Directorate-General for Health and Food Safety
3. Can mobile phones cause cancer?
- 3.1 Can mobile phone use increase the risk of brain tumours?
- 3.2 Have experimental studies revealed an increased cancer risk?
- 3.3 Have studies on cell cultures revealed genetic effects?
3.1 Can mobile phone use increase the risk of brain tumours?
There are mogre than 7 billion mobile phones in use today. Credit: Juha Blomberg
Figure 5. Observed glioma incidence rate in the Nordic countries and expected rates assuming mobile phone
Whether the use of mobile phones is associated with an increased risk of brain tumours has been the research question of numerous small and a handful of large-scale epidemiological studies. Attention has focused on the possibility of tumours of the head and neck region because these tissues are primarily exposed to the RF fields emitted by hand-sets. Furthermore, some studies suggested a possible association between the exposure to RF EMF produced by mobile phones and an increased risk of cancer of the auditory acoustic nerve (acoustic neuroma) and brain tumours (glioma).
However, the results of cohort and incidence time trend studies do not support an increased risk for glioma. The possibility of an association with acoustic neuroma remains open. In particular, the observed rate of glioma incidence in the Nordic countries has been compared to the predicted rates that would have been observed if there were an increased risk of 1.2, 1.5 and 2 related to a regular mobile phone use of 10 years or more. The observed cancer incidence does not show the predicted steep increase that would be expected if there were a causal link between mobile phones and cancer.
The fact that the rates of incidence of the corresponding tumours have not increased since the introduction of cell phones suggests thus precaution on the interpretation of such a hypothetical association.
3.1.2 Epidemiological studies do not indicate increased risk for other malignant diseases including childhood cancer. A number of studies also looked into the potential cancer risk of exposure to radio frequency fields from transmission towers. In most cases, no conclusions on a cancer risk could be drawn.
3.2 Have experimental studies revealed an increased cancer risk?
A considerable number of well-performed in vivo studies using a wide variety of animal models have been mostly negative in outcome. Among these, a number of lifetime and long-term RF fields exposure studies were performed on laboratory animals by exposing them to 900 MHz GSM signals and other higher frequency signals at higher exposure levels than in earlier studies. All studies concluded that there was no effect of RF fields on the risk of developing tumours, even at the higher exposures. One study found a reduced survival rate in exposed animals, but this finding remains unexplained.
The results of the new experimental studies are consistent with results from previous studies and, overall, add to the evidence that the RF fields such as those emitted by mobile phones do not cause cancer in laboratory animals.
3.3 Have studies on cell cultures revealed genetic effects?
An analysis of 88 in vivo and in vitro studies published between 1990 and 2011 and assessing genetic damage in human cells exposed to RF showed that the magnitude of difference between RF- exposed and sham-exposed controls was small with some exceptions. Globally, these studies did not provide evidence for any effect of radio frequency field on the genetic material of cells.
Other potential effects were also investigated, such as cell death, expression of genes, of cell proliferation. Most of the studies did not find any effect.