LED lights are easy on the pocket, since they are energy efficient, but there is a down side to using them. Spending long hours under LED lights and bulbs can lead to serious health implications, such as migraines. A March 2019 indicative study by a laboratory based in Delhi, titled Impact of Flicker in LED lights on Human Eye and Health in General, suggests that “exposure to flicker emitted by LED light leads to poor eye health, and its prolonged usage may cause significant problems to human health”. In the study, respondents were exposed to five LED lights from leading manufacturers in the country over a number of days. At the end of nine days, it was found that close to 40 respondents who were exposed to the light complained of headache and eye strain, which was not attributable to any other physical factors. Also, 24% of the total respondents felt stressed, while 22% of respondents felt anxious.
Even low frequency has negative effect on human beings
The key observation made by the study was that respondents who were exposed to the light with the least flicker rate got fewer headaches when compared to those exposed to a high flicker rate. According to US Institute of Electrical and Electronics Engineers (IEEE), the healthiest light is one that does not flicker, like the natural daylight . Even a frequency of 100-400 Hz, at which many LED luminaires operate, has negative effects on people, especially on the human eye. Studies have also reported that children are more vulnerable than adults to flicker-induced ill effects. Flicker in certain industrial settings can cause performance issues, and even accidents. Factors that make flicker worse are the longer duration of exposure. “It is difficult to pinpoint, but, yes, bright flickering lights can trigger migraines, and result in fatigue and stress. I see a lot of cases, in which the migraine is not of the classic case, but one associated with bright lights, either from LED lights at the workplace or that emitted from computer screens,” says Dr Dipali Prabhu, an ophthalmologist. “They increase the risk of cataract and age related macular degeneration which is a vision threatening condition. LED lights emit the short wavelength blue light which damaged the retina . So, it’s important to take care while using TV computer mobile as all these have led back light,” says Dr Shalini M, an Opthalmologist.
Manufactures blind to ill effects due to production costs
Despite being aware of this, why are LED lights being manufactured and used on a large scale? An R&D researcher working at a LED manufacturing company, who does not wish to be named, says, “Manufacturers are aware of the harmful effects of the flicker in LED lights, but not much is being done, because of the cost of manufacturing. Adding an extra circuit to control flicker or remove it from lights and bulbs is costly and requires expertise, which all adds to the cost of production. There is no control on the manufacturing of such lights, so the government needs to set standards and control the sale.”
LED lights to meet the photobiological safety standards
Elaborating on the control required for the manufacture of such lights, Dr Chandrakant S Pandav, a public health expert, says, “Artificial lighting is an integral part of our lives. We spend an average of 10-12 hours under these lights, and with the government promoting LED lights, it is important that they meet the photobiological safety standards prescribed internationally. This is more so because LED lights available in the Indian market have a very high flicker rate that is harmful for eye health.” Talking about control, Dr Harbans Lal, a Senior Ophthalmologist adds, “Unfortunately, there are no standards in India and most LEDs have flicker rate of anything between 40% to 80% much higher than the California benchmarks.”