Night shift work – does it mean light pollution as well?

Abstract

Light pollution denotes an excessive presence of the artificial lighting, particularly at night (ALAN). Since the electricity introduction people started to be active all-round the 24-hs period. However, human physiology is adapted to the regular sequence day/night with the activity during the day and the nocturnal relax and sleep. Diurnal organization of the physiological processes is controlled and synchronized by the endogenous molecular mechanism known as a biological clock with a master structure located within the hypothalamic suprachiasmatic nuclei (SCN). Information about the external lighting conditions is relayed from the special retinal receptors via SCN to the pineal gland synthesizing melatonin, a hormone of darkness. ALAN from various sources, including night shift work and/or electronic devices, evokes misalignment of the endogenous clock and physiology desynchronization. These circumstances are resulting in several civilization-related illnesses, including some cancer types, depression, and metabolic and sleep disorders.