4G or the fourth generation of cellular technology is called Long Term Evolution or LTE. This technology employs new digital signal processing and modulation to increase the capacity and speed of wireless telecommunications networks.
The standard for LTE was finalized in December, 2008, and the first mobile phone to employ this technology was released in September, 2010. By the end of 2017, 41 countries supported LTE coverage over at least 75% of their land area. In North America, the number of LTE mobile devices in use, 365 million, now exceeds the size of the population.
LTE was launched without any pre-market safety testing. To date, I have found several peer-reviewed studies that examined the acute effects of exposure to LTE radiation on brain functioning and no research on human health effects.Thus, we do not know whether long-term exposure to LTE radiation is safe.
The latest study found diminished fertility in male rats exposed to a 4G (LTE) smartphone for 150 days (see below).
The fifth generation of cellular technology, or 5G, is currently being launched in selected areas in many countries. Although once again no pre-market safety testing was conducted, related research suggests various types of harm to humans and other species from exposure to 5G radiation.
The abstracts for 4G (LTE) studies appear below.
LTE was launched without any pre-market safety testing. To date, I have found several peer-reviewed studies that examined the acute effects of exposure to LTE radiation on brain functioning and no research on human health effects.Thus, we do not know whether long-term exposure to LTE radiation is safe.
The latest study found diminished fertility in male rats exposed to a 4G (LTE) smartphone for 150 days (see below).
The fifth generation of cellular technology, or 5G, is currently being launched in selected areas in many countries. Although once again no pre-market safety testing was conducted, related research suggests various types of harm to humans and other species from exposure to 5G radiation.
The abstracts for 4G (LTE) studies appear below.
Effects of mobile phone radiation on certain hematological parameters
Christopher B, Sheena MY, Uddin Khandaker M, Bradley DA, Chew MT, Jojo PJ. Effects of mobile phone radiation on certain hematological parameters. Radiation Physics and Chemistry. Published online September 14, 2019. 108443. https://doi.org/10.1016/j.radphyschem.2019.108443.
Highlights
• Mobile phone radiation affects blood hemoglobin level, white blood cell and platelets count and erythrocytes sedimentation rate.
• Effects of mobile phone radiation on hematological factors studied in a controlled condition in the laboratory.
• A matched case control approach was adopted for the investigation.
• Long time and over exposure to mobile phone radiation may affect the individual health.
Abstract
Exorbitant chronic exposure to any sort of radiation is hazardous to human health. Besides ionizing radiation, exposures to electromagnetic radiation mainly from the use of mobile phones have become a matter of great health concern, especially its extortionate use even by children. At the same time there are several myths related to the ill effects including carcinogenicity of the prolonged exposure continuously. The objective of this investigation was to find the effect on certain vital hematological parameters namely hemoglobin level, white blood cell (WBC) count, platelet count and erythrocytes sedimentation rate (ESR) level due to the prolonged exposure to mobile radiations through in vitro examination of human blood samples. Matched case control methodology was adopted for the study. Blood samples were collected by clinicians from 27 voluntary subjects for investigation. From each, one sample was kept un-exposed while the other three samples were exposed to mobile microwave radiations for 60 min continuously in identical and controlled conditions. A 4G hand phone of a very popular brand having transmission frequency range from 2.3 to 2.4 GHz including uplink and downlink was used. Hematological analyses were carried out on fresh samples immediately after collection. For comparison of the levels of hematological parameters, blood exposed to 1 h of phone radiation and control were analysed. Experimental results show that there is a significant change on the hematological components. The exposed blood samples were found to have decrease in platelet count only. Hemoglobin level, ESR rate and the WBC counts were found to be increased. While these observations are performed in a controlled laboratory conditions, the tremendous growth in number of mobile phone users, the effects could be many more folds especially in work places and cities even through passive exposure.
https://www.sciencedirect.com/science/article/abs/pii/S0969806X19305481
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Early-life exposure to pulsed LTE radiofrequency fields causes persistent changes in activity and behavior in mice
Broom KA, Findlay R, Addison DS, Goiceanu C, Sienkiewicz Z. Early-life exposure to pulsed LTE radiofrequency fields causes persistent changes in activity and behavior in C57BL/6 J mice. Bioelectromagnetics. 2019 Sep 15. doi: 10.1002/bem.22217.
Broom KA, Findlay R, Addison DS, Goiceanu C, Sienkiewicz Z. Early-life exposure to pulsed LTE radiofrequency fields causes persistent changes in activity and behavior in C57BL/6 J mice. Bioelectromagnetics. 2019 Sep 15. doi: 10.1002/bem.22217.
Abstract
Despite much research, gaps remain in knowledge about the potential health effects of exposure to radiofrequency (RF) fields. This study investigated the effects of early-life exposure to pulsed long term evolution (LTE) 1,846 MHz downlink signals on innate mouse behavior. Animals were exposed for 30 min/day, 5 days/week at a whole-body average specific energy absorption rate (SAR) of 0.5 or 1 W/kg from late pregnancy (gestation day 13.5) to weaning (postnatal day 21). A behavioral tracking system measured locomotor, drinking, and feeding behavior in the home cage from 12 to 28 weeks of age. The exposure caused significant effects on both appetitive behaviors and activity of offspring that depended on the SAR. Compared with sham-exposed controls, exposure at 0.5 W/kg significantly decreased drinking frequency (P ≤ 0.000) and significantly decreased distance moved (P ≤ 0.001). In contrast, exposure at 1 W/kg significantly increased drinking frequency (P ≤ 0.001) and significantly increased moving duration (P ≤ 0.005). In the absence of other plausible explanations, it is concluded that repeated exposure to low-level RF fields in early life may have a persistent and long-term effect on adult behavior.
Despite much research, gaps remain in knowledge about the potential health effects of exposure to radiofrequency (RF) fields. This study investigated the effects of early-life exposure to pulsed long term evolution (LTE) 1,846 MHz downlink signals on innate mouse behavior. Animals were exposed for 30 min/day, 5 days/week at a whole-body average specific energy absorption rate (SAR) of 0.5 or 1 W/kg from late pregnancy (gestation day 13.5) to weaning (postnatal day 21). A behavioral tracking system measured locomotor, drinking, and feeding behavior in the home cage from 12 to 28 weeks of age. The exposure caused significant effects on both appetitive behaviors and activity of offspring that depended on the SAR. Compared with sham-exposed controls, exposure at 0.5 W/kg significantly decreased drinking frequency (P ≤ 0.000) and significantly decreased distance moved (P ≤ 0.001). In contrast, exposure at 1 W/kg significantly increased drinking frequency (P ≤ 0.001) and significantly increased moving duration (P ≤ 0.005). In the absence of other plausible explanations, it is concluded that repeated exposure to low-level RF fields in early life may have a persistent and long-term effect on adult behavior.
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Long-term exposure to 4G smartphone radiation diminished male reproductive potential by directly disrupting Spock3-MMP2-BTB axis in the testes of adult rats
Yu G, Tang Z, Chen H, Chen Z, Wang L, Cao H, Wang G, Xing J, Shen H, Cheng Q, Li D, Wang G, Xiang Y, Guan Y, Zhu Y, Liu Z, Bai Z. Long-term exposure to 4G smartphone radiofrequency electromagnetic radiation diminished male reproductive potential by directly disrupting Spock3-MMP2-BTB axis in the testes of adult rats. Sci Total Environ. 2019 Aug 31;698:133860. doi: 10.1016/j.scitotenv.2019.133860.
Abstract
The correlation between long-term exposure to SRF-EMR and the decline in male fertility is gradually receiving increasing attention from the medical society. While male reproductive organs are often exposed to SRF-EMR, little is currently known about the direct effects of long-term SRF-EMR exposure on the testes and its involvement in the suppression of male reproductive potential. The present study was designed to investigate this issue by using 4G SRF-EMR in rats. A unique exposure model using a 4G smartphone achieved localized exposure to the scrotum of the rats for 6 h each day (the smartphone was kept on active talk mode and received an external call for 1 min over 10 min intervals). Results showed that SRF-EMR exposure for 150 days decreased sperm quality and pup weight, accompanied by testicular injury. However, these adverse effects were not evident in rats exposed to SRF-EMR for 50 days or 100 days. Sequencing analysis and western blotting suggested Spock3 overexpression in the testes of rats exposed to SRF-EMR for 150 days. Inhibition of Spock3 overexpression improved sperm quality decline and alleviated testicular injury and BTB disorder in the exposed rats. Additionally, SRF-EMR exposure suppressed MMP2 activity, while increasing the activity of the MMP14-Spock3 complexes and decreasing MMP14-MMP2 complexes; these results were reversed by Spock3 inhibition. Thus, long-term exposure to 4G SRF-EMR diminished male fertility by directly disrupting the Spock3-MMP2-BTB axis in the testes of adult rats. To our knowledge, this is the first study to show direct toxicity of SRF-EMR on the testes emerging after long-term exposure.
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Short-term radiofrequency exposure from new generation mobile phones reduces EEG alpha power with no effects on cognitive performance.
Vecsei Z, Knakker B, Juhász P, Thuróczy G, Trunk A, Hernádi I. Short-term radiofrequency exposure from new generation mobile phones reduces EEG alpha power with no effects on cognitive performance. Sci Rep. 2018 Dec 20;8(1):18010. doi: 10.1038/s41598-018-36353-9.
Abstract
Although mobile phone (MP) use has been steadily increasing in the last decades and similar positive trends are expected for the near future, systematic investigations on neurophysiological and cognitive effects caused by recently developed technological standards for MPs are scarcely available. Here, we investigated the effects of radiofrequency (RF) fields emitted by new-generation mobile technologies, specifically, Universal Mobile Telecommunications System (UMTS) and Long-Term Evolution (LTE), on intrinsic scalp EEG activity in the alpha band (8-12 Hz) and cognitive performance in the Stroop test. The study involved 60 healthy, young-adult university students (34 for UMTS and 26 for LTE) with double-blind administration of Real and Sham exposure in separate sessions. EEG was recorded before, during and after RF exposure, and Stroop performance was assessed before and after EEG recording. Both RF exposure types caused a notable decrease in the alpha power over the whole scalp that persisted even after the cessation of the exposure, whereas no effects were found on any aspects of performance in the Stroop test. The results imply that the brain networks underlying global alpha oscillations might require minor reconfiguration to adapt to the local biophysical changes caused by focal RF exposure mimicking MP use.
Open access paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301959/
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The Effect of a Single
30-Min Long Term Evolution Mobile Phone-Like Exposure on Thermal Pain
Threshold of Young Healthy Volunteers
Vecsei Z, Thuróczy G, Hernádi I. The Effect of a Single 30-Min Long Term Evolution Mobile Phone-Like Exposure on Thermal Pain Threshold of Young Healthy Volunteers. Int J Environ Res Public Health. 2018 Aug 27;15(9). pii: E1849. doi: 10.3390/ijerph15091849.
Abstract
Although the majority of mobile phone (MP) users do not attribute adverse effects on health or well-being to MP-emitted radiofrequency (RF) electromagnetic fields (EMFs), the exponential increase in the number of RF devices necessitates continuing research aimed at the objective investigation of such concerns. Here we investigated the effects of acute exposure from Long Term Evolution (LTE) MP EMFs on thermal pain threshold in healthy young adults. We use a protocol that was validated in a previous study in a capsaicin-induced hyperalgesia model and was also successfully used to show that exposure from an RF source mimicking a Universal Mobile Telecommunications System (UMTS) MP led to mildly stronger desensitization to repeated noxious thermal stimulation relative to the sham condition. Using the same experimental design, we did not find any effects of LTE exposure on thermal pain threshold. The present results, contrary to previous evidence obtained with the UMTS modulation, are likely to originate from placebo/nocebo effects and are unrelated to the brief acute LTE EMF exposure itself. The fact that this is dissimilar to our previous results on UMTS exposure implies that RF modulations might differentially affect pain perception and points to the necessity of further research on the topic.
Vecsei Z, Thuróczy G, Hernádi I. The Effect of a Single 30-Min Long Term Evolution Mobile Phone-Like Exposure on Thermal Pain Threshold of Young Healthy Volunteers. Int J Environ Res Public Health. 2018 Aug 27;15(9). pii: E1849. doi: 10.3390/ijerph15091849.
Abstract
Although the majority of mobile phone (MP) users do not attribute adverse effects on health or well-being to MP-emitted radiofrequency (RF) electromagnetic fields (EMFs), the exponential increase in the number of RF devices necessitates continuing research aimed at the objective investigation of such concerns. Here we investigated the effects of acute exposure from Long Term Evolution (LTE) MP EMFs on thermal pain threshold in healthy young adults. We use a protocol that was validated in a previous study in a capsaicin-induced hyperalgesia model and was also successfully used to show that exposure from an RF source mimicking a Universal Mobile Telecommunications System (UMTS) MP led to mildly stronger desensitization to repeated noxious thermal stimulation relative to the sham condition. Using the same experimental design, we did not find any effects of LTE exposure on thermal pain threshold. The present results, contrary to previous evidence obtained with the UMTS modulation, are likely to originate from placebo/nocebo effects and are unrelated to the brief acute LTE EMF exposure itself. The fact that this is dissimilar to our previous results on UMTS exposure implies that RF modulations might differentially affect pain perception and points to the necessity of further research on the topic.
Open access paper: http://www.mdpi.com/1660-4601/
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Modulation of brain functional connectivity by exposure to LTE (4G) cell phone radiation
Wei Y, Yang J, Chen Z, Wu T, Lv B. Modulation of resting‐state brain
functional connectivity by exposure to acute fourth‐generation long‐term
evolution electromagnetic field: An fMRI study. Bioelectromagnetics.
Published online 18 December 2018.
Abstract
By now, the neurophysiological effect of electromagnetic field (EMF)
exposure and its underlying regulating mechanisms are not well
manifested. In this study, we aimed to investigate whether acute
long‐term evolution (LTE) EMF exposure could modulate brain functional
connectivity using regional homogeneity (ReHo) method and seed‐based
analysis on resting‐state functional magnetic resonance imaging (fMRI).
We performed the LTE‐EMF exposure experiment and acquired the
resting‐state brain activities before and after EMF exposure. Then we
applied ReHo index to characterize the localized functional connectivity
and seed‐based method to evaluate the inter‐regional functional
connectivity. Statistical comparisons were conducted to identify the
possible evidence of brain functional connectivity modulation induced by
the acute LTE‐EMF exposure. We found that the acute LTE‐EMF exposure
modulated localized intra‐regional connectivity (p < 0.05, AlphaSim
corrected, voxel size ≥ 18) and inter‐regional connectivity in some
brain regions (p < 0.05, AlphaSim corrected, voxel size ≥ 18). Our
results may indicate that the approaches relying on network‐level
inferences could provide deeper insight into the acute effect on human
functional activity induced by LTE‐EMF exposure.
Excerpts
"Currently, multiple standards exist for wireless communication, which ranges from second‐generation (2G, GSM) to third‐generation (3G, UMTS) and fourth‐generation (4G, LTE) networks in daily life. Fifth‐generation (5G) networks will start to appear as a commercial infrastructure in the near future. Although we enjoy the convenience of mobile phones, the widespread use of them has raised attention about the possible health effects of radiofrequency (RF) electromagnetic field (EMF) exposure [ICNIRP, 1998].
With neuroimaging and neuropsychology tools, the effect of EMF on the human brain can be reflected as signals of electrical activity [Hamblin et al., 2006; Croft et al., 2010; Lustenberger et al., 2013; Roggeveen et al., 2015a, b], cortical excitability [Tombini et al., 2013], cerebral blood flow [Aalto et al., 2006], brain glucose metabolism [Volkow et al., 2011], and hemodynamic responses [Volkow et al., 2011; Curcio et al., 2012]. Previous studies reported that GSM signals modulated alpha band power in resting‐state electroencephalogram (EEG) [Croft et al., 2010] or some event‐related potential (ERP) components during cognitive tasks [Hamblin et al., 2006], whereas other studies did not detect any GSM exposure‐induced changes in brain activity [Curcio et al., 2012]. Although some studies showed no significant effects of 3G signals on any neurophysiological measurements [Zhang et al., 2017], recent EEG studies reported significant EEG alterations associated with 3G mobile phone radiation [Roggeveen et al., 2015a, b]. The inconsistency could partly be attributed to different exposure frequencies, modulation modes, and exposure durations [Zhang et al., 2017]. For 4G‐related signals, only our two previous studies have investigated the acute effect of long‐term evolution (LTE) EMF exposure on human brain function [Lv et al., 2014; Yang et al., 2016] using EEG and functional magnetic resonance imaging (fMRI). We found that 30 min of LTE‐EMF exposure modulated the alpha/beta EEG bands [Yang et al., 2016] and spontaneous low‐frequency fluctuations [Lv et al., 2014] in some brain regions. Since LTE networks have been widely deployed, we should make more effort to evaluate the possible effects of LTE‐EMF exposure from different perspectives."
"In this study, we aimed to investigate whether acute LTE‐EMF exposure could modulate brain functional connectivity using resting‐state fMRI. We performed LTE‐EMF exposure experiments lasting for 30 min under a controllable environment and recorded the resting‐state brain activities before and after EMF exposure. Then, we applied the regional homogeneity (ReHo) index [Zang et al., 2004] to characterize localized intraregional connectivity and the seed‐based functional connectivity method [Margulies et al., 2010] to evaluate interregional brain connectivity. Statistical comparisons were conducted to identify possible evidence of brain functional connectivity modulation induced by acute LTE‐EMF exposure."
"Although the SAR values by LTE‐EMF exposure indicated no obvious temperature increase during the exposure experiments and the brain was excellent in terms of thermal regulation, we could not preclude that thermal changes, even minute changes, could be responsible for the instantaneous changes in neural firing. SAR is a metric averaging over 6 min, and its applicability for neurological studies should be discussed."
“To eliminate study biases, we employed a double‐blind, crossover,
randomized, and counterbalanced design. Each participant underwent two
experimental sessions including real exposure and sham exposure, which
were separated by 1 day….The time‐division LTE signal (2.573 GHz) was
produced by a signal generator a
standard formulation for LTE signals….The power delivered to the
standard dipole of 2.6 GHz was 24
dBm (mean value), which was equivalent to a theoretical maximal emission
by an LTE terminal. The experiments were conducted in a shielding room
to avoid the influence of environmental EMF. Each exposure session
lasted for 30 min.”
“Numerical simulations that yielded spatial peak SAR averaging over 10 g
tissues for the subjects was 0.98 ± 0.27 W/kg, with a maximal value of
1.52 W/kg, which was below the safety limits [ICNIRP, 1998].”
“In our previous studies, we found that LTE‐EMF exposure depressed the
amplitude of spontaneous low frequency fluctuations (ALFFs) in some
brain regions [Lv et al., 2014], such as those surrounding the left
superior temporal gyrus and middle temporal gyrus (STG_L and MTG_L),
right superior temporal gyrus (STG_R), right medial frontal gyrus, and
right paracentral lobule (MFG_R and PCL_R). In the present study, we
found new evidence that acute LTE‐EMF exposures lasting for 30 min
modulated brain functional connectivity including not only localized
intraregional connectivity, but also interregional connectivity.”
Conclusion
"Our results may indicate that approaches relying on network‐level inferences can provide deeper insights into the acute effects of LTE‐EMF exposure with intensities below the current safety limits on human functional connectivity. In the future, we need to investigate the evolution of the effect over time.”
May 2, 2016
By the end of 2013, 100 million cell phones in the U.S. operated on LTE. This number worldwide is expected to exceed 1 billion by the end of this year.
Following is a summary of the second study published on the effects of 4th generation LTE cell phone radiation on the brain activity of cell phone users by the China Academy of Telecommunication Research of the Ministry of Industry and Information Technology.
The original study showed that 30 minutes of exposure to LTE phone radiation affected brain activity in the left superior temporal gyrus, left middle temporal gyrus, right superior temporal gyrus, right medial frontal gyrus and right paracentral lobule. The current study found that a 30-minute exposure to LTE radiation modulated the EEG in the alpha and beta bands at the frontal region of the near and remote sides, and at the temporal region on the near side.
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Yang L, Chen Q, Lv B, Wu T. Long-Term Evolution Electromagnetic Fields Exposure Modulates the Resting State EEG on Alpha and Beta Bands. Clin EEG Neurosci. 2017 May;48(3):168-175. doi: 10.1177/1550059416644887.
Abstract
Long-term evolution (LTE) wireless telecommunication systems are widely used globally, which has raised a concern that exposure to electromagnetic fields (EMF) emitted from LTE devices can change human neural function. To date, few studies have been conducted on the effect of exposure to LTE EMF. Here, we evaluated the changes in electroencephalogram (EEG) due to LTE EMF exposure. An LTE EMF exposure system with a stable power emission, which was equivalent to the maximum emission from an LTE mobile phone, was used to radiate the subjects. Numerical simulations were conducted to ensure that the specific absorption rate in the subject's head was below the safety limits. Exposure to LTE EMF reduced the spectral power and the interhemispheric coherence in the alpha and beta bands of the frontal and temporal brain regions. No significant change was observed in the spectral power and the inter-hemispheric coherence in different timeslots during and after the exposure. These findings also corroborated those of our previous study using functional magnetic resonant imaging.
http://1.usa.gov/2475GM3
Long-Term Evolution EMF Exposure Modulates Resting State EEG on Alpha and Beta Bands
Yang L, Chen Q, Lv B, Wu T. Long-Term Evolution Electromagnetic Fields Exposure Modulates the Resting State EEG on Alpha and Beta Bands. Clin EEG Neurosci. 2017 May;48(3):168-175. doi: 10.1177/1550059416644887.
Abstract
Long-term evolution (LTE) wireless telecommunication systems are widely used globally, which has raised a concern that exposure to electromagnetic fields (EMF) emitted from LTE devices can change human neural function. To date, few studies have been conducted on the effect of exposure to LTE EMF. Here, we evaluated the changes in electroencephalogram (EEG) due to LTE EMF exposure. An LTE EMF exposure system with a stable power emission, which was equivalent to the maximum emission from an LTE mobile phone, was used to radiate the subjects. Numerical simulations were conducted to ensure that the specific absorption rate in the subject's head was below the safety limits. Exposure to LTE EMF reduced the spectral power and the interhemispheric coherence in the alpha and beta bands of the frontal and temporal brain regions. No significant change was observed in the spectral power and the inter-hemispheric coherence in different timeslots during and after the exposure. These findings also corroborated those of our previous study using functional magnetic resonant imaging.
http://1.usa.gov/2475GM3
Excerpts
".. the results of resting state EEG experiments have been contradictory. For example, some studies have reported enhancement of the alpha (8-12 Hz) and beta (13-30 Hz) band power values after exposure to pulse-modulated 450- and 900-MHz signals, pulse-modulated magnetic fields, and active mobile phone signals. In contrast, some studies have shown decreased alpha band activity after 20 minutes of extremely low-frequency EMF exposure, or 5 minutes of magnetic field exposure, or global system for mobile communications (GSM) EMF exposure. Many studies also found no changes in the EEG after either modulated or unmodulated EMF exposure. These inconsistencies could be attributed not only to the differences in the signal type, the modulation, the exposure frequency, the exposure intensity individual anatomy, the ages of the subjects, and the exposure duration but also to the lack of rigorous experimental designs. Most of the previously published studies have focused on GSM, WiFi, and Universal Mobile Telecommunications System (UMTS), signals. An emerging technology, “long term evolution” (LTE) wireless service, has been deployed since 2009 and the number of global LTE subscribers is expected to reach 1.37 billion by the end of 2015. Other than our previous functional magnetic resonance imaging (fMRI) study, there are very few reports on the effect of exposure to LTE EMF on brain function. We previously found that 30 minutes of exposure to LTE EMF modulated the spontaneous low-frequency fluctuations. We were interested in confirming our previous results using another neurophysiological method and also sought to assess the evolution of the effect over time during such exposure. In this article, we have investigated for the first time the changes in the resting state EEG caused by exposure to LTE signals. The exposure dose was below the current safety limit. In order to assess brain activities on different levels, we evaluated spectral power and interhemispheric coherence, which allowed investigation of EEG changes in specific brain regions, as well as their correlations, at different time points. We show that exposure to LTE EMF decreased the alpha and beta band power spectrum and interhemisphere coherence."
"The age of the subjects was 30.2 ± 2.7 years."
"A plastic spacer of 1 cm was used to maintain the distance between the right ear and a standard dipole. We applied 2 power meters to ensure a constant incident power to the emission dipole. The power delivered to the dipole was 24 dBm (peak value), equivalent to a theoretical maximum emission by an LTE terminal."
"All 25 subjects participated in the double-blind and counterbalanced experiment."
"The experiment included 2 sessions, which were separated by 1 week. Each session lasted 50 minutes and comprised 5 time slots. We indicated each time slot (10 minutes) in a session as sub1 to sub5. The radiation dipole was power off for the first (preexposure, sub1) and the last 10 minutes (postexposure, sub5) timeslots. Subjects were exposed to real EMF exposure in the 3 time slots (sub2 to sub4) between the first and the last 10 minutes in only 1 of the 2 sessions. The order of the 2 sessions was randomly selected per subject. The subjects were not informed of the sequence of each session; however, they were aware of the possibility of being exposed. On the other hand, the staff who analyzed the data did not know the sources of the EEG traces."
"The simulations yielded 1.34 W/kg (pSAR10g) and 1.96 W/kg (pSAR1g), with the electrodes, and 1.27 W/kg (pSAR10g) and 1.78 W/kg (pSAR1g), without the electrodes (Figure 2) when the dipole emitted radiation. Therefore, the presence of the EEG electrodes increased pSAR10g and pSAR1g by about 5.5% and 10.1%, respectively. Accordingly, the maximum resultant temperature increase was no more than 0.1°C ...."
"Previous studies on GSM and UMTS signal exposure frequently reported changes in interhemispheric coherence and the spectral power in the alpha band in the frontal and temporal regions, which were also confirmed by our results on LTE EMF exposure. Moreover, modulation of the power spectrum in the beta band, including both an increase and a decrease, was reported. Several reasons may account for the inconsistency. First, the signal frequency and its modulation influenced the affected EEG band: for example, exposure to 2G signals affect the alpha rhythms, whilst exposure to 3G signals do not. In contrast, the modulated 450-MHz signals of various intensities can change beta activity much more markedly than alpha band power. Second, gender and the individual sensitivity 38,40 may influence the effect on different bands. Hence, we attempted to reduce the variability by enrolling the subjects with the same gender and age."
"In particular, power spectral analysis has shown significant differences in the left frontal brain regions, that is, the remote side, on exposure. This may be associated with modulation of neural activity in the remote/contralateral brain regions. The remote effects of EMF have been observed in many previous studies. Our results reconfirmed that the effects were also seen with LTE EMF exposure."
"The power spectrum and the interhemispheric coherence did not differ significantly over sub2 to sub5. Thus, the observed effect did not change with the exposure time and the effect was therefore not developing. The reduction in alpha band activity has been associated with a decrease in individual information-processing ability, alertness, and cognitive performance. The decrease in beta band activity could be interpreted as decreased alertness, arousal, and excitement or a low level of fatigue. Notably, EEG power fluctuation was not in one-one correspondence with the change in behavioral/cognitive performance which should be evaluated by specifically designed experiments as the report by Haarala et al. No conclusion could be obtained by our study that the present EMF exposure affected the subjects’ cognitive abilities."
"This work studied EEG changes caused by LTE EMF exposure. An exposure system with a fixed power incident to a radiation dipole was used; this simulation demonstrated that the SAR was within the safety limits. LTE EMF exposure modulated the EEG in the alpha and beta bands at the frontal region of the near and remote sides, and at the temporal region on the near side. No developing effect was found in the periods during and after the exposure. Our results agreed to some extent with those of our previous fMRI study on LTE exposure. Our finding indicated that the LTE EMF exposure with the intensity beneath the safety limits could modulate the brain activities."
"Future studies should focus on the correlation of EEG changes with spatial SAR distribution. By taking individual anatomical structure into consideration, a precise dose-effect relationship can be established. EEG changes with a finer temporal resolution during the exposure session should also be evaluated."
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The alteration of spontaneous low frequency oscillations caused by acute electromagnetic fields exposure
Lv B, Chen Z, Wu T, et al. The alteration of spontaneous low frequency oscillations caused by acute electromagnetic fields exposure. Clin Neurophysiol. 2014;125:277-286.
Abstract
OBJECTIVE: The motivation of this study is to evaluate the possible alteration of regional resting state brain activity induced by the acute radiofrequency electromagnetic field (RF-EMF) exposure (30 minutes) of Long Term Evolution (LTE) signal.
METHODS: We designed a controllable near-field LTE RF-EMF exposure environment. Eighteen subjects participated in a double-blind, crossover, randomized and counterbalanced experiment including two sessions (real and sham exposure). The radiation source was close to the right ear. Then the resting state fMRI signals of human brain were collected before and after the exposure in both sessions. We measured the amplitude of low frequency fluctuation (ALFF) and fractional ALFF (fALFF) to characterize the spontaneous brain activity.
RESULTS: We found the decreased ALFF value around in left superior temporal gyrus, left middle temporal gyrus, right superior temporal gyrus, right medial frontal gyrus and right paracentral lobule after the real exposure. And the decreased fALFF value was also detected in right medial frontal gyrus and right paracentral lobule.
CONCLUSIONS: The study provided the evidences that 30 minute LTE RF-EMF exposure modulated the spontaneous low frequency fluctuations in some brain regions.
SIGNIFICANCE: With resting state fMRI, we found the alteration of spontaneous low frequency fluctuations induced by the acute LTE RF-EMF exposure.
http://1.usa.gov/1gTqxVr
