Assessment of extremely low frequency magnetic field exposure from GSM mobile phones

Abstract

Although radio frequency (RF) electromagnetic fields emitted by mobile phones have received much attention, relatively little is known about the extremely low frequency (ELF) magnetic fields emitted by phones. This paper summarises ELF magnetic flux density measurements on global system for mobile communications (GSM) mobile phones, conducted as part of the MOBI-KIDS epidemiological study. The main challenge is to identify a small number of generic phone models that can be used to classify the ELF exposure for the different phones reported in the study. Two-dimensional magnetic flux density measurements were performed on 47 GSM mobile phones at a distance of 25 mm. Maximum resultant magnetic flux density values at 217 Hz had a geometric mean of 221 (+198/-104) nT. Taking into account harmonic data, measurements suggest that mobile phones could make a substantial contribution to ELF exposure in the general population. The maximum values and easily available variables were poorly correlated. However, three groups could be defined on the basis of field pattern indicating that manufacturers and shapes of mobile phones may be the important parameters linked to the spatial characteristics of the magnetic field, and the categorization of ELF magnetic field exposure for GSM phones in the MOBI-KIDS study may be achievable on the basis of a small number of representative phones. Such categorization would result in a twofold exposure gradient between high and low exposure based on type of phone used, although there was overlap in the grouping.

Increasing Rates of Brain Tumours in the Swedish National Inpatient Register and the Causes of Death Register

“…The anatomical distribution to the human body of RF emissions depends on e.g., if the wireless phone is handheld or not, type of tissue and age [ 2 , 3 , 4 ]. The user may also be exposed to extremely low frequency (ELF)-EMF from the battery [ 5 , 6 ].…”

Mapping of static magnetic fields near the surface of mobile phones

“…We suggest special emphasis should be put into (1) inhomogeneous SMF (with a detailed characterization of both, intensities and gradients), and (2) combination of SMF (homogeneous and inhomogeneous) with RF EMF, with a fine sweeping of the parameters within the range of typical exposures (in opposition to testing single combinations). In even more complicated experiments, ELF EMF should also be considered 12 since their relationship with SMF have been long known 53 . Lastly it is worth mentioning that substantial reduction of the SMF from MP could be accomplished by replacing the standard electrodynamic loudspeakers and microphones (which include a permanent magnet) by their capacitive counterparts (which do not).…”

“…Due to all this concern and controversy, it is crucial to exhaustively know the fields MP users are exposed to. Naturally, most of the attention has been laid on the RF part of the spectrum, but also some on the extremely low frequency (ELF) range 12 – 15 . In contrast, static magnetic fields (SMF) from MP have been studied remarkably less 14 , 16 , in spite of the fact there is a wealth of evidence demonstrating SMF capability of eliciting biological effects (e.g., on genotoxicity, proliferation of both normal and cancerous cells, modulation of reactive oxygen species, enzymatic activity, stem cell proliferation and fate, repair of DNA lesions, and gene expression) 17 – 23 .…”

The MOBI-Kids Study Protocol: Challenges in Assessing Childhood and Adolescent Exposure to Electromagnetic Fields from Wireless Telecommunication Technologies and Possible Association with Brain Tumor Risk

“…Therefore, considerable effort was invested in developing the questionnaire’s exposure sections based on an extensive ELF and RF-EMF measurement and modeling campaign (26) and experience gained from INTERPHONE and expert opinions. Much thought was given to minimizing recall biases (e.g., use of prompts and a searchable mobile phone database to facilitate identification of phones used; first asking questions about present use and then previous use).…”