Preface -- Introduction -- PART 1: ARTIFICIAL LIGHT AND HUMAN TEMPORAL ORGANIZATION -- Artificial light and its physicochemical properties (by Fabio Falchi) -- Light and dark cycles as a basis of temporal organization -- The biological clock and its entrainment by photoperiod -- LAN exposure and its potential effects on daily rhythms and seasonal disruptions -- Melatonin (MLT) -"hormone of darkness" and a "jack of all traits" -- PART II: LIGHT POLLUTION, ITS KNOWN HEALTH EFFECTS AND IMPACT ON ENERGY CONSERVATION -- Introduction and spread of artificial illumination - a human history retrospective -- Biological definition of light pollution -- Light pollution as a general stressor -- The effects of light pollution on animal rhythms and ecology -- Light pollution and hormone-dependent cancers: summary of accumulated empirical evidence -- PART III: LIGHT POLLUTION AND ITS POTENTIAL LINKS TO BREAST AND PROSTATE CANCERS -- Geographic patterns of breast and prostate cancers (BC&PC) worldwide -- Light pollution and its association with breast and prostate cancers (BC&PC) in population-level studies -- Selected methodological issues of Light-at-Night (LAN) - Breast and Prostate Cancers (BC&PC) research -- Dark-less world - what is next? (Conclusions and prospects for future research) -- BIBLIOGRAPHY -- ADDITIONAL READING.