The Grapevine

Your Smartphone Emits Blue Light That Likely Accelerates Onset Of Blindness

Researchers from the University of Toledo (UT) revealed how our eyes can be gradually damaged over time as a result of being exposed to blue light.

The study titled "Blue light excited retinal intercepts cellular signaling" was published in the journal Scientific Reports on July 5. 

This type of light performs the function of regulating our sleep cycle, by helping us wake up during the daytime. But excess exposure from artificial sources during the nighttime can have a negative impact.

Over the years, blue light has become more omnipresent in our lives due to our increasing dependence on technology. While blue light is typically linked to smartphones and computers, we are also exposed to it from sunlight, fluorescent light, compact fluorescent light bulbs and LED light. 

"We are being exposed to blue light continuously, and the eye's cornea and lens cannot block or reflect it," said Dr. Ajith Karunarathne, assistant professor in the UT Department of Chemistry and Biochemistry.

Age-related macular degeneration (AMD) is a condition characterized by the death of photoreceptor cells in the retina of our eyes. It is among the leading causes of blindness with more than two million new cases being reported in the United States on an annual basis.

In their new experiments, the research team observed how blue light exposure triggers a reaction in a chemical called retinal which can generate poisonous chemical molecules in the photoreceptor cells.

"It's toxic," said Kasun Ratnayake, a Ph.D. student researcher who worked in Karunarathne's group. "If you shine blue light on retinal, the retinal kills photoreceptor cells as the signaling molecule on the membrane dissolves."

Companies have certainly been taking notes as many smartphones now provide the option of blue light filters, either as a part of the mobile operating system or in the form of third-party apps.

Apart from reducing screen time and taking enough breaks from it, experts also recommend wearing sunglasses that filter out blue light. People are also advised to avoid staring at their screen devices in a dark room or using them at high levels of brightness that cause eyestrain.

Karunarathne hoped the new findings would help in the design and creation of therapies to slow down AMD, such as a new kind of eye drop. The team already identified a Vitamin E derivative (known as alpha-tocopherol) which could have a protective effect and stop the death of the cells. 

Light sourced from television, cell phones, and tablet screens is also being measured for further study by his team. "By learning more about the mechanisms of blindness in search of a method to intercept toxic reactions caused by the combination of retinal and blue light, we hope to find a way to protect the vision of children growing up in a high-tech world," he added.