Checkup: UV Light Kills Germs
Iíve spent a fair amount of my life trying to destroy the bacteria and viruses in my environment. I canít see them, but I can feel them. So I was delighted to recently find a battery-powered germ-killing gadget in the pharmacy. Itís an ultraviolet light the size of a cell phone. The idea is that you can flip it open and wave it over keyboards, phones, and shopping-cart handles to kill the germs on them.
Frankly, it looked too good to be true, especially when discounted from $14 to $3. I called Anne Maczulak, the author of The 5-Second Rule and Other Myths About Germs, to break the inevitable bad news.
So, I asked her: does UV light really kill germs?
"It does, absolutely. Itís been used for many years. Itís very effective in killing germs under certain circumstances. Water treatment plants that produce your drinking water use UV lights more and more, theyíre trying to get away from chlorine and some of the chemicals and they are trying to go toward less-invasive things like UV light."
But the light on this little gadget looks pretty feeble. Is it actually doing anything?
"It probably can damage some of the bacteria; it affects viruses, fungal spores. Itís pretty wide-ranging, so it has some activity. Hereís the thing thatís a bit of a caveat. Usually you have to hold it in place for at least 2 minutes to really be assured that youíre killing germs in the very spot youíre focusing on. Unfortunately, just waving it over the surface of the keyboard or countertop may not be sufficient."
As I was waving this thing over my desk, I could almost hear the cries of entire civilizations of germs dying in mass extinction. Apparently, though, they were just taunting me.
Youíve spent years finding ways to kill germs. Do you ever feel, you know, guilty about it?
"Bacteria have been here long before we have, and theyíll be here long after we leave the planet, so Iím not too worried about them."
Iím Eric Metcalf, keeping my eye out for a bleach-powered flamethrower.