According to the Daily Mail, French health authorities say LED lights can cause permanent damage to the retina and disrupt our natural sleep rhythm.
The French Food Environment and Occupational Health and Safety Agency (anses) issued a warning that strong LED lights can cause "phototoxicity".
At present, LED lights have already penetrated into every aspect of our daily life. Under the guidance of energy-saving policies and the withdrawal of traditional lamps (incandescent lamps and traditional halogen lamps) from the lighting market, LEDs have been widely used in the fields of indication, decoration and general lighting due to their effective energy performance. It is also widely used in TV displays.
In such a common application scenario of LED lights, how should we reasonably view the warning "LED lights will cause permanent damage to the eyes" put forward by relevant agencies? How should we use LED lights in our daily life?
Let's first look at the specifics of the anses report.
The health effects of LEDs, mainly the effects of blue light on the eyes
In fact, the so-called health effects of LED lights mainly come from the effects of blue light on the eyes - which is also the focus of this anses report.
Speaking of blue light, many people have heard of it in their daily life. Many businesses will achieve the commercial purpose of marketing anti-blue light products by rendering the harm of blue light to human health, such as anti-blue light glasses, anti-blue mobile phone film, eye protection lamps and so on. In the background of Lilac Garden, readers often leave messages, raising their confusion about these anti-blue light products.
So, what exactly is Blu-ray? How does it harm the human body?
The so-called blue light refers to high-energy short-wave light with a wavelength between 400 and 500 nm, which is a component of natural light. Due to its technical particularity, LED can emit blue light in a short time, which has stronger illumination than other light sources.
Back in 2010, Anses pointed out that blue light in LEDs has toxic effects on the retina.
The latest report released by anses also clearly points out that all new scientific data obtained since 2010 supports the toxic effects of blue light on the eyes. Such toxic effects include short-term phototoxic effects associated with acute acute exposures, and long-term effects associated with chronic exposures, which may lead to decreased vision and increased risk of age-related macular degeneration.
In addition, experts pointed out that exposure to light sources with strong blue light at night can disrupt the biological clock and affect sleep. Due to the large changes in the light intensity of some LED lights, sensitive groups such as children and adolescents may be more susceptible to the potential effects of this light adjustment, such as headaches and visual fatigue.
However, this does not mean that we should put an end to all blue light and stay away from all LED devices.
Blue light has a positive effect, and its hazards also have a safe range
Blue light also has a positive effect on the human body.
Blue light with a wavelength of 455-500 nm can adjust biological rhythms, emotions, and memory, and has an important role in producing dark vision and affecting refractive development.
In addition, the hazards of blue light can be assessed.
At present, authoritative institutions, organizations and experts at home and abroad have conducted various tests and evaluations on the blue light hazards of LEDs, and have formulated the IEC62471 blue light safety standard. This standard is applicable to all light sources except lasers and has been widely accepted by various countries.
According to the standard, all kinds of light sources can be classified into zero-type hazard (gazing time>10000s), first-class hazard (100s≤gazing time<10000s), second-class hazard (0.25s≤gazing time<100s) and three-class hazard according to the gaze time (fixation time ≤ 0.25s).
Currently used as LED lighting, there are basically zero and one hazards, which are similar to other light sources and are all within the safety threshold.
According to the inspection of Shanghai Lighting Product Quality Supervision and Inspection Station (2013.12), among 27 LED samples from different sources, 14 belong to the non-hazardous category and 13 belong to the first-class hazard. These light sources and lamps are used in normal ways and are harmless to human eyes.
The anses report also pointed out that our commonly used "warm white" LED home lamps are no different from traditional lighting, and the risk of phototoxicity is very small.
However, the report also emphasizes that other types of LED lighting, such as flashlights, car headlights, decorations or toys, may be rich in blue light, which is a Class II hazard and is not within the safety threshold, so the eyes cannot stare.
Car headlights belong to the second category of hazards, and it is not advisable to stare directly at them
In addition, computer, smartphone and tablet screens are a significant source of blue light, and since children and teens are particularly sensitive groups whose eyes cannot filter blue light completely, their screen time should be limited.
Seeing this, I believe you already know the risks of LED and blue light.
what should we do? anses advice on LED usage
In order to reduce the possible negative effects of LED blue light on the human body, some of the suggestions given by anses are as follows.
It is recommended to use warm white (color temperature below 3000K) lamps for household lighting;
To prevent disruption of the biological clock, the public, especially children, are advised to reduce their contact with LED screens (mobile phones, tablets, computers, etc.) at night and before going to bed;
Restrict all LED system products to Class Zero and Class One Hazards of the Blue Light Safety Standard;
Limit the illumination intensity of car headlights while ensuring road safety.
As for the anti-blue light glasses or anti-blue light screens commonly used by the public, Anses said it is not recommended. The agency emphasizes that the products' effects on the retina vary widely, and their effectiveness in maintaining circadian rhythms has not been proven.
All in all, there is no need to worry too much about blue light and LED products. The key to protecting eyesight lies in good eye habits, avoiding long-term close reading, and ensuring sufficient outdoor activities.