No effects of short-term exposure to mobile phone electromagnetic fields on human cognitive performance: A meta-analysis

ArticleinBioelectromagnetics 33(2) · February 2012with8 Reads
DOI: 10.1002/bem.20697 · Source: PubMed
Abstract
During recent years, a large number of studies on the effects of electromagnetic fields emitted by cellular mobile phones on human cognitive performance have been carried out. However, the results have been ambiguous. We carried out the current meta-analysis in order to investigate the impact of electromagnetic fields emitted by mobile phones on human cognition. Seventeen studies were included in the meta-analysis as they fulfill several requirements such as single- or double-blind experimental study design, and documentation of means and standard deviations of dependent variables. The meta-analysis was carried out as a group comparison between exposed and non-exposed subjects. No significant effects of electromagnetic fields emitted by Global System for Mobile Communications (GSM) and Universal Mobile Telecommunications System (UMTS) mobile phones were found. Cognitive abilities seem to be neither impaired nor facilitated. Results of the meta-analysis suggest that a substantial short-term impact of high frequency electromagnetic fields emitted by mobile phones on cognitive performance can essentially be ruled out. Bioelectromagnetics. © 2011 Wiley-Liss, Inc.

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    • "In the noiseless context, the Signal to Noise Ratio (SNR) is assumed to approach infinite: the measured values of magnetic field have been calculated by means of the MoM-based forward solver described in section 2. Different current source amplitudes have been tested: 0.1 mA, 1 mA, 5 mA, 25 mA and 50 mA. It has to be underlined that all these current values as well as the selected frequency, can be well tolerated by the human tissues also depending on the time of application (i.e. a few seconds) [10, 11, 17, 19]. On the other hand, the VHF waves are non ionizing ones with respect to the commonly used X-ray. "
    [Show abstract] [Hide abstract] ABSTRACT: Imaging techniques give a fundamental support to medical diagnostics during the pathology discovery as well as for the characterization of bio-medical structures. The imaging methods involve electromagnetic waves in a frequency range that spans from some Hz to GHz and over. Most of these methods involves ionizing waves and scanning of wide human body area even if only a focused inspection is needed. In this paper, a numerical method to evaluate the shape of microstructures for application in the medical field, with a very low invasiveness for the human body, is proposed. In particular, the tooth’s root canal is considered. In fact, this is one of the hot topic in the endodontic procedures where rotary instruments are widely used. These instruments are subjected to sudden mechanical damage during the surgical process, due to cyclic fatigue directly related to the canal geometrical characteristics. In order to develop improved endodontic procedure so that instrument breakage probability and canal milling precision are optimized, preliminary canal root reconstruction techniques have to be implemented. These techniques are usually based on invasive X-ray imaging. Thus, a low invasive, easy to use imaging technique that can be applied many times on the patient is of great interest. To this aim, a method based on a flexible thinwire antenna radiating non ionizing VHF waves, is proposed. By measuring the spatial magnetic field distribution in the neighboring, it is possible to reconstruct the microstructures image by estimating the shape of the antenna against a sensors panel. The mathematical model is strictly non-linear and the inverse problem described above is solved numerically; first simulation results are presented in order to show the validity and the robustness of the proposed approach.
    Full-text · Article · Jul 2013
    • "In addition, increasing blood flow in the brain induced by thermal effects of EMF continues to be debated with positive [40,41] or negative effects [42,43] . Furthermore, meta-analyses of human experimental studies show that EMFs emitted by mobile phones have a small impact on human attention and working memory [44], but no effect on human cognitive performance [45] or cognitive and psychomotor function [46]. An epidemiological study showed a relationship between exposure and health outcome and did not necessarily consider the usually long causal chain and molecular or biological mechanisms in the pathway from exposure to health outcome [47]. "
    [Show abstract] [Hide abstract] ABSTRACT: Concerns have developed for the possible negative health effects of radiofrequency electromagnetic field (RF-EMF) exposure to children's brains. The purpose of this longitudinal study was to investigate the association between mobile phone use and symptoms of Attention Deficit Hyperactivity Disorder (ADHD) considering the modifying effect of lead exposure. A total of 2,422 children at 27 elementary schools in 10 Korean cities were examined and followed up 2 years later. Parents or guardians were administered a questionnaire including the Korean version of the ADHD rating scale and questions about mobile phone use, as well as socio-demographic factors. The ADHD symptom risk for mobile phone use was estimated at two time points using logistic regression and combined over 2 years using the generalized estimating equation model with repeatedly measured variables of mobile phone use, blood lead, and ADHD symptoms, adjusted for covariates. The ADHD symptom risk associated with mobile phone use for voice calls but the association was limited to children exposed to relatively high lead. The results suggest that simultaneous exposure to lead and RF from mobile phone use was associated with increased ADHD symptom risk, although possible reverse causality could not be ruled out.
    Full-text · Article · Mar 2013
    • "Exposure to radiofrequency electromagnetic field is associated with overproduction of reactive oxygen species in the brain of rat.[18] Barth et al. reported that the cognitive abilities neither impaired nor facilitated electromagnetic fields emitted by GSM and Universal Mobile.[19] Neither heating nor overproduction of reactive oxygen species explain the cardiac effect of mobile in this study because the subjects were exposed to short duration of electromagnetic energy (40 sec). "
    [Show abstract] [Hide abstract] ABSTRACT: Electromagnetic energy radiated from mobile phones did not show significant effect on the blood pressure, heart rate, and electrocardiographic (ECG) parameters in animals and humans. This study aimed to investigate the effect of radiofrequency of mobile phone on the electrocardiographic parameters in patients with history of ischemic heart disease, taking into consideration the gender factor. A total number of 356 participants (129 males and 227 females) were admitted in this study. They were grouped into: subjects without cardiac diseases (Group I), patients with ischemic heart disease (Group II), and patients with history of cardiac diseases not related to myocardial ischemia (Group III). Electrocardiogram was obtained from each patient when the mobile phone was placed at the belt level and over precordium in turn-off mode (baseline) and turn-on mode for 40 sec ringing. The records of ECG were electronically analyzed. Prolongation of QTc interval was significantly observed in male gender of Groups I and III (P < 0.001). Male patients of Group II showed significant QTc interval prolongation (P = 0.01) and changes in the voltage criteria (P = 0.001). These changes were not observed in female patients with ischemic heart disease. The position of mobile at the belt level or over the precordium showed effects on the heart. The radiofrequency of cell phone prolongs the QT interval in human beings and it interferes with voltage criteria of ECG records in male patients with myocardial ischemia.
    Article · Jul 2012
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