BY TIMOTHY A. SCHULER
The coming conflict between two separate environmental issues.
From the July 2015 issue of Landscape Architecture Magazine.
Correction appended March 2, 2015.
People often equate energy efficiency with environmental sensitivity, but a recent trend in LED lighting, namely, the uptick in what’s known as blue-rich white light, has the potential to divorce these goals and put the lighting industry on a collision course with those aiming to design healthful public spaces.
Over the past several years, an increasing number of LED manufacturers are turning to blue-emitting diodes, which are coated with phosphor to produce a clean, white light. Blue LEDs can handle higher-than-average power densities, which greatly increase efficiency. The technology is so revolutionary that the physicists who developed it received the Nobel Prize. But blue LEDs also pose a threat to the welfare of wildlife and human beings.
Light in the blue spectrum (between 460 and 480 nanometers) isn’t bad during the day; in fact, it helps our bodies produce the hormone serotonin. At night, however, it prevents our bodies from producing another hormone, melatonin, which regulates sleep. According to the National Cancer Institute, a lack of melatonin may contribute to breast cancer in women. Blue light also has been shown to disrupt animals’ circadian rhythms, which mimic our own, and cause adverse effects in animal behavior. (more…)
