100th of that in those old-fashioned thermometers) and should be disposed of in mercury recycling facilities (Home Depot now offers CFL recycling in its stores). Now we need to add sunburn — or something very much like it — to the list of possible associated harms as well. Research from the United Kingdom’s Health Protection Agency (HPA) shows that certain CFLs can emit ultraviolet radiation higher than international guideline levels. In excess, this can damage skin.

For details, I contacted John O’Hagan, PhD, group leader of HPA’s Laser & Optical Radiation Dosimetry Group. He told me that photosensitive individuals (people who have an accentuated dermatological response to light, especially sunlight) reported suffering adverse health effects after replacing incandescent light bulbs with CFLs, which led his group to undertake a study of lamp emissions. The measurement revealed there was indeed a potential danger, though it is small and limited to certain people under certain conditions. “It was only after we had completed these measurements that we realized that the ultraviolet radiation emissions could exceed internationally agreed-upon exposure limits at close range,” Dr. O’Hagan said.

Before you get alarmed, be aware that CFLs that look like traditional light bulbs (“encapsulated”) and long-tube fluorescent ceiling lights are not considered a problem. But the study found that some of the “open” CFLs — spiral shapes, for example — do emit significant ultraviolet rays, which could be a problem for those who work in close proximity to them. Photosensitive individuals who spend significant time close to these bulbs — for instance, if they are used in a desk lamp — can experience ultraviolet skin exposure equivalent to direct summer sunlight at midday. This can cause a reddening of exposed skin, and since there is a wide range of photosensitivity among individuals, there is in fact potential for a serious reaction. Also, as with direct sunlight, the additional exposure boosts risk of skin cancer in some photosensitive people.

However, when you are more than 12 inches away, the ultraviolet level is much lower and not of concern. Dr. O’Hagan advises not using these open CFLs in any situation where you’ll be sitting a foot or closer to a bare bulb, but beyond that sees no need to stop using these energy-saving lightbulbs in our homes. He also notes that it is possible to manufacture these bulbs in such a way that eliminates this risk, as evidenced by the fact that 80% of them are safe. So, we can hope that the less safe ones will soon go away altogether now that the risks are known.