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White LEDs induce retinal degeneration and contributes to the onset of early stages of age-related macular degeneration AMD (2017-01-10)

To save energy, the European directives from the Eco-design of Energy Using Products (2005/32/CE) have recommended the replacement of incandescent lamps by more economic devices such as Light Emitting Diodes (LEDs).

However, the emission spectrum of these devices is enriched in blue radiations, known to be potentially dangerous to the retina.
Recent studies showed that light exposure contributes to the onset of early stages of age-related macular degeneration (AMD).

Now researchers investigate, in albinos and pigmented rats, the effects of different exposure protocols.

Twenty-four hours exposure at high luminance was compared to a cyclic (dark/light) exposure at domestic levels for 1 week and 1 month, using different LEDs (Cold-white, blue and green), as well as fluorocompact bulbs and fluorescent tubes.

Behind the phototoxicity of LED bulbs, a culprit: blue light. "White light, whether natural or artificial, actually combines rays of different colors, each corresponding to a specific wavelength" explains Alicia Torriglia, who supervised this work with Professor Behar-Cohen.
Each light source - LEDs, fluorescent tubes or compact fluorescent bulbs - combines different colors in varying proportions and the potential toxicity of each of them on the retina depends both on the intensity of light and the wavelengths that compose it.

The rays corresponding to the blue light are more energetic than the others. They are also known to be more deleterious for equivalent exposure times and light intensities.
"Thanks to our observations, we have shown that the light emitted by LEDs produces two parallel toxic phenomena: apoptosis, but also a second form of cell death, necrosis, and necrosing causes a cell to damage its neighbors. This explains why the toxicity of blue light is higher than that of other wavelengths ".

The data suggest that the blue component of the white-LED may cause retinal toxicity at occupational domestic illuminance and not only in extreme experimental conditions, as previously reported.

It is important to note that the current regulations and standards have been established on the basis of acute light exposure and do not take into account the effects of repeated exposure.

THE FRENCH AGENCY FOR FOOD, ENVIRONMENTAL AND OCCUPATIONAL HEALTH & SAFETY
Maisons-Alfort, 19 October 2010

Conclusions concerning the risk related to blue light

"...The arrival of LEDs on the lighting market for the general public is an unprecedented development: it is the first time that sources classified in Risk Group 2 have become accessible to the general public, for use in the home and, most importantly, with no indication of the risk.
The same LED considered individually or integrated in a lighting system could be assigned to different Risk Groups depending on the evaluation distance imposed by the NF EN 62 471 standard.

As the technology behind LED lighting evolves over the next few years, lighting performance is likely to improve considerably.
The risks associated with exposure to LED-based lighting systems are therefore likely to increase as the radiance increases..." (Link...)

See also
LED products billed as eco-friendly contain toxic metals, study finds (2013-05-20)
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How does light affect our brain’s performance? (2014-04-24)
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Blue light may fight fatigue around the clock (2014-02-14)
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Smartphones use can affect your sleep (2014-01-24)
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Like coffee, blue light keeps night drivers alert (18/12/2012)
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For more information
Neuroscience
Light-induced retinal damage using different light sources, protocols and rat strains reveals LED phototoxicity
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Inserm - Institut national de la santé et de la recherche médicale
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anses
Lighting systems using light-emitting diodes (LEDs): health issues to be considered
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LED – light-emitting diodes
Health effects of lighting systems using light-emitting diodes (LEDs)
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Complete report available only in French
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OPINION OF THE FRENCH AGENCY FOR FOOD, ENVIRONMENTAL AND OCCUPATIONAL HEALTH & SAFETY
in response to the internally-solicited request entitled:
“Health effects of lighting systems using light-emitting diodes (LEDs)”
Link...

MDN