LED lights are energy efficient, which means they often replace incandescent lamps and halogens. But these lamps emit a rich light in short waves, the blue light. We are therefore more and more exposed to the blue light of the lights, but also to that emitted by the screens of computers, smartphones and tablets.
In 2010, ANSES carried out an expertise to evaluate the health consequences of this exposure to blue light. This already highlighted the dangers for the retina, which led to the general public level 0 or 1 LED risk lamps. But since 2010, new scientific data have been published. The health agency therefore presents an update of its recommendations through the analysis of 600 scientific publications.
Did you know ? The first blue LED was invented in 1992. Previously, there were only red, yellow or green LEDs. In 2014, the Nobel Prize in Physics was awarded to researchers who developed blue LED.
Recent studies confirm the dangers of blue light for eyesight: Exposure to this light reduces visual acuity and increases the risk of age-related macular degeneration (ARMD) in the long term. Some lights seem more harmful, such as car headlights, flashlights, decorative LEDs, spotlights and even some toys.
In addition, the agency highlights the risks associated with an exhibition in the evening. Indeed, light plays a role in controlling our biological rhythms: the production of melatonin, often called the "sleep hormone", depends on the day / night rhythm. That's why night lights can disrupt our biological clock.
Limit screens in the evening before bedtime The blue light in the evening, even in small doses, would delay the production period of melatonin and disrupt our circadian rhythm, with consequences on sleep. For ANSES, we must limit the use of LED devices in the evening, especially among young people, children and adolescents. Indeed, in young people, the lens of the eye is clearer.
ANSES has also been interested in the problem of intensity variations in LEDs, which induce visual phenomena, such as flicker, which can lead to headaches and visual fatigue. Children, adolescents and some professionals may be particularly sensitive to these visual problems.
The general public is becoming aware of the dangers of blue light. This is why manufacturers offer anti-blue light filters for screens or glasses. But is it effective?
"Regarding the means of protection available to the general public such as treated lenses, protective glasses or specific screens, their effectiveness against the effects on the retina of blue light is highly variable," says ANSES. Moreover, their effectiveness in preserving circadian rhythms is not proven today. "
Finally, due to the adverse effects of night lighting on ecosystems, the agency recommends reducing light pollution, including that due to LED lighting.