Nanogirl Michelle Dickinson: Are mobile phones really bad for our health?

Mobile devices are a 'Class 2B carcinogen', says the World Health Organisation, but so too are coffee, pickles and being a carpenter. Photo / Dean Purcell

COMMENT:

5G is coming to New Zealand, and with the next mobile revolution seemingly endless opportunities for technological and business developments. While many of us are dependent on our smartphones to help connect us with the world, most of us aren't really sure how our phones work, what 5G is, and whether or not we should believe the health scares floating around social media.

"G" stands for Generation and if you look at your smartphone right now, it will probably display a 3G or a 4G symbol. This refers to the frequency band it uses to receive and transmit data. 4G is 10 times faster than 3G. 5G is predicted to be 1000 times faster than our current systems.

5G is simply the fifth generation of mobile internet connectivity. It differs to the previous generations through its use of higher frequencies, which enable its users to transfer wireless data faster. The improved speed will enable the creation of new technologies, for example, improving data transfer for smart cities, remote surgeries and autonomous vehicles, as well as super-fast downloads for playing virtual reality games and watching movies.

The frequencies we refer to in mobile phone technology are all radio signals, and often referred to as RF or Radiofrequency radiation. For most people, anything with the word radiation in it sounds scary. It's not as intimidating as it might seem though - the word just means the emission of energy from any source.

Too much exposure to radiation is thought to be bad for us, and linked to cancer. This is why we are advised to limit the number of medical x-rays we have a year. X-rays are a form of ionising radiation, and repeated exposure has been seen to damage our DNA, which over time has been shown to increase the risks of developing cancer.

Radiation is split into two broad categories: ionising and non-ionising. Non-ionising radiation doesn't carry enough energy to "ionise", or strip electrons from atoms and molecules. It therefore doesn't have enough energy to damage our DNA. The radiation emitted from radios, mobile phones, phone towers and Wi-Fi routers – RF radiation - is non-ionising. It sits at the low-energy end of the electromagnetic spectrum and is much safer than high-energy ionising radiation like x-rays.

With every new mobile phone release comes renewed concern around the effect of this technology on our health, and fears surrounding mobile phone use and the possible effect of radiation on the human body are ongoing. This isn't helped by the World Health Organisation declaring that mobile devices are a "Class 2B carcinogen", which really sounds scary. To put things in perspective, however, other items in the 2B category include coffee, pickles and being a carpenter.

The WHO says that about 25,000 scientific articles have been published on non-ionising radiation over the past 30 years making scientific knowledge of the technology more extensive than for most of the household chemicals we use day-to-day. Current evidence does not confirm the existence of any health consequences from exposure to low-level electromagnetic fields from mobile phones.

The great news is that although the power levels involved in mobile and wireless telecommunications are already incredibly low, as the frequency goes up the depth of penetration into biological tissues goes down. This means that 5G is even less likely to penetrate the body than the current technology that we use, so no need to invest in a new tinfoil hat.

5G is going to have a massive and exciting effect on people's lives and businesses. Of course, just as we start to get our heads around what it can do, scientists and engineers are already working on the next big mobile thing.

• Dr Michelle Dickinson, creator of Nanogirl, is a nanotechnologist who is passionate about getting Kiwis hooked on science and engineering. Tweet her your science questions @medickinson.