"It's no secret that blue light harms our vision by damaging the eye's retina".
New research has described how molecules in the retina can become toxic when exposed to blue light and damage photoreceptor cells. The photoreceptors can not function without the presence of the retinal molecules. But the blue light by itself had no effect on the cells, neither did retinal that hadn't been exposed to blue light.
The researchers found that being exposed to blue light causes retinal to set a chain of reactions that leads to toxic chemical molecules to be created in the photoreceptor cells. They do not regenerate, so "when they're dead, they're dead for good", said Kasun Ratnayake, a PhD student researcher and another author of the study. Dr Ajith Karunarathne, an assistant professor in the university's department of chemistry and biochemistry explained that this blue light is constantly affecting the cornea and the lens that can not block or reflect it.
In the lab, the researchers combined retinal with various cells from the body, including photoreceptor cells, neurons, and heart cells.
The blue light tablets, smartphones, and laptops emit is so bright we can see our screens on a sunny day.
Experts say that blue light irradiation leads to the activation of the photosensitive molecules of retinal, which changes the state of the phospholipids involved in cell signaling pathways. "No activity is sparked with green, yellow or red light", Karunarathne said. "It can kill any cell type".
The researchers did find a molecule called alpha-tocopherol that can stop the cells from dying, but the natural antioxidant fails to protect older users who are more susceptible to macular degeneration. However, as a person ages or the immune system is suppressed, people lose the ability to fight against the attack by retinal and blue light.
"If you look at the amount of light coming out of your cell phone, it's not great but it seems tolerable", Dr.in the UT Department of Chemistry and Biochemistry, said.
If you want to protect your eyes, Dr. Karunarathne suggests wearing sunglasses/glasses that filter out harmful UV and blue light, using blue light filters on phones and monitors, and avoid using electronic devices with screens in the dark. "Some cell phone companies are adding blue-light filters to the screens, and I think that is a good idea". Blue rays of light, which have shorter wavelengths and more energy than other colors, can damage our eyes over time - they contribute to macular degeneration, the primary cause of blindness. Both were necessary to kill the cells.