Abstract
Abstract
In modern times we are exposing ourselves to artificial light sources more than our ancestors were and it is conflicting with learned behaviours developed during the evolutionary process over thousands of years. In this review paper, the effect of this rapid change and possible effects on human wellbeing is questioned. Publications detailing, the health consequences of circadian disruptions and the current stage of global artificial light at night publications have been reviewed to see the level of intrusive lighting at night and to understand the possible connection. The current level of light pollution is mainly questioned as it is reported that the human circadian system and melatonin suppression is more sensitive to a lower level of light than has been previously reported [1]. During the time of review “Light at Night and Circadian” terms used in at Google Chrome search engine and, 24,557 publications were found on Science Direct [2], 17,500 publications were found on Google Scholar [3], and 1,240 free publications were found on PubMed [4] sites that are directly related to the circadian rhythm and light at night topics. Among those publications, recently published research papers (2010-2020) have been selected for review to narrow down the reviewed light sources to light emitting diodes (LEDs) as it is noted that the circadian system is susceptible to the blue wavelengths and LEDs are showing a peak in their spectrum at the same sensitivity area. At the end of the review, possible direct connections between the use of artificial light and adverse physiological and psychological effects with more severe health problems have been found. In addition, the current light pollution studies showed that vast majority of the global population is living under light polluted skies and possibly experiencing the negative effects of disrupted circadian system daily and therefore experiencing deteriorating effects of circadian disruptions and personal wellbeing. As the use of artificial light rapidly increases with global population, exposure to artificial light will increase exponentially in the near future and not only human beings but also the rest of the ecosystem will suffer from its negative effects. Because of this rapid change we should start implementing more stringent guidelines written with consideration for the health implications of artificial light while controlling the excessive use of it. Also, as the LED based lighting systems increase their popularity worldwide, we should start researching a possible modification to reduce the impact of the LED lighting on circadian system and its negative effects on human wellbeing.