If I were asked to name the most useful handheld device in every home in Nigeria today, I would say, it’s the mobile phone. A smartphone is a mobile phone that performs many of the functions of a computer. Typically, it has a touchscreen and it is capable of Internet access. The Nigerian Communications Commission (NCC) has revealed that the number of connected telephone lines in Nigeria is about 216 million (May 2016). The average Nigerian uses the phone several times a day. It isn’t therefore surprising that a number of users are asking questions about the safety and health challenges posed by these phones.
“Can looking at the computer screen damage my eyes?”, asked Yomi. Please, note that smartphones are mini computers. Some computer users have complained of uncomfortable eye-related symptoms such as eyestrain, dry eyes, headache, fatigue, difficulty focusing, blurred vision, seeing double, itchiness, gritty sensations and irritation in the eyes in addition to shoulder and neck pains after staring at their phone or computer monitors for hours on end. These are genuine complaints caused, not by the computer but, by an abuse or overuse of their eyes.
Focusing at anything (be it a digital device or a book) for long periods without taking a break at all would cause similar symptoms. This can be solved in three ways. First, try more frequently blinking. Secondly, shut your eyes for about one minute or take a look at a distant object every half hour. Finally, make sure you wear an appropriate pair of glasses (if you are supposed to) and ensure your phone or computer is at a suitable working distance. The preferred viewing distance is between 50 and 100 cm from your eyes. You may increase text size for smaller screens.
“How bright should my computer screen be?”, asked Toye. The brightness of the screen of your computer is generally not a major concern. It is good to keep your phone screen bright. This reduces the flicker rate of the computer and reduces fatigue, eyestrain and headaches.
Also, a bright screen causes your pupil to constrict, which gives you a greater range of focus, reducing the need for your eyes to accommodate and enabling you to work longer and with more comfort. It is, however, desirable to create equal brightness in the room or around your workstation to avoid a sharp contrast between your computer screen and the lighting in the room. This will help reduce eyestrain and make your task more comfortable.
“What about long-term damage? I have read that smartphones emit some radiations that can actually damage the eyes. Is it true?” asked Yomi again. It is not known for sure at this point if prolonged use of computer actually causes permanent damage to the eyes. Mobile phones, indeed, emit some electromagnetic waves (HEV light) also called blue light, because they use radio frequency to make and receive calls. At high levels, blue light can be extremely damaging to the various parts of the eyes including the cornea and the inner coat of the eye called retina. It can also cause cataract.
“Is it true that the levels of radiation are higher when the battery charge is low and during the recharging process?” There is no direct link between your smartphone battery charge level and handset transmit power level. A low battery level has no relationship to the current effective distance between handset and base-station. Consequently, your handset’s battery level indicator is not a useful indicator of the amount of “radiation” currently emitted by the handset (in talk mode).
This is what World Health Organisation (WHO) in 2014 has to say, “A large number of studies have been performed over the last two decades to assess whether mobile phones pose a potential health risk. To date, no adverse health effects have been established as being caused by mobile phone use.”
“Is it safe for children to spend long hours using smartphones and other digital devices?”, asked grandpa Areo. The long-term impact of digital devices on children’s eyes is not fully known. A recent study has found symptoms of dry eye disease to be more common in children who spent more time on smartphones and less time outdoors than their age-sex matched controls. Since children have a whole life-term ahead of them, it is reasonable to limit the use of digital devices to a few hours a day. Dry eye disease in childhood can adversely affect vision and school performance. WHO has promoted further research on this group. Several studies investigating potential health effects in children and adolescents are underway.
“How do I ensure that my eyesight is not affected by the use of smartphone?”, Davidson asked. I would advise you to get a comprehensive eye examination at least once a year, even if you feel you have no problem. Minor asymptomatic problems with your eyesight can increase your risk for digital eye strain. Remember, Glaucoma gradually destroys the eye without any warning until blindness almost creeps in. It is only detected at such an examination. If you are longsighted or above 40, you must use your glasses to prevent eyestrain when using your smartphone. If you spend long hours on your phone or other digital devices, you may require special eyewear specifically prescribed for your digital viewing needs.
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