A few years ago, you may recall, the Bloomberg administration unveiled what would quickly become a wildly unpopular new streetlight plan, announcing that New York City would be making the switch to longer-lasting, more environmentally friendly LED bulbs. “People tend to like them,” Janette Sadik-Khan, then the city’s transportation commissioner, told the New York Times in 2013. “It’s clear. It’s bright. It really does a good job in providing fresher light.”
Oh. Oh, honey. “Like” seems like kind of a strong word. “Notice” is not incorrect, if you want to put a positive gloss on it, but “despise with the fiery passion of a thousand suns” may be the most accurate. In a Change.org petition prostesting the brightness of the lights, commenters compared them to, among other things, “a bad Walmart parking lot,” “an emergency construction zone,” “a zombie picnic,” “the ‘Close Encounters’ mothership,” and Times Square. This past May, seemingly cowed by a rising tide of 311 complaints and creative metaphors, the city responded by agreeing to swap out some of the detested 78-watt lights with softer, 64-watt bulbs — still LED, but not quite so glaring.
And not a moment too soon, either. Light pollution now has a new enemy in the form of the American Medical Association, which last week rolled out new guidelines for healthy public lighting. The number-one recommendation: Get rid of high-intensity LED lights. Those things aren’t just an annoyance or an eyesore — they’re also a health hazard, and they can mess you up.
One of the most obvious effects, the AMA wrote in a statement about its streetlight report, is on road safety: The glare of LED lights can “decrease visual acuity,” creating more dangerous conditions for drivers. But these bulbs can also influence health in subtler, more long-lasting ways. LEDs give off blue light, a wavelength that disrupts the body’s production of melatonin, a hormone that helps to regulate circadian rhythms; that disruption, over time, can ripple through the body to exacerbate a host of chronic issues.
“It is estimated that white LED lamps have five times greater impact on circadian sleep rhythms than conventional street lamps,” the AMA statement said. “Recent large surveys found that brighter residential nighttime lighting is associated with reduced sleep times, dissatisfaction with sleep quality, excessive sleepiness, impaired daytime functioning and obesity.” Past research has shown, for instance, that out-of-whack circadian rhythms can lead to higher blood-sugar levels and decreased production of the hormone ghrelin, which creates a feeling of fullness. Constant disrupted sleep has been linked to greater risk of depression and heart disease. And as Fast Company has reported, some scientists believe that light pollution may up the risk of certain cancers as well. Hindsight, meanwhile, remains 20/20, especially when you’re looking back through the harsh light of a 78-watt bulb.