Photo of mobile phone and laptop

Do mobile phones, mobile phone masts, Wi-Fi or 5G cause cancer?

Last month we spoke about whether there were cancer risks from the electromagnetic radiation from power lines.  

Communications devices such as mobile phones rely on a slightly different aspect of electromagnetism associated with radiofrequency electromagnetic waves, so this month we’re going to look at the question as to whether mobile phones; the masts they connect to; Wi-Fi in our homes; and related new technology (such as 5G) might cause cancer.

Some background on communication devices

Radio frequency communications (such as Wi-Fi, mobile phones and new 5G technology) are based on a somewhat different aspect of electro magnetism to that around high voltage power cables. This technology is relatively new so it’s natural to have some concerns about health consequences.

Brain tumours have always occurred and rates of most forms of brain tumour remain largely constant. If one developed a brain cancer and a used mobile phone regularly, it would be rational to wonder if the tumour diagnosis could result from mobile phone use.

Early communication devices relied on proportionately large power outputs by the devices and transmitter masts. This is why early mobile phones similarly required proportionately large batteries to work. Major technological advances have resulted in modern devices operating at small fractions of the energy of earlier models. The drive to increase reliability and the charge interval on such devices combined with desires to reduce any possible safety issues for those in the immediate vicinity of transmission masts has resulted in vastly more efficient communications reliant on much lower energy transmission. We’ve had large scale public mobile phone technology for over 20 years and we know that those older mobile phones and masts which operated at higher powers don’t cause cancers so we can be even more confident that modern versions also pose no cancer risk.

What the research tells us

Mechanistically, on the whole, we know there is no increase in human cancers from communications devices from looking at cancer numbers over time. Experimentally we know of no fundamental biophysical or biochemical mechanism for these signals to interact with important cellular functions (such as DNA or enzymes). However, some animal experiments have given complex findings. Most notable is the US National Toxicology Programme study which exposed rats and mice to massive doses of power from, equivalent to early generation mobile phones, constantly over their whole lives. They found small increases in rates of heart cancer in male rats and possibly some increases in adrenal gland and brain cancers. However, there were no differences in female rats and no differences in male or female mice exposed to the same conditions. (By the way, they also found that the average animal in the mobile phone exposed group lived longer too.) Rats and mice also aren’t humans so it is hard to really extrapolate any findings conclusively to human beings anyway.

The cancer monitoring body of the World Health Organisation, the International Agency for Research on Cancer (IARC), had also looked at the available data and concluded that radio frequency electromagnetic fields were a possible carcinogen. It is important to understand that this category is used for agents for which there is limited evidence of carcinogenicity in either animals or humans, so “possible” in no way means that something does cause cancer, nor does it reflect the magnitude with which something could cause cancer. As already mentioned, there is some research in support of that but when taken as a whole, this categorisation and the rest of the available data indicates that there is simply no evidence to support worrying about phones, masts etc when talking about cancer risk. In addition, the changes to frequency used by technology such as 5G means that these signals cannot even penetrate the human body.


So bringing this and last month’s articles together, while there are lots of other issues we might worry about with new technology, cancer isn’t one of them. Cables and masts can be an eyesore, our overuse of phone technology can contribute to other societal issues but when it comes to cancer we might better focus our efforts on the real challenges in our community - the things we can do which are proven to reduce our cancer risk and the efforts we must all make to ensure everyone in our community gets the best chance of a good outcome during and after treatment.

If you'd like to learn more about reducing your cancer risk, The European Code Against Cancer was developed by the International Agency for Research on Cancer and the European Commission. Cancer specialists and scientists from across Europe compiled the code based on the latest scientific evidence on cancer prevention.