Topic 146

Social impact on health of the use of mobile devices by HeeJun Sun

Everyday people use thier mobile devices. Mobile devices are the machines that can be carried around. Mobile phones, laptops and PDAs are common examples. As time goes, many people prefer using such mobile devices. Especially the population that carry a cell phone is increasing rapidly. The major reason why people like mobile devices is that it is "mobile"- they can bring the device anywhere without any restriction.

As people started to inquire whether using mobile devices harms the health of the people, there have been many researches and some are being done at the moment when you are reading this essay on your laptop or computer. Despite a lot of researches, researchers differ in their opinions. Some claim mobile devices harm users' health and others do not. Who is right and who is wrong? Let's consider mobile phones as an example because most people hear news about the relationship between health and use of cell phone quite often. In fact scientists and doctors have done a vast amount of research about the impact of the use of mobile phones on health. To know if mobile phones affect our health first we have to know how it works.

Like all other radio communication devices, mobile phones use radio waves that travel with the speed of light to carry the information, like voice, text and images, through the air. Radio waves are a kind of electromagnetic fields that are present in our every day life, both naturally and from man-made sources. Different types of electromagnetic fields have different frequencies. Visible light, for instance, has higher frequencies than radio waves, but lower than ultraviolet light. Electromagnetic waves with frequencies higher than ultraviolet light are called ionizing radiation, which has sufficient energy to break molecular bonds and damage human tissue. X-rays and gamma rays are examples of ionizing radiation. Radio waves belong to the lower frequency part of the electromagnetic spectrum, which is called non-ionizing radiation. In the lower frequency part the electromagnetic energy is too weak to break molecular bonds.

What happens when a person uses a mobile phone? When a person is exposed to the radio waves from mobile phones, most of the energy will be reflected by the body or travel around it. Some of the energy, however, will be absorbed in the tissues at the surface of the body. Inside the body certain molecules, like water, will start to vibrate due to the electromagnetic fields. By "friction" the energy is converted into heat. If the radio wave intensity is very high, the heating may be significant and harmful. But, as I have mentioned earlier, the power( radio waves that belong to the lower frequency part) used by mobile phones is very low so the tissue heating due to radio wave is too small to be noticed. However, mobile users sometimes feel quite noticible heat after a long phone call. This is not caused by radio wave heating but by the phone itself getting warm during a call.

Some sensitive medical equipment, including cardiac pacemakers, may get affected by electromagnetic fields. However, such devices in recent days have improved so much that the risk that a mobile phone may have an impact on them is very small. Although having better condition of the device, pacemaker users are recommended to keep a distance of 15 cm between their mobile phone and the pacemaker to avoid the risk of electromagnetic interference.

As we can see the use of mobile devices does not have a harmful impact on our health. In fact, WHO and other expert groups have concluded that the scientific evidence does not demonstrate any health effects associated with the radio waves from mobile devices such as mobile phones. Therefore, we do not have to worry too much about using cell phones or labtop.