Are LED lights safe for human health?
This summary of the scientific Opinion on 'Potential risks to human health of Light Emitting Diodes (LEDs)' by the Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) covers some of the Opinion's key points and goes more in depth than the one-page factsheet on the same topic, also available on this website. An abstract and a shorter but more technical summary are also included in the scientific Opinion itself. Information about data and methodology and the science behind LEDs and eye and skin optics are also found in the Opinion and are not covered here.
4.1. What was the SCHEER's overall conclusion concerning possible health risks from exposure to LED lights?
The SCHEER concludes that there is no evidence of direct adverse health effects from LEDs in normal use by the general healthy population. The Committee noted, however, that either discomfort glare or disability glare can be temporarily caused by LED lights used in vehicles, particularly daylight running lights and headlights and that LED lights may have an effect on the sleep/wake cycle.
All light sources affect the circadian rhythms, but more research is needed to ascertain the specific impact of LED lights on the sleep/wake cycle, and also to determine if disturbances to the circadian system lead to adverse health effects.
4.2. What kind of research is still needed?
The review of the published research - conducted by the SCHEER - has led to valuable conclusions and identified certain gaps in knowledge on potential risks to human health from LEDs. There is insufficient knowledge about the actual exposure of people to optical radiation from LED sources and the total exposure from all optical radiation sources. Information about the exposure of the general healthy population is needed for assessing the potential health effects. It is suggested that exposure assessments look at specific age groups, babies, young children, adolescents, adults and the elderly.
High luminance, flicker, phantom array and stroboscopic effect are other factors relevant to risk assessment that need to be addressed in further studies. In particular, it should be established if some population groups are more susceptible to modulated emissions from LED lamps, either due to the design of the LED drive circuit or through the use of dimming circuits. The use of high luminance vehicle lighting should be investigated to determine if there are potential adverse consequences for increased accident rates.
Cumulative exposure to optical radiation over a 24-hour time period should be considered and further research should look into the reported effects of long-term, low-level exposure on age-related macular regeneration.
Some studies using LEDs on cells and animals did show some negative effects, particularly in vulnerable groups, but these tests were done using exposure conditions that far exceeded those of normal use and which would be difficult to replicate in humans.
Research should also be carried out on the effects of LED lights on healthy skin and the circadian system. Research should look at heat effects on the skin and the relation to skin cancer, if the use of infra-red saunas and warming cabinets use infra-red LED light sources. In addition, exposure and dose levels for the induction of effects for patients with certain types of photo-dermatoses should be investigated. As regards the circadian system, it is important to establish if and how artificial light, in general, affects the circadian system compared to natural light sources.
In addition, many LEDs contain toxic substances. In order to assess any potential health effect, further research is needed on waste management. In normal use, there is no evidence of harm from these toxic substances, since they do not leach from LED modules.
Since the use of LED technology is still evolving, the SCHEER would like to see continued monitoring of the risk of adverse health effects to the general public from long-term LED use.