The question of whether cell phones cause cancer has been studied extensively. The International Agency for Research on Cancer (IARC) considers cell phones to be “possibly carcinogenic to humans” despite overwhelming evidence to the contrary.
Cell phones were invented in 1973, but their use was not widespread until the 1990s. There are now more cell phones worldwide than people, with 8.58 billion cell phone subscriptions in 2022 compared to a population of 7.95 billion.
ACSH wrote a four-part series, Do Cell Phones Cause Cancer? in 2021, to refute a report from the Environmental Working Group (EWG) that cell phones pose a cancer risk to human health. With the almost ubiquitous use of cell phones, it is reassuring that recent studies confirm our conclusions from three years ago: cell phone use is safe and not harmful to human health.
Background
As explained in Radiofrequency Radiation and Cancer, radiation is a broad term that refers to the transfer of energy from one place to another. However, only the highest energy radiation (ultra-violet, x-rays, and gamma radiation) has enough energy to remove an electron from an atom, creating ions that could potentially start the process that could lead to cancer (ionization). Most of the energy in the universe, everything less than that of ultraviolet, including radiofrequency radiation emitted by cell phones, does not have enough energy to ionize atoms and cause cancer.
Common sense tells us that if there were an association between brain and other head and neck cancers and cell phones, we would expect to see a significant increase in these types of tumors over the last few decades. However, this is not the case. The National Cancer Institute reports stable incidence rates of:
- Adult gliomas in the U.S., Scandinavian countries, and Australia over the past several decades.
- Pediatric brain tumors in the U.S. during 1993-2013.
- Nonmalignant acoustic neuroma and meningioma in U.S. adults since 2009.
Recent Studies: 2022 - 2024
Systematic review
The Systematic Review of Human Studies, the largest review study to date, was commissioned and funded by the World Health Organization (WHO) and the New Zealand Ministry of Health. The review examined 63 studies published between 1994 and 2022, with participants from 22 countries. The review found, with moderate certainty, no association between cell phone use and brain tumors (glioma, meningioma), acoustic neuroma, pituitary tumors, and salivary gland tumors in adults or brain tumors in children.
COSMOS Study
The COSMOS study (Cohort Study of Mobile Phone Use and Health), a joint project between IARC and institutes from Sweden, the UK, Denmark, and the Netherlands, studied 250,000 users of cell phones, many with 15 years or more of regular cell phone use. The study reported that people with the most total hours of cell phone use did not have a higher risk of developing brain tumors than those with lower cell phone use. The authors stated that
“We found no evidence that long-term or heavy mobile phone use is associated with the risk of glioma, meningioma, or acoustic neuroma… Our findings to date, together with other available scientific evidence, suggest that mobile phone use is not associated with increased risk of developing these tumours.”
UK Million Women Study
Funded by Cancer Research U.K., the study recruited 1.3 million women born between 1935 and 1950. In 2001 and 2013, 776,156 women completed surveys on their cell phone use. After 14 years of follow-up, they report,
“Our findings support the accumulating evidence that cellular telephone use under usual conditions does not increase brain tumor incidence.”
Older Studies
Danish Cohort Study (2001)
The Danish Cohort Study, funded by the Danish Ministry of Health, studied more than 420,000 Danish citizens whose first cell phone subscription was between 1982 and 1995. The study found no evidence of increased cancer risk, including brain and nervous system, salivary gland tumors, acoustic neuroma, eye tumor, or leukemia, among either short-term or long-term (greater than ten years) cell phone users.
Interphone Study (2010)
Funded by the European Union and participating countries, this was a large case-control study of cell phone use and its association with head and neck tumors. The data came from questionnaires from European, Israel, Canada, Australia, New Zealand, and Japan participants.
“Overall, no increase in risk of glioma or meningioma was observed with use of mobile phones. There were suggestions of an increased risk of glioma at the highest exposure levels, but biases and error prevent a causal interpretation.”
IARC
IARC, part of the WHO, publishes monographs on carcinogenicity. [1] In 2011, IARC classified radiofrequency electromagnetic fields as “possibly carcinogenic to humans” based on increased risk of glioma – a type of brain cancer. As stated in the IARC Monograph, this classification was based on limited evidence in humans and animals. Although the vast majority of studies showed no increased cancer risk from cell phones, IARC based its “possible carcinogen” classification on questions concerning the INTERPHONE study.
However, in 2014, IARC issued a somewhat contradictory statement
“A large number of studies have been performed over the last two decades to assess whether mobiles phones pose a potential health risk. To date, no adverse health effects have been established as being caused by mobile phone use.” [emphasis added]
What Do Other Organizations Say?
Most organizations have not reported a link between cell phone use and cancer:
- FDA says that “there is no consistent or credible scientific evidence of health problems caused by the exposure to radiofrequency energy emitted by cell phones.”
- The Federal Communications Commission states that currently, there is no scientific evidence that establishes a definitive link between wireless devices and cancer.
- The European Commission on Emerging and Newly Identified Health Risks concluded that there was no association between cell phones and an increased risk of brain tumors or other tumors of the head and neck region.
Why does IARC refuse to acknowledge the overwhelming scientific evidence and clearly state that cell phones do not cause cancer and change their classification from “possibly carcinogenic to humans”? Because IARC considers everything to cause cancer, including drinking coffee and very hot beverages, working the night shift, and eating red meat. IARC’s own research has confirmed that cell phone use is safe, and the public has a right to a clear, definitive statement that cell phones do not cause cancer.
With cell phones now an essential part of everyday life, it's reassuring that extensive research continues to show no link between cell phone use and cancer. Studies from organizations worldwide have consistently supported the conclusion that mobile phones do not pose a cancer risk, even with long-term and heavy use. As scientific evidence mounts, it's clear that we can enjoy the convenience of our devices without fear of harm, setting aside outdated concerns about the impact on our physical health.
[1] They classify chemicals into four groups:
- Group 1: the agent is carcinogenic to humans
- Group 2A: the agent is probably carcinogenic to humans
- Group 2B: the agent is possibly carcinogenic to humans
- Group 3: the agent is not classifiable as to its carcinogenicity to humans.
IARC’s classifications have been used in U.S. class-action lawsuits as a determining factor that a substance causes cancer.
