Blue light from phone screens may gradually cause blindness – study

MANILA, Philippines – A group of researchers from the University of Toledo have discovered that exposure to blue light from digital device screens gradually damages vision and accelerate blindness.

Blue light is scientifically defined as short wavelength light belonging to the 400 to 495 nanometer range in the visible light spectrum, containing high amounts of energy. This light is said to potentially trigger the creation of poisonous molecules in the eye’s light-sensitive cells which speed up macular degeneration and loss of vision.

Macular degeneration is caused by the death of photoreceptor cells which lets us see by converting light into signals that are sent and processed in the brain. Some studies suggest that it is the leading cause of blindness, especially among older individuals. 

The researchers in the study added evidence to the belief that blue light is harmful. They exposed living cells to different types of light, and found that blue light stirred up reactions that lead to the creation of poisonous chemicals in the photoreceptor cells.

“If you shine blue light on retinal, the retinal kills photoreceptor cells as the signalling molecule on the membrane dissolves,” Kasun Ratnayake, one of the researchers told The Guardian. Retinal is a form of vitamin A necessary to our ability to see. 

He added that when photoreceptor cells die, they no longer regenerate.

“We are being exposed to blue light continuously, and the eye’s cornea and lens cannot block or reflect it,” Dr. Ajith Karunarathne, one of the researchers and assistant professor in the University of Toledo explained in a statement.

For people who want to protect their eyesight, they suggest wearing sunglasses that filter both UV and blue light.

While they commend some mobile phone companies for already adding blue-light filters to the screens of their devices, they still advise people to avoid staring at them in the dark.

The researchers also hope their findings can help develop new innovations in protecting our eyes from blue light.

“It’s no secret that blue light harms our vision by damaging the eye’s retina. Our experiments explain how this happens, and we hope this leads to therapies that slow macular degeneration, such as a new kind of eye drop,” Karunarathne said. – Rappler.com