From car lights and lamp posts to smart phones and television sets, LED lights are an integral part of our environment whether at home, at work or even outdoors.
Given our exposure to blue light from LED lighting, several organizations have raised alarms about its potential danger to our health.
Earlier in the month, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) issued a report with recommendations to help reduce exposure to blue light. According to the Agency, blue light has a toxic effect on the eye’s retina and perturbs our sleep-related biological rhythms. It recommends limiting exposure to LED lights, especially for children.
Defining blue light
Blue light is part of the electromagnetic spectrum that is visible to the human eye. It has a wavelength of between approximately 380nm and 500nm; making it one of the shortest, highest-energy wavelengths that we can see.
It is in the sunlight that reaches the Earth’s atmosphere and, because it has the smallest wavelength, it scatters more than the other wavelengths thus giving the sky the appearance of a blue colour. It is used by our bodies to help regulate our natural sleep and wake cycles. And, it is credited with helping to boost our alertness and sense of well-being.
LED lighting is a primary source for artificial blue light. They are found in our lamps, and as the price of these lights decreases, they have begun to replace the less efficient traditional light bulbs. LED lights are used to light our computers and television sets as well as our smart phones and tablets. LED lighting is found in our cars as well as in street lamps. But with our increased dependence on LED lighting, more attention has been given to its impact on our health.
Potential health risk
With our increased exposure to artificial blue lights, concerns have arisen regarding its safety. Some claim that blue light exposure may contribute to the destruction of cells in the retina or cause age-related macular degeneration which can lead to vision loss.
It may also, as claimed by ANSES, trigger problems with our sleep schedule. Our body interprets blue light as daylight and staring at screens emitted artificial blue light may trick our bodies into staying awake.
However, according to experts, the risks of light exposure to our eye health are due to brightness. Too much light can damage our eyes.
The IEC Technical Committee (TC) 76 has developed IEC 62471 to provide standardized techniques for the evaluation of potential radiation hazards that may be associated with various lamps and lamp systems. This International Standard gives guidance for evaluating the photobiological safety of lamps and lamp.It specifies the exposure limits, reference measurement technique and classification scheme for the evaluation and control of photobiological hazards from all electrically sources of optical radiation, including LEDs.
It provides a classification of the safety of lighting on a scale of 0 to 3 with those classified as “0” or “1” considered low-risk and those classified as “2” or “3” considered as high risk and requiring the use of safety gear. In its recommendations, ANSES calls for the LED lighting systems with a classification of either “2” or “3” to be limited in their availability to the general public.
IEC TC 34 developed a technical report, IEC TR 62778, to provide guidance concerning the assessment of blue light hazard of lighting products. It also gives a summary of recommendations to assist the consistent application of IEC 62471 to light sources for the assessment of blue light hazard.
While further research may be necessary to fully understand the impact of long-term blue light exposure on our health, IEC Standards can help measure, and thus, evaluate their safety.