You might have heard speculation that electromagnetic radiation from mobile phones and wireless technologies is dangerous.

The radio waves wireless technologies transmit are very weak. They do not have enough energy to damage DNA and are very unlikely to cause cancer. Nevertheless, researchers are continuing to monitor whether there are any potential long-term health risks of phone use.

A new study provides comprehensive evidence that mobile phone use is not linked to cancer. The study is the largest review on the topic to date and is one in a long line of research showing that wireless technologies do not harm the human body.

"For the main issue, mobile phones and brain cancers, we found no increased risk, even with 10+ years exposure and the maximum categories of call time or number of calls," said Mark Elwood at the University of Auckland in New Zealand, who was a co-author in the study.

The review was commissioned by the World Health Organization (WHO) and published in Environment International.

No increased risk of brain cancer from mobile phone use

The review, which stemmed from concerns that phones held against the head emit radio waves into the brain, analyzed more than 5,000 studies, focusing on 63 studies from 22 countries most relevant for their analysis. 

"For this report, cancers of the brain (three types, and in children), pituitary gland, salivary glands, and leukemias were included," said Elwood.

None of the studies assessed in the review showed an increased risk of brain cancer with mobile phone use.

"The evidence did not support an increased risk of cancers from the use of mobile phones. Furthermore, there was no evidence to support any risk from broadcasting transmitters or base stations," said Keith Petrie of the Department of Psychological Medicine, at the University of Auckland, in a press statement.

How do mobile phones work?

Mobile phones and wireless tech exchange signals using radiofrequency (RF) waves. This is a form of energy in the electromagnetic spectrum, which is why mobile phones are sometimes said to give off electromagnetic radiation.

Electromagnetic radiation sounds dangerous, right? Well, not necessarily. It depends on how much energy the radiation contains. 

Radiofrequency waves used by mobile phone networks are a form of non-ionizing radiation. Non-ionizing radiation uses tiny amounts of energy to transmit data, nowhere near enough energy to damage the human body or DNA (genes).

And it's true for all types of mobile phone networks. WiFi, 4G, 5Gand Bluetooth all rely on radio waves to transmit data, as do FM radios. Each type uses a different frequency of radio waves, but none have enough energy to heat body tissues or damage cells or DNA.

Radiofrequency waves are different from ionizing types of radiation, such as X-rays, gamma rays and ultraviolet (UV) rays. Ionizing radiation contains much more energy and can damage DNA, which is why high levels of sun exposure can cause skin cancers.

There are also concerns that keeping a phone in your pocket or leaving the WiFi router on might be dangerous, but these myths have been debunked for the same reason: radio waves don't cause cancer.

When we stand outside on a cloudy day, we are actually exposed to more DNA-damaging rays than we get from having a mobile phone in our pocket or leaving the WiFi router on at night.

Mobile phones don't cause causer, but can we prove it?

Worries about the health effects of new technologies are common, especially when online conspiracy theories are involved.

"This was seen during the COVID-19 pandemic when people attacked cell towers believing a baseless theory that 5G towers spread the coronavirus," said Petrie.

The evidence is clear that the radio waves emitted by mobile phones and wireless technology don't have enough energy to damage the body directly.

The scientific consensus has remained strong. So far, no studies have found links between mobile phone use and cancer, so we can be very confident that wireless technologies do not cause cancer.

Nevertheless, many health care and scientific organizations don't have official positions on whether or not radiofrequency waves from phones cause cancer.

The problem is the philosophical conundrum of finding evidence of the absence of something. It's like when people argue that there is no God because there is no evidence of God. But what if we just haven't found evidence of God yet?

This issue of showing evidence that wireless technology doesn't cause cancer works the same way. Wireless technology is a significant part of our daily lives, so health care and government agencies are still addressing their safety.

Overall, the data overwhelmingly shows that using mobile phones and wireless tech is completely safe for our bodies. 

Edited by: Davis VanOpdorp

Primary source:

Lagorio, S et al. "The effect of exposure to radiofrequency fields on cancer risk in the general and working population: A protocol for a systematic review of human observational studies." Environment international vol. 157 (2021): 106828. doi:10.1016/j.envint.2021.106828