If people are sleepless in Seattle, it may not be only because they have broken hearts.
The American Medical Association issued a warning in June that high-intensity LED streetlights — such as those in Seattle, Los Angeles, New York, Houston and elsewhere — emit unseen blue light that can disturb sleep rhythms and possibly increase the risk of serious health conditions, including cancer and cardiovascular disease.
The AMA also cautioned that those light-emitting-diode lights can impair nighttime driving vision.
Similar concerns have been raised over the past few years, but the AMA report adds credence to the issue and is likely to prompt cities and states to reevaluate the intensity of LED lights they install.
Nearly 13 percent of area/roadway lighting is now LED, according to a report prepared last year for the Department of Energy, and many communities that haven’t yet made the switch plan to do so. LEDs are up to 50 percent more energy-efficient than the yellow-orange high-pressure sodium lights they typically replace. They last for 15 to 20 years, instead of two to five. And unlike sodium lights, the LEDs spread illumination evenly.
Some cities say the health concerns are not convincing enough to override the benefits of the first-generation bright LED lights that they installed in the past three to eight years. New York is one of them, although it has responded to resident complaints by replacing the high-intensity, white LED bulbs with a lower-intensity bulb that the AMA considers safe.
Scott Thomsen, a spokesman for Seattle City Lights, which is responsible for the city’s exterior illumination, dismissed the health concerns about bright-white LED lights, noting that they emit less of the problematic blue wavelengths than most computers and televisions.
After a year and a half of discussion and sampling, Lake Worth, Fla., is replacing its sodium streetlights with about 4,150 LED lights with an amber glow. “We found a color that made sense for the health of our city, and we’re proud of the choice we’ve made,” Michael Bornstein, the city manager, said.
Mark Hartman, Phoenix’s chief sustainability officer, said the city might go with a mix of the intense lights for major intersections and ballpark areas that need very bright light and a softer light for residential areas. He said the city would consider the health arguments, although he too mentioned the glow from computers and televisions. “Nobody says don’t watch television or use your computer after 9 p.m. because of blue lights,” he said.
Almost as soon as outdoor LEDs were made available, the federal government encouraged states and municipalities to use them, calling LEDs highly efficient for applications such as traffic lights and exit signs. But critics say federal authorities were too quick to endorse LEDs.
Read more of the original article at The Washington Post.
