Showing posts with label streetlights. Show all posts
Showing posts with label streetlights. Show all posts

Thursday, April 26, 2018

Are Your LEDs Killing You?

Light from energy saving LED’s may be giving us cancer
A study performed by an international team led by the Barcelona Institute for Global Health (ISGlobal), a centre supported by the “la Caixa” Foundation, reports a link between exposure to blue light at night and higher risk of developing breast and prostate cancer. Blue light is a range of the visible light spectrum emitted by most white LEDs and many tablet and phone screens. The results have been published in Environmental Health Perspectives.
“WHO’s International Agency for Research on Cancer (IARC) has classified night shift work as probably carcinogenic to humans. There is evidence pointing to an association between exposure to artificial light at night, disruption of the circadian rhythm, and breast and prostate cancers. With this study we sought to determine whether night exposure to light in cities can affect the development of these two types of cancer”, explains Manolis Kogevinas, ISGlobal researcher and coordinator of the study. “We know that depending on its intensity and wave length, artificial light, particularly in the blue spectrum, can decrease melatonin production and secretion”, says Martin Aubé, physics professor at CÉGEP in Sherbrooke, Canada and study co-author.
The study was conducted within the framework of the MCC-Spain project cofunded by the ‘Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública’ (CIBERESP), and includes medical and epidemiological data of more than 4,000 people between 20 and 85 years of age in 11 Spanish regions. Indoor exposure to artificial light was determined through personal questionnaires, while outdoor levels of artificial light were evaluated for Madrid and Barcelona, based on nocturnal images taken by astronauts aboard the International Space Station.
Aerial image of the city of Barcelona (Spain) taken by astronauts of the International Space Station.
many sections of the city use mercury vapor lamps (orangish) but note the sections that are blue-whitish.
CREDIT Image courtesy of the Earth Science and Remote Sensing Unit, NASA Johnson Space Center. http://eol.jsc.nasa.gov
Results obtained for both cities show that participants exposed to higher levels of blue light had a 1.5 and 2-fold higher risk of developing breast and prostate cancer, respectively, as compared to the less-exposed population.

Ariadna García, ISGlobal researcher and first author of the study, says: “Given the ubiquity of artificial light at night, determining whether it increases or not the risk of cancer is a public health issue”. At this point, further studies should include more individual data using for instance light sensors that allow measuring indoor light levels. It would also be important to do this kind of research in young people that extensively use blue light emitting screens”.
I'm not that concerned. I have a lot of doubts about their ability to gauge the outdoor exposure to LEDs from satellite photos like the one above.

We have been slowly converting many of the lights in our house to LEDs. The CFLs were a pain in the neck.

Saturday, July 2, 2016

Blue Light Special?

AMA issues warning about “Energy Efficient” LED Streetlights
The American Medical Association is concerned that the glare, the high blue light content of “energy efficient” LED streetlights being rolled out across America, might be suppressing drivers’ night vision, and causing other harmful health effects.
AMA Adopts Community Guidance to Reduce the Harmful Human and Environmental Effects of High Intensity Street Lighting
For immediate release:
June 14, 2016
CHICAGO – Strong arguments exist for overhauling the lighting systems on U.S. roadways with light emitting diodes (LED), but conversions to improper LED technology can have adverse consequences. In response, physicians at the Annual Meeting of the American Medical Association (AMA) today adopted guidance for communities on selecting among LED lighting options to minimize potential harmful human and environmental effects.
Converting conventional street light to energy efficient LED lighting leads to cost and energy savings, and a lower reliance on fossil-based fuels. Approximately 10 percent of existing U.S. street lighting has been converted to solid state LED technology, with efforts underway to accelerate this conversion.
“Despite the energy efficiency benefits, some LED lights are harmful when used as street lighting,” AMA Board Member Maya A. Babu, M.D., M.B.A. “The new AMA guidance encourages proper attention to optimal design and engineering features when converting to LED lighting that minimize detrimental health and environmental effects.”
High-intensity LED lighting designs emit a large amount of blue light that appears white to the naked eye and create worse nighttime glare than conventional lighting. Discomfort and disability from intense, blue-rich LED lighting can decrease visual acuity and safety, resulting in concerns and creating a road hazard.
In addition to its impact on drivers, blue-rich LED streetlights operate at a wavelength that most adversely suppresses melatonin during night. It is estimated that white LED lamps have five times greater impact on circadian sleep rhythms than conventional street lamps. Recent large surveys found that brighter residential nighttime lighting is associated with reduced sleep times, dissatisfaction with sleep quality, excessive sleepiness, impaired daytime functioning and obesity.
The detrimental effects of high-intensity LED lighting are not limited to humans. Excessive outdoor lighting disrupts many species that need a dark environment. For instance, poorly designed LED lighting disorients some bird, insect, turtle and fish species, and U.S. national parks have adopted optimal lighting designs and practices that minimize the effects of light pollution on the environment.
Recognizing the detrimental effects of poorly-designed, high-intensity LED lighting, the AMA encourages communities to minimize and control blue-rich environmental lighting by using the lowest emission of blue light possible to reduce glare. The AMA recommends an intensity threshold for optimal LED lighting that minimizes blue-rich light. The AMA also recommends all LED lighting should be properly shielded to minimize glare and detrimental human health and environmental effects, and consideration should be given to utilize the ability of LED lighting to be dimmed for off-peak time periods.
The guidance adopted today by grassroots physicians who comprise the AMA’s policy-making body strengthens the AMA’s policy stand against light pollution and public awareness of the adverse health and environmental effects of pervasive nighttime lighting.
The local community recently had a little to-do about street lights. In a cost cutting move, the county threatened to turn of the street lights on our two miles of private roads, and residents were split on what to do. Many wanted the community association to pay (which it can't afford), others were fine with no street lights. Our street, which was developed late, has no lights, and when I walk Skye for her late night pee walk, I enjoy the moon and stars, occasional meteors, and, in season (now) the fireflies.

One suggestion was LED streetlights to save money. In the meantime, after the hubbub the county cancelled it's plan for at least a year. In the meantime, I'll pass this on to my representative on the civic association board (Georgia), for her to take up with the board, or not, her choice.