According to the study, blue light from artificial sources is increasing, which can have negative consequences for human health and the environment in general. From the report: Scientists from the University of Exeter have identified a shift in the lighting technologies that European countries use at night to illuminate streets and buildings. Using images taken by the International Space Station (ISS), they found that the orange emission from old sodium lights is quickly being replaced by the white emission from LEDs. While LED lighting is more energy efficient and costs less, researchers say the increase in blue light associated with it is causing “significant biological impacts” across the continent. The study also claims that previous studies on the effects of light pollution have underestimated the effects of blue light.
Chief among the health effects of blue light is its ability to suppress the production of melatonin, a hormone that regulates sleep patterns in humans and other organisms. Many scientific studies warn that increased exposure to artificial blue light can worsen people’s sleeping habits, which in turn can lead to various chronic diseases over time. The increase in blue light radiation in Europe has also reduced the visibility of stars in the night sky, which the study says “may affect people’s perception of nature”. Blue light can also change the behavior of animals, including bats and butterflies, by changing their movements towards or away from light sources.