Radiation emission of compact fluorescent bulbs?

July 8, 2013 4:22 PM

Concerned about radiation exposure from a cfl bulb used in bed headboard reading lamp?

We were on vacation last summer when the results of this reputable study appeared in the media.

When I recently became aware of the study, I immediately replaced the cfl bulb I've had in my headboard reading lamp for the past 18 months or more. I'm a grey-eyed redhead with extremely fair skin. All my life I've avoided the sun. I use sunscreen, wear long sleeves and pants, and I've worn a tightly woven, wide-brimmed sun hat for over twenty years. The cfl bulb I replaced did indeed have a "bald spot" in the phosphor coating, about 3/4 inch long and 1/4 inch wide. There also may be small cracks not visible to the naked eye. The reading lamp, being on the headboard, was only about 9-10 inches away from my head, neck and shoulders.

I've had no reddening of the skin or "sunburn", but naturally, I am concerned about any possible effects of radiation. I will mention the cfl bulb to the dermatologist at my yearly skin scan---which isn't until November.

How worried should I be about this exposure? It's becoming harder to buy incandescent bulbs, as there seems to be a strong push to the cfls. Also, I'm wondering why there hasn't been more media attention given to this reputable study? My children and other family members are also fair-skinned and get sunburned easily if they don't take care.

Thanks to all hive members who have advice and expertise.

posted by ragtimepiano to Science & Nature (10 answers total)

It's becoming harder to buy incandescent bulbs, as there seems to be a strong push to the cfls.

But it's also getting easier to buy LED bulbs which produce better light, consume less electricity, and last longer than CFLs.
posted by RonButNotStupid at 4:40 PM on July 8, 2013 [1 favorite]

Response by poster: Yes, Ron, we have two floor reading lamps with LED.
posted by ragtimepiano at 4:47 PM on July 8, 2013

The NIH says :

But in contrast to media depictions of “skin-frying” CFLs, researchers are reluctant to draw conclusions about consumer risk on the basis of these findings. “The UV measurement procedures are not described, so one cannot evaluate the data,” says Mats-Olof Mattsson, a cell biology professor at the Austrian Institute of Technology. The authors also reported higher UV emissions than other studies have found and did not follow international measurement standards, he adds.

...

UV radiation from CFLs can often, but not always, be avoided by purchasing “double-envelope” bulbs in which the spiral tube is enclosed in a glass or polycarbonate cover resembling a standard incandescent bulb. The U.S. Food and Drug Administration and Health Canada advise that single-envelope CFLs should not be used at distances closer than about one foot.

posted by Pogo_Fuzzybutt at 4:51 PM on July 8, 2013 [1 favorite]

Here is a FAQ from the FDA on the same issue :

The Illuminating Engineering Society of North America (IESNA) has published a series of standards relating to radiation emissions from general purpose lighting. If a CFL were to exceed allowable levels of UV (according to IESNA RP 27.3), its packaging would be required to be labeled with a caution label. This standard, which was developed with the assistance of the FDA, requires lamp manufacturers to provide a suitable caution if one is needed. At typical use distances, UV levels from CFLs fall below the level of general concern for normal, healthy individuals and therefore carry no such warning.

...

However, a recent study from the United Kingdom Health Protection Agency has found that there are measureable levels of UV from single envelope CFLs when used at distances closer than 1 foot. As a precaution, it is recommended that these types of CFLs not be used at distances closer than 1 foot, for more than one hour per day.

posted by Pogo_Fuzzybutt at 4:54 PM on July 8, 2013 [1 favorite]

Seconding LEDs if you are concerned. You can buy them to fit a standard socket, if that's what you have in your reading lamp.

Regarding your query about media attention: Media are not going to give this much attention unless there's some followup that finds significant morbidity, ie., scary skin cancer statistics. (Although the story did get picked up here and there.) That's not the case with this study, which only looked at skin cells in petri dishes and cites anecdotal data from some Israeli kibbutz, as reported in some newspaper. They did not do a controlled study of skin cancer in population A living under CFLs versus population B living under other lighting.
posted by beagle at 5:00 PM on July 8, 2013

There are a couple things in this that make me raise an eyebrow. I'm not sure how bit a communal farm in Israel tends to be, but if their pre-CF rate is as high as the worst US state, they need to have about 3000 people working on the farm to average one case per year.

The fact that they say that incandescent bulbs emit no UV, when, in fact, they are black body radiators and do, in fact, emit some small amount of UV is another WTF moment. IMHO when a scientist tells you something is absolutely pure, get yourself another scientist.

But, yeah, if you are worried, LEDs are the way to go.
posted by Kid Charlemagne at 3:05 AM on July 9, 2013

As an optical engineer, I dislike your word choice of "radiation". ALL lights put out radiation; light is radiation (gamma rays are simply a high-frequency form of light).

What you are worried about is UV exposure. Light intensity drops off as the inverse square of distance, so given the above warnings about being too close to a CFL bulb, if one hour at a time at one foot is a limit, you could safely be 2' away from a CFL for up to four horus, or 9 hours at 3'.

Frankly, you're probably safe at 8 hours and 1', from an undamaged bulb. I've never, ever heard of anyone tanning from a CFL, which is one of your body's defences against UV exposure.
posted by IAmBroom at 5:51 AM on July 10, 2013 [1 favorite]

Response by poster: IAmBroom, I mentioned that the bulb in the reading lamp did have a "bald spot." It was not undamaged. These "bald spots" on the phosphor coating are common, according to the study cited; they occur because of the twisted shape of the bulb and the brittle nature of the coating.
Redheads don't usually tan. I have never had a tan in my life. Fair-skinned people usually go directly to "burn" without passing "tan" on the way.
posted by ragtimepiano at 10:42 PM on July 10, 2013 [1 favorite]

Response by poster: (continued) So, do you think that since I haven't had any reddened skin there hasn't been much UV exposure? If there were significant exposure, there would be signs like tanning, or in my case, burning?
posted by ragtimepiano at 10:57 PM on July 10, 2013

Best answer: OK, good point: more generally, human skin shows visible reaction when damaged by UV. Yours hasn't shown such, so your situation sounds fine.

I missed the 9-10" away part of your post (sorry), but still: if you're having no problems, you're having no problems. UV light isn't like gamma radiation; for the most part it tends to demonstrate its cellular damage pretty quickly.
posted by IAmBroom at 2:15 PM on July 11, 2013 [1 favorite]