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Written Communications
From:Mark Baker To:City of Cupertino Planning Dept. Cc:Puragra Guhathakurta; Shani Kleinhaus Subject:Outdoor Lighting Date:Friday, August 7, 2020 1:53:28 PM Attachments:ALAN Research Studies.pdf LED Light Cancer Risk.pdf Letter to City Council.pdf Light And Safety.pdf AP2014SA0253EN.pdf AMA_Report_2016_60.pdf IDA-State-Of-The-Science-2020.pdf SoftLightsOutdoorLightingDesignGuide.pdf CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe. Dear City of Cupertino, This is a public comment regarding the proposed standards for Outdoor Lighting. Soft Lights ( www.softlights.org )is an advocacy group dedicated to educating decision makers about the dangers of light pollution and LED lights. We are excited to see Cupertino's efforts to protect darkness and limit light pollution. Darkness is a fundamental necessity for biological systems, including humans, birds, insects and plants. Light pollution has been increasing rapidly and now rivals air and water pollution in terms of serious threats to our health. To protect human health, the health of other living creatures and the entire ecosystem, we wish to make the following recommendations. 1) The American Medical Association set the 3000 Kelvin color temperature maximum in 2016 when there wasn't as much research about blue wavelength light. Now that we know more details, 3000K is too high. For the approximately 20% of the population that has Sensory Processing Sensitivity (SPS) such as those who are highly sensitive persons, those with autism, photophobia and migraine sufferers, the difference between 2700K and 3000K is noticeable and can be the difference between comfortable and a migraine headache. Therefore, we urge the council to change the wording for color temperature to something like: "The maximum color temperature for areas with bats shall be 1000K, 1600K for rural areas, 2200K for residential areas, and 2700K for business areas. In no case shall any outdoor light exceed 2700K." 2) I didn't see anything about sensitive receptors. Please add a section about the Americans with Disabilities Act and that the ADA prohibits discrimination against those with light sensitivies. Require that all outdoor lighting be compatible with those with light sensitivity disabilities. Generally, this means 2700K color temperature or less, shielded to avoid light trespass, diffused to prevent eye damage from bare-diode lights and using electronics that prevent sub-sensory flicker. 3) I noticed in the comments that some were concerned about safety. Please assure your constituents that bright lights do nothing to make use safer. In fact, high glare lights make us less safe. We realize that some people fear the dark, but lighting up the night with bright lights is not a solution due to the numerous health risks involved. Humans have incredibly sensitive eyes. Using a tiny amount of light to allow us to navigate at night is useful, but at no time should we try to add light in the name of "safety". 4) We are thrilled to see the limit on strobing and blinking lights. The new generation of LED strobe lights that have suddenly appeared on utility trucks, police cars, tow trucks, stop signs, speed limit signs, radio towers and bridges is making our lives miserable. Supposedly these strobe lights were installed in the name of safety, but the idea of shining high energy lights directly into people's eyes is ludicrous. Humans are not robots. We cannot have strobing photons being shot into our eyes everywhere we go. If this current proposal does not cover mobile LED strobe lights such as on utility trucks, then we urge the council to prohibit these strobe lights in a different proposal. I am attaching a number of documents to help the city with its decision making. Sincerely, Mark Baker, B.S.E.E. Soft Lights www.softlights.org June 19, 2020 by Soft Lights ALAN Research Studies By Soft Lights This document lists research studies on the impacts of Artificial Light at Night. Humans Eyes 1. “light has a cumulative effect” – National Institutes of Health (2016) - Effects of Blue Light on the Circadian System and Eye Physiology 2. ”At the molecular level, analyses revealed an increase of oxidative stress followed by cell death” – National Institutes of Health (2016) - Effects of white light‐emitting diode (LED) exposure on retinal pigment epithelium in vivo 3. ”Exposure to blue LED light for 3 days induced retinal damage” – National Institutes of Health (2018) - Exposure to Excessive Blue LED Light Damages Retinal Pigment Epithelium and Photoreceptors of Pigmented Mice 4. ”LED blue-light exposure poses a great risk of retinal injury in awake, task-oriented rod-dominant animals.” – National Institutes of Health (2018) - Light-emitting-diode induced retinal damage and its wavelength dependency in vivo 5. ”LED light caused a state of suffering of the retina with oxidative damage and retinal injury.” – National Institutes of Health (2015) - Retinal Damage Induced by Commercial Light Emitting Diodes (LEDs) 6. ”blue-light induced photochemical injury of the retina.” – National Institutes of Health (2014) - White Light-Emitting Diodes (LEDs) at Domestic Lighting Levels and Retinal Injury in a Rat Model 7. ” retinal damage by intermittent light exposure promotes an irreversible damage” – Nature (2015) - Light pollution: the possible consequences of excessive illumination on retina Health 1. “light at night negatively affects mood” – National Institutes of Health (2017) – Timing of light exposure affects mood and brain circuits 2. ”LAN levels were associated with higher incidence of breast cancer” – National Institutes of Health (2010) – LIGHT POLLUTION: Light at Night and Breast Cancer Risk Worldwide 3. ”Just like sunset, the light source (1900 K) is an “artificial light of harmony” which promote the secretion of melatonin, resulting in an improved sleeping quality” – Nature (2019) – Several biological benefits of the low color temperature light-emitting diodes based normal indoor lighting source 4. “The human circadian system is exquisitely sensitive to the spectrum of light visible to the eye, especially blue wavelengths” - German-Spanish Astronomical Centre (2018) - Including an index measuring the weighted content of blue light in lamp June 19, 2020 by Soft Lights 5. “LAN acts through estrogen receptor signaling–mediated pathways to increase breast cancer risk” – Environmental Health Perspectives (2017) - Outdoor Light at Night and Breast Cancer Incidence in the Nurses’ Health Study II 6. “Melatonin Inhibits Angiogenesis in Breast, Prostate, and Ovarian Cancers” – International Journal of Endocrinology (2018) - Melatonin: An Anti-Tumor Agent in Hormone-Dependent Cancers 7. “exposure to blue light from white LEDs under an LDPP suppresses melatonin secretion” – Animal Science Journal (2020) - Exposure to blue LED light before the onset of darkness under a long‐day photoperiod alters melatonin secretion, feeding behaviour and growth in female dairy calve 8. “Adolescents in areas with greater levels of nighttime light also had higher prevalence of past-year mood and anxiety disorders.” – Jama Psychiatry (2020) - https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2767698 9. Risk of Colon Cancer increase 60% - https://www.usnews.com/news/health- news/articles/2020-07-31/how-streetlights-might-affect-your-colon-cancer-risk 10. Damien McNamara’s Autistic Son - https://www.stuff.co.nz/national/116865102/effects-of-led-streetlights-on-autistic-son- led-damien-mcnamara-on-dark-sky-campaign Safety 1. “We found no convincing evidence for associations between street lighting reductions and road traffic injuries.” – National Institute for Health Research (2015) - The effect of reduced street lighting on crime and road traffic injuries at night in England and Wales: a controlled interrupted time series analysis 2. (Same study as above) “an association between dimming and reductions in crime, particularly for violent crime.” – Journal of Epidemiology and Community Health (2015) - The effect of reduced street lighting on crime and road traffic injuries at night in England and Wales: a controlled interrupted time series analysis 3. (Article) ”evidence is mounting that nighttime brightness may do little to stop crime, and in some cases may make it worse.” – Washington Post (2017) - What actually happens to crime ‘when the lights are on,’ as Rick Perry suggests 4. (Article) ”It may make us feel safer, but has not been shown to make us safer” – International Dark Sky Association (2020) - Lighting, Crime and Safety 5. (Article) ”Spaces with warmer colour temperatures are perceived as safer places.” – The Conversation (2019) - More lighting alone does not create safer cities. Wildlife 1. “we advocate warm color temperature white light as nighttime illumination” - Health and Human Services USA (2018) – Light at night disrupts nocturnal rest and elevates glucocorticoids at cool color temperatures 2. “Alters detection of day and night” - Exeter University (2013) – Measuring biological light pollution and uncovering its ecological effects June 19, 2020 by Soft Lights 3. “the significant impact that even low levels of nighttime light pollution can have” - Cambridge University (2013) - The ecological impacts of nighttime light pollution: a mechanistic appraisal 4. "managers should avoid lights that have ultraviolet or blue light (shorter wavelengths)” - National Park Service (2017) - Artificial Night Lighting and Protected Lands 5. "if the tendency to light more when light is cheaper can be overcome" - Luger Research (2018) - Hazard or Hope? LEDs and Wildlife 6. “use lamps with the lowest CCT, melanopic response, or M/P value possible to achieve the goals of the lighting project.” - Illuminating Engineering Society (2020) - On the Use of Summary Metrics of Light Spectral Characteristics to Assess Effects of Artificial Light at Night on Wildlife 7. “exacerbate existing domestic, e.g., midge swarms and industrial infestations of sanitary and phytosanitary pests” - Ecological Society of America (2014) - LED lighting increases the ecological impact of light pollution irrespective of color temperature 8. “Anthropogenic lighting drastically alters nocturnal environments, threatening a wide range of species” - Colorado State University (2018) - Anthropogenic light disrupts natural light cycles in critical conservation areas 9. “bombarded with numerous novel stimuli in their environment that could lead to grave consequences.” - Journal of Ecology (2018) - Connecting spectral radiometry of anthropogenic light sources to the visual ecology of organisms 10. "ALAN reduces habitat suitability" - El Sevier (2020) - Effects of artificial light at night on the foraging behavior of an endangered nocturnal mammal 11. “Light pollution can have significant conservation consequences for a threatened bat species” - Current Biology (2009) - Street Lighting Disturbs Commuting Bats 12. “Technological innovations and changes in lighting strategies should consider benefits for reductions in greenhouse gases and energy consumption in parallel with their potential ecological impacts” - Global Change Biology (2012) - Conserving energy at a cost to biodiversity? Impacts of LED lighting on bats 13. “The most immediate threat from anthropogenic noise and light is the loss of species” - Trends in Ecology & Evolution (2015) - A framework to assess evolutionary responses to anthropogenic light and sound 14. “When the installation was illuminated, birds aggregated in high densities, decreased flight speeds, followed circular flight paths, and vocalized frequently” - Proceedings of the National Academy of Sciences (2017) - High-intensity urban light installation dramatically alters nocturnal bird migration Public Policy 1. “Glare from nighttime lighting can create hazards ranging from discomfort to frank visual disability” - American Medical Association (2012) – Light Pollution: Adverse Health Effects of Nighttime Lighting June 19, 2020 by Soft Lights 2. "3000K or lower lighting for outdoor installations such as roadways" - American Medical Association (2016) - Human and Environmental Effects of Light Emitting Diode (LED) Community Lighting 3. “limit their exposure to blue-rich lighting” - French Agency for Food, Environmental and Occupational Health & Safety (2019) – Effects on human health and the environment (fauna and flora) of systems using light-emitting diodes (LEDs) 4. “Start with natural darkness and only add light for specific purposes” - Australia Department of Agriculture, Water and the Environment (2020) – National Light Pollution Guidelines for Wildlife Including Marine Turtles, Seabirds and Migratory Shorebirds 5. “CCT threshold at 2700K for the “built environment” of towns and villages, and 2400K otherwise” – French Government (2019) - French Light Pollution Law 6. BirdLife Malta https://timesofmalta.com/articles/view/birdlife-issues-guidelines-for- ecologically-responsible-lighting.808578 Examples Unacceptable June 19, 2020 by Soft Lights Acceptable © 2016 American Medical Association. All rights reserved. REPORT OF THE COUNCIL ON SCIENCE AND PUBLIC HEALTH CSAPH Report 2-A-16 Subject: Human and Environmental Effects of Light Emitting Diode (LED) Community Lighting Presented by: Louis J. Kraus, MD, Chair Referred to: Reference Committee E (Theodore Zanker, MD, Chair) INTRODUCTION 1 2 With the advent of highly efficient and bright light emitting diode (LED) lighting, strong economic 3 arguments exist to overhaul the street lighting of U.S. roadways.1-3 Valid and compelling reasons 4 driving the conversion from conventional lighting include the inherent energy efficiency and longer 5 lamp life of LED lighting, leading to savings in energy use and reduced operating costs, including 6 taxes and maintenance, as well as lower air pollution burden from reduced reliance on fossil-based 7 carbon fuels. 8 9 Not all LED light is optimal, however, when used as street lighting. Improper design of the lighting 10 fixture can result in glare, creating a road hazard condition.4,5 LED lighting also is available in 11 various color correlated temperatures. Many early designs of white LED lighting generated a color 12 spectrum with excessive blue wavelength. This feature further contributes to disability glare, i.e., 13 visual impairment due to stray light, as blue wavelengths are associated with more scattering in the 14 human eye, and sufficiently intense blue spectrum damages retinas.6,7 The excessive blue spectrum 15 also is environmentally disruptive for many nocturnal species. Accordingly, significant human and 16 environmental concerns are associated with short wavelength (blue) LED emission. Currently, 17 approximately 10% of existing U.S. street lighting has been converted to solid state LED 18 technology, with efforts underway to accelerate this conversion. The Council is undertaking this 19 report to assist in advising communities on selecting among LED lighting options in order to 20 minimize potentially harmful human health and environmental effects. 21 22 METHODS 23 24 English language reports published between 2005 and 2016 were selected from a search of the 25 PubMed and Google Scholar databases using the MeSH terms “light,” “lighting methods,” 26 “color,” “photic stimulation,” and “adverse effects,” in combination with “circadian 27 rhythm/physiology/radiation effects,” “radiation dosage/effects,” “sleep/physiology,” “ecosystem,” 28 “environment,” and “environmental monitoring.” Additional searches using the text terms “LED” 29 and “community,” “street,” and “roadway lighting” were conducted. Additional information and 30 perspective were supplied by recognized experts in the field. 31 32 ADVANTAGES AND DISADVANTAGES OF LED STREET LIGHTS 33 34 The main reason for converting to LED street lighting is energy efficiency; LED lighting can 35 reduce energy consumption by up to 50% compared with conventional high pressure sodium (HPS) 36 CSAPH Rep. 2-A-16 -- page 2 of 8 lighting. LED lighting has no warm up requirement with a rapid “turn on and off” at full intensity. 1 In the event of a power outage, LED lights can turn on instantly when power is restored, as 2 opposed to sodium-based lighting requiring prolonged warm up periods. LED lighting also has the 3 inherent capability to be dimmed or tuned, so that during off peak usage times (e.g., 1 to 5 AM), 4 further energy savings can be achieved by reducing illumination levels. LED lighting also has a 5 much longer lifetime (15 to 20 years, or 50,000 hours), reducing maintenance costs by decreasing 6 the frequency of fixture or bulb replacement. That lifespan exceeds that of conventional HPS 7 lighting by 2-4 times. Also, LED lighting has no mercury or lead, and does not release any toxic 8 substances if damaged, unlike mercury or HPS lighting. The light output is very consistent across 9 cold or warm temperature gradients. LED lights also do not require any internal reflectors or glass 10 covers, allowing higher efficiency as well, if designed properly.8,9 11 12 Despite the benefits of LED lighting, some potential disadvantages are apparent. The initial cost is 13 higher than conventional lighting; several years of energy savings may be required to recoup that 14 initial expense.10 The spectral characteristics of LED lighting also can be problematic. LED 15 lighting is inherently narrow bandwidth, with "white" being obtained by adding phosphor coating 16 layers to a high energy (such as blue) LED. These phosphor layers can wear with time leading to a 17 higher spectral response than was designed or intended. Manufacturers address this problem with 18 more resistant coatings, blocking filters, or use of lower color temperature LEDs. With proper 19 design, higher spectral responses can be minimized. LED lighting does not tend to abruptly “burn 20 out,” rather it dims slowly over many years. An LED fixture generally needs to be replaced after it 21 has dimmed by 30% from initial specifications, usually after about 15 to 20 years.1,11 22 23 Depending on the design, a large amount blue light is emitted from some LEDs that appear white 24 to the naked eye. The excess blue and green emissions from some LEDs lead to increased light 25 pollution, as these wavelengths scatter more within the eye and have detrimental environmental 26 and glare effects. LED’s light emissions are characterized by their correlated color temperature 27 (CCT) index.12,13 The first generation of LED outdoor lighting and units that are still widely being 28 installed are “4000K” LED units. This nomenclature (Kelvin scale) reflects the equivalent color of 29 a heated metal object to that temperature. The LEDs are cool to the touch and the nomenclature has 30 nothing to do with the operating temperature of the LED itself. By comparison, the CCT associated 31 with daylight light levels is equivalent to 6500K, and high pressure sodium lighting (the current 32 standard) has a CCT of 2100K. Twenty-nine percent of the spectrum of 4000K LED lighting is 33 emitted as blue light, which the human eye perceives as a harsh white color. Due to the point-34 source nature of LED lighting, studies have shown that this intense blue point source leads to 35 discomfort and disability glare.14 36 37 More recently engineered LED lighting is now available at 3000K or lower. At 3000K, the human 38 eye still perceives the light as “white,” but it is slightly warmer in tone, and has about 21% of its 39 emission in the blue-appearing part of the spectrum. This emission is still very blue for the 40 nighttime environment, but is a significant improvement over the 4000K lighting because it 41 reduces discomfort and disability glare. Because of different coatings, the energy efficiency of 42 3000K lighting is only 3% less than 4000K, but the light is more pleasing to humans and has less 43 of an impact on wildlife. 44 45 Glare 46 47 Disability glare is defined by the Department of Transportation (DOT) as the following: 48 49 “Disability glare occurs when the introduction of stray light into the eye reduces the ability to 50 resolve spatial detail. It is an objective impairment in visual performance.” 51 CSAPH Rep. 2-A-16 -- page 3 of 8 Classic models of this type of glare attribute the deleterious effects to intraocular light scatter in the 1 eye. Scattering produces a veiling luminance over the retina, which effectively reduces the contrast 2 of stimulus images formed on the retina. The disabling effect of the veiling luminance has serious 3 implications for nighttime driving visibility.15 4 5 Although LED lighting is cost efficient and inherently directional, it paradoxically can lead to 6 worse glare than conventional lighting. This glare can be greatly minimized by proper lighting 7 design and engineering. Glare can be magnified by improper color temperature of the LED, such as 8 blue-rich LED lighting. LEDs are very intense point sources that cause vision discomfort when 9 viewed by the human eye, especially by older drivers. This effect is magnified by higher color 10 temperature LEDs, because blue light scatters more within the human eye, leading to increased 11 disability glare.16 12 13 In addition to disability glare and its impact on drivers, many residents are unhappy with bright 14 LED lights. In many localities where 4000K and higher lighting has been installed, community 15 complaints of glare and a “prison atmosphere” by the high intensity blue-rich lighting are common. 16 Residents in Seattle, WA have demanded shielding, complaining they need heavy drapes to be 17 comfortable in their own homes at night.17 Residents in Davis, CA demanded and succeeded in 18 getting a complete replacement of the originally installed 4000K LED lights with the 3000K 19 version throughout the town at great expense.18 In Cambridge, MA, 4000K lighting with dimming 20 controls was installed to mitigate the harsh blue-rich lighting late at night. Even in places with a 21 high level of ambient nighttime lighting, such as Queens in New York City, many complaints were 22 made about the harshness and glare from 4000K lighting.19 In contrast, 3000K lighting has been 23 much better received by citizens in general. 24 25 Unshielded LED Lighting 26 27 Unshielded LED lighting causes significant discomfort from glare. A French government report 28 published in 2013 stated that due to the point source nature of LED lighting, the luminance level of 29 unshielded LED lighting is sufficiently high to cause visual discomfort regardless of the position, 30 as long as it is in the field of vision. As the emission surfaces of LEDs are highly concentrated 31 point sources, the luminance of each individual source easily exceeds the level of visual 32 discomfort, in some cases by a factor of 1000.17 33 34 Discomfort and disability glare can decrease visual acuity, decreasing safety and creating a road 35 hazard. Various testing measures have been devised to determine and quantify the level of glare 36 and vision impairment by poorly designed LED lighting.20 Lighting installations are typically 37 tested by measuring foot-candles per square meter on the ground. This is useful for determining the 38 efficiency and evenness of lighting installations. This method, however, does not take into account 39 the human biological response to the point source. It is well known that unshielded light sources 40 cause pupillary constriction, leading to worse nighttime vision between lighting fixtures and 41 causing a “veil of illuminance” beyond the lighting fixture. This leads to worse vision than if the 42 light never existed at all, defeating the purpose of the lighting fixture. Ideally LED lighting 43 installations should be tested in real life scenarios with effects on visual acuity evaluated in order to 44 ascertain the best designs for public safety. 45 46 Proper Shielding 47 48 With any LED lighting, proper attention should be paid to the design and engineering features. 49 LED lighting is inherently a bright point source and can cause eye fatigue and disability glare if it 50 is allowed to directly shine into human eyes from roadway lighting. This is mitigated by proper 51 CSAPH Rep. 2-A-16 -- page 4 of 8 design, shielding and installation ensuring that no light shines above 80 degrees from the 1 horizontal. Proper shielding also should be used to prevent light trespass into homes alongside the 2 road, a common cause of citizen complaints. Unlike current HPS street lighting, LEDs have the 3 ability to be controlled electronically and dimmed from a central location. Providing this additional 4 control increases the installation cost, but may be worthwhile because it increases long term energy 5 savings and minimizes detrimental human and environmental lighting effects. In environmentally 6 sensitive or rural areas where wildlife can be especially affected (e.g., near national parks or bio-7 rich zones where nocturnal animals need such protection), strong consideration should be made for 8 lower emission LEDs (e.g., 3000K or lower lighting with effective shielding). Strong consideration 9 also should be given to the use of filters to block blue wavelengths (as used in Hawaii), or to the 10 use of inherent amber LEDs, such as those deployed in Quebec. Blue light scatters more widely 11 (the reason the daytime sky is “blue”), and unshielded blue-rich lighting that travels along the 12 horizontal plane increases glare and dramatically increases the nighttime sky glow caused by 13 excessive light pollution. 14 15 POTENTIAL HEALTH EFFECTS OF “WHITE” LED STREET LIGHTING 16 17 Much has been learned over the past decade about the potential adverse health effects of electric 18 light exposure, particularly at night.21-25 The core concern is disruption of circadian rhythmicity. 19 With waning ambient light, and in the absence of electric lighting, humans begin the transition to 20 nighttime physiology at about dusk; melatonin blood concentrations rise, body temperature drops, 21 sleepiness grows, and hunger abates, along with several other responses. 22 23 A number of controlled laboratory studies have shown delays in the normal transition to nighttime 24 physiology from evening exposure to tablet computer screens, backlit e-readers, and room light 25 typical of residential settings.26-28 These effects are wavelength and intensity dependent, 26 implicating bright, short wavelength (blue) electric light sources as disrupting transition. These 27 effects are not seen with dimmer, longer wavelength light (as from wood fires or low wattage 28 incandescent bulbs). In human studies, a short-term detriment in sleep quality has been observed 29 after exposure to short wavelength light before bedtime. Although data are still emerging, some 30 evidence supports a long-term increase in the risk for cancer, diabetes, cardiovascular disease and 31 obesity from chronic sleep disruption or shiftwork and associated with exposure to brighter light 32 sources in the evening or night.25,29 33 34 Electric lights differ in terms of their circadian impact.30 Understanding the neuroscience of 35 circadian light perception can help optimize the design of electric lighting to minimize circadian 36 disruption and improve visual effectiveness. White LED streetlights are currently being marketed 37 to cities and towns throughout the country in the name of energy efficiency and long term cost 38 savings, but such lights have a spectrum containing a strong spike at the wavelength that most 39 effectively suppresses melatonin during the night. It is estimated that a “white” LED lamp is at 40 least 5 times more powerful in influencing circadian physiology than a high pressure sodium light 41 based on melatonin suppression.31 Recent large surveys found that brighter residential nighttime 42 lighting is associated with reduced sleep time, dissatisfaction with sleep quality, nighttime 43 awakenings, excessive sleepiness, impaired daytime functioning, and obesity.29,32 Thus, white LED 44 street lighting patterns also could contribute to the risk of chronic disease in the populations of 45 cities in which they have been installed. Measurements at street level from white LED street lamps 46 are needed to more accurately assess the potential circadian impact of evening/nighttime exposure 47 to these lights. 48 CSAPH Rep. 2-A-16 -- page 5 of 8 ENVIRONMENTAL EFFECTS OF LED LIGHTING 1 2 The detrimental effects of inefficient lighting are not limited to humans; 60% of animals are 3 nocturnal and are potentially adversely affected by exposure to nighttime electrical lighting. Many 4 birds navigate by the moon and star reflections at night; excessive nighttime lighting can lead to 5 reflections on glass high rise towers and other objects, leading to confusion, collisions and 6 death.33 Many insects need a dark environment to procreate, the most obvious example being 7 lightning bugs that cannot “see” each other when light pollution is pronounced. Other 8 environmentally beneficial insects are attracted to blue-rich lighting, circling under them until they 9 are exhausted and die.34,35 Unshielded lighting on beach areas has led to a massive drop in turtle 10 populations as hatchlings are disoriented by electrical light and sky glow, preventing them from 11 reaching the water safely.35-37 Excessive outdoor lighting diverts the hatchlings inland to their 12 demise. Even bridge lighting that is “too blue” has been shown to inhibit upstream migration of 13 certain fish species such as salmon returning to spawn. One such overly lit bridge in Washington 14 State now is shut off during salmon spawning season. 15 16 Recognizing the detrimental effects of light pollution on nocturnal species, U.S. national parks 17 have adopted best lighting practices and now require minimal and shielded lighting. Light pollution 18 along the borders of national parks leads to detrimental effects on the local bio-environment. For 19 example, the glow of Miami, FL extends throughout the Everglades National Park. Proper 20 shielding and proper color temperature of the lighting installations can greatly minimize these types 21 of harmful effects on our environment. 22 23 CONCLUSION 24 25 Current AMA Policy supports efforts to reduce light pollution. Specific to street lighting, Policy H-26 135.932 supports the implementation of technologies to reduce glare from roadway lighting. Thus, 27 the Council recommends that communities considering conversion to energy efficient LED street 28 lighting use lower CCT lights that will minimize potential health and environmental effects. The 29 Council previously reviewed the adverse health effects of nighttime lighting, and concluded that 30 pervasive use of nighttime lighting disrupts various biological processes, creating potentially 31 harmful health effects related to disability glare and sleep disturbance.25 32 33 RECOMMENDATIONS 34 35 The Council on Science and Public Health recommends that the following statements be adopted, 36 and the remainder of the report filed. 37 38 1. That our American Medical Association (AMA) support the proper conversion to community-39 based Light Emitting Diode (LED) lighting, which reduces energy consumption and decreases 40 the use of fossil fuels. (New HOD Policy) 41 42 2. That our AMA encourage minimizing and controlling blue-rich environmental lighting by 43 using the lowest emission of blue light possible to reduce glare. (New HOD Policy) 44 45 3. That our AMA encourage the use of 3000K or lower lighting for outdoor installations such as 46 roadways. All LED lighting should be properly shielded to minimize glare and detrimental 47 human and environmental effects, and consideration should be given to utilize the ability of 48 LED lighting to be dimmed for off-peak time periods. (New HOD Policy) 49 Fiscal Note: Less than $500 CSAPH Rep. 2-A-16 -- page 6 of 8 REFERENCES 1. Municipal Solid State Street Lighting Consortium. http://www1.eere.energy.gov/buildings/ssl/consortium.html. Accessed April 4, 2016. 2. Illuminating Engineering Society RP-8 – Guide to Roadway Lighting. http://www.ies.org/? 2014. Accessed April 4, 2016. 3. LED Lighting Facts–A Program of the United States Department of Energy. http://www.lightingfacts.com. Accessed April 5, 2016. 4. Lin Y, Liu Y, Sun Y, Zhu X, Lai J, Heynderickz I. Model predicting discomfort glare caused by LED road lights. Opt Express. 2014;22(15):18056-71. 5. Gibbons RB, Edwards CJ. 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Effect of different coloured luminous surrounds on LED discomfort glare perception. Lighting Research Technology. 2013;45(4):464-75. http://lrt.sagepub.com/content/45/4/464. Accessed April 5, 2016. 17. Scigliano E. Seattle’s new LED-lit streets Blinded by the lights. Crosscut. March 18, 2013. http://crosscut.com/2013/03/streetlights-seattle-led/. Accessed April 6, 2016. 18. Davis will spend $350,000 to replace LED lights after neighbor complaints. CBS Local, Sacramento;October 21, 2014. http://sacramento.suntimes.com/sac-news/7/138/6000/davis- will-spend-350000-to-replace-led-lights-after-neighbor-complaints. 19. Chaban M. LED streetlights in Brooklyn are saving energy but exhausting residents. NY Times; March 23, 2015. http://www.nytimes.com/2015/03/24/nyregion/new-led- streetlights-shine-too-brightly-for-some-in-brooklyn.html?_r=0. Accessed April 5, 2016. 20. Vos JJ. On the cause of disability glare and its dependence on glare angle, age and ocular pigmentation. Clin Exp Optom. 2003;86(6):363-70. 21. Stevens RG, Brainard GC, Blask DE, Lockley, SW, Motta, ME. Breast cancer and circadian disruption from electric lighting in the modern world. CA Cancer J Clin. 2014;64:207-18. 22. Evans JA, Davidson AJ. Health consequences of circadian disruption in humans and animal models. Prog Mol Biol Transl Sci. 2013;119:283-323. 23. Wright KP Jr, McHill AW, Birks BR, Griffin BR, Rusterholz T, Chinoy ED. Entrainment of the human circadian clock to the natural light-dark cycle. Curr Biol. 2013;23:1554-8. 24. Energy Savings Estimates of Light Emitting Diodes in Niche Lighting Applications. Building Technologies Program, Office of Energy Efficiency and Renewable Energy, U.S. Department of Energy. January 2011. http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/nichefinalreport_january201 1.pdf.Accessed April 7, 2016. 25. Council on Science and Public Health Report 4. Light pollution. Adverse effects of nighttime lighting. American Medical Association, Annual Meeting, Chicago, IL. 2012. 26. Cajochen C, Frey S, Anders D, et al. Evening exposure to a light-emitting diodes (LED)- backlit computer screen affects circadian physiology and cognitive performance. J Appl Physiol. 2011;110:1432-8. 27. Chang AM, Aeschbach D, Duffy JF, Czeisler CA. Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proc Natl Acad Sci USA. 2015;112:1232-7. CSAPH Rep. 2-A-16 -- page 8 of 8 28. Gooley JJ, Chamberlain K, Smith KA, et al. Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans. J Clin Endocrinol Metab. 2011;96:E463-72. 29. Koo YS, Song JY, Joo EY, et al. Outdoor artificial light at night, obesity, and sleep health: Cross-sectional analysis in the KoGES study. Chronobiol Int. 2016;33(3):301-14. 30. Lucas RJ, Peirson SN, Berson DM, et al. Measuring and using light in the melanopsin age. Trends Neurosci. 2014;37:1-9. 31. Falchi F, Cinzano P, Elvidge CD, Keith DM, Haim A. Limiting the impact of light pollution on human health, environment and stellar visibility. J Environ Manage. 2011;92:2714-22. 32. Ohayon M, Milesi C. Sleep deprivation/insomnia and exposure to street lights in the American general population. American Academy of Neurology Annual Meeting. April 15-21, 2016. Vancouver, BC. 33. Pawson SM, Bader MK. Led lighting increases the ecological impact of light pollution irrespective of color temperature. Ecological Applications. 2014;24:1561-68. 34. Gaston K, Davies T, Bennie J, Hopkins J. Reducing the ecological consequences of night-time light pollution: Options and developments. J Appl Ecol. 2012;49(6):1256–66. 35. Salmon M. Protecting sea turtles from artificial night lighting at Florida’s oceanic beaches. In- Rich C, Longcore T (eds.). Ecological Consequences of Artificial Night Lighting. 2006:141-68. Island Press, Washington, DC. 36. Rusenko KW, Mann JL, Albury R, Moriarty JE, Carter HL. Is the wavelength of city glow getting shorter? Parks with no beachfront lights record adult aversion and hatchling disorientations in 2004. Kalb H, Rohde A, Gayheart K, Shanker, K, compilers. 2008. Proceedings of the Twenty-fifth Annual Symposium on Sea Turtle Biology and Conservation, NOAA Technical Memorandum NMFS-SEFSC-582, 204pp. http://www.nmfs.noaa.gov/pr/pdfs/species/turtlesymposium2005.pdf 37. Rusenko KW, Newman R, Mott C, et al. Using GIS to determine the effect of sky glow on nesting sea turtles over a ten year period. Jones TT, Wallace BP, compilers. 2012. Proceedings of the Thirty-first Annual Symposium on Sea Turtle Biology and Conservation. NOAA Technical Memorandum NOAA NMFS-SEFSC-631:32p. Acknowledgement: The Council thanks George Brainard, PhD (Thomas Jefferson University); Richard Stevens, PhD (University Connecticut Health Center); and Mario Motta, MD (CSAPH, Tufts Medical School) for their contributions in preparing the initial draft of this report, and the commentary by Travis Longcore, PhD, on the ecological impact of nighttime electrical lighting. French Agency for Food, Environmental and Occupational Health & Safety, 14 rue Pierre et Marie Curie, 94701 Maisons-Alfort Cedex Telephone: +33 (0)1 49 77 13 50 - Fax: +33 (0)1 49 77 26 26 - www.anses.fr ANSES/PR1/9/01-06 [version e] code Ennov: ANSES/FGE/0037 ANSES Opinion Request No 2014-SA-0253 The Director General Maisons-Alfort, 5 April 2019 OPINION of the French Agency for Food, Environmental and Occupational Health & Safety on the “effects on human health and the environment (fauna and flora) of systems using light-emitting diodes (LEDs)” ANSES undertakes independent and pluralistic scientific expert assessments. ANSES primarily ensures environmental, occupational and food safety as well as assessing the potential health risks they may entail. It also contributes to the protection of the health and welfare of animals, the protection of plant health and the evaluation of the nutritional characteristics of food. It provides the competent authorities with all necessary information concerning these risks as well as the requisite expertise and scientific and technical support for drafting legislative and statutory provisions and implementing risk management strategies (Article L.1313-1 of the French Public Health Code). Its opinions are published on its website. This opinion is a translation of the original French version. In the event of any discrepancy or ambiguity the French language text dated 5 April 2019 shall prevail. On 19 December 2014, ANSES received a formal request from the Directorate General for Health, Directorate General for Labour, Directorate General for Risk Prevention and Directorate General for Competition, Consumer Affairs and Fraud Control to undertake an expert appraisal assessing the effects on human health and the environment (fauna and flora) of systems using light-emitting diodes (LEDs). 1. BACKGROUND AND PURPOSE OF THE REQUEST The objective of the expert appraisal undertaken by ANSES was to update knowledge on the health effects related to exposure to lighting systems using LEDs. The request focused more specifically on assessing the risks associated with exposure to LED systems for the general population and workers, distinguishing between the different types of applications of LED lighting systems and objects (domestic lighting, professional uses, vehicle lights, toys, screens, etc.) and taking into account real situations of exposure. Moreover, a review of the potential environmental risks associated with these systems throughout their life cycle was requested. Page 2 / 24 ANSES Opinion Request No 2014-SA-0253 Pursuant to Directive 2005/32/EC on the eco-design of energy-using products, known as the “EuP” Directive, the planned withdrawal of incandescent lamps (spread out between 2009 and 2012) and conventional halogen lamps (set for September 2018) from the lighting market has led to a sharp increase in LED lighting systems on the consumer market, thus increasing the population's exposure to lighting systems using this technology. The scope of LED systems has expanded: it now includes not only a large number of applications for professional use, but also applications for public use including displays and signs, as well as certain objects and devices (toys, decorative objects, etc.), backlighting in screens (mobile telephones, tablets, televisions, etc.) and indoor and outdoor lighting. When publishing its first Opinion on the health effects associated with LEDs (ANSES’s collective expert appraisal report published in 20101), the Agency drew attention to the retinal toxicity of blue light. Indeed, LEDs are unique in that they emit light rich in short wavelengths: this is known as blue- rich light. On this occasion, ANSES issued recommendations relating, among other things, to the placing on the market of LEDs and the provision of information to consumers. The potential health effects associated with exposure to the light emitted by LEDs are now better documented. Since the Opinion issued by the Agency in 2010, new experimental data, obtained in animals in particular, have been published regarding the phototoxicity associated with long-term exposure to blue light. New data have also been published relating to the disruptive effects of blue light on the biological clock, glare, and the health effects associated with temporal light modulation (light-intensity fluctuations in lighting that may be visually perceived depending on frequency). Regarding the possible effects on the environment, there are data that raise questions about potentially induced imbalances in ecosystems, which may have consequences for fauna and flora as well as for humans and human health. Adding or substituting artificial light to/for natural sunlight raises the issue of the potential health effects this may cause, due to the accumulation or modification of the lighting environment. Over the past few decades, humans have considerably increased their exposure to blue light in the evening with artificial lighting and backlights rich in blue light. Previously, the lighting systems used had tended to be yellow-orange in colour (candles, incandescent lamps). The update of the expert appraisal considered all of the effects on human health and the environment (fauna and flora) that could be associated with exposure to the light of LED lamps. 2. ORGANISATION AND METHODOLOGY OF THE EXPERT APPRAISAL This expert appraisal falls within the sphere of competence of the Expert Committee (CES) on “Physical agents, new technologies and development areas”. The Agency mandated a Working Group of experts, entitled “Health effects of LED systems”, to undertake this expert appraisal under the leadership of the CES. Working Group The Working Group was formed following a public call for applications issued on 28 April 2015. The experts in this group were selected for their scientific and technical skills in the are as of physics, optical radiation metrology, vision, ophthalmology, chronobiology, biology, the environment and lighting regulations. The Working Group was created in September 2015. It met 25 times in plenary sessions between September 2015 and May 2018. 1 https://www.anses.fr/fr/system/files/AP2008sa0408.pdf . Page 3 / 24 ANSES Opinion Request No 2014-SA-0253 External contributions To make up for the lack of data relating to the characterisation of exposure to LED systems, three studies were financed by the Agency. Characterisation of the artificial lighting systems available on the French market First of all, a research and development agreement was drawn up between the Agency and the French National Consumer Institute (INC) in order to conduct an updated comparative study of the technical properties of various lighting systems available on the market. Documentation of exposure to light in populations The implementation of a second study was entrusted to the French Scientific and Technical Centre for Building (CSTB), in order to characterise the population’s exposure to various artificial lighting and LED systems, in real conditions of exposure. A software program developed to that end enabled light exposure to be assessed for several exposure scenarios (children, workers, elderly people, etc.). Assessment of blue-light protection systems intended for the general public A third study was undertaken with the CSTB to assess the blue-light filtration capacities of protective devices intended for the general public (screen filters, treated lenses, blocking glasses, software protection). Collective expert appraisal The methodological and scientific aspects of the expert appraisal work were regularly submitted to the CES. The report produced by the Working Group takes account of the observations and additional information discussed with the CES members. This expert appraisal was therefore conducted by a group of experts with complementary skills. It was carried out in accordance with the French Standard NF X 50-110 “Quality in Expertise Activities”. Interests declared by the experts were analysed by ANSES before they were appointed and throughout their work in order to prevent risks of conflicts of interest in relation to the points addressed in the expert appraisal. The experts’ declarations of interests have been made public via the ANSES website: http://www.anses.fr Expert appraisal methodology Literature search and analysis The collective expert appraisal was mainly based on a critical analysis and summary of the data published in the scientific literature (articles, reports, etc.). The literature search was thus undertaken for the period from January 2010 to July 2017. The results of the studies financed by ANSES to supplement knowledge of protective devices and exposure to artificial light in populations were taken into account in the expert appraisal. The Working Group also interviewed external experts and figures, as well as representatives from the lighting industry and environmental protection associations, inviting them to contribute information and data supplementing the data available for the expert appraisal. Assessment of the level of evidence for health effects For each studied health effect, the results of the available studies undertaken in humans on the one hand and animals on the other hand were considered separately to characterise the evidence provided regarding the connection between exposure to LED light, in particular blue-rich light, and the occurrence of the health effect. In the end, the evidence for humans and animals was combined in order to establish an overall assessment of the level of evidence for the health effect of exposure to LED light, classifying it into one of the following categories: proven effect; probable effect; Page 4 / 24 ANSES Opinion Request No 2014-SA-0253 possible effect; it is not possible to conclude from the available data as to whether or not there is an effect; probably no effect. Characterisation of exposure The lack of literature data dealing with the population's exposure to LED technologies led ANSES to finance specific measurement campaigns, in particular to describe the type and quantity of light emitted by LED systems used on a daily basis (e.g. lamps, objects featuring LEDs, vehicle headlamps, and computer, tablet and mobile telephone screens). Exposure to blue-rich light, especially via LED systems, was assessed as part of life scenarios, thanks to measurements taken in situ in specific environments. Table 1 in the Annex summarises the main physical quantities used in particular to quantify emissions and exposure in the area of lighting. Assessment of risks to human health By combining the assessment of the level of evidence for health effects obtained from the analysis of the scientific articles and the data from the exposure scenarios, the expert appraisal sought to characterise the potential risks to humans associated with exposure to systems using LEDs . Thus, the Working Group classified risks of occurrence of health effects in humans into four levels as defined below: high risk; moderate risk; low risk; no predictable risk. The collective expert appraisal report describes the methodology used to assess the level of evidence for the studied effects as well as the qualitative assessment of the related risks. 3. ANALYSIS AND CONCLUSIONS OF THE CES The Expert Committee on “Physical agents, new technologies and development areas” adopted the collective expert appraisal work and its conclusions and recommendations as described in this summary at its meeting of 23 November 2018 and informed the ANSES General Directorate accordingly. 3.1 Specific characteristics of the light emitted by LED lamps The specific characteristics of LEDs are related to the type of radiation emitted on the one hand and to the physical properties of the lamps using this technology on the other hand. Firstly, the light spectrum emitted by LEDs can be richer in blue light (there are lamps with very high colour temperatures2 of above 6000 K, supplying extremely blue-rich light) and poorer in red light than most other natural and artificial light sources. The additional blue light in the LED spectrum compared to other light sources (spectral imbalance) raises the issue of the effects of light from LED lamps on the retina (phototoxic effects) and on circadian rhythms and sleep (melanopic effects). The lack of red light in LEDs may also deprive individuals of the potential photoprotective effects of this 2 Colour temperature is a way to characterise light sources in comparison with an ideal material emitting light only under the influence of heat. The temperature of the black body whose visual appearance is closest to that of the light source is expressed in Kelvins (a unit of the international system whose symbol is K). Page 5 / 24 ANSES Opinion Request No 2014-SA-0253 radiation, especially during the physiological emmetropisation3 process that takes place during childhood. Secondly, due to their high luminance4 and small emission areas, LED lights can produce more glare than light emitted by other technologies (incandescent, compact fluorescent, halogen lamps, etc.). This can especially be the case with LED matrices (small LED aggregates on the same base), LED spotlights, vehicle lights and hand-held lamps. Lastly, LEDs are highly reactive to current fluctuations. Thus, variations in light intensity can appear depending on the quality of the power supply. These phenomena are grouped under the term “temporal light modulation”. Humans can suffer from the negative effects of these variations, whether or not they are visually perceptible. 3.2 Changes in regulations and standards since 2010 3.2.1 Regulations and standards relating to the phototoxicity of light o Exposure limits Regarding exposure to optical radiation and photobiological safety in particular, the International Commission on Non-Ionizing Radiation Protection (ICNIRP) published new guidelines on exposure to visible and infrared optical radiation in 2013 (ICNIRP, 2013)5. The blue-light exposure limits, which remained the same as those proposed in 1997, only involved acute exposure (single, continuous exposure for less than eight hours). o Regulatory texts governing uses of devices, lighting products and artificial optical radiation applicable to LEDs in particular - General population The European “Low Voltage” Directive (2014/35/EU) aims to ensure that the electrical equipment on the European market meets requirements providing a high level of protection of health and safety. Manufacturers can rely on their products’ compliance with harmonised standards to meet the essential requirements of this directive. However, portable lighting systems (hand-held lamps, head torches) do not fall within the scope of the Low Voltage Directive. Nevertheless, they use LED sources that can have very high light intensities. Similarly, for vehicle lighting (exterior lamps), there are no regulations intended to guarantee photobiological safety, for example by limiting the emission intensities of lamps or human exposure. The case of toys using LEDs is not adequately covered by the European Directive on the safety of toys (2009/48/EC), since it refers, for health-related risks, to the standard on the safety of laser products (IEC 608251-1), which is not suited to LED lighting. This standard also does not consider the fact that the eyes of children are more sensitive to blue light due to a clearer lens. - Workers European Directive 2006/25/EC of 5 April 2006 on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (artificial optical radiation - AOR) includes risk related to blue light. For this specific risk, it relies on the ICNIRP guidelines 3 Emmetropisation is the process of normal ocular development leading to the formation of a sharp image on the retina. 4 Luminance is a quantity corresponding to the perceived brightness of an area. A very bright area has high luminance, while a completely black area has zero luminance. 5 ICNIRP Guidelines on Limits of Exposure to Incoherent Visible and Infrared Radiation, published in: Health Physics 105(1):74‐96;2013. Page 6 / 24 ANSES Opinion Request No 2014-SA-0253 published in 1997. In France, the AOR Directive was transposed into the Labour Code by decree in 20106. A ministerial order from 20167 defines risk assessment methods based on European standards relating to human exposure to optical radiation. o Standards The standards relating to the assessment of photobiological safety (CIE S009, IEC 62471 and NF EN 62471) refer to the ICNIRP limit values and propose that lamps be classified into risk groups: risk group 0 (no risk), risk group 1 (low risk), risk group 2 (moderate risk) and risk group 3 (high risk). In 2014, a technical report (IEC TR 62778:2014) accompanying the NF EN 62471 standard was published by the International Electrotechnical Commission (IEC). This report describes a method for assessing the photobiological risk group in the case of blue light. It includes several of ANSES's recommendations, in particular a procedure for transferring the risk group of an individual LED to an LED module and a finished product (luminaire), as well as the specification of a minimum viewing distance for people exposed to light sources in risk group 2 or higher. Since 2015, harmonised lighting standards have included photobiological safety requirements8 limiting the possible effects of radiation on eyes and skin. A distinction is made between lamps on the one hand and luminaires9 powered by the electrical grid (non-portable luminaires) on the other hand. Regarding lamps, the requirements consist in limiting the photobiological risk group to level 0 or 1 in accordance with the NF EN 62471 standard. Regarding non-portable luminaires, there are no limits on the risk group; there is merely an obligation to inform consumers in the event of a risk group of 2 or higher10. 3.2.2. Regulations and standards relating to other health effects There are currently no specific regulations dealing with effects related to circadian rhythm disruption, glare, or temporal light modulation. o Circadian rhythm disruption In 2004, the International Commission on Illumination (CIE) published a document, updated in 2009 (CIE, 2009)11, defining spectral sensitivity curves for melanopsin12-containing retinal ganglion cells. o Glare The standards relating to glare have not changed since 2010. The lighting industry uses the glare ratings, in particular the Unified Glare Rating (UGR), defined by the CIE. The UGR formula was initially developed for interior luminaires equipped with fluorescent tubes. The validity of extending the use of the UGR to LED lighting systems is questionable. The CIE’s 2013 publication, “Review of 6 Decree no. 2010-750 of 2 July 2010 concerning the protection of workers from risks due to artificial optical radiation, JORF no. 0153 of 4 July 2010, page 12149, text no. 11. 7 Ministerial Order of 1 March 2016 concerning methods for assessing risks resul ting from occupational exposure to artificial optical radiation, JORF no. 0066 of 18 March 2016, text no. 30. 8 These requirements are specified in Standard NF EN 62560– Self-ballasted LED-lamps for general lighting services by voltage > 50 V – Safety specifications, and Standard NF EN 60598-1 Luminaires – Part 1: General requirements and tests (general part common to all luminaires). 9 A luminaire is a combination of a lamp and a decorative element or a combination of several lamps. 10 For non-portable luminaires belonging to risk group 2, the safety standards (for example, Standard NF EN 60598-1 on general requirements for luminaires) require the labelling of the threshold distance and the following statements: “the luminaire should be positioned so that prolonged staring into the luminaire at a distance closer than x m is not expected” and “do not stare at the light source”. 11 CIE 158:2009: Ocular Lighting Effects on Human Physiology and Behaviour. 12 Melanopsin is a photopigment contained in the retina and photosensitive ganglion cells. Page 7 / 24 ANSES Opinion Request No 2014-SA-0253 Lighting Quality Measures for Interior Lighting with LED Lighting Systems” (CIE 205:2013), concluded that a new assessment system for glare was necessary for LED lighting. o Health effects related to temporal light modulation Since 2015, most standardisation organisations have produced new standards and technical documents or updated those already existing to describe phenomena involving temporal light modulation. However, there are no European or French regulations limiting the temporal modulation of the light emitted by lamps and luminaires. The regulations on lighting (in terms of eco-design and labelling) are currently being revised by the European Commission; aspects involving temporal light modulation are expected to appear in the text. 3.3 Human health risks associated with exposure to LED light The human health risks associated with exposure to LED light are mainly due to the spectral composition of the light on the one hand and temporal light modulation on the other hand. Of the health effects of LEDs, those related to blue light, such as phototoxicity and circadian rhythm disruption, are highly dependent on the exposed person's age. Indeed, the lens acts as a blue-light filter in the eye and its transmittance changes considerably with age. Children are born with a clear lens, letting through all blue light, and reach an optimum filtration rate around the age of 20. A person over the age of 60 has a blue-light filtration rate around twice that of a 20-year-old. There is a distinction between light sources (or light objects) emitting blue light and objects that have a blue colour. In the first case, the light spectrum received by the eye is (often) enriched with blue light. The amount of light received by the retina in the blue band can be large and have phototoxic effects on the eye and a disruptive effect on biological rhythms. In the second case, the blue colour of the objects and surrounding materials, with conventional lighting, is due to the reflection of part of the spectrum and ends up absorbing some of the light. The intensity of the light source is diminished overall, and the perception of colour can have soothing effects. 3.3.1. Circadian rhythm disruption, sleep disruption, and effects on cognitive performance and vigilance levels 3.3.1.1 Hazard characterisation o Circadian rhythm disruption The light received by the retina has two main effects: it enables the formation of images (visual effect) and gives the body an idea of the time of day (non-visual effect). This non-visual effect involves melanopsin-containing retinal ganglion cells (mRGCs) that have specific spectral sensitivity: they are strongly stimulated by blue light, with peak sensitivity around 480 nm. These mRGCs send their messages to the suprachiasmatic nuclei of the hypothalamus, the seat of the central circadian clock. This central clock distributes the message to the rest of the body, in order to synchronise all of its biological functions with the day/night cycle. Thus, the adequate regulation of mRGC activity is essential for keeping the biological rhythms of organisms synchronised with their environment. The “melanopic” wavelength band (turquoise blue, 480-490 nm) is thus related to effects on circadian rhythmicity. The central biological clock determines the production of a hormone, called melatonin, whose secretion begins in the evening, around two hours before bedtime, and then reaches a peak towards the middle of the night before returning to very low and even undetectable levels in the morning and for the rest of the day. Thus, the daily rhythm of circulating melatonin concentrations is a reliable indicator of the biological clock's activity and disruptions. The effective synchronisation of the central circadian clock, and thus of the biological functions that depend on it, in particular wake/sleep rhythms, requires high light intensity during the day and total darkness at night. Current lifestyle habits, especially in urban environments, are increasingly tending to disrupt the natural daily light/dark cycle, with time spent indoors during the day (accompanied by Page 8 / 24 ANSES Opinion Request No 2014-SA-0253 a decrease in light intensity) and exposure to multiple light sources (lighting, screens) in the evening and at night. There have been many different publications studying the disruption of circadian rhythms related to exposure to light in the evening or at night. The results of several experimental studies conducted in humans, during which people were subjected to blue-rich light from artificial lighting or screens (computers, telephones, tablets, etc.), were consistent and indicated that nocturnal melatonin synthesis was delayed or inhibited even by very low exposure to blue-rich light. The degree of circadian disruption seems to depend on the light intensity, the time and duration of exposure, and the individual's history of exposure to light during the day. However, a value of around 10-40 lux or lower (a very low level that can be largely exceeded with domestic lighting) is sufficient to observe an impact on the circadian clock (illustrated by the suppression of noctu rnal melatonin secretion). In conclusion, in light of the sufficient evidence provided by studies undertaken in humans, circadian rhythm disruption induced by exposure to blue-rich light during the evening or at night is considered as proven. Furthermore, experimental studies in animals have demonstrated that circulating melatonin in a mother crosses the placental barrier and enters the foetal circulation, which possesses melatonin receptors. Thus, maternal melatonin can impact foetal development, in particular the establishment of the circadian system. At night, maternal exposure to light modifies melatonin levels and induces a prenatal effect that appears to have consequences lasting into adulthood (effects on circadian rhythms, metabolic effects, etc.). It can reasonably be assumed that in humans, the effects of modern lighting at night on maternal melatonin secretion negatively impact in utero foetal development. The disruption of circadian rhythms is also associated with other health effects13 (disruption of sleep quality and quantity, metabolic disorders, increased risk of cancer - especially breast cancer, cardiovascular diseases, effects on mental health). However, the direct connection between exposure to blue-rich light in the evening or at night and the occurrence of these health effects, while strongly suspected, has not been proven to date in humans. o Sleep disruption Most of the available scientific studies show that blue light alters sleep regulation via circadian disruptions. The evidence provided by studies undertaken in humans is sufficient to conclude that exposure to blue-rich light during the evening has a proven effect on sleep onset latency and the duration and quality of sleep. o Effects on vigilance levels and cognitive performance Several studies have shown that exposure to blue light (from LEDs in particular) in the day or at night improves cognitive performance and enhances vigilance levels. A number of studies have focused on the effects of lighting, especially blue light, on the performance of night workers. The objective has been the short-term optimisation of vigilance and the reduction of sleepiness in order to reduce industrial and traffic accidents and enhance performance and productivity. These are major challenges for modern societies. However, the issue of potential health effects, due to a possible increase in the phototoxicity of light at night, has yet to be defined. 13 Assessment of the health risks associated with night work, ANSES collective expert appraisal report, June 2016. Page 9 / 24 ANSES Opinion Request No 2014-SA-0253 3.3.1.2 Characterisation of LED light sources and exposure Exposure to blue light was studied in the “melanopic” band (turquoise blue, 480-490 nm) for effects on melatonin and circadian rhythms. The quantity of blue light emitted by an LED object can be estimated based on its colour temperature, expressed in Kelvins (K), and its level of illuminance on a surface, expressed in lux (especially at the plane of the eye). Measurement campaigns undertaken to describe the type and quantity of light emitted by LED systems showed that light emitted by screens of televisions, computers, mobile telephones or tablets had a low level of illuminance but was rich in blue light. LED computer screens had colour temperatures ranging from 4500 K to 6900 K and illuminance values at the plane of the eye ranging from 20 to 60 lux. For the LED screens of smartphones and electroni c tablets, colour temperatures ranged from 4100 K to 7000 K and illuminance values at the plane of the eye from 2 to 10 lux. As for domestic lighting, the LED lamps available on the market can offer colour temperatures ranging from 2500 K (low level of blue light) to 6900 K (very high level of blue light). Regarding human exposure to blue light in the melanopic band, no data were identified in the scientific literature. The light exposure scenarios developed for this expert appraisal, representing typical living conditions for various populations, showed that exposure in the melanopic band was similar with LED lighting with moderate levels of blue light (colour temperatures ranging from 2700 K to 4000 K), compact fluorescent lamps and halogen lamps. Nevertheless, with life scenarios including “worst case” situations (LEDs with very high levels of blue light, colour temperatures of around 6500 K), exposure in the melanopic band was higher compared with other lighting technologies, regardless of the population in question. Moreover, the use of LED screens and objects is likely to increase exposure to blue light in the melanopic band. 3.3.1.3 Health risk assessment Based on the available data, the risk of circadian rhythm disruption or sleep disruption related t o exposure to LEDs cannot be precisely quantified. Nevertheless, in light of the above and based on a qualitative approach, the Working Group's experts consider that the risk of circadian disruption associated with exposure to blue-rich LED lights in the evening or at night is high. In particular, exposure before bedtime to LED lighting or screens from televisions or communication technologies enriched with blue light is likely to adversely affect sleep duration and quality and impact cognitive functions. 3.3.1.4 Susceptible population groups The available studies have shown even stronger effects of delayed bedtimes, due to the impairment of non-visual functions, in particular melatonin suppression, in children, adolescents and young adults (before the age of 20). An obvious factor is the higher lens clarity of young people, causing more light to pass through than for adults. In addition to the widespread use of devices with LED screens by adolescents, the behavioural, hormonal and circadian changes occurring in this phase of life (increase in the endogenous period of the circadian cycle) are probably also involved. More generally, several population groups were identified as being more specifically susceptible to the risk of circadian and sleep disruption associated with exposure to LEDs: infants, children, adolescents and young adults (due to a clear lens); aphakic (with no lens) and pseudophakic (with an artificial lens) individuals; pregnant women (potential health effects on the unborn child); night workers14; 14 Night workers are particularly susceptible since their exposure to LED lighting is potentially high. Page 10 / 24 ANSES Opinion Request No 2014-SA-0253 people with ocular diseases or anomalies, and people with sleep disorders. 3.3.2 Ocular effects and diseases 3.3.2.1 Hazard characterisation Phototoxicity is a mechanism of light-induced cellular damage that can lead to cell death. Exposure to intense and acute light is phototoxic since it causes the irreversible loss of retinal cells, which can lead to partial and permanent (scotoma15, decrease in visual field, reduced resolution) or total (blindness) vision loss. Chronic exposure to low-intensity phototoxic lights speeds up the ageing of retinal tissues, potentially leading to vision loss and degenerative diseases such as age-related macular degeneration (ARMD). Regarding the toxic effects of blue-rich light on the eye, the available data show that: the retinal phototoxicity of acute (for less than eight hours) exposure to blue-rich light is proven; the contribution of chronic (for several years) retinal exposure to blue-rich light to the occurrence of ARMD is proven; since the long-term ocular effects of artificial lighting have not been studied to date, these conclusions are based on epidemiological studies taking into account exposure to sunlight (blue-rich light); in addition to the received phototoxic dose, the time of exposure plays a major role. Some experimental studies, currently limited to animals, have demonstrated increased retinal vulnerability to phototoxicity at night, due to a daily photosensitivity rhythm and disruptive effects on the endogenous retinal clock. Numerous studies have shown that the exposure limits (ELs) selected by ICNIRP for the retinal toxicity of light are not sufficiently protective. Some authors (Hunter et al., 2012)16 have considered that to be protective, these ELs would need to decrease by a factor of 20. In addition, the expert appraisal provided an opportunity to highlight that these ELs are only proposed for acute exposure (for less than eight hours) and ignore the issue of long -term exposure. The experts also mentioned the existence of new UV-LED systems17 that may pose phototoxic risks. Furthermore, the review of the scientific literature on myopia and Sjögren syndrome 18 led to the following conclusions: the effect of blue-rich light on myopia is possible (whether positive or negative); the effect of blue-rich light on the occurrence of Sjögren syndrome is possible. 3.3.2.2 Characterisation of LED light sources and exposure Exposure to blue light was studied in the “phototoxic” band (deep blue, 450-470 nm). The physical measurements taken as part of this expert appraisal showed that some of the tested LED lighting devices (hand-held lamps, head torches, toys and certain vehicle lights - especially dipped-beam headlamps, etc.) emit blue-rich light (devices classified in risk group 2, maximum anticipated exposure duration of less than 100 s, according to the exposure limits defined by 15 A break in the field of vision due to insensitive retinal areas. 16 Hunter, Jennifer J., Jessica I. W. Morgan, William H. Merigan, David H. Sliney, Janet R. Sparrow, and David R. Williams. 2012. The Susceptibility of the Retina to Photochemical Damage from Visible Light. Progress in Retinal and Eye Research 31 (1): 28-42. 17 New generation of LEDs whose blue-light peak is shifted to the ultraviolet region (around 410 nm). 18 Sjögren syndrome involves lacrimal system dysfunction causing dryness on the surface of the eye (cornea, conjunctiva, etc.). This syndrome is characterised by ocular discomfort with tingling sensations or an impression of a foreign body in the eye. Page 11 / 24 ANSES Opinion Request No 2014-SA-0253 ICNIRP). Some telephone screens and electronic tablets using LED technology emit fairly low- intensity but systematically blue-rich light. It should also be noted that decorative blue LEDs have emerged on the market and that LEDs are being used in a growing number of applications (e.g. in agricultural lighting systems, to light up aquariums, etc.). Adding artificial lighting to natural lighting is likely to modify the ocular doses received by the cornea and retina in the phototoxic band (up to a 50% increase). Comparing the contributions of LED lighting systems and other lighting technologies to overall human exposure according to defined scenarios produced the following results: in general, LED lighting systems increase the imbalance in wavelengths in favour of blue light compared to red light, in comparison with other lighting systems, at the same colour temperature; exposure in the phototoxic band is even higher when colour temperature is high (blue-rich light), regardless of the lighting technology (LED or otherwise). Regarding the phototoxic dose received by the retina, the results of the examination of exposure scenarios showed that LEDs were only different from other technologies in the “worst case” scenario, in which the LED lighting systems used had very high levels of blue light (high colour temperatures of around 6500 K). Even so, the experts underline that this “worst case” scenario can correspond to the situations of certain people with very low exposure to natural light who are subjected to blue-rich lighting in their workplace (for example, in the winter, it is dark out in the morning when leaving home and in the evening when returning home, and the daytime is spent in an environment lit exclusively by artificial blue-rich lighting). The Working Group's experts would like to point out the significant commercial development of small bare decorative LEDs emitting blue light (string lights, ambient lighting, etc.). These LEDs can increase exposure in the phototoxic band, even at low luminance levels. Indeed, the photons of blue light have higher energy than the photons associated with longer wavelengths. They can therefore induce photochemical reactions similar to those caused by ultraviolet radiation. Moreover, human visual perception is less sensitive to blue light. High energy levels in blue light can therefore be received by the retina without creating a strong visual sensation. Since this blue-coloured light does not necessarily create glare, it can be stared at over a long period, especially by children. 3.3.2.3 Health risk assessment Based on the available data, the risk of ocular diseases occurring in relation to exposure to LEDs cannot be precisely quantified. However, in light of the above and based on a qualitative approach, the experts consider that the risk of acute toxicity associated with “warm white” (low colour temperature) LEDs for domestic use is low. It should be noted that lighting devices belonging to risk group 2 (hand-held lamps, head torches, toys and certain vehicle lights) are available on the market. The risk of ocular diseases occurring in relation to exposure to these devices is higher, especially for susceptible population groups. Similarly, objects specifically emitting blue light (e.g. decorative LEDs), even at low intensities, can increase exposure in the phototoxic band. Due to the lack of data on the chronic effects of low-dose exposure to cool light (screens, for example), the risk level associated with chronic exposure to blue-rich LEDs cannot currently be assessed. 3.3.2.4 Susceptible population groups Regarding the risk of ocular diseases, several susceptible population groups were identified based on the data from the literature: infants, children, adolescents and young adults (clear lens); aphakic (no lens) and pseudophakic (artificial lens) individuals; Page 12 / 24 ANSES Opinion Request No 2014-SA-0253 people with ocular diseases (dry eye, ARMD, glaucoma, retinopathy, etc.); people with motor or cognitive disorders reducing their avoidance or decision-making capacities in the event of overly intense light; people taking photosensitising medications or exposed to photosensitising pollutants; night workers19 and any other professionals with potentially high exposure to LED lighting (surgeons, dentists, lighting professionals, lighting distributors, performing artists, people working in sport facilities, people working in agri-food facilities using LEDs (greenhouses, aquaculture), etc.). 3.3.3 Glare and visual comfort 3.3.3.1 Hazard characterisation Glare corresponds to viewing conditions in which a person experiences discomfort or is less capable of perceiving details or objects, due to an unfavourable luminance distribution or an extreme contrast. A distinction should be made between disability glare, which reduces the subject's visual capacities and performance, and discomfort glare, which causes the subject to experience a sensation of discomfort but does not cause a decline in visual performance. Several factors modulate glare-related disability. These include the quantity of light sent into the eye by the source itself as well as the distance from the glare source and the observer’s age. However, the spectral composition of light does not modify the disability glare phenomenon. It appears that the multiple visible point sources in luminaires (LED matrices) considerably increase discomfort. All studies have consistently shown that (1) non-uniform sources produce more glare than uniform sources, even with moderate luminance, and (2) the higher the contrast, the greater the sensation of discomfort. Moreover, since the scattering of light in ocular environments increases with age, discomfort also increases. Regarding both LED sources and “conventional” light sources, colour temperature does not seem to be a determinant of visual comfort. However, at the same colour temperature, the spectral composition and especially the blue-light enrichment of the spectrum has probable consequences on visual discomfort. The long-term effects of repeated glare are not known to date. Furthermore, there is a high level of inter-individual variability in the general population as to the assessment of glare situations. 3.3.3.2 Characterisation of LED light sources and exposure Luminance (expressed in cd/m² 20), measured when directly viewing a light source from a short distance, enables the level of glare potentially produced by that light source to be assessed. The LED lamps tested for this expert appraisal had disparate luminance levels; some of them, especially those in LED spotlights, produced a very high level of glare. Another aspect of visual comf ort is related to colour rendering. The colour rendering index (CRI) represents a light's capacity to faithfully render a colour. A CRI of 100 refers to an optimum light, and it is recognised that a CRI is deemed acceptable above 80. LED lamps do not yet offer the capacities of halogen lamps, which have CRIs close to 100, but their performance is similar to that of compact fluorescent lamps, sometimes with measured CRIs greater than 80. Compared to the context of ANSES's previous expert appraisal published in 2010, LED technology now offers higher-quality colour rendering. 3.3.3.3 Health risk assessment Based on the available data, the risk of visual discomfort or disability glare related to exposure to LEDs cannot be precisely quantified. However, in light of the above and based on a qualitative approach, the experts consider that certain lighting devices including LEDs (hand-held lamps, 19 Night workers are particularly susceptible since their exposure to LED lighting is potentially high. 20 cd/m²: candela per square metre. Page 13 / 24 ANSES Opinion Request No 2014-SA-0253 vehicle lights, LED spotlights, LED matrices, etc.) can pose a high risk of glare. Moreover, while certain LED lamps have better colour rendering than they did a few years ago, this can still be improved. 3.3.3.4 Susceptible population groups Age is a factor aggravating the risk of glare associated with LEDs, both during the day and at night. Deterioration of vision accelerates after the age of 60, at varying rates depending on the individual. The stray light generated around sources increases considerably with age, lowering the perception of object contrast and therefore visual performance. Subjects with migraine seem to be specifically susceptible to the glare caused by certain irregularities in the spectral distribution of light energy. 3.3.4 Skin effects 3.3.4.1 Hazard characterisation Blue light may have adverse effects on the skin, accelerating ageing and delaying healing processes, whereas exposure to wavelengths of 590 to 700 nm (red light) appears to have opposite effects. The experts conclude that the effect of exposure to blue-rich light on the occurrence of skin diseases is possible. Moreover, the delayed carcinogenic effect (melanoma induction) induced by blue-light LED phototherapy used for the treatment of neonatal jaundice should be given special attention. Of the five studies undertaken to assess the risk of developing benign or malignant melanocytic lesions following blue-light neonatal phototherapy, three showed an increased number of common or atypical naevi in exposed children. 3.3.4.2 Characterisation of LED light sources and exposure There are no exposure data specifically dealing with the skin effects of b lue-light emissions. Nevertheless, the photobiological risk group provides an idea of the quantity of blue light emitted by LED lighting (see § on the characterisation of exposure for ocular diseases). 3.3.4.3 Health risk assessment Based on the available data, the potential risks to the skin related to exposure to LEDs cannot be quantified. Based on a qualitative approach and considering the exposure levels associated with the domestic use of LED lighting as well as the limited skin penetration depth of blue-light optical radiation, the experts consider that the risk of skin diseases occurring in relation to exposure to blue light from LEDs is low. 3.3.4.5 Susceptible population groups The experts identified some potentially susceptible population groups: newborns in the event of blue-light LED phototherapy prescribed to treat neonatal jaundice; people with certain skin diseases (epithelial lesions, wounds, etc.); these people appear to have an increased risk of skin lesions developing or worsening during exposure to blue light. 3.3.5 Other disorders (migraines, headaches, visual fatigue, accidents, epilepsy attacks) 3.3.5.1 Hazard characterisation The temporal modulation of a lighting system is primarily characterised by its modulation frequency and the corresponding modulation rate, expressed as a percentage of the light intensity (values ranging from 0% to 100%). Depending on its frequency, this modulation may or may not be perceptible by the human visual system. Three separate visual effects (conscious perception of modulation) have been described: flicker, the stroboscopic effect and the phantom array effect. Health effects can be directly induced by these visual effects or occur with no conscious perception Page 14 / 24 ANSES Opinion Request No 2014-SA-0253 of any modulation. The health effects that can result from the conscious or unconscious perception of modulation are epilepsy attacks, traffic accidents, accidents related to the use of machin es, migraines, headaches and visual fatigue. Effects such as headaches, migraines and visual fatigue can be associated with temporal modulation frequencies between 80 and 120 Hz. The related evidence provided by studies is limited for humans. Phenomena such as the stroboscopic effect (apparent immobility or slowing of a moving object) and the phantom array effect (persistence of an image during a visual saccade) can occur at high modulation frequencies (greater than around 80 Hz). In an industr ial or domestic context, it is likely that the stroboscopic effect could affect safety during the use of machines or tools. Temporal light modulation can also be associated with the triggering of attacks in people with epilepsy. However, the modulation frequencies of the LED lamps and luminaires available on the market are too high to trigger attacks in these individuals. Nevertheless, there is a possibility of attacks being triggered in the population of epileptic subjects during exposure to LED lamps or luminaires with abnormal temporal modulation (defective products or incompatibility with the controller). Moreover, certain self-contained lighting devices on bicycles (recharged by magnetic induction) are very strongly modulated (100% modulation) at frequencies varying with the cyclist's speed. At certain speeds, the temporal modulations are located around 15 Hz, in the most critical band for the triggering of epilepsy attacks. In all of these situations, temporal light modulation is associated with visual discomfort and a decrease in visual efficiency, especially at workstations in occupational settings. 3.3.5.2 Characterisation of LED light sources and exposure Results from the scientific literature dealing with the temporal modulation of LED lamps were aggregated with measurements taken in the context of this expert appraisal; of the 53 tested lamps: 18 lamps (around 34%) had very low temporal modulation (of less than 1%); 12 lamps (around 23%) had temporal modulation between 1% and 15%, similar to that of halogen and compact fluorescent lamps; 14 lamps (around 26%) had modulation between 12% and 70%; their values were significantly higher than those of halogen and compact fluorescent technologies; nine lamps (around 17%) had very high modulation, exceeding 70% and even reaching 100%. It is estimated that around 43% of LED lamps for domestic use have degraded temporal modulation performance (modulation rate greater than 15% at 100 Hz) compared to halogen and compact fluorescent technologies. The stroboscopic effect is particularly visible with LED lamps and luminaires having high temporal modulation at 100 Hz. Some LED lamps and luminaires have high enough modulation levels that the phantom array effect is perceptible, especially when driving a car. 3.3.5.3 Health risk assessment For people with epilepsy, based on the available data, it is not possible to quantify the risk of attacks being triggered in relation to the temporal modulation of an LED lighting system. Moreover, the experts consider that due to the limited number of exposure data, the risk associated with effects (headaches, migraines, visual fatigue) occurring in the frequency range (80-120 Hz) associated with LED exposure is not known. Page 15 / 24 ANSES Opinion Request No 2014-SA-0253 Based on the scientific data, it is not possible to conclude as to whether or not the perception of the stroboscopic or phantom array effect has an impact on accidents occurring when handling machines or tools, or on traffic accidents. 3.3.5.4 Susceptible population groups Studies dealing with the maturation of the visual contrast perception system in humans indicate that maximum temporal contrast sensitivity is reached during adolescence and young adulthood. These are therefore population groups particularly sensitive to modulated light. Epidemiological studies showing an association between modulated light and the triggering of migraine refer to migraine patients as a population group sensitive to modulated light. Work undertaken using older-generation fluorescent tubes showed that certain individuals had heightened sensitivity to temporal light modulations at the frequency of 100 Hz. In addition, studies have shown that some individuals visually perceive flicker at 100 Hz. Thus, with regard to certain health effects related to temporal light modulation, several susceptible population groups were identified: regarding headaches, migraine and visual fatigue: - children, adolescents and young adults; - migraine sufferers; regarding the risk of accidents related to the stroboscopic effect or phantom array effect: - machine and tool operators and vehicle drivers; - people with motor or cognitive disorders reducing their avoidance or decision-making capacities; - children, adolescents and young adults; regarding the triggering of epilepsy attacks: people with epilepsy. 3.4 Effectiveness of protective devices There are various solutions claiming to reduce or suppress the effects of blue light: these include filters built into computer screens or into the lenses of prescription glasses, as well as programmable lighting systems that modulate the quantity of melanopic light (wavelength of around 480-490 nm) depending on the time of day. According to the measurements taken for this expert appraisal: specific blue-light-blocking glasses were more effective at filtering than treated ophthalmic lenses. However, neither of these two systems was effective enough to be considered as personal protective equipment21 (PPE) regarding the risk of acute retinal phototoxicity resulting from prolonged exposure to a very high-intensity LED source; depending on the tested protective device, the capacity to filter blue radiation in the melanopic band was highly variable: it was very low or even non-existent for treated lenses, despite the claims made by manufacturers and distributors of these products. It cannot be said that this filtration is sufficient to prevent the decrease in melatonin secretion induced by exposure to light in the evening and the related effects of sleep onset delay; for the tested screens claiming to limit blue-light emissions, no real effectiveness was observed. However, reducing the colour temperature (switching to warm white) and brightness of the screens was somewhat effective at reducing the quantity of blue light in the spectrum. 21 There are currently no standards specifying test methods and performance requirements for PPE with regard to blue light. Page 16 / 24 ANSES Opinion Request No 2014-SA-0253 3.5 Environmental impact of LEDs 3.5.1 Threat to biodiversity The diversity of the living world is reflected in the wide variety of metabolic, physiological and behavioural responses to light observed in fauna and flora. Thus, what might be an advantage for a given plant or animal species may prove to be a disadvantage for another. Changes in the (daily and annual) biological rhythms, orientation, geographical distribution and migration of species can thus be observed following exposure to artificial light. There can also be indirect effects (in the medium and long term) on these populations and their ecosystems. Research into the impact on the living world of the light emitted by LEDs at night still heavily relies on that dealing with artificial light in general. Moreover, it still involves a very limited num ber of species. Regardless of the studied ecosystem, the general long -term trend as observed in the scientific literature appears to be an increase in mortality and a decline in the diversity of the animal and plant species studied in environments lit at night, including by LED lighting systems. According to the scientific literature, the effects of light at night, especially from LED lighting, on fauna and flora and ecosystems are proven for all of the species studied. Overall, these effects correspond to those of night-time lighting. It is important to distinguish those that could be specifically related to the particular characteristics of LEDs (intensity, spectral composition). These effects are combined with other anthropogenic pressures (chemical pollution, geographical barriers, shrinking habitats, overexploitation, etc.). The continuous extension of human, industrial and leisure activities in addition to physical and chemical nuisances combined with the effects of climate change are all factors that certain animal and plant populations will probably be incapable of coping with, which will speed up the decline in biodiversity. However, data involving the combined action of these multiple disruptive factors are still extremely scarce. 3.5.2 Light pollution The collective expert appraisal report associated with this summary includes an assessment of the effects of LED deployment (outdoor display and lighting sources in particular) on light pollution. Various aspects have been considered, such as effects on the sky glow, nuisances for humans (intrusive light, light trespass, glare, circadian rhythms) and nuisances for ecosystems and biodiversity. According to the Working Group's experts, the change in lighting technologies due to LEDs could either increase or reduce light pollution, depending on the choices made for public and indoor lighting, architectural and landscape enhancement, etc. The categories of LED lighting systems that may be responsible for the greatest increases in light pollution are as follows: illuminated signs, billboards and advertising, as well as lighting for commercial, agricultural (including horticultural greenhouses), aquaculture and industrial zones. This also encompasses lighting for outdoor car parks in these zones. In these categories, the trend is towards an increase in the number and intensity of points of light. Replacing lamps for street lighting and indoor lamps with LEDs could contribute to reducing light pollution, by better targeting areas to be illuminated (and thus limiting diffusion) and modulating the quality (wavelength) and intensity of the light emitted, as enabled by LED technology, provided that the number of points of LED light is not increased compared to the number of replaced points of light. Despite the results highlighted above, it is difficult to assess the overall impact of the transition from current lighting systems to LEDs on light pollution. Page 17 / 24 ANSES Opinion Request No 2014-SA-0253 3.5.3 Impacts related to the life cycle of LED lamps and luminaires Several categories of environmental impacts are defined when analysing the life cycle of a product: energy consumption, the amount of hazardous waste produced, the amount of water used, the impact on global warming, toxic effects on human health, etc. The results of the life-cycle analyses (LCAs) undertaken for the analysed light sources show that LED lamps and luminaires have the lowest environmental impacts compared to other lighting technologies. This is due to the higher light efficiency of LED lighting compared to other sources. However, the content of the LCA studies dealing with lamps and luminaires varied, especially in terms of the analysed products and chosen methods (the functional unit, impact categories and life-cycle stages included). Despite major differences in the LCA methods, the analyses generally led to very similar results: the LED use phase was primarily (70% to 99%) responsible for the environmental impacts observed, due to the energy consumption of this technology. Manufacturing was responsible for most of the other impacts. The CES notes that one limitation of the LCAs was the lack of a methodology for assessing the impacts of light on human health and the environment (fauna and flora). Recommendations of the CES Based on the Working Group's conclusions and recommendations, the CES is issuing the following recommendations aiming to better protect human health (general population and workers) and the environment from effects related to exposure to LED systems. These recommendations are intended to limit harmful effects related to exposure to LEDs by developing information for the general population and in the workplace and by improving the normative and regulatory frameworks governing the use of LEDs. Lastly, the CES highlights the efforts to be made in terms of research. Recommendations for the public authorities to protect the population and the environment The CES recommends developing actions and information regarding: the need to limit exposure to blue-rich light (from LEDs and other technologies), by favouring the use of warm-coloured lighting (colour temperature below 3000 K) before going to bed and during the night, especially for certain population groups: children, adolescents and pregnant women (see lists by health effect in Section 3). In particular, the CES recommends not using blue-rich night-lights for infants and children and limiting the exposure of children and adolescents to blue-rich light sources (computer, tablet, mobile telephone screens, etc.) at night and before going to bed; the importance of enhancing the light contrast between daytime and night-time by increasing exposure to natural light during the day and limiting exposure to artificial light before bedtime and at night; the phototoxic effects of light associated with exposure to certain LED lighting devices (hand- held lamps, head torches, toys, vehicle lights, blue-light decorative string lights) available on the market, especially for the most susceptible population groups such as children; the widely varying effectiveness of the protective devices currently proposed with regard to the adverse health effects associated with exposure to LEDs. In order to protect against the harmful effects of light pollution on humans and their environment, the CES recommends: undertaking actions to limit intrusive light in homes and thus reduce the risk of circadian disruption; Page 18 / 24 ANSES Opinion Request No 2014-SA-0253 limiting the number of illuminated outdoor facilities, keeping the surface areas of illuminated zones to a minimum, improving control of their directivity and promoting their sound management; conducting, wherever lighting is necessary, a study of its impact on the local ecosystem in natural and suburban areas; creating protected spaces, without any artificial lighting. Recommendations for employers and occupational physicians to protect workers considering the phototoxic effects of blue light and the potential effects of temporal light modulation, the CES reiterates the obligation to limit the exposure of workers to these light sources and inform them of the related hazards; moreover, given the effects observed on foetal development in animals related to maternal exposure to light at night, the CES recommends limiting the exposure of pregnant women to light during the night. Recommendations regarding the regulatory and normative frameworks with the aim of protecting human health and the environment At national level: the CES recommends enforcing the regulations on the switching-off of interior lighting with exterior emission and the illumination of building façades (Ministerial Order22 of 25 January 2013 on the nocturnal lighting of non-residential buildings in order to limit light pollution and energy consumption) as well as those on the switching-off of advertising signs (Decree no. 2012-11823 on outdoor advertising and signs). At European level: regarding normative changes to be made, the CES recommends: revising the exposure limits for optical radiation proposed by ICNIRP, so as to make them sufficiently protective against phototoxic risks. They should take into account chronic exposure and consider other indicators, especially those relating to infra-clinical toxicity24; creating an effectiveness index and requiring its labelling on devices providing protection against blue light (accounting for the attenuation rate); developing a metrological standard, at European level, specifying conditions for measuring temporal modulation and calculating the related indices; regarding regulatory changes to be made, the CES recommends: 22 “The interior lighting of premises for professional use must be switched off one hour after these premises have been vacated. Building façade lighting must be switched off at 1 am at the latest. Store window lights and window display lights must be switched off at 1 am at the latest or one hour after these premises have been vacated, whichever occurs later”. 23 “Illuminated advertisements must be switched off at night, between 1 am and 6 am, except for airports and urban units with more than 800,000 inhabitants, for which the mayors shall set out the applicable rules. Illuminated signs shall comply with the same rules”. 24 For example, there can be cell death in the retina without this being visible when examining the back of the eye. Page 19 / 24 ANSES Opinion Request No 2014-SA-0253 requiring the labelling of the photobiological risk group (assessed according to Standard NF ISO 62471) for domestic lighting as well as for LED objects; restricting the sale of LED systems (lamps, luminaires, objects and especially toys) to the general public to those in risk group 1 or lower; harmonising the regulatory framework by amending the regulations specific to LED systems other than lamps and luminaires, in order to take into account the photobiological risk, in particular: o Directive 2009/48/EC on the safety of toys; o UNECE25 (United Nations Economic Commission for Europe) Regulations R112 and R113 on prescriptions for light sources from vehicles. limiting the luminance of vehicle lights (without necessarily reducing the overall flux and therefore the range of vision); taking into account, in the regulations, the specific characteristics of bare LED strips and matrices in devices sold to the general public (bare LED aggregates on the same base); establishing, at European level, limits for temporal light modulation, in order to limit the biological and health effects associated with the light emitted by LED lamps and luminaires; amending the current regulations in order to take into account the risks associated with temporal modulation, in particular: o Directive 2006/25/EC of the European Parliament on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (artificial optical radiation); o the UNECE regulations, requiring a minimum modulation frequency of around 2 kHz when the lamps (front lamps and rear lamps) of vehicles are used in pulse width modulation26 (PWM) mode. This recommendation will limit the visibility of the phantom array effect, which is a source of proven visual disturbances; introducing the option to automatically lower the colour temperature (switch to warm white) and brightness of mobile telephone and tablet screens before bedtime. Research recommendations While numerous data are available on the health effects of light, especially blue light, the scientific data are still incomplete with regard to the specific effects of LEDs depending on their geometry and spectral quality. Therefore, the CES insists on the need to improve the quantitative assessment of the impact of a general shift to LED technology on human health and the environment. The CES encourages the implementation and intensification of research into light-induced circadian rhythm disruption and the resulting effects on vigilance, sleep, mood, well-being, cognition and health. Two aspects for which there is still little documentation should particularly be taken into account in humans and diurnal animal models: the impact of the maternal light environment on foetal development; 25 The UNECE Sustainable Transport Division provides secretariat services to the World Forum for Harmonization of Vehicle Regulations. 26 PWM mode is a duty-cycle modulation. Light is modulated at a fixed frequency and the change in the duty cycle modifies the average light intensity. Page 20 / 24 ANSES Opinion Request No 2014-SA-0253 for children and adolescents, the impact of the light environment, depending on the period (day, night), on biological rhythm synchronisation and health, particularly considering higher light transmission due to a clearer lens and a more open pupil. Since potentially beneficial effects of a strong light contrast between daytime and night-time have been described in the scientific literature, it will be necessary to: confirm the effects of exposure to sufficient daytime light intensities on quality of life, sleep, well-being and health, especially for people with circadian rhythm disorders (elderly subjects, hospitalised patients, people with dementia, etc.); improve knowledge of the ability of exposure to blue light in the morning to correct circadian desynchronisation and assess the associated ocular risks; for night workers, study the relevance of favouring exposure to certain wavelengths depending on the time of day, to promote vigilance on the one hand and recovery on the other hand while minimising the negative side effects. The CES recommends improving the assessment of the risk of eye dryness and ocular diseases occurring in relation to exposure to light in the phototoxic range, especially in the long term. Special attention should be paid to certain susceptible population groups (children, adolescents, people with ocular diseases, aphakic individuals, etc.). The CES also recommends studying the factors that may be involved in the phototoxicity of light, such as the time of exposure, the possible associated temporal modulation, and risk factors related to ocular diseases. It would also be advisable to study to what extent phototoxicity results obtained in rodents can be extrapolated to humans. Since temporal light modulation appears to be a major flaw of certain LEDs and LED systems, the CES recommends improving knowledge of its visual, biological and health effects. In particular, it recommends conducting: studies to better identify inter-individual variations in sensitivity to temporal contrasts and better understand the prevalence and incidence of effects related to temporal light modulation in the general population; studies enabling the risk of accidents arising from exposure to a stroboscopic effect or phantom array effect to be quantified. The various health effects of LEDs mentioned above make it necessary to improve the assessment of exposure in populations. The CES recommends taking precise measurements of luminance distribution, spectral energy distributions and temporal modulation for a wide range of LED devices to which the population is exposed. The CES recommends better taking account of the environmental impact of a general shift to LED technology, by improving knowledge regarding the effects of light pollution on fauna and flora and the ecosystem as a whole. Lastly, the CES recommends considering the entire life cycle of LEDs, in particular: accessing detailed data on the products used in the manufacture of LEDs (raw materials, manufacturing processes) and those released into the air, water and soil during the manufacture of LEDs; documenting end-of-life for LEDs: recovery and sorting of used products, recovery of raw materials, recycling of certain LED components, treatment of final waste. Page 21 / 24 ANSES Opinion Request No 2014-SA-0253 4. AGENCY CONCLUSIONS AND RECOMMENDATIONS ANSES endorses the conclusions and recommendations of its Expert Committee on “Physical agents, new technologies and development areas”, set out in Section 3 of this Opinion. An initial expert appraisal on the health effects of exposure to LED lamps was published by ANSES in 2010, when this technology was just starting to be deployed on a large scale and other lighting technologies (incandescent in particular) were beginning to be gradually withdrawn from the market at the same time. This expert appraisal had underlined the retinal toxicity of the blue light contained in LED lighting systems and their high capacity for glare. Long contained mainly in specific applications (signage, electronic objects, etc.), LED technology is increasingly being used in automotive vehicles (lamps, etc.) and has become essential in domest ic and public lighting as well as in light objects and screens (telephones, computers, televisions). The artificial light to which the population and its environment are exposed, which was previously rich in yellow-orange shades, is now richer in blue light than it was 10 years ago due to the now predominant use of LEDs in industrial and consumer applications. This expert appraisal sought to update the state of knowledge since 2010 on the various health effects likely to be associated with exposure to blue-rich light as well as other characteristics of LED lighting. To do so, it used a methodology for assessing the levels of evidence associated with the health effects in question. Moreover, due to the lack of literature data dealing with the population's exposure to LED technologies, the Agency financed specific measurement campaigns, in particular to describe the type and quantity of light emitted by LED systems used on a daily basis (lamps, objects featuring LEDs, vehicle headlamps, computer, tablet and mobile telephone screens, etc.). The new scientific data examined corroborated the findings of 2010 relating to phototoxicity and enabled the experts to establish that the retinal phototoxicity of acute exposure to blue-rich light is proven. The long-term contribution of blue-rich light to the occurrence of age-related macular degeneration (ARMD) is also proven. The Agency confirms that some of the tested lighting devices (hand-held lamps, vehicle lamps, LED spotlights, LED matrices, etc.) can produce high levels of glare. In 2010, the Agency had suggested the possibility of biological clock disruption induced by exposure to LEDs. The update of the expert appraisal showed that the disruption of circadian rhythms (biological clocks) induced by exposure to blue-rich LED light in the evening or at night is proven. Children and adolescents, exposed from a very early age to screens in particular (tablets, game consoles, mobile telephones, etc.), constitute a particularly susceptible population group. Regarding the temporal modulation of the light emitted by LEDs, the data examined showed that a high proportion of the tested LED lamps had degraded performance (high temporal modulation). Although the health risks associated with exposure to this modulation have not been determined, some people (children, adolescents, young adults, machine operators and vehicle drivers, etc.) may be more susceptible to the potential health effects of this light modulation: headaches, visual fatigue, risk of accidents, etc. Regarding the impacts of light on the environment and biodiversity in particular, the available studies show an increase in mortality and a decline in the diversity of the animal and plant species studied in environments lit at night, including by LED lighting systems. Page 22 / 24 ANSES Opinion Request No 2014-SA-0253 The Agency's recommendations Advance knowledge Regarding the assessment of risks related to exposure to LEDs, ANSES underlines the need to better quantify the risk levels associated with the identified effects. It thus recommends initiating additional research aiming to: improve knowledge of exposure for the general population, workers and the environment; better characterise the health effects associated with the temporal modulation of the light from LEDs in addition to long-term phototoxicity; clarify the exposure-response relationship between exposure and the occurrence of health effects (especially those involving circadian disruption, phototoxicity, etc.). Lastly, to respond to the potential health effects associated with exposure to LED phototherapy devices, the Agency advises the public authorities to have a risk-benefit assessment of these devices undertaken by a competent organisation. Adapt the regulations and improve information In light of the newly available experimental data concerning phototoxicity mechanisms, ANSES underlines the need to update the exposure limits (ELs) for blue light, especially to take into account the specific situation of children, whose eye lens filters blue light much less efficiently than that of adults and elderly people. These ELs are used to verify the compliance of LED systems with the essential health and safety requirements set out in European directives. Considering the results of the risk assessment undertaken as part of the collective expert appraisal, ANSES recommends adapting the regulatory framework applicable to LED systems, in order to: restrict the sale of LED objects to the general public to those in photobiological risk group 0 or 1; limit the light intensity of vehicle lamps, while guaranteeing road safety; establish, at European level, limits minimising the temporal modulation of the light emitted by all light sources (lighting systems, screens, LED objects), all while improving the characterisation of the related health effects. Pending changes to the regulations, ANSES recommends raising awareness in the population and encouraging people, children in particular, to limit their exposure to: blue-rich light before bedtime and during the night (LED screens: mobile telephones, tablets, computers, etc.); blue-rich lighting, i.e. “cool white” lamps and luminaires, by favouring indirect lighting or using diffusers; direct light from LED objects in risk group 2 or higher (hand-held lamps, toys, vehicle lamps, etc.). ANSES also draws attention to the varying levels of effectiveness of the current devices providing protection against the phototoxicity of blue light (treated lenses, protective glasses, specific screens, etc.). It also notes their lack of significant action on the preservation of circadian rhythm s for which, in the case of LED screens, exposure can only be limited by reducing the brightness and colour temperature of screens. It encourages the establishment of standards defining performance criteria for personal protective equipment in relation to blue light. Regarding the environment and biodiversity, although it is difficult to assess the overall health and Page 23 / 24 ANSES Opinion Request No 2014-SA-0253 environmental impacts of the transition from current lighting technologies to LEDs, ANSES recommends strengthening the prevention of light pollution. The Agency thus underlines the need to enforce the current regulations and adapt them, in particular by limiting the number of points of light and reducing light pollution, all while taking care to ensure the safety of people. Dr Roger Genet Page 24 / 24 ANSES Opinion Request No 2014-SA-0253 KEYWORDS Lumière bleue, LED, éclairage artificiel, phototoxicité, rythmes circadiens, modulation temporelle de la lumière, biodiversité, pollution lumineuse. Blue light, LED, artificial lighting, phototoxicity, circadian rhythms, temporal light modulation, biodiversity, light pollution. ANNEX Table 1: Main physical quantities used in the area of lighting Quantity Unit Description Luminance (L) Candela per square metre (cd/m²) Amount of visible light emitted by a light surface or an object, for example the luminance of a computer screen: around 200 cd/m² Illuminance (E) Lux (lx) Amount of light received on a surface. For example: 500 lux on a desk Colour temperature (T) Kelvin (K) Specifies the shade of a white light: a “warm” light will have a low temperature (yellowish colour, T < 3000 K), while a “cool” light will have a high temperature (bluish colour, T > 5000 K) Colour rendering index (CRI) No unit Ability of a light to faithfully render the colour of objects. A highly faithful light will have a CRI of 100, while a moderate- quality light will have a CRI below 80 Luminous efficacy Lumens per watt (lm/W) Defines the energy efficiency of a light source International Dark-Sky Association State Of The Science briefing: Artificial Light At Night (ALAN) 2020 John C. Barentine, Ph.D. IDA Director of Public Policy January 2020 Environmental pollution caused by artificial light at night (ALAN), commonly known as “light pollution,” is both a source of significant known and suspected hazards and growing exponentially in terms of its geographic presence and reach. This IDA State Of The Science briefing summarizes the evidence and impact of light pollution over a series of broad categories. Research results increasingly identify human over-consumption of ALAN as the fundamental driver of light pollution,1 and identify the main challenge as how best to maximize the benefits of outdoor light at night while simultaneously limiting its costs in both environmental and financial terms.2 The Night Sky Perhaps the most immediate manifestation of light pollution -- and the one that garners the most public attention -- is the phenomenon of skyglow. Skyglow forms over cities and other places with large installations of outdoor lighting, and results from the scattering of light emitted on the ground. While some of that light escapes the Earth’s atmosphere and can be sensed remotely by Earth-orbiting satellites, some fraction encounters molecules and/or small particles in the atmosphere and its path is redirected to the surface. Skyglow is characterized by an increase in the intensity of light in the night sky that diminishes the contrast between astronomical objects and the sky, making it more difficult to see those objects. Remote sensing of “night lights”, indications of ALAN, gives us our best view of the global scale of the problem of light pollution. Figure 1 shows a global composite map of night lights as observed in 2016 by the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard the NASA-NOAA Suomi National Polar-orbiting Partnership (NPP) satellite. The VIIRS Day- Night Band (DNB) yields images of the night side of the Earth with sufficient sensitivity to make meaningful quantitative measurements of night lights on spatial scales of less than one square kilometer per pixel. Together with earlier data provided by the U.S. Defense Department Defense Meteorological Satellite Program (DMSP), orbital measurements of light pollution dating to the 1970s are available for scientific study. Figure 1. Annual cloud-free composite view of night lights in Suomi NPP VIIRS-DNB. NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from M. Román (NASA's Goddard Space Flight Center). Researchers have learned much about the spread of light pollution across the globe. Of the world population, more than 80% of all people and more than 99% of the U.S. and European populations live in places where the night sky is fouled by light pollution.3 The extent to which the indication of ALAN appears in remote sensing data and the quantity of emitted light have increased by roughly two percent per year in recent years (Figure 2).4 The spatial variance of ALAN is large,5 and both indications and quantities of light are stable or decreasing in only a handful of countries.6 However, the VIIRS-DNB is completely insensitive to some of the light emissions of newer lighting technologies, meaning that figures reported in recent scientific studies are actually underestimates and should be taken only as lower limits. Ice and snow intensify skyglow due to their high reflectivity, enhancing upward-directed emissions from cities; models of Figure 2. Absolute change in the artificially lit area of the Earth during 2012-2016 as determined by remote sensing observations. Each pixel has a near-equal area of ~6,000 km2. Although the upper range of pixel colors cuts off at 200 km2, some pixels had changes of up to ±2,000 km2. Figure 2 from Kyba et al. (2017). skyglow formation over cities show an almost linear relationship between ground reflectance and artificial sky brightness.7 Measurements of the effect show an up to three-fold increase in night sky brightness in cities due to snow cover on the ground,8 and snow cover further amplifies skyglow itself due to reflections of the sky from the ground.9,10 Skyglow is also sensitive to the presence of very fine particles in the air, which may be increased by certain kinds of air pollution.11 Cloudy nights make the problem much worse; overcast conditions over cities are found to increase the intensity of light at the ground by a factor of up to ten.12 On the other hand, the comparative absence of ALAN in rural places means that cloud cover tends to darken the nighttime sky and landscape.13 The rapid rise in global light pollution is fueled by the increasing preference and commercial supply of solid-state lighting, a market dominated by white light-emitting diode (LED) technology. A consequence of this is a fundamental shift in the color characteristics of ALAN emitted into the nighttime environment.14 White LED lighting generally emits significantly more short-wavelength (i.e., blue) light than other lighting technologies, which can yield several times more contribution to skyglow.15,16,17 At the same time, the 2010’s saw the rapid rise of interest in places where natural nighttime darkness remains, fueling the growth of a new sustainable tourism model.18,19,20 Revenues from ‘astrotourism’ are estimated to be significant on regional scales,21 and this may encourage lighting practices and public policies that protect dark night skies. But it has also called into question the notion of what a “dark sky” is,22 and how natural darkness can or should be quantified in order to best preserve it.23 Wildlife ALAN exposure is known to harm a vast array of species on Earth. Organisms at or near the surface of the Earth experience natural illumination levels spanning nine orders of magnitude (Figure 3) with the timing and duration of those exposures largely determined by the Sun and Moon. Some species rely on dim sources of natural light, such as starlight, for orientation and navigation.24 ALAN is therefore a novel challenge to biological processes and Figure 3. Natural illumination during the day, sunset, and at night. Horizontal illuminance is shown on the y-axis, while the x-axis shows the altitude above the horizon for the Sun and Moon. SS = sunset, CT = civil twilight, NT = nautical twilight, AT = astronomical twilight. Adapted from Beier, P. (2006). Effects of artificial night lighting on terrestrial mammals. Pages 19–42 in C. Rich and T. Longcore, eds. (2005). Ecological consequences of artificial night lighting. Island Press, Washington, D.C. characteristics that evolved over billions of years in the presence of only natural sources of light at night. Over 160 species have been shown to respond to ALAN,25 and nearly all react in ways that negatively impact both individuals and entire Observed impacts are reported among birds,26,27,28,29 fishes,30,31,32 mammals,33,34,35 reptiles,36,37,38 amphibians,39,40,41 invertebrates,42,43,44,45,46 and plants.47,48,49 ALAN is known to disrupt physiological processes that rely on the daily and seasonal rhythms of light cues, such as foraging behaviors,50,51,52,53 timing of emergence54,55,56,57 and reproduction,58,59,60,61 and communication.62,63,64 ALAN exposure is further observed to reduce the cellular immune response of some organisms.65 ALAN interacts with organisms both endogenously (through their own biology) and exogenously (through their interaction with the environment). Endogenous harm from ALAN exposure generally results from the disruption of chemical signaling in the organism66 tied to the so-called circadian rhythm, a roughly 24-hour cycle of activity tied to the length of an Earth day. Exposure to sunlight, followed by many hours of darkness, establishes an environmental cue that helps ‘entrain’ the rhythm to the changing day length throughout the year at temperate latitudes. In addition, the visual systems of some species show sensitivity to the polarization state of light,67,68 suggesting that characteristics other than intensity, spectrum, duration and timing of ALAN exposure are important ecological considerations.69 Exogenous impacts of ALAN to wildlife typically involve modifying the nature of predator-prey interactions,70,71,72,73 diminishing the resiliency of food webs74 and threatening fitness of prey species (Figure 4). Affected species often also perform various ecosystem services that are subsequently affected (Figure 5).75,76,77 In many cases, dependencies exist between these species and the production of food crops. Other ways in which ALAN causes exogenous harms to species are by reducing options for foraging,78,79,80,81 altering reproductive strategies and/or output,82,83,84,85,86,87,88 affecting locomotion and orientation ability89 and creating or disguising barriers to safe mobility.90,91 It can also create conditions of phototaxis, the bodily movement of a motile organism in response to light. Phototaxis is a cause of injury and mortality in both bird and insect species.92,93,94 These results Figure 4. Fitness of prey species in the wild could be decreased with exposure to ALAN. Figure 1 from Russart, K., & Nelson, R. (2018). Artificial light at night alters behavior in laboratory and wild animals. Journal of Experimental Zoology A: Ecological and Integrative Physiology, 329(8-9), 401–408. doi:10.1002/jez.2173 indicate that ALAN is rapidly emerging as one of the most pressing and imminent threats to global biodiversity,95 and may be a direct contributor to observed population declines, especially among invertebrates.96,97 Figure 5. A schematic representation of the routes by which ALAN influences interspecific interactions, and the ecological consequences of those interactions. Figure 7 from Gaston, K., et al. (2014). Human alteration of natural light cycles: causes and ecological consequences. Oecologia, 176(4), 917–931. doi:10.1007/s00442-014-3088-2. Human Health The causal relationship between ALAN exposure and human health and wellbeing is a controversial subject far from clear definition. Despite the unsettled nature of the science, there are clear indications that ALAN has some effects on humans. These effects appear to stem largely from the ability of short-wavelength light to disrupt the circadian rhythm98,99 that governs everything from the timing of hormone secretion to the sleep-wake cycle (Figure 6). Exposure to ALAN at inappropriate times during this cycle delays or suppresses altogether the onset of the secretion of melatonin,100 a potent antioxidant known to interact with the immune system.101 Melatonin is suppressed at very low light intensities, as little as 6 lux in Figure 6. A flow-chart representation of the interaction of blue light in the external environment with the human visual and circadian systems. (Adapted from Kumar et al. 2019) sensitive humans,102 although a large range in human sensitivity to this effect is observed.103 The long-term health impacts of low-level ALAN exposure are unknown, but it is suspected that chronic exposure to dim ALAN has cumulative effects comparable to those from higher illuminances.104 The light-melatonin association is mediated by intrinsically photosensitive retinal ganglion cells (ipRGCs), a previously undiscovered type of light receptor in the human retina.105 ipRGCs contain a photopigment called melanopsin, whose sensitivity to blue light is exceptionally strong.106 Signals from ipRGCs exposed to blue light are directed to the master circadian ‘clock’ in the hypothalamic suprachiasmatic nucleus (SCN) of the brain, establishing a timing reference for other ‘clocks’ in other organs and systems in the body that regulate a variety of biological activities, including energy homeostasis.107 Exposure to ALAN causes internal desynchrony associated with resetting of the circadian clock.108 Further, it is now recognized that ALAN exposure results in epigenetic changes to individuals,109,110 resulting in modification of core clock genes known to result in some routes of carcinogenesis.111,112,113 Sufficient evidence exists suggesting a link between ALAN exposure and both acute and chronic health effects, but great caution is needed to properly interpret research results. A robust conclusion about human exposure to ALAN is that it is an emergent ‘lifestyle risk’ associated with metabolic disorders and related morbidities, including obesity,114,115 diabetes,116,117 and certain types of cancer.118,119 ALAN exposure is similarly associated with the promotion of metastases of some cancers,120 resistance to drug therapies,121 and an increase in systemic oxidative stress.122 Other known chronobiological effects include both acute and chronic insomnia,123,124 with implications for public health and worker safety and productivity. Practitioners are slowly recognizing the importance of the role played by ALAN in healing and restoration of health, with effects noted for conditions as varied as cerebral ischemia,125 atherosclerosis,126 dermal wounds127 and systemic inflammation.128 Health outcomes, especially for patients in hospital settings, are increasingly connected to controlling ALAN exposure.129,130 Other studies identify ALAN as an influence on the progress of normal aging.131,132 There are also indications of ties between ALAN exposure, chronic circadian disruption and mental illness, mediated by the same factors that appear to cause organic disorders.133,134,135,136 And limited evidence exists suggesting that ALAN exposure may cause developmental defects in humans.137,138 On the other hand, limiting ALAN exposure -- especially short-wavelength ALAN - - helps maintain normal circadian rhythmicity and ameliorate metabolic abnormalities.139 We understand much about the underpinnings of ALAN interaction with mammalian biological systems, independent of the source of the ALAN photons. Still, it is not possible at this point in time to draw a direct connection between ALAN exposure in outdoor settings and the incidence of disease in individuals or populations. Public Safety Among the causes of light pollution is the popular belief that the use of outdoor light at night necessarily improves road and traffic safety and discourages or prevents the perpetration of both violent and property crimes. While under certain circumstances the careful application of outdoor lighting may improve nighttime safety, this belief is not grounded in peer-reviewed scientific evidence. As concerns the impact of outdoor lighting on both crime and road safety, a survey of the literature reveals conflicting results. Some studies find evidence for a positive correlation in which crime or road collisions decrease after application of lighting treatments,140,141 while others find either a negative correlation,142 none at all,143,144,145 or ambiguous results.146 A few authors turn the question around and ask whether reducing outdoor lighting in areas prone to either crime or road collisions leads to poorer outcomes, finding little or no such evidence.147 Among the practical barriers to a clear determination of the effect of outdoor lighting on public safety is an inability to model whatever underlying mechanism may exist. Jackett and Frith (2013) rightly note that “no well-established dose-response relationship to lighting parameters exists from which one can deduce benchmark levels of lighting for safety.”148 One consequence, as Fotios and Gibbons (2018) write, is that “recommendations for the amount of light [for drivers and pedestrians] do not appear to be well-founded in robust empirical evidence, or at least do not tend to reveal the nature of any evidence.”149 A significant limiting factor in drawing clear and unqualified conclusions about the interaction of outdoor lighting and crime and road safety is that carefully controlled studies involving both are notoriously difficult to design, conduct, and interpret. As a result, many of the claims about outdoor lighting and its impact on public safety -- for better or worse -- may be fundamentally wrong.150,151 A separate issue regarding road traffic is whether automotive lighting itself is a source of objectionable light pollution, specifically in relation to its utility as a means of ensuring public safety. There is little research to date on the overall contribution of automobile lights to light pollution, although early work suggests that the impact is non-trivial.152,153,154 Also, researchers are only beginning to contemplate the implications for the need for future installations of roadway lighting as the result of the introduction of autonomous (self-driving) vehicles.155 Energy Security Wasted outdoor light at night is wasted energy. To the extent that humans remain strongly dependent on carbon fuels to generate electricity, the issue of light pollution is one of energy use and its influence on global climate change. Prior to the introduction of energy-efficient solid- state lighting (SSL), electricity used to power outdoor lighting accounted for about 1.5% of global power consumption.156 Motivated by the potential cost-of-ownership savings through reduced energy consumption and “green” policies promoting sustainable practices, municipalities have rushed to convert public outdoor lighting systems from incumbent technologies such as high-intensity discharge lighting to SSL. As prices of SSL lighting products steadily declined through the 2010’s and the capital payback time for new installations decreased, the adoption rate of the new technology accelerated. This seems at first glance to be beneficial to the environment; the United Nations Environment Program estimates that a transition to energy efficient lighting would reduce global electricity demand for lighting by 30-40% in 2030.157 However, the exceptionally rapid global transition to SSL in the name of energy efficiency may inadvertently worsen the problem of light pollution by making outdoor light at night cheaper to produce, fueling higher consumption. As ALAN has become cheaper to produce, its consumption has increased substantially; humans now consume thousands of times more lumens than they did in the past.158 In fact, there are signs of an emerging economic rebound effect in which the efficiency gains brought about by the adoption of SSL are eroding expected savings in both energy consumption and related carbon emission. The median global increases in gross domestic product (GDP) by country since 2010 approximately match the median country’s increase in the use of ALAN, and are “inconsistent with the hypothesis of large reductions in global energy consumption for outdoor lighting because of the introduction of solid-state lighting.”159 Therefore, claims concerning the purported environmental benefits of LED lighting may be, at best, overstated. It has been argued that this calls for a new definition of ‘efficiency’ that considers primarily the total cost of light rather than simply its electricity cost.160 Absent regulation of outdoor light use to curb consumption, SSL threatens the same negative externalities that accompanied earlier technologies in terms of light pollution. When these externalities are considered as part of the total cost of SSL retrofits, their apparent benefits to society appear to fade. For example, one study of a municipal SSL retrofit effort in the United States found a ten-year rate of return of -146.2% compared to +118.2% when the costs associated with avoided carbon emissions and health outcomes related to ALAN exposure are ignored.161 When these externalities are included in return on investment calculations, energy efficiency programs appear no more or less attractive than indications from conventional estimates that include only energy savings. The jury thus remains out on the question of whether SSL can deliver its promised environmental benefits, taking into account the costs of unintended consequences, without a concomitant reduction in total global consumption of outdoor ALAN. References 1 Leng, W., He, G., & Jiang, W. (2019). Investigating the Spatiotemporal Variability and Driving Factors of Artificial Lighting in the Beijing-Tianjin-Hebei Region Using Remote Sensing Imagery and Socioeconomic Data. 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Seven centuries of energy services: The price and use of light in the United Kingdom (1300-2000). Energy Journal, 27, 139–177. No doi. https://www.jstor.org/stable/23296980. 159 Kyba et al. 2017. 160 Kyba, C., Hänel, A., & Hölker, F. (2014). Redefining efficiency for outdoor lighting. Energy and Environmental Science, 7(6), 1806–1809. doi:10.1039/c4ee00566j. 161 Jones, B. (2018). Spillover health effects of energy efficiency investments: Quasi-experimental evidence from the Los Angeles LED streetlight program. Journal of Environmental Economics and Management, 88, 283-299. doi:10.1016/j.jeem.2018.01.002. May 28, 2020 Cancer Risk Increase from Blue Wavelength Light Studies have shown that the risk of cancer, especially breast and prostate cancers, is greatly increased by exposure to blue wavelength light at night. The following research studies investigate the issue of cancer increase from blue wavelength light. Quote: “Artificial light at night is significantly correlated for all forms of cancer as well as lung, breast, colorectal, and prostate cancers individually. Immediate measures should be taken to limit artificial light at night in the main cities around the world and also inside houses.” Evaluating the Association between Artificial Light-at-Night Exposure and Breast and Prostate Cancer Risk in Spain (MCC-Spain Study) https://ehp.niehs.nih.gov/doi/10.1289/ehp1837 Outdoor Light at Night and Breast Cancer Incidence in the Nurses’ Health Study II https://ehp.niehs.nih.gov/doi/10.1289/ehp935 Artificial Light at Night and Cancer: Global Study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5454613/ Additional articles on the topic. Evidence Supports Link Between Breast Cancer, Light Exposure at Nigh t https://today.uconn.edu/2017/08/evidence-supports-link-breast-cancer-light-exposure-night/ Blue light’s link to prostate and breast cancers https://www.aoa.org/news/clinical-eye-care/blue-lights-link-to-prostate-and-breast-cancers Dear City Council, The level of awareness of the dangerous of high color temperature, undiffused LED light has increased significantly in the past few years as LED lights have inundated our world. Legally, once a government entity has a reasonable suspicion about a danger, the government is obligated to investigate and take corrective action. Law firms across the country are now seizing on the information about the dangers of high energy, blue wavelength light and assessing the informat ion for litigation. Below is an image from an LED street light conversion on Burnt Store Road in Florida. This unconscionable lighting was installed directly over burrowing owl habitat. The 5000K LED lights with no shielding are damaging people's eyes and destroying the ecosystem. In contrast, below is a photo from a recent conversion in the city of Seattle. This is a 2700K LED street light that is shielded and diffused. Notice how there is very little glare, but plenty of illumination. Unshielded, 3000K/4000K/5000K LED lights are harsh, cause eye damage and psychological anguish, and lead to increases in cancer and diabetes. 3000K/4000K/5000K LED lights are inappropriate and dangerous. The American Medical Association studied this carefully and released their report in 2016 setting a maximum color temperature of 3000K. Since the release of that report, numerous additional studies have shown that blue wavelength light is dangerous for human eyes, human health and especially the health of our wildlife and ecosystem. The AMA now recommends using as a low a color temperature as possible. 2200K is a typical safe value. A recent successful lawsuit by the Hawaii Wildlife Fund illustrates the seriousness of the issue. https://earthjustice.org/news/press/2020/maui-county-illegally- circumvented-environmental-review-for-led-streetlights-project Here is an article about a human-safe, turtle-safe lighting project in Gulf Shores, Alabama: https://www.ledsmagazine.com/lighting-health- wellbeing/article/14175583/sea-turtles-thrive-with-amber-led-lighting-and-dark-sky- advocates-rejoice Another concern is for those with light sensitivity disabilities such as autism, highly sensitive persons, migraine sufferers, lupus, PTSD, and photophobia. This class of persons is protected by the Americans with Disabilities Act and high color temperature lights can cause significant harm to them. Any lighting changes by the city must accommodate the needs of the light sensitive disabled. 2700K or less color temperature, non-strobing, non-flickering lights are most likely to be safe for this group. We would like to take this opportunity to inform you about the issue of LED lights and light pollution. Here is a sample photo of a high glare LED light shining directly into our eyes that steals our vision, causes us pain, wastes energy, and makes us feel unsafe. A single LED light can save energy, but there is also a significant downside to using LED. We would like to provide information to help your council make wise outdoor lighting decisions. Light pollution is increasing across the world at an unsustainable rate of 2% per year. This is having a devastating effect on our ecosystem, wildlife, and human health. We need to be taking strong measures to reduce how much light we are introducing into our nighttime environment. LED lights have a large spike of blue wavelength light. As you can see in the chart below, the first step to making LED lights human safe is to use a color temperature of 2700K or less. Many studies have already shown the dangers of blue light at night, including increased risk of cancer. This is now well-known science. Here are two examples: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3002207/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4734149/ Here is a database containing hundreds of abstracts of research articles about the dangers of LED lights. http://alandb.darksky.org/ The graphic below can be used to help understand what color temperatures are safe. Essentially, anything to the left of G-Index 1.56 (+/- .15) starts to become uncomfortable and painful due to too much blue and too much glare. Anything to the right of 1.56 (+/- .15) is comfortable for most people. For human health and ecosystem health, the farther right the better. We make the following recommendations: 1) The first task is for the council to set a city-wide light pollution maximum of Class 3 or better on the Bortle scale. This goal should take 5 years or maybe even 8 years but set a hard deadline. By setting the overall light pollution maximum into place, everything else about lighting will make a lot more sense to all your stakeholders. 2) Set 1700K as the standard color temperature for outdoor lights. 2200K is acceptable for residential neighborhoods. Possibly use 2700K in limited business districts, but never exceed this amount because that blue spike is uncomfortable and painful for too many people. Studies have shown that bright white LED lights make our environment less safe than low glare, low color temperature lights. 3) Use the lowest possible lumens for brightness. Human eyes are extremely sensitive. There will be no loss of safety by keeping the lights dim. 4) Ensure that all outdoor lights are shielded and diffused. Light should not be directly into our eyes or wasted up into the sky. Bare diode LEDs are too dangerous for human eyes. 5) Have your lighting vendor write into their contract that they are using high quality driver electronics that do not cause sub-sensory flicker. Using high quality drivers will also reduce failure rates and long-term costs. 6) Cars now have Automated Braking Systems and by 2022, all new cars will have this system. Using 1700K to 2700K streetlights will reduce glare which will help both humans and automated systems. Also, since cars are now safer driving themselves, it's time to start the process of removing tall street light poles altogether. We no longer need to light the roadway where cars travel. We only need a small amount of light for pedestrian walkways and bike paths. 7) Strobing LED lights such as on stop signs, police cars and utility trucks cause psychological torment and unsafe distractions. Research has shown that randomly strobing lights endanger first responders and the public. High intensity, high glare, randomly strobing LED lights should be banned. Here are two examples. Stop Sign: https://youtu.be/33ukzccm9qc Utility Truck: https://www.youtube.com/watch?v=ma0hGwHivO4 8) Ban non-essential LED billboards. LED Billboards are a significant safety distraction and cause of light pollution. Cities that allow LED billboards are liable for the accidents they cause. Thank you for taking time to read through this information and thank you for taking action to protect human health and the health of our ecosystem. May 31, 2020 The Impacts of Light on Crime By Soft Lights It is a common myth that brighter lights mean less crime and better safety. We say “myth” because the research does not prove the myth to be true. When people speak of “safety”, it is not even understood what this word refers to. Are we speaking of reducing the chance of personal attack from a human? Or an attack from an animal? Does bright light reduce the likelihood of a property crime? Does safety mean that we are less likely to trip over something? Does safety mean that we are less likely to be involved in a car crash? And what about our health? Is it “safe” for our eyes and our circadian rhythm cells to have bright lights shining at night? When we read the research studies, the general answer is that there is no definitive answer. It is certainly clear that bright lights do not equal more safety just as a rule. In fact, the studies might be showing the opposite to be true, that the general rule might be that brighter lights mean less safety. What we do know is that artificial light at night causes significant health problems to humans and to wildlife. Therefore, the strong negative effects of ALAN on health should be weighed against the minor positive or negative benefits of ALAN on crime or accidents. We were unable to find many original studies on this topic. If we become aware of additional studies, we will include them into this document at that time. Scientific Studies National Institutes of Health Quote: “We found no convincing evidence for associations between street lighting reductions and road traffic injuries.” https://www.ncbi.nlm.nih.gov/books/NBK316511/ (A review of a study in England and Wales) Quote: “While there was significant statistical heterogeneity in effects estimated at police force level, results overall were suggestive of an association between dimming and reductions in crime, particularly for violent crime.” https://jech.bmj.com/content/69/11/1118 (This is different review of the same England and Wales study) Additional Articles Quote: “Although four of these studies found desirable effects from improved lighting, the others did not; a review published by the U.S. Department of Justice of the seven studies undertaken in the 1970s concluded that improved lighting was not an effective means of preventing crime.” https://cops.usdoj.gov/RIC/Publications/cops-p156-pub.pdf Quote: “evidence is mounting that nighttime brightness may do little to stop crime, and in some cases may make it worse.” https://www.washingtonpost.com/news/wonk/wp/2017/11/02/what-actually-happens-to-crime-when- the-lights-are-on-as-rick-perry-suggests/ Quote: “It may make us feel safer, but has not been shown to make us safer” https://www.darksky.org/light-pollution/lighting-crime-and-safety/ Quote: “Spaces with warmer colour temperatures are perceived as safer places.” https://theconversation.com/more-lighting-alone-does-not-create-safer-cities-look-at-what-research- with-young-women-tells-us-113359 Untrustworthy Studies Urban Labs The Urban Labs study used 600,000 lumen lights, which equates to human torture. This study was performed in only one impoverished neighborhood, presumably because a rich neighborhood would never tolerate such torture. This study is only listed here to alert the read that this study must be dismissed as useless. https://urbanlabs.uchicago.edu/attachments/e95d751f7d91d0bcfeb209ddf6adcb4296868c12/store/cca 92342e666b1ffb1c15be63b484e9b9687b57249dce44ad55ea92b1ec0/lights_04242016.pdf Outdoor Lighting Design Guide The purpose of this document is to alert decision makers to important issues related to the installation of LED outdoor lights. These design criteria include color temperature, human health, flora and fauna, and people with light sensitivity disabilities. Color Temperature Probably the most important criteria for lighting is color temperature. The advent of outdoor LED lighting has created a technology that can be unsafe for humans and for wildlife. This is because the main driver of LED emits blue wavelength light, which research has shown is dangerous when the blue peak is too high. Here is a chart showing the spike of blue wavelength light in different color temperature LEDs. As you can see from the chart, the blue spike is far too large in comparison to the other wavelengths until about 2700K. In comparison, below is a chart for a typical incandescent light. Note how there is very little blue wavelength light, but a large amount of red wavelength light. When outdoor LEDs first came out several years ago, there were very few options. Cities that were early adopters chose what was available, which was 5000K. Ever since, residents have been complaining bitterly to their city councils about these high glare lights. As technology has been refined, cities have been moving from 5000K to 4000K to 3000K and now 2700K, 2200K and 1700K. The American Medical Association studied this carefully and released their seminal report in 2016. Their stated maximum for the time was 3000K. However, as new research has been released in the past 4 years, the AMA now recommends a maximum color temperature of “as low as possible.” The consensus now is that 2700K as the maximum safe, comfortable color temperature. This value matches the science, but it also matches personal feelings. Not all people react to high color temperature, but many do, especially those with light sensitivity disabilities. Therefore, the maximum color temperature for an outdoor lighting project should be 2700 Kelvin. Diffusion LEDs produce visible light that is spread over a wide part of the visible light spectrum. Because LEDs focus light on a small area, the result can be injury to the eye. Therefore, any product that you select should have advanced optics that incorporate diffusion properties or external diffusers such as frosted glass to scatter the light source. Shielding Shielding is an important criterion to keep the light focused where it should go. There should be no uplight. Also, lighting should not trespass onto private property. The Illuminating Engineering Society and the International Dark Sky Association just recently agreed to a strategic partnership to address the issue of light pollution. Below are the 5 Principles for Responsible Outdoor Lighting. Sub-sensory Flicker Some sensitive people can detect the switching between the DC LED and the A/C grid. This is known as sub-sensory flicker. This is typically caused by cheap driver electronics. Therefore, ensure that your vendor provides, in writing, a guarantee that there is no sub-sensory flicker. Brightness We tend to over light. As noted in the IES/IDA chart above, it is important to use the lowest lumens possible. Human eyes have cells for day vision and night vision. As we switch to night vision, our ability to see color is reduced, but our sensitivity increases. The high CRI of LED light will already improve our ability to see color, so it is important not to use a light that has too many lumens. Refer to IES Standard RP-8-18 for details, especially chapters 2 and 4. Color Rendering Index The CRI of HPS is typically less than 40. LED lights can utilize multiple blends of phosphor to achieve a specific CRI ranging from 65 to over 97 CRI. Therefore, any LED light utilizing this type of phosphor blend will have a vastly improved CRI versus HPS. LED lights can also use single color dies, such as narrow band amber or red, which can have a CRI below zero, which means color rendering that is worse than HPS. However, there are numerous health and ecosystem benefits to using narrow band amber or red which outweigh the benefits of a high CRI. Therefore, CRI should be given a low priority compared to other design parameters. Safety There will be some residents that will be concerned that if an area is not super bright, they will not be safe. Their feelings may be valid, but the truth is that they will not be any safer with super bright lights. There are numerous studies about the safety of bright lights, but the results are ambiguous. In other words, safety comes from factors other than bright white lighting. Studies have also shown that women, as a group, feel safer with a softer, warmer color temperature of 2200K or 2700K versus the harsh white color of a 4000K LED. Time of Day There is a considerable drop off in human activity later into the night. Therefore, if the design team plans on procuring devices that allow control of the brightness, then set up a system where the brightness can be controlled by time of night. For example, if a streetlight is normally operating at 500 lumens, perhaps 100 lumens would be sufficient after 11:00pm. In addition, consider using motion sensors to further reduce the light to zero when not in use. Bat Friendly Research has shown that bat feeding is greatly impacted by lighting at night. Outside of city centers, use approximately 1000K red LED lighting. Here is an example of bat-friendly lighting in Worcestershire, England. Their studies have shown that there is no reduction in safety when using this color temperature of light. Light Sensitivity Disabilities A significant percentage of the human population is very sensitive to light. They can perceive light that neurotypicals cannot or their emotions are triggered in ways that neurotypicals are not triggered. We know that color temperatures exceeding 2700K can cause emotions of anger, agitation, thoughts of suicide, fear, and depression in highly sensitive persons. Strobing LED lights can be even worse. The class of people with light sensitivity disabilities include those with autism, PTSD, epilepsy, bipolar disorder, highly sensitive persons, migraine sufferers, post-concussion sufferers, lupus, and others. The Americans with Disabilities Act protects this class of people. Therefore, the lighting design team must ensure that any lighting designs do not harm those with light sensitivities. In general, this means 2700K or less and no sub-sensory flicker. However, please check with your local disability rights group to ensure that all needs are met. References Safety https://theconversation.com/more-lighting-alone-does-not-create-safer-cities-look-at-what-research- with-young-women-tells-us-113359 https://jech.bmj.com/content/69/11/1118 https://www.ama-assn.org/sites/ama-assn.org/files/corp/media-browser/public/hod/a12-csaph- reports_0.pdf Bat Friendly https://www.bbc.com/news/uk-england-hereford-worcester-49534621 Mark Baker Soft Lights www.softlights.org mbaker@softlights.org From:Connie Cunningham To:City of Cupertino Planning Commission Subject:August 11, 2020 Planning Commission, Bird Safe Design/Dark Sky, Agenda Item 3 Date:Monday, August 10, 2020 7:45:36 PM CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe. Dear Chair and Planning Commissioners: August 11, 2020 Planning Commission, Bird Safe Design/Dark Sky, Agenda Item 3 Part 1. Bird Safe Design I call on you to join with many bird and human lovers to support the Staff recommendation for City-wide guidelines for Bird Safe Design. Birds live in our neighborhoods, sharing our trees and bushes as places to live. It is not far from one of our bushes to running into one of our windows. There are many ways to protect birds from smaller structures. Although it may seem that smaller structures are not as big a problem, it is the sheer number of smaller structures that make them a problem. It takes awareness of this problem to help people realize that they can help care for some of the smallest living creatures among us. Your support will go a long way to educating all residents of the role we play in the long term health of our environment and saving birds who bring us the thrill of flight, life and color in small packages. Part 2. Dark Sky I join with many bird lovers, and those who know that light pollution is affecting the health of humans, too, to urge you to support the Staff recommendation for Dark Sky lighting requirements. In the future, I hope that the City will look into strengthening its color temperature limit from 3,000 to 2,700 Kelvin. We recently visited Lassen National Park, and the difference in the night sky there with ours here is readily apparent. It would be sad, indeed, if the app called Sky View became the only way that people will see stars and the Milky Way Galaxy in the future. Please support Bird Safe Design and Dark Sky recommendations of the Staff!! Sincerely, Connie L. Cunningham Cupertino resident Member of Santa Clara Valley Audubon Society