Light pollution, circadian photoreception, and melatonin in vertebrates

Grubisic, M. et al. (2019) Light pollution, circadian photoreception, and melatonin in vertebrates. Sustainability, 11(22), e6400. (doi: 10.3390/su11226400)

Abstract

Artificial light at night (ALAN) is increasing exponentially worldwide, accelerated by the transition to new efficient lighting technologies. However, ALAN and resulting light pollution can cause unintended physiological consequences. In vertebrates, production of melatonin—the “hormone of darkness” and a key player in circadian regulation—can be suppressed by ALAN. In this paper, we provide an overview of research on melatonin and ALAN in vertebrates. We discuss how ALAN disrupts natural photic environments, its effect on melatonin and circadian rhythms, and different photoreceptor systems across vertebrate taxa. We then present the results of a systematic review in which we identified studies on melatonin under typical light-polluted conditions in fishes, amphibians, reptiles, birds, and mammals, including humans. Melatonin is suppressed by extremely low light intensities in many vertebrates, ranging from 0.01−0.03 lx for fishes and rodents to 6 lx for sensitive humans. Even lower, wavelength-dependent intensities are implied by some studies and require rigorous testing in ecological contexts. In many studies, melatonin suppression occurs at the minimum light levels tested, and, in better-studied groups, melatonin suppression is reported to occur at lower light levels. We identify major research gaps and conclude that, for most groups, crucial information is lacking. No studies were identified for amphibians and reptiles and long-term impacts of low-level ALAN exposure are unknown. Given the high sensitivity of vertebrate melatonin production to ALAN and the paucity of available information, it is crucial to research impacts of ALAN further in order to inform effective mitigation strategies for human health and the wellbeing and fitness of vertebrates in natural ecosystems.

• Item Type: Articles
• Additional Information: This article is based upon work from COST Action ES1204 LoNNe (Loss of the Night Network), supported by COST (European Cooperation in Science and Technology). M.G. was supported by a DRH HONORS fellowship by the Freie Universität Berlin. A.J. was supported by the Leibniz Association, Germany within the ILES (SAW-2015-IGB-1 415) and CONNECT (SAW-K45/2017) projects, and by the IGB Leibniz Institute through the Frontiers in Freshwater Science project (IGB Frontiers 2017). F.K. was supported by the Leibniz Association, Germany within the ILES (SAW-2015-IGB-1 415). W.R. was partially supported by the Center for Environment, Fisheries, and Aquaculture Science (Cefas), and the UK Government’s Department for Environment, Food, and Rural Affairs (Defra) under contracts SF0258 and SA001. M.Z. and K.S. were partially supported by the Slovak Research and Development Agency APVV-17-0178. The publication of this article was funded by the Open Access Fund of the Leibniz Association.
• Keywords: ALAN, artificial light at night, biological rhythm, circadian rhythm, melatonin.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Dominoni, Dr Davide

Creator Roles

Dominoni, D. M.: Investigation, Writing – original draft, Writing – review and editing

• Authors: Grubisic, M., Haim, A., Bhusal, P., Dominoni, D. M., Gabriel, K. M.A., Jechow, A., Kupprat, F., Lerner, A., Marchant, P., Riley, W., Stebelova, K., van Grunsven, R. H.A., Zeman, M., Zubidat, A. E., and Hölker, F.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Sustainability
• Publisher: MDPI
• ISSN: 2071-1050
• ISSN (Online): 2071-1050
• Copyright Holders: Copyright © 2019 The Authors
• First Published: First published in Sustainability 11(22):e6400
• Publisher Policy: Reproduced under a Creative Commons License