The Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) examined recently collected data and performed case studies to evaluate potential risks to human health of LED emissions. The SCHEER published their findings in a lengthy preliminary report.
Overall, the SCHEER concluded that normal use of LED lamps and displays by the general healthy population does not cause adverse health effects, according to available evidence. This review has also identified certain knowledge gaps about potential risks to human health.
Possible Circadian Disruption
Some evidence suggests that exposure to light in the late evening, including that from LED lighting or displays, may disrupt circadian rhythm. The amount of the circadian disruption depends upon the wavelength spectrum of the light. And not all LED lights produce the same spectrum of light. So far, studies have not proven if this disturbance of the circadian system leads to adverse health effects.
SCHEER Examined Evidence for Vulnerable Populations Separately
The Committee looked separately at the evidence among vulnerable populations including young children, adolescents, and the elderly. The Committee noted that children have a higher sensitivity to blue light. Although emissions may not be harmful, blue LEDs (between 400 nm and 500 nm) may be very dazzling and may induce glare (photochemical retinopathy). Glare is of particular concern for children below three years of age.
The elderly population may experience discomfort due to exposure to blue LED displays. For example, destination displays on the front of buses may be blurry for elderly viewers due to their particular sensitivity to blue light and its resulting glare.
Conclusions of Animal and Cellular Studies Difficult to Relate to Human Exposure
The SCHEER noted that while animal and cellular studies show adverse effects particularly in susceptible populations, their conclusions come from exposure conditions that are likely greater than those achieved with LED lighting systems. Such conclusions are therefore difficult to relate to human exposures.
SCHEER Recommends Close Monitoring of Long-Term Exposure Effects
Since the use of LED technology and its uses are still evolving, the Committee says that it is “important to closely monitor the risk of adverse health effects from the long-term LED usage by the general population.”