ANSES (National Agency for Food Safety, Environment and Labor) has carried out the first expertise on the dangers of these lights, which are increasingly used because of their low power consumption and their very long service life. superior to other systems.
“In a few months, the number of LED bulbs accessible in supermarkets has multiplied dramatically,” said Dominique Gombert, director of risk assessment at ANSES, to AFP.
To obtain white light, a blue diode, corresponding to radiation of short wavelengths close to ultra-violet, is coupled to a yellow phosphor. It is "the simplest and cheapest technology", therefore used "in 90% of cases", according to Mr. Gombert.
Diode lights present risks to the eyes
However, this blue light is particularly dangerous for the retina, which is more sensitive to violet-blue light, since the various pigments present in its cells can induce a reaction causing oxidative stress injury.
This photochemical risk "generally results from low intensity repeated exposures over long periods", without filter, according to the agency.
Children "are particularly sensitive to this risk, insofar as their lens remains developing and cannot ensure its effective role of filter of light", says ANSES.
This blue light also has "aggravating" effects on a pathology common with age, age-related macular degeneration (AMD) and in people sensitive to light due to skin disorders or drug treatments. Chronic alcoholism is also a risk.
Another problem: the luminance of the LEDs, or quantity of light emitted per unit area, high due to the punctual nature of the emitting area. "These new lighting can lead to + light intensities + up to 1000 times higher than conventional lighting, thus generating a risk of dazzling", according to the agency.
The agency has evaluated the risks nine types of diodes available on the market, according to the existing standard for other lighting. On a scale from 0 to 3 (high risk), it found that a majority were risk-free or low risk, but that three diodes presented a risk of 2 level (moderate risk), with a maximum duration of exposure of at most a few tens of seconds.
In the years to come, "more and more LEDs will appear in risk group 2," the agency said.
Some professions are particularly at risk, such as lighting designers, extras and stage show technicians, surgeons or dentists (and their patients) and phototherapy professionals.
For now, ANSES recommends "to avoid sources of light (...) rich in blue color in places frequented by children", such as maternities, nurseries, or schools, or in objects that they use. Also watch out for car headlights!
For the general public, who can not differentiate at-risk LEDs from others, ANSES is asking manufacturers to rapidly label and market only low-intensity, safe LEDs.
Article published in several daily newspapers