Indications of possible brain-tumour risk in mobile-phone studies: should we be concerned?
- 1Centre for Research in Environmental Epidemiology (CREAL), Municipal Institute of Medical Research (IMIM), CIBERESP, Barcelona, Spain
- 2Cancer & Radiation Epidemiology Unit, Gertner Institute, Chaim Sheba Medical Center, Tel-Hashomer 52621, Israel and Sackler School of Medicine, Tel-Aviv University, Israel
- Correspondence to Professor Elisabeth Cardis, CREAL, Doctor Aiguader 88, 08003 Barcelona, Spain;
- Accepted 27 September 2010
- Published Online First 24 January 2011
- Mobile phones
- brain tumours
- radiofrequency fields
- electromagnetic fields
Mobile-phone use has increased dramatically in most countries since its introduction in the early to-mid 1980s. The expanding use of this technology has been accompanied by concerns about health and safety. In the late 1990s, several expert groups critically reviewed the evidence on health effects of low-level exposure to radiofrequency (RF) electromagnetic fields, and recommended research into the possible adverse health effects of mobile telephone use.1–4 As a result, a number of studies have been conducted,5–14 including a large 13-country collaborative study, Interphone, with over 2700 glioma and 2400 meningioma cases and their matched controls, which was recently published.15
Studies on the health effects of mobile phones are very complex, and interpretation of the results necessitates understanding and careful consideration of various aspects including the timing of the study, the exposure variables of relevance and the influence of methodological limitations. Indeed, the results of studies to date, in particular those of the recently published Interphone international analyses,15 have been interpreted differently by various groups: some have taken them to suggest that mobile phones are safe, others that they cause tumours, while some have suggested that the limitations of the studies were such that no conclusion could be drawn.
This editorial discusses the main issues in the interpretation of the findings reported in recently published studies of brain tumours in relation to mobile-phone use, particularly the largest of these, Interphone, and their potential public-health implications.
Timing of the study
Most published studies to date have found no increased risk (and in many instances even a decreased risk) associated with ever having used a mobile telephone. These studies, however, were conducted at a time when mobile communication was still a relatively new phenomenon with low levels of use compared with today. As an illustration, though the largest study, Interphone, started in 2000, …