Light Pollution Research Articles

Nocturnal Artificial Light Exposure in Expectant Mothers and Risk of Congenital Glaucoma

Abstract Background While the impact of light pollution on human health is gaining recognition, its role in transmitting the effects of maternal exposure to the fetus remains unclear. This study is to investigate the association between exposure to artificial light at night (ALAN) during pregnancy and risk of congenital glaucoma. Methods All birth cohorts spanning from 2008 to 2011 in urban areas of South Korea, comprising over 90% of the total population, were identified in the Korean National Health Insurance database. Average levels of ALAN at the residential addresses of mothers during pregnancy were estimated using time-varying satellite data for a composite view of persistent night-time illumination at ∼1 km2 scale.The odd ratios (ORs) and 95% confidence intervals (CIs) of the association between residential ALAN and risk of congenital glaucoma - was computed using logistic regression. These calculations were adjusted for socio-demographic factors and area-level risk factors (night-time traffic noise and particulate matter with an aerodynamic diameter ≤ 10 μm). Results A total of 745,458 mother-father-child trios (mean [SD] age of the mothers, 32.4 [3.8] years; 387,275 [52.0%] boy) were included in the study. In fully adjusted models, an IQR (21.8 nW/cm2/sr) increase in ALAN level was associated with an OR of 1.12 (95% CI: 1.05, 1.19) for incident congenital glaucoma. The exposure-response curve demonstrated an upward slope with a threshold at approximately 62 nW/cm2/sr. Conclusions In this nationwide population-based case-control study, higher levels of residential ALAN during pregnancy were associated with increased risk of congenital glaucoma. Future studies with more detailed information on exposure, individual adaptive behaviors and potential mediators are warranted. Key messages • This study indicates an association between elevated levels of ALAN exposure in pregnant women and a heightened risk of congenital glaucoma in their offspring. • These results are consistent with a growing body of evidence underscoring the detrimental effects of ALAN on health, reinforcing its potential role as a risk factor for congenital glaucoma.

Urban sensory conditions alter rival interactions and mate choice in urban and forest túngara frogs

Abstract Sexual communication often takes place in networks with multiple competing signalers being simultaneously assessed by mate choosers. Altered sensory conditions, such as noise and light pollution, can affect communication by altering signal production and perception. While evidence of sensory pollution affecting sexual signaling is widespread, few studies assess impacts on sexual signaling during rival interactions as well as mate choice, let alone whether urban and non-urban populations have diverged in their response. Here, we investigate the effects of urban sensory conditions on sexual communication in urban and forest túngara frogs (Engystomops pustulosus). We recorded dyadic vocal rival interactions and assessed mate choice with and without noise and light pollution in the lab. We show that urban sensory conditions can directly impact the intensity of rival interactions, differences between rivals and mate choice, though changes were often in opposite directions for frogs of urban and forest origins. Moreover, we demonstrate that urban-induced changes in rival interactions can also indirectly affect how females choose between potential mates. Our study reveals origin-dependent direct and indirect effects of noise and light pollution, and suggests local adaptation of sexual communication in urban populations.

DARKNESS MATTERS

Darkness Matters displays historic lightscapes, specifically at night, from petroglyphs to James Webb Telescope images. The exposition constructs a sort of cabinet of curiosities and wants to take the visitor on a private journey to a virtual exhibition space to re-embrace the endeavors under and around the nocturnal vault, an underrepresented micro-story of our times. By researching archive material, image recordings and other available data Costanza Julia Bani creates speculative reconstructions of our nights and our relationship to the universe behind the sky we can see with our naked eye. Starting from fireflies in olive groves, alpine forests and the Milky Way, the exposition becomes a visual experience around darknesses and light pollution that has been transforming our nocturnal habitat since the introduction of artificial light.

Nighttime Street View Imagery: A new perspective for sensing urban lighting landscape

Urban lighting reflects nocturnal activities and it is traditionally observed using Nighttime Lights (NTL) satellite imagery. Few studies systematically measure the nightscape from a human perspective. This study brings a new paradigm — urban lighting sensing via Nighttime Street View Imagery (SVI). The paradigm draws on the accomplishments of (daytime) SVI and gives attention to its ignored nighttime counterpart. We put forward this idea by manually collecting 2,831 nighttime SVIs across various urban functional areas in Singapore. We investigated their values by developing a use case for clustering nighttime lighting patterns. To mitigate the scarcity of nighttime SVI, deep learning regression models were trained to predict nighttime brightness based on corresponding daytime SVIs obtained from widely available sources. The results were compared with brightness data derived from satellite imagery, to affirm the novelty and uniqueness of nighttime SVI. As a result, there are 7 lighting patterns within the collected nighttime SVI, distinct in lighted spot features and total brightness. The identified patterns effectively characterize different urban function scenarios. The best trained brightness prediction model performs well in revealing the city-scale lighting landscape. The SVI-predicted brightness shows a distribution similar to the brightness from satellite imagery and complements it in urban areas with complex vertical lighting structures. This study demonstrates the potential of nighttime SVI as a valuable data source for mapping urban lighting and activities, offering advantages over satellite data. The proposed paradigm contributes significantly to cross-modal information mining in urban studies and has potential applications in scenarios such as light pollution mitigation and crime prevention.

Quantifying Night Sky Brightness as a Stressor for Coastal Ecosystems in Moreton Bay, Queensland

Growing light pollution is increasingly studied in terrestrial environments. However, research on night lights in coastal ecosystems is limited. We aimed to complement spaceborne remote sensing with ground-based hemispheric photos to quantify the exposure of coastal habitats to light pollution. We used a calibrated DSLR Canon camera with a fisheye lens to photograph the night sky in 24 sites in the rapidly developing area of Moreton Bay, Queensland, Australia, extracting multiple brightness metrics. We then examined the use of the LANcubeV2 photometer and night-time satellite data from SDGSAT-1 for coastal areas. We found that the skies were darker in less urbanized areas and on islands compared with the mainland. Sky brightness near the zenith was correlated with satellite observations only at a coarse spatial scale. When examining light pollution horizontally above the horizon (60–80° degrees below the zenith), we found that the seaward direction was brighter than the landward direction in most sites due to urban glow on the seaward side. These findings emphasize the importance of ground measurements of light pollution alongside satellite imagery. In order to reduce the exposure of coastal ecosystems to light pollution, actions need to go beyond sites with conservation importance and extend to adjacent urban areas.

Analysis of green productivity in manufacturing based on different air pollution levels

China’s manufacturing industry needs to change from a high-emission model to one that is more environmentally friendly to reduce air pollution and achieve sustainable growth. Therefore, it is important to decrease manufacturing waste gas emissions by improving green productivity. This paper expands on the theories of green economic growth and sustainable development to present a framework for analysis of manufacturing green productivity at various levels of air pollution. It applies the Metafrontier Malmquist Luenberger index and SBM model to data from 30 Chinese manufacturing sectors from 2012 to 2022 to identify the obstacles to developing green productivity in the manufacturing sectors. The results show that: (1) From 2012 to 2022, the overall waste gas emission efficiency and GTFP of China’s manufacturing industry showed an increasing trend. (2) The manufacturing industry with light air pollution had the fastest growth in GTFP, followed by manufacturing with heavy air pollution, and manufacturing with moderate air pollution had the lowest. (3) The primary driver of GTFP growth is technological progress, while technical inefficiency has severely hindered GTFP growth. (4) There is a “Matthew effect” in the green productivity of China’s manufacturing industry. High waste gas emission efficiency often accompanies high levels of GTFP, and vice versa. Finally, this paper proposes policy suggestions to improve the green productivity of the manufacturing industry and reduce air pollution.

Shedding light with harmonic radar: Unveiling the hidden impacts of streetlights on moth flight behavior

One of the most dramatic changes occurring on our planet is the ever-increasing extensive use of artificial light at night, which drastically altered the environment to which nocturnal animals are adapted. Such light pollution has been identified as a driver in the dramatic insect decline of the past years. One nocturnal species group experiencing marked declines are moths, which play a key role in food webs and ecosystem services such as plant pollination. Moths can be easily monitored within the illuminated area of a streetlight, where they typically exhibit disoriented behavior. Yet, little is known about their behavior beyond the illuminated area. Harmonic radar tracking enabled us to close this knowledge gap. We found a significant change in flight behavior beyond the illuminated area of a streetlight. A detailed analysis of the recorded trajectories revealed a barrier effect of streetlights on lappet moths whenever the moon was not available as a natural celestial cue. Furthermore, streetlights increased the tortuosity of flights for both hawk moths and lappet moths. Surprisingly, we had to reject our fundamental hypothesis that most individuals would fly toward a streetlight. Instead, this was true for only 4% of the tested individuals, indicating that the impact of light pollution might be more severe than assumed to date. Our results provide experimental evidence for the fragmentation of landscapes by streetlights and demonstrate that light pollution affects movement patterns of moths beyond what was previously assumed, potentially affecting their reproductive success and hampering a vital ecosystem service.

Setting up light and noise maps to define the contours of a reserve of darkness and silence in Sherbrooke, Québec, Canada

Urban sprawl brings cities closer to natural areas, making them cohabit is a significant environmental challenge. Densification can also increase light and noise pollution, negatively affecting human and biodiversity well-being. Grounded on a collaboration between a college and a university, this work combines brightness and noise maps to establish the contours of a reserve of darkness and silence in Sherbrooke's Mont-Bellevue Park (Québec, Canada). The light and sound environments of the city are mapped by the research team using two devices mounted on vehicles or bicycles: a multispectral and multidirectional brightness sensor and a sound level meter. Long-term and fixed-point light and noise measurements were also conducted to develop the mobile measurement protocol. Wind tunnel measurements in an anechoic chamber were finally used to determine the effect of travel speed on measured noise levels, showing that speeds of less than 15 km/h ensure unbiased acoustic measurements using a windscreen. Perspectives include using the Noise Capture application to provide crowdsourced and additional noise levels at fixed measurement points. The open-source Noise Modelling tool will provide us with calculated environmental noise maps to be compared with measured data.

Light Pollution and Its Effects on Human Health and the Environment: A Review

Light Pollution and Its Effects on Human Health and the Environment: A Review

Do seabirds dream of artificial lights? Understanding light preferences of Procellariiformes.

Seabirds, and particularly fledglings of burrow-nesting species, are greatly impacted by light pollution. During their inaugural flights from colony to sea, fledglings become grounded after encountering artificial light. Such groundings, or fallout events, affect many fledglings each year, causing mass mortality events. To mitigate this light-induced mortality, rescue programmes have been implemented for decades at many locations worldwide. Despite the notoriety of fallouts and their conservation implications, the contributing behavioural and biological factors remain mostly unknown. How the mechanisms of light attraction and light avoidance interact and how they manifest in different groups (e.g. age, personality, populations) or light pollution levels remain open questions. We tested behavioural choices of Cory's shearwater Calonectris borealis fledglings, rescued after being grounded in urban areas, and choices of breeding adults for contrasting light sources. Fledglings and adults were exposed to one of three treatments in an experimental Y-maze set-up: white light versus no light, blue versus red light, and a control with no light on each arm of the Y-maze. Both age groups clearly chose the no-light arms and the red light arm. This choice for longer wavelengths and darker environments, along with slower responses by fledglings, suggests that close range artificial light causes disorientation in seabirds. Our study helps to clarify the behavioural components of fallouts and provides further evidence on the disruptive effects of nocturnal artificial light on sensitive species like Procellariiformes.

Interactive correlations between artificial light at night, health risk behaviors, and cardiovascular health among patients with diabetes: A cross-sectional study.

Artificial light at night (ALAN) is a common phenomenon and contributes to the severe light pollution suffered by more than 80% of the world's population. This study aimed to evaluate the relationship between outdoor ALAN exposure and cardiovascular health (CVH) in patients with diabetes and the influence of various modifiable factors. A survey method based on the China Diabetes and Risk Factor Monitoring System was adopted. Study data were extracted for 1765 individuals with diabetes in Anhui Province. Outdoor ALAN exposure (nW/cm2/sr) within 1000 m of each participant's residential address was obtained from satellite imagery data, with a resolution of ~1000 m. Health risk behaviors (HRBs) were measured via a standardized questionnaire. A linear regression model was employed to estimate the relationship between outdoor ALAN, HRBs, and CVH. Participants' mean age was 59.10 ± 10.0 years. An association was observed between ALAN and CVH in patients with diabetes (β = 0.205) and exercise (β = -1.557), moderated by HRBs, or metabolic metrics. There was an association between ALAN, ALAN, vegetable intake, and CVH. Exploring the relationship between ALAN exposure and cardiovascular and metabolic health provides policy data for improving light pollution strategies and reducing the risk of cardiovascular and metabolic disease in patients with diabetes.

Elevated vitamin D levels in diurnally-active female fruit bats

Animal species have evolved to enhance their survival by focusing their temporal activity on specific parts of the diurnal-nocturnal cycle. Various factors, including inter-specific competition and anti-predator behavior, as well as anthropogenic effects like light pollution, have prompted some species to expand or shift their temporal niches. Our study focuses on the temporal niche shift of the Egyptian fruit bat (Rousettus aegyptiacus) to diurnal activity in Israel.Through an extensive citizen-science study, we assessed the distribution of these bats’ diurnal activity across Israel. We also documented the sex and age of bats from a colony known for its diurnal activity and collected blood samples from them for metabolic analysis.Our findings indicate that the shift toward daytime activity predominantly takes place in urban settings and is mostly exhibited by females. We found a significant physiological effect of this temporal shift, namely: diurnal bats’ vitamin D levels were significantly higher, and their parathyroid hormone (PTH) levels were significantly lower than those of nocturnal bats.We suggest that the reproductive metabolic demands of female bats might be a key factor driving this shift to diurnal activity. We hypothesize that the increase in vitamin D, derived from sunlight hours, might play a crucial role in regulating calcium homeostasis, thus contributing to the bats’ physiological needs during the reproduction season.

Blue and white light pollution is disastrous for Cory's shearwater fledglings

Blue and white light pollution is disastrous for Cory's shearwater fledglings

Antagonistic Effects of Light Pollution and Warming on Habitat-Forming Seaweeds.

Artificial Light at Night (ALAN) is an emerging global stressor that is likely to interact with other stressors such as warming, affecting habitat-forming species and ecological functions. Seaweeds are dominant habitat-forming species in temperate marine ecosystems, where they support primary productivity and diverse ecological communities. Warming is a major stressor affecting seaweed forests, but effects of ALAN on seaweeds are largely unknown. We manipulated ALAN (0 lx vs. 25 lx at night) and temperature (ambient vs. +1.54°C warming) to test their independent and interactive effects on the survival, growth (biomass, total-, blade- and stipe-length) and function (photosynthesis, primary productivity and respiration) on the juveniles of two habitat-forming seaweeds, the kelp Ecklonia radiata and the fucoid Sargassum sp. Warming significantly increased Ecklonia mortality; however, ALAN did not affect mortality. ALAN had positive effects on Ecklonia biomass, total and blade growth rates and gross primary productivity; however, warming largely counterbalanced these effects. We found no significant effects of warming or ALAN on Ecklonia photosynthetic yield, stipe length, net primary productivity or respiration rates. We found no effects of ALAN or warming on Sargassum for any of the measured variables. Synthesis. Our findings indicate that ALAN can have positive effects on seaweed growth and functioning, but such effects are likely species-specific and can be counterbalanced by warming, suggesting an antagonistic interaction between these global stressors. These findings can help us to predict and manage the effects of these stressors on seaweeds, which underpin coastal biodiversity.

Anthropogenic noise and light pollution decrease the repeatability of activity patterns and dampen expression of chronotypes in a free-living songbird

Anthropogenic environmental change is introducing a suite of novel disturbance factors, which can have wide-ranging effects on mean behavior and behavioral repeatability. For example, exposure to sensory pollutants, such as anthropogenic noise and artificial light at night (ALAN), may affect consistent and repeatable individual-level timing of daily activity, which is referred to as chronotypes. Although chronotypes have been increasingly documented in wild animal populations and may affect fitness, evidence for long-term stability across life-history stages and seasons is notably lacking. Furthermore, how multiple anthropogenic stressors may interact to erode or magnify the expression of chronotypes remains unclear. We tested for existence of chronotypes across life-history stages and seasons in suburban female great tits (Parus major), using emergence time from nest boxes in the morning as a proxy for activity onset. We then examined joint effects of noise pollution and ALAN on expression of chronotypes, and tested for effects of noise, ALAN, and weather conditions on mean emergence time. We found repeatability of daily activity patterns (emergence times) across life-history stages and seasons, providing evidence of chronotypes, as well as interactive effects of anthropogenic disturbance factors and weather conditions on population mean behavior. Furthermore, across-season repeatability of emergence times was approximately double in magnitude in low light and low noise conditions, relative to in conditions with higher light and/or noise pollution. Thus, joint exposure to these sensory pollutants tends to erode expression of chronotypes. This effect was driven by higher among-individual variance in the relatively undisturbed environment and collapse of this variance in the more disturbed environments. Decreased repeatability in environments with high disturbance levels may reduce potential for behavioral traits, such as chronotype, to be the target of selection and limit adaptability.

Quantifying the visual impact of wind farm lights on the nocturnal landscape

Wind farm lights are a conspicuous feature in the nocturnal landscape. Their presence is a source of light pollution for residents and the environment, severely disrupting in some places the aesthetic, cultural, and scientific values of the pristine starry skies. In this work we present a simple model for quantifying the visual impact of individual wind turbine lights, based on the comparison of their brightness with the brightness of well-known night sky objects. The model includes atmospheric and visual variables, and for typical parameters it shows that medium-intensity turbine lights can be brighter than Venus up to ∼4 km from the turbine, brighter than α CMa (the brightest star on the nighttime sky) until about ∼10 km, and reach the standard stellar visibility limit for the unaided eye (mv = +6.00) at ∼38 km. These results suggest that the visual range of wind farms at nighttime may be significantly larger than at daytime, a factor that should be taken into account in environmental impact assessments.

Light Pollution: To What Extent We are Concerned About

Light pollution is now a global problem with a catastrophic impact on human health, environment, ecology, plant life cycle, and animals. Some nations have enacted laws aimed at limiting light pollution. Unfortunately, there is no such regulation in Bangladesh, and if there is, it is not being enforced. In this study, an attempt has been made to investigate people's perceptions of light pollution in Bangladesh. This study collected three hundred forty samples using a convenient sampling technique. Descriptive statistics were employed to analyze the data. Among the sources, the respondents identified commercial light, fireworks, light from the market, and light from billboards as the major sources of light pollution. Besides light from the neighbor's house, own domestic light, events light, and light from home were assumed to be the significant disturbing light sources. Findings showed that most respondents agreed with the hazardous impact of light pollution on human health, animals, the environment, and the ecosystem. Among the possible solutions, respondents recommended developing awareness, limiting light at night-time, cutting off unnecessary lights, and reducing the frequent use of decorative lights. Results conclude that people have a sound understanding and good perception of light pollution. So the associate agents can take appropriate steps toward light pollution control.

Geochemical baseline establishment and accumulation characteristics of soil heavy metals in Sabaochaqu watershed at the source of Yangtze River, Qinghai-Tibet Plateau

The establishment of soil geochemical baseline and heavy metal pollution assessment in the Qinghai-Tibet Plateau is of great significance for guiding environmental management in the high-cold and high-altitude regions. A total of 126 topsoil samples (0–20 cm) were collected and the contents of Cu, Pb, Zn, Ni, Cr, Cd, As and Hg were determined in the Sabaochaqu basin of the Tuotuo River, the source of the Yangtze River, in the Tibetan Plateau. The baseline values of 8 heavy metals were determined by mathematical statistics, iterative 2times standard deviation method, cumulative frequency and reference element standardization, and the soil heavy metal pollution in the study area was assessed by enrichment factor method and pollution index method. The results showed that the average contents of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were 31.84, 0.29, 66.07, 17.35, 0.021, 27.86, 49.35 and 88.56 mg/kg, respectively. Baseline values were 22.24, 0.217, 64.16, 15.69, 0.0191, 26.46, 34.91, and 68.62 mg/kg, respectively. There is a great difference between the baseline value of soil heavy metals in study area and the Xizang soil background value, especially the baseline value of Cd was 2.68 times of its background value. The results of the pollution evaluation based on the baseline values showed that the 8 heavy metals were slightly enriched, and the overall pollution status was light pollution, and measures should be taken to control and manage them. The research results can provide a reference value for the evaluation of soil heavy metal pollution in the source region of the Yangtze River, and also provide a theoretical basis for the construction of soil heavy metal baseline values in similar high-cold and high-altitude regions.

An Innovative New Approach to Light Pollution Measurement by Drone

The study of light pollution is a relatively new and specific field of measurement. The current literature is dominated by articles that describe the use of ground and satellite data as a source of information on light pollution. However, there is a need to study the phenomenon on a microscale, i.e., locally within small locations such as housing estates, parks, buildings, or even inside buildings. Therefore, there is an important need to measure light pollution at a lower level, at the low level of the skyline. In this paper, the authors present a new drone design for light pollution measurement. A completely new original design for an unmanned platform for light pollution measurement is presented, which is adapted to mount custom sensors (not originally designed to be mounted on a unmanned aerial vehicles) allowing registration in the nadir and zenith directions. The application and use of traditional photometric sensors in the new configuration, such as the spectrometer and the sky quality meter (SQM), is presented. A multispectral camera for nighttime measurements, a calibrated visible-light camera, is used. The results of the unmanned aerial vehicle (UAV) are generated products that allow the visualisation of multimodal photometric data together with the presence of a geographic coordinate system. This paper also presents the results from field experiments during which the light spectrum is measured with the installed sensors. As the results show, measurements at night, especially with multispectral cameras, allow the assessment of the spectrum emitted by street lamps, while the measurement of the sky quality depends on the flight height only up to a 10 m above ground level.

Light pollution: time to consider testicular effects.

Technological advances have led to a modern-day lighting and smartphone revolution, with artificial light exposure at night increasing to levels never before seen in the evolutionary history of living systems on Earth. Light as a pollutant, however, remains largely unrecognized, and the reproductive effects of light pollution are mostly if not entirely unconsidered. This is despite the reproductive system being intricately linked to metabolism and the circadian system, both of which can be disturbed even by low levels of light. Here, we aim to change this perspective by reviewing the physiological and pathophysiological mechanisms by which light exposure alters the intricate hormonal, metabolic and reproductive networks that are relevant to reproductive toxicology. Nascent human studies have recently identified the photoreceptors responsible for the light dose relationship with melatonin suppression and circadian re-entrainment, directly shown the association between the alignment of light-dark cycles with activity-rest cycles on metabolic health and provided proof-of-principle that properly timed blue light-enriched and blue light-depleted delivery can accelerate circadian re-entrainment. With these advances, there is now a need to consider testicular effects of light pollution.