title: Effects of artificial light at night on human health: A literature review of observational and experimental studies applied to exposure assessment.
abstract: It has frequently been reported that exposure to artificial light at night (ALAN) may cause negative health effects, such as breast cancer, circadian phase disruption and sleep disorders. Here, we reviewed the literature assessing the effects of human exposure to ALAN in order to list the health effects of various aspects of ALAN. Several electronic databases were searched for articles, published through August 2014, related to assessing the effects of exposure to ALAN on human health; these also included the details of experiments on such exposure. A total of 85 articles were included in the review. Several observational studies showed that outdoor ALAN levels are a risk factor for breast cancer and reported that indoor light intensity and individual lighting habits were relevant to this risk. Exposure to artificial bright light during the nighttime suppresses melatonin secretion, increases sleep onset latency (SOL) and increases alertness. Circadian misalignment caused by chronic ALAN exposure may have negative effects on the psychological, cardiovascular and/or metabolic functions. ALAN also causes circadian phase disruption, which increases with longer duration of exposure and with exposure later in the evening. It has also been reported that shorter wavelengths of light preferentially disturb melatonin secretion and cause circadian phase shifts, even if the light is not bright. This literature review may be helpful to understand the health effects of ALAN exposure and suggests that it is necessary to consider various characteristics of artificial light, beyond mere intensity.
authors.affiliation: a Institute for Occupational & Environmental Health, Korea University , Seoul , Republic of Korea and.
authors.forename: YongMin
authors.initials: Y
authors.lastname: Cho
authors.affiliation: a Institute for Occupational & Environmental Health, Korea University , Seoul , Republic of Korea and.
authors.forename: Seung-Hun
authors.initials: SH
authors.lastname: Ryu
authors.affiliation: a Institute for Occupational & Environmental Health, Korea University , Seoul , Republic of Korea and.
authors.forename: Byeo Ri
authors.initials: BR
authors.lastname: Lee
authors.affiliation: a Institute for Occupational & Environmental Health, Korea University , Seoul , Republic of Korea and.
authors.forename: Kyung Hee
authors.initials: KH
authors.lastname: Kim
authors.affiliation: b Department of Preventive Medicine , College of Medicine, Korea University , Seoul , Republic of Korea.
authors.forename: Eunil
authors.initials: E
authors.lastname: Lee
authors.affiliation: a Institute for Occupational & Environmental Health, Korea University , Seoul , Republic of Korea and.|b Department of Preventive Medicine , College of Medicine, Korea University , Seoul , Republic of Korea.
authors.forename: Jaewook
authors.initials: J
authors.lastname: Choi
mesh_terms: D001943:Breast Neoplasms / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D057906:Circadian Clocks / Q000528:radiation effects*; D002940:Circadian Rhythm / Q000528:radiation effects*; D005260:Female; D006801:Humans; D008029:Lighting / Q000009:adverse effects*; D008297:Male; D008550:Melatonin / Q000378:metabolism; D009381:Neoplasms, Radiation-Induced / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D064887:Observational Studies as Topic; D017440:Photoperiod; D018570:Risk Assessment; D012307:Risk Factors; D015398:Signal Transduction; D012890:Sleep / Q000528:radiation effects; D012893:Sleep Wake Disorders / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D013472:Sunlight / Q000009:adverse effects*; D013997:Time Factors; D014851:Wakefulness / Q000528:radiation effects
chemical_list: D008550:Melatonin
keywords: Artificial light at night; breast cancer; circadian rhythm; light exposure; light pollution