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So far, human experimental research has failed to yield consistent evidence of an effect of RF on humans at permitted exposure levels.  This has lead many to conclude that effects are either non-existent or too weak to detect.  However, at least two issues have not been adequately addressed by the research so far.

The first, as highlighted in numerous technical reviews, stems from the use of only healthy young adults in most human studies.  Hence, the effect of RF on other populations that might be more susceptible to stressors (such as youths the elderly or self-reported hypersensitives) cannot be commented upon.

The second and related issue is that research has been based on the assessment of group averages, which assumes that RF bioeffects are similar for everyone and are therefore detectable as differences in group averages. However, if responses to RF are different for different people then bioeffects will be masked, and so we are conducting research to determine whether there are any consistent effects of RF within individuals.

 

 

Current Projects

 

Sensitivity of different age groups to RF Bioeffects Pilot Study

 

Project leader: A/Prof. Rodney Croft

 

NHMRC funded research staff: Ms. Jessica Dyson, Mr. Barry O’Neill, Ms. Sumie Leung, Ms. Denise Hamblin

 

Aims: This study will determine whether there are RF-effects that are expressed differently in different age-groups.  We will test the effect of RF  on several measures (heart rate, blood pressure, resting electroencephelogram (EEG), event related potentials (ERP's), cognition, and subjective symptoms) on three groups (youths, young adults, and older adults). 

 

MethodsA double blind, counterbalanced, crossover design was employed where 24 young adults attended two sessions 1 week apart. In both sessions, participants performed auditory oddball tasks, visual “n-back” working memory tasks, and resting tasks while electroencephalogram (EEG), heart rate, galvanic skin response, and respiration was recorded.  A mobile phone was mounted over the temporal region during these recordings, and set to active one week and inactive for the other week.  When active, the MP transmitted for 90 min using a continuous 902 MHz electromagnetic signal, with a mean power output of 250mW and a peak power output of 2W.

 

Results: Expected in 2006

 

 

Sensitivity of different age groups to Radiofrequency Bioeffects

 

Project leader: A/Prof. Rodney Croft

 

NHMRC funded research staff: Ms. Jessica Dyson, Mr. Barry O’Neill, Ms. Sumie Leung.

 

Aims: To test the effect of RF on several measures (heart rate, blood pressure, resting EEG, ERP, cognition, and subjective symptoms) as a function of age-group (youths, young adults, and older adults; n= 24 per group). 

 

Methods

This project will use an identical protocol to the previous study except that:

·        Participants will be tested under three conditions: during exposure to a 2G phone signal, a 3G phone signal, and sham conditions.  One condition will be administered per week according to a double-blind, counterbalanced, cross-over design.   

·        This study will not use alternate forms, as those used in the pilot study were not statistically validated and were therefore likely to introduce rather than remove error variance due to practice effects. 

·        Participants would complete a single auditory oddball task, the difficulty of which would be chosen through baseline testing.

·        The battery will be shortened to make the experiment more tolerable for participants. 

·        The cradle used to hold the mobile phone next to the participant’s head will be redesigned to be more comfortable.

·        Auditory stimuli will be delivered via computer speakers rather than foam ear phones inserted into the ear canal.  This will remove between-session variability in the sound pressure level of auditory stimuli due to variation in insertion depth of the ear phones. 

 

Results: Expected in 2007

 

Radiofrequency Hypersensitivity

 

Project leader: A/Prof. Rodney Croft

 

NHMRC funded research staff: Ms. Jessica Dyson, Mr. Barry O’Neill, Ms. Sumie Leung.

 

Aims: To scientifically validate the RF-bioeffects reported by self-reported ‘hypersensitives’.  To see whether (i) “hypersensitive” participants can accurately identify when the mobile phone is turned on (ii) experience more subjective effects than control subjects and (iii) experience more numerous or more severe subjective effects when the mobile phone is turned on than when it is turned off (sham exposed)

 

Methods Self-reported “hypersensitives” and non-sensitive “control” participants will attend two sessions, a week apart.  In both sessions, a mobile phone will be placed over the left temporal region while several measures are obtained (heart rate, blood pressure, resting EEG, ERP, cognition, and subjective symptoms).  For each participant, the phone will be set to emit an RF field one week (895 MHz, average power 250 mW, pulse modulated at 217 Hz, average SAR 0.11 W/kg) and will not emit a signal the other week (i.e. “sham” exposure).  Exposure conditions will be administered according to a double-blind, fully counterbalanced cross-over design. 

 

 

Results: Expected in 2007

 

Consistency of RF effects - Sleep

 

Project leader: A/Prof. Rodney Croft

 

NHMRC funded research staff: Ms Sarah Loughran (PhD candidate, Swinburne University)

 

Background: The ACRBR have previously reported a possible delay in melatonin production, decreased rapid eye movement sleep latency and increased electroencephalogram spectral power in 11.5-12.25 Hz frequency range in the initial part of sleep following exposure to mobile phone emissions for 30 mins (0.25 W average power) prior to going to bed in adult human volunteers (n = 55 for melatonin measurements; n = 50 for EEG measurements).  Examination of individual responses is suggestive of a small group of “responders.” 

 

Aim: to see whether the responses shown within individual participants from this first study could be reproduced.   

 

Methods Participants from the first study will be invited for retesting to determine whether they respond to RF in the same way as they did in the first study.  Specifically, we will attempt to recruit:10 “non-responders” (people who had no change in alpha due to RF), 10 “alpha-increasers” (people who had an increase in the alpha/sleep spindle range), and 10 “alpha-decreasers” (people who had a decrease in the alpha/sleep spindle range due to RF exposure).  This study will use a similar protocol to that used in the first study and will examine a variety of parameters relating to sleep EEG and melatonin production.

 

Results: Expected in 2007

 

Consistency of RF effects – Neural function in human volunteers.

 

Project leader: A/Prof. Rodney Croft

 

NHMRC funded research staff: Mr. Barry O'Neill (Research Assistant)

 

Background: Studies have failed to yield consistent evidence of RF-effects in human volunteers.  Reported effects have been infrequent, inconsistent in direction and difficult to replicate.  This has led many to conclude that effects are either non-existent or too subtle to detect.  However, previous research has been based on the assessment of group averages, in which opposing RF effects in different individuals may have cancelled out and resulting in a false null finding. 

Methods Measures will be obtained from a sample of healthy young adults and to group them according to RF response magnitude (stage 1). These ‘strong-’ and ‘non-’ responders would then be retested (stage 2) to determine whether the ‘strongs’ continue to exhibit a larger RF effect. Further, stage 2 testing will be more extensive, with subjects engaged in 7 mobile phone and 7 sham 20-min exposures (double-blind; order counterbalanced and randomly assigned). This will give extra information in that there will be

 

Results: Expected in 2007

 

The effect of caffeine vs. RF on neural function in human volunteers

 

Project leader: A/Prof. Rodney Croft

 

NHMRC funded research staff: Mr. Barry O'Neill (Research Assistant), Lorraine Valladares (Masters student RMIT)

 

 

Background: Caffeine is the most widely consumed behaviourally active substance in the world. The diuretic, respiratory, cardiovascular and central stimulant properties of caffeine have been known for decades. Thus in addition to societal use in beverages, caffeine has been used therapeutically to treat narcolepsy, asthma and apnoea, and as an analgesic adjunct. Due to its known effects on various physiological and neuropsychological measures, this study will use caffeine as a positive control in the examination of the bioeffects of RF.  

Aims: The present study has been designed as a positive control for the parallel study investigating the effects of  3rd generation (3G) technologies to allow a level of comparison between any resultant 3G effects and the effects of a common metric (caffeine consumption) on the same protocol employed to test for these 3G effects. 

Methods

This study will employ a placebo controlled, double-blind, fully counterbalanced and repeated measures design, ensuring that neither the participant nor primary investigator will be aware of the order of experimental condition over the two testing sessions. 

On testing days each participant would have a range of electrophysiological measures recorded while they engaged in a battery of sensory/cognitive tasks, after having consumed either caffeine or placebo condition (with 1 week between these two conditions).

 

Results: Expected in 2007

 

ELF modulated RF radiation influence on human central nervous system

 

 

Project leader:

Prof Irena Cosic, Dr Dean Cvetkovic

 

NHMRC funded research staff: Nicholas Perentos, Masters of Engineering candidate RMIT

 

 

Background: Mobile phone antennas emit extremely low frequency pulse modulated radiofrequency radiation, while their batteries emit extremely low frequency radiation.  It is unknown which of these components, if any, are able to affect the human brain and whether pulse modulation is necessary for RF to have an effect. 

 

Aims:  to examine and compare the effects of three different types of mobile phone radiation on the human central nervous system as indexed by electroencephalogram (EEG) and other physiological measurements.   

 

The radiations are:

1)      Extremely low frequency pulse modulated radio frequencies (ELF PM RF),

2)      Pure radio frequencies and

3)      Pulsed extremely low frequencies only.

 

Results: Expected in 2007

 

 

Influence of electromagnetic emissions from mobile phones on nervous function in the human brain and heart

 

 

Project leader: Howard D’Costa, PhD candidate

 

NHMRC funded research staff: Prof. Irena Cosic, Mr Ray McKenzie, Dr Vitas Anderson

 

 

Background: This research investigates the influence of mobile phone electromagnetic exposures on the nervous function in the human brain and heart. Pulsed continuous wave (CW) radiofrequency exposures are produced near to the human head using a model mobile phone during the simultaneous monitoring of brain wave activity and heart function.  Brain wave activity is measured by electroencephalograph (EEG) and heart function is measured by acquisition of the electrocardiograph (ECG) and a blood pressure comparative (PPG).  As far as possible methodologies employed are consistent with previous reported studies in order to allow assessment, and use standardised quantifiable metrics so that biological significance of the data can be meaningfully interpreted.  Thus far, the total projected number of 100 people have participated in the experimental stages of this study.   The outcomes of the project aim to address uncertainties in the present data that are of concern to national and international regulatory and health agencies.  The results of this investigation are due to be sent a reputable journal in the very near future. 

 

 

Results: Expected in 2007

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