It was good to see the LightAware charity highlighting the particular problem of blue-rich LEDs in the discussion on the rise in light pollution (Letters, 7 November). I loved Jacqueline Yallop’s rich and vivid article (Everything from our sleep to our hormones relies on the dark. So why are we so intent on destroying it?, 31 October), but felt it missed this important point: it is not just the quantity of light that has changed in recent decades, but the quality of that light.

The hasty switch to LED lighting led to a poorly executed project: local governments across the UK installed lights in public structures and areas, as well as on our streets, that emitted excessive and intense blue light. This particular wavelength of light is known to significantly disrupt the circadian rhythm, affecting not just sleep but also other bodily functions in humans and the environment.

A research conducted by Dark Sky International summarizes the current scientific findings on light pollution. It raises doubts about the actual environmental advantages of switching to LED street lights and criticizes it as a form of “greenwashing”. The detrimental effects on human health and overall well-being are unquestionable, with light-sensitive individuals being severely affected and natural ecosystems being disrupted. Additionally, the use of blue light has worsened light pollution by scattering and creating more “sky glow”, which is the hazy layer of artificial light that obstructs the view of stars.

The use of blue-rich LEDs has resulted in a less aesthetically pleasing environment, altering the warm, soft orange hue of our urban areas to a harsh and dismal glare. Light serves not only to brighten our surroundings, but also shapes our perception of the world and influences our lives in significant and nuanced ways. Therefore, we must exercise caution and responsibility when utilizing light.
Anna Levin

The creator of the book “Incandescent” believes that it is important for us to have a conversation about light.

Source: theguardian.com