Blue Light Poisoning

With the increased reliance on digital technology, people have found themselves on their devices much more. This constant exposure to blue light, especially at night, can have a multitude of negative effects on the body, often resulting in eye damage and sleep deprivation.

Natural blue light is found in the sun, though it gives off this light in much shorter wavelengths than digital devices. There is also artificial blue light, which is given off by LED and fluorescent lights, as well as digital screens like phones, computers, and TVs. Lately, it seems that people have been increasingly exposed to artificial blue light for longer periods of time.

“We are being exposed to blue light continuously, and the eye’s cornea and lens cannot block or reflect it,” Assistant Professor Dr. Ajith Karunarathne of the UT Department of Chemistry and Biochemistry, said.

The excessive exposure to blue light can suppress melatonin secretion in the body. Without melatonin, circadian rhythms are thrown off and it can cause poor sleep quality, irregular sleeping patterns, and sleep disturbances, which are all a part of chronic sleep deprivation.

“Most of the kids I know get like five to six hours of sleep on average because they’re on their phones until midnight texting or scrolling,” NHS freshman Ruby Tyrrell said.

Aside from sleep related effects, blue light can decrease attention span, reaction time, memory consolidation, and people’s overall sense of alertness. It also releases negative stress signals that can cause cellular damage in the eyes. A common example is the disease cataract, which makes human eyes yellow and foggy, and requires surgery to be fixed.

“It’s toxic. If you shine blue light on retinal, the retinal kills photoreceptor cells as the signaling molecule on the membrane dissolves. Photoreceptor cells do not regenerate in the eye. When they’re dead, they’re dead for good,” PhD student Kausun Ratnayake, researcher from the UT Department of Chemistry, said.

There are a number of ways to prevent damage. A popular method has been to wear blue light blocking glasses. The glasses are supposed to cut the light into shorter wavelengths that are less damaging to the eyes. However, there is very little scientific evidence to say that these glasses actually work. Nonetheless, many people still purchase them in hopes of protecting their eyes.

Some other methods to protect from blue light poisoning have been approved by the scientific community. One way is to look away from the screen you’re using every twenty minutes and look at a faraway object for 20-30 seconds.  There are also special screen filters that can be purchased to shield your eyes from the blue light. Another solution can be to simply use devices less at night.

“Try to set limits for yourself. An example being, try not to be on your phone after ten o’clock, or no more than three hours of screen time a day. It’s really more of a personal thing. Go with what you think works for you,” Tyrrell said.

Much more research and time will be required for scientists to fully understand the long-term effects of blue light. Right now, they believe that children are most at risk. This is due to the fact that children naturally have larger pupils than adults, and take in the light in greater quantities.

“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,” Karunarathne said.