Risk of brain tumours in relation to estimated RF dose from mobile phones: results from five Interphone countries

Abstract

Objectives: The objective of this study was to examine the associations of brain tumours with radio frequency (RF) fields from mobile phones.

Methods: Patients with brain tumour from the Australian, Canadian, French, Israeli and New Zealand components of the Interphone Study, whose tumours were localised by neuroradiologists, were analysed. Controls were matched on age, sex and region and allocated the 'tumour location' of their matched case. Analyses included 553 glioma and 676 meningioma cases and 1762 and 1911 controls, respectively. RF dose was estimated as total cumulative specific energy (TCSE; J/kg) absorbed at the tumour's estimated centre taking into account multiple RF exposure determinants.

Results: ORs with ever having been a regular mobile phone user were 0.93 (95% CI 0.73 to 1.18) for glioma and 0.80 (95% CI 0.66 to 0.96) for meningioma. ORs for glioma were below 1 in the first four quintiles of TCSE but above 1 in the highest quintile, 1.35 (95% CI 0.96 to 1.90). The OR increased with increasing TCSE 7+ years before diagnosis (p-trend 0.01; OR 1.91, 95% CI 1.05 to 3.47 in the highest quintile). A complementary analysis in which 44 glioma and 135 meningioma cases in the most exposed area of the brain were compared with gliomas and meningiomas located elsewhere in the brain showed increased ORs for tumours in the most exposed part of the brain in those with 10+ years of mobile phone use (OR 2.80, 95% CI 1.13 to 6.94 for glioma). Patterns for meningioma were similar, but ORs were lower, many below 1.0.

Conclusions: There were suggestions of an increased risk of glioma in long-term mobile phone users with high RF exposure and of similar, but apparently much smaller, increases in meningioma risk. The uncertainty of these results requires that they be replicated before a causal interpretation can be made.

Figure AI

Spatial deposition of radio frequency (RF) energy in the Gridmaster cells—the light cubes identify the most exposed region of the brain, that is, that with the highest specific absorption rate of RF energy from mobile phones. The dark cubes identify the less exposed area of the brain. The most exposed area (light cubes) correspond to about 16% of the brain volume and absorbs >50% of the total RF energy in the brain from mobile phones used at the ear.

Figure AII

Distribution of glioma cases and controls by level of total cumulative specific energy (TCSE) (in joules per kilogram) at the estimated centre of the tumour; centre is taken to be as estimated by neuroradiologist, where available, and as estimated by computer algorithm otherwise.