This thesis aims to determine whether RF pulsed exposures from mobile phones can influence nervous function within the human brain and heart. In order to address this objective, a robust double-blind study to investigate mobile phone exposures on nervous response has been undertaken by means of analysis of electrophysiological test measures of brain wave activity and heart responses. Generally, test measurements of the electroencephalogram (EEG), the electrocardiogram (ECG), and the pulse plethysmogram (PPG) (for indications of blood pressure response) have been undertaken whilst participants are exposed and sham exposed to various GSM mobile phone radiofrequency and low-frequency protocols. In initial work, both standby and full-power mode GSM exposures have been investigated (Chapter 3 - EEG investigated only), while pulsed 900 MHz and 1800 MHz continuous wave exposures have been investigated in the final experimental work involving 100 test participants (Ch apter 8 - EEG, ECG, and PPG measures are investigated). Four predominant outcomes are determined from the final experimental work conducted. These main outcomes specifically include: 1. A new 'characteristic' finding in the EEG alpha band (8-13 Hz) as due to 900 MHz exposures is observed from almost all recording sites, over both brain hemispheres. Notably, this response only appears at 900 MHz, though is not observable for the 1800 MHz exposure; 2. An EEG effect due to both pulsed 900 MHz and 1800 MHz exposures notably appearing at 16 Hz is a new critical finding and is observed across both hemispheres. Most importantly, at this beta rhythm only a decreasing tendency in EEG power can be noted for the 900 MHz exposure tested but only an increasing tendency in EEG power may be noted at 1800 MHz, suggesting that the direction of the effect in EEG power may be dependent on the RF component; 3. Effects at 900 MHz on the contralateral side to exposure at central, temporal, and parietal sites appear to indicate a common median difference response between sham and exposure EEG spectral power density, which does not appear on the ipsilateral side to exposure; 4. As consistent with most previously published research, 900 MHz or 1800 MHz exposures pulsed at 217 Hz do not appear to alter heart rate, heart rate variability (HRV), or blood pressure variability (BPV). To reduce confounding factors and errors in experimental results, several novel approaches were developed as described (Chapters 4 - 8). These approaches include the development and testing of an experimental handset to support multiple mobile phone signals, a comparative analysis of 900 MHz and 1800 MHz exposures (near the health protection limits) on the same group of participants in simultaneous experiments, development of a statistical analysis approach to EEG that addresses both type 1 and type 11 errors at high resolution, and quantification of potential effects of EEG recording leads on SAR and electric field distribution (at both 900 MHz and 1800 MHz) inside a SAM phantom and realistic computational head model. Outcomes of this research address forefront international health concerns regarding almost 2-billion mobile phone users worldwide.
| Identifer | oai:union.ndltd.org:ADTP/235517 |
| Date | January 2009 |
| Creators | D'Costa, Howard Francis, n/a |
| Publisher | RMIT University. Electrical And Computer Engineering |
| Source Sets | Australiasian Digital Theses Program |
| Language | English |
| Detected Language | English |
| Rights | http://www.rmit.edu.au/help/disclaimer, Copyright Howard Francis D'Costa |
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