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Can talking on a mobile phone be hazardous to your health? It is difficult to know for sure. Some research suggests that heavy users of mobile phones are at a greater risk of developing cancerous brain tumours. However, many other studies suggest there are no links between cancer and mobile phone use.

The main problem with the current research is that mobile phones have only been popular since the 1990s. As a result, it is impossible to study long-term exposure to mobile phones. This concerns many health professionals who point out that certain cancers can take over twenty years to develop. Another concern about these studies is that many have been funded by the mobile phone industry or those who benefit from it.

Over five billion people now use mobile phones on a daily basis, and many talk for more than an hour a day. Mobile phone antennas are similar to microwave ovens. While both rely on electromagnetic radiation (EMR), the radio waves in mobile phones are lower in frequency. Microwave ovens have radio wave frequencies that are high enough to cook food, and they are also known to be dangerous to human tissues like those in the brain. The concern is that the lowerfrequency radio waves that mobile phones rely on may also be dangerous. It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.

Some researchers believe that other types of wireless technology may also be dangerous to human health, including cordless phones, wireless gaming consoles, and laptop or tablet computers with wireless connections. They suggest replacing all cordless and wireless devices with wired ones where possible. They also say that many cordless phones can emit dangerous levels of Electromagnetic Radiation even when they are not in use. They even suggest keeping electronic devices such as desktop and tablet computers out of the bedroom, or at least six feet from the head while we're sleeping.

A growing number of health professionals worldwide are recommending that mobile phone users err on the side of caution until more definitive studies can be conducted. They use the example of tobacco to illustrate the potential risks. Many years ago, people smoked freely and were not concerned about the effects of cigarettes on their health. Today, people know that cigarettes cause lung cancer, though it is still unknown exactly how or why. Some doctors fear that the same thing will happen with mobile phones. In May 2016, the UK's Independent newspaper reported on research by the US government's National Toxicology Program that showed a slight increase in brain tumours among rats exposed to the type of radio frequencies commonly emitted by mobile phones. This doesn't prove that mobile phones can cause brain tumours in humans, but it does show that it's possible. As a result, many experts now recommend texting or using head sets or speaker phones instead of holding a mobile phone to the ear.