Thursday, December 3, 2020

Recent Research on Wireless Radiation and Electromagnetic Fields

I have been circulating abstracts of newly-published scientific papers on wireless radiation and electromagnetic fields (EMF) about once or twice a month since August 2016. These updates are sent to several hundred EMF scientists around the world.

The latest additions appear below.

The complete collection of abstracts now covers more than 1,000 scientific papers. This 770-page document (pdf) can be downloaded by clicking on the following link:


Note: This link will change when new abstracts are added to the collection.

Recent Papers

Cellular Phone Use and Risk of Tumors: Systematic Review and Meta-Analysis

Yoon-Jung Choi+, Joel M. Moskowitz+, Seung-Kwon Myung, Yi-Ryoung Lee, Yun-Chul Hong. Cellular Phone Use and Risk of Tumors: Systematic Review and Meta-Analysis. International Journal of Environmental Research and Public Health. 2020, 17(21), 8079; https://doi.org/10.3390/ijerph17218079 (registering DOI).

Abstract

We investigated whether cellular phone use was associated with increased risk of tumors using a meta-analysis of case-control studies. PubMed and EMBASE were searched from inception to July 2018. The primary outcome was the risk of tumors by cellular phone use, which was measured by pooling each odds ratio (OR) and its 95% confidence interval (CI). In a meta-analysis of 46 case-control studies, compared with never or rarely having used a cellular phone, regular use was not associated with tumor risk in the random-effects meta-analysis. However, in the subgroup meta-analysis by research group, there was a statistically significant positive association (harmful effect) in the Hardell et al. studies (OR, 1.15—95% CI, 1.00 to 1.33— n = 10), a statistically significant negative association (beneficial effect) in the INTERPHONE-related studies (case-control studies from 13 countries coordinated by the International Agency for Research on Cancer (IARC); (OR, 0.81—95% CI, 0.75 to 0.89—n = 9), and no statistically significant association in other research groups’ studies. Further, cellular phone use with cumulative call time more than 1000 hours statistically significantly increased the risk of tumors. This comprehensive meta-analysis of case-control studies found evidence that linked cellular phone use to increased tumor risk.

+Contributed equally to this study as the first author.

Excerpts

3.5. Exposure–Response Relationship Between Use of Cellular Phones and Risk of Tumors

Table 3 shows an exposure-response relationship between cellular phone use and tumor risk. In the subgroup meta-analysis by time since first use or latency, overall the risk of tumors by cellular phone use non-significantly increased from an OR of 0.97 to 1.29 as latency increased from less than 5 years to 10 or more years. This finding was observed in each subgroup meta-analysis by research group. Especially, statistically significant increased tumor risk was observed for latency of 10 or more years in the Hardell studies (OR, 1.62; 1.03 to 2.57; n = 5; I2 = 39.9%). Similarly, the use of cellular phones non-significantly increased the risk of tumors as the cumulative or lifetime use in years and the cumulative number of calls increased in all studies and in each study group. Remarkably, in the subgroup meta-analysis of all studies by cumulative call time, cellular phone use greater than 1000 hours statistically significantly increased the risk of tumors (OR, 1.60; 1.12 to 2.30; n = 8; I2 = 74.5%). Interestingly, the use of cellular phones overall and in the Hardell studies (OR, 3.65; 1.69 to 7.85; n = 2, especially in the Hardell studies) non significantly increased the risk of tumors with cumulative call time of 300–1000 h and more than 1000 h, while it decreased the risk of tumors in most subgroup meta-analyses of the INTERPHONE studies.

5. Conclusions

In sum, the updated comprehensive meta-analysis of case-control studies found significant evidence linking cellular phone use to increased tumor risk, especially among cell phone users with cumulative cell phone use of 1000 or more hours in their lifetime (which corresponds to about 17 min per day over 10 years), and especially among studies that employed high quality methods. Further quality prospective studies providing higher level of evidence than case-control studies are warranted to confirm our findings.

Open access paper and supplemental material: http://bit.ly/cellphonetumor.

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5G Wireless: Capabilities and Challenges for an Evolving Network

U.S. Government Accountability Office (GAO). 5G Wireless: Capabilities and Challenges for an Evolving Network. Nov. 2020, Report to Congressional Requesters GAO-21-26SP: 1-67. https://www.gao.gov/assets/720/710861.pdf.

No abstract.

Excerpts from the report: https://www.saferemr.com/2020/11/GAO-5G-Report-2020.html

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Health Council of the Netherlands Advisory Report: 5G and Health

Committee of the Health Council of the Netherlands. Advisory report. 5G and health. Health Council of the Netherlands. 2020, Advisory report 2020/16e: 1-33.

Executive Summary

The latest standard for mobile telecommunications (5G) is faster and more reliable and can process more data at the same time. 5G was developed to cope with the increasing demand for mobile telecommunications and to make new applications possible such as self-driving cars and remote surgery. The advent of 5G networks is, however, resulting in societal concerns about the potential influence of 5G on health. That is why the House of Representatives of the Dutch parliament has asked the Health Council of the Netherlands to analyse what is known about this from a scientific perspective. The Council’s Standing Committee on Electromagnetic Fields has looked into this issue.

Effects of 5G frequencies on health not yet fully examined

To a certain extent, 5G uses the same frequencies as previous generations of mobile telecommunication such as 3G and 4G. In addition, it will use new frequency bands.The rollout of 5G networks has only just begun.
Therefore, there are no studies as yet into the health effects of (long-term) exposure to electromagnetic fields with the frequencies that are reserved for 5G. However, applications have been examined that use frequencies very close to the new 5G frequencies. These include 2G, 3G and 4G, as well as Wi-Fi and radar.

No actual health risks known

This report is a first step in the analysis of possible health effects of 5G frequencies. As yet, the committee is unable to answer the question of whether exposure to 5G frequencies actually poses risks to human health. There are two reasons for that. The first is that such a statement requires knowledge of the level of exposure that can cause health damage to humans. That requires a more detailed analysis of the scientific data than the committee was able to carry out. The World Health Organization (WHO) is currently performing such an analysis and it is anticipated that it will be completed in 2022. Secondly, it requires knowledge of what the actual exposure to radiofrequency electromagnetic fields will be after the introduction of 5G. That is not yet known, because the use of 5G, as stated earlier, has only partially started.

Relations between 5G frequencies and health damage not demonstrated but cannot be excluded for a number of conditions

Therefore, the committee has investigated whether there are indications that electromagnetic fields with the frequencies of 5G have the potential to harm health. It has reviewed whether relations are known between exposure to radiofrequency electromagnetic fields on the one hand and the occurrence of diseases and conditions on the other. According to the committee, it cannot be excluded that the incidence of cancer, reduced male fertility, poor pregnancy outcomes and birth defects could be associated with exposure to radiofrequency electromagnetic fields. However, the committee deems the relation between exposure and these and other diseases or conditions neither proven nor probable.

The committee has also examined the possible relation between exposure to radiofrequency electromagnetic fields and changes in biological processes. It is probable that changes in electrical activity in the brain are associated with exposure, but it is not known whether that is favourable or unfavourable in health terms. For the majority of other biological processes it has neither been demonstrated nor is it probable that changes in them are associated with exposure to radiofrequency electromagnetic fields, although this cannot be excluded. Only for changes in the immune system and hormone levels, no relation was found. There has been
almost no research into the effects of exposure to frequencies around 26 GHz.

The committee’s recommendations

The committee has made four recommendations to Parliament.

1. Because the lower frequency bands for 5G (up to 3.5 GHz) have already been used for telecommunications applications and Wi-Fi for years without resulting in any proven adverse health effects, the committee sees no reason to stop or restrict the use of these frequency bands. It does however recommend that the exposure should be monitored before, during and after the rollout of the 5G systems. This will show to what extent exposure to radiofrequency electromagnetic fields changes as a result of the introduction of 5G and any long-term health risks can then be estimated better. The WHO analysis can also be used in estimating the risks.

2. The committee recommends doing more research:

• epidemiological research into the relation between exposure to the 5G frequencies used and the incidence of cancer, reduced male fertility, poor pregnancy outcomes and birth defects. An ongoing international study into the use of mobile telephones, in which the Netherlands is participating, can play a role in this.
• experimental research into the health effects of exposure to electromagnetic fields in the 26 GHz frequency band.
• scenario studies to get a picture of the exposure of individuals as a result of wireless communications systems (3G, 4G and 5G).

3. The committee recommends not to use the 26 GHz frequency band for 5G for as long as the potential health risks have not been investigated.

4. Finally, the committee recommends using the latest guidelines from the International Commission on Non-Ionizing Radiation Protection (ICNIRP) as the basis for exposure policy in the Netherlands. Because it cannot be excluded that exposure under the latest ICNIRP standards also has the potential to affect health, the committee recommends to take a cautious approach and keep exposures as low as reasonably achievable.


Note: One of the two Scientific Secretaries for the Health Council of the Netherlands is Eric van Rongen, former Chair and current Vice Chair of the ICNIRP.

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Association Between Mobile Phone Radiation Exposure and the Secretion of Melatonin and Cortisol, Two Markers of the Circadian System: A Review

Brahim Selmaoui, Yvan Touitou. Association Between Mobile Phone Radiation Exposure and the Secretion of Melatonin and Cortisol, Two Markers of the Circadian System: A Review. Bioelectromagnetics. 2020 Nov 25. doi: 10.1002/bem.22310.

Abstract

The extremely important use of mobile phones in the world, at all ages of life, including children and adolescents, leads to significant exposure of these populations to electromagnetic waves of radiofrequency. The question, therefore, arises as to whether exposure to these radiofrequencies (RFs) could lead to deleterious effects on the body's biological systems and health. In the current article, we review the effects, in laboratory animals and humans, of exposure to RF on two hormones considered as endocrine markers: melatonin, a neurohormone produced by the pineal gland and cortisol, a glucocorticosteroid synthesized by the adrenal glands. These two hormones are also considered as markers of the circadian system. The literature search was performed using PubMed, Medline, Web of Sciences (ISI Web of Knowledge), Google Scholar, and EMF Portal. From this review on RF effects on cortisol and melatonin, it appears that scientific papers in the literature are conflicting, showing effects, no effects, or inconclusive data. This implies the need for additional research on higher numbers of subjects and with protocols perfectly controlled with follow-up studies to better determine whether the chronic effect of RF on the biological functioning and health of users exists (or not).


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Association between estimated whole-brain radiofrequency electromagnetic fields dose and cognitive function in preadolescents and adolescents

Alba Cabré-Riera, Luuk van Wel, Ilaria Liorni, Arno Thielens, Laura Ellen Birks, Livia Pierotti, Wout Joseph, Llúcia González-Safont, Jesús Ibarluzea, Amparo Ferrero, Anke Huss, Joe Wiart, Loreto Santa-Marina, Maties Torrent, Tanja Vrijkotte, Myles Capstick, Roel Vermeulen , Martine Vrijheid, Elisabeth Cardis, Martin Röösli, Mònica Guxens. Association between estimated whole-brain radiofrequency electromagnetic fields dose and cognitive function in preadolescents and adolescents. Int J Hyg Environ Health. 2020 Nov 19;231:113659. doi: 10.1016/j.ijheh.2020.113659.

Abstract

Objective: To investigate the association between estimated whole-brain radiofrequency electromagnetic fields (RF-EMF) dose, using an improved integrated RF-EMF exposure model, and cognitive function in preadolescents and adolescents.

Methods: Cross-sectional analysis in preadolescents aged 9-11 years and adolescents aged 17-18 years from the Dutch Amsterdam Born Children and their Development Study (n = 1664 preadolescents) and the Spanish INfancia y Medio Ambiente Project (n = 1288 preadolescents and n = 261 adolescents), two population-based birth cohort studies. Overall whole-brain RF-EMF doses (mJ/kg/day) were estimated for several RF-EMF sources together including mobile and Digital Enhanced Cordless Telecommunications phone calls (named phone calls), other mobile phone uses than calling, tablet use, laptop use (named screen activities), and far-field sources. We also estimated whole-brain RF-EMF doses in these three groups separately (i.e. phone calls, screen activities, and far-field) that lead to different patterns of RF-EMF exposure. We assessed non-verbal intelligence in the Dutch and Spanish preadolescents, information processing speed, attentional function, and cognitive flexibility in the Spanish preadolescents, and working memory and semantic fluency in the Spanish preadolescents and adolescents using validated neurocognitive tests.

Results: Estimated overall whole-brain RF-EMF dose was 90.1 mJ/kg/day (interquartile range (IQR) 42.7; 164.0) in the Dutch and Spanish preadolescents and 105.1 mJ/kg/day (IQR 51.0; 295.7) in the Spanish adolescents. Higher overall estimated whole-brain RF-EMF doses from all RF-EMF sources together and from phone calls were associated with lower non-verbal intelligence score in the Dutch and Spanish preadolescents (-0.10 points, 95% CI -0.19; -0.02 per 100 mJ/kg/day increase in each exposure). However, none of the whole-brain RF-EMF doses was related to any other cognitive function outcome in the Spanish preadolescents or adolescents.

Conclusions: Our results suggest that higher brain exposure to RF-EMF is related to lower non-verbal intelligence but not to other cognitive function outcomes. Given the cross-sectional nature of the study, the small effect sizes, and the unknown biological mechanisms, we cannot discard that our results are due to chance finding or reverse causality. Longitudinal studies on RF-EMF brain exposure and cognitive function are needed.

https://pubmed.ncbi.nlm.nih.gov/33221634/

Conclusion

Adolescence is a cognitive demanding stage of life, and one of the most rapid phases of human development. Therefore, it is important to identify factors that could compromise brain development at this stage and permanently impair cognitive abilities. Our results suggest that overall estimated whole-brain RF-EMF dose and specific dose from phone calls were related to lower non-verbal intelligence in preadolescents. However, our findings also indicate that whole-brain RF-EMF doses were not related to information processing speed, attentional function, visual attention, and cognitive flexibility in preadolescents or to working memory and semantic fluency in both preadolescents and adolescents. Given the cross-sectional nature of the study, the small effect sizes, and the unknown biological mechanisms, we cannot discard that our results might be due to chance finding or reverse causality. Our findings open the field to future longitudinal studies to further investigate the association between brain exposure to RF-EMF and cognitive function.

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Radiofrequency Electromagnetic Fields from Mobile Communication: Description of Modeled Dose in Brain Regions and the Body in European Children and Adolescents

Laura Ellen Birks, Luuk Van Wel, Ilaria Liorni, Livia Pierotti, Mònica Guxens, Anke Huss, Milena Foerster, Myles Capstick, Marloes Eeftens, Hanan El Marroun, Marisa Estarlich , Mara Gallastegi, Llúcia González Safont, Wout Joseph, Loreto Santa-Marina, Arno Thielens, Maties Torrent, Tanja Vrijkotte, Joe Wiart, Martin Röösli, Elisabeth Cardis, Roel Vermeulen, Martine Vrijheid. Radiofrequency Electromagnetic Fields from Mobile Communication: Description of Modeled Dose in Brain Regions and the Body in European Children and Adolescents. Environ Res. 2020 Nov 24;110505. doi: 10.1016/j.envres.2020.110505.

Highlights
• We modeled daily RF dose in the brain and body in European children and adolescents.
• Our modeling combined exposure to near-field and far-field RF sources.
• Adolescents (age 14-18) received more RF dose in the brain than children (age 8-12).
• Subjects received the highest RF dose in the temporal and frontal lobes of brain.
• Calling on 2G networks was the largest contributor to RF dose in the brain.
Abstract

Background: Little is known about radiofrequency electromagnetic fields (RF) from mobile technology and resulting dose in young people. We describe modeled integrated RF dose in European children and adolescents combining own mobile device use and surrounding sources.

Methods: Using an integrated RF model, we estimated the daily RF dose in the brain (whole-brain, cerebellum, frontal lobe, midbrain, occipital lobe, parietal lobe, temporal lobes) and the whole-body in 8,358 children (ages 8-12) and adolescents (ages 14-18) from the Netherlands, Spain, and Switzerland during 2012-2016. The integrated model estimated RF dose from near-field sources (digital enhanced communication technology (DECT) phone, mobile phone, tablet, and laptop) and far-field, surrounding, sources (mobile phone base stations via 3D-radiowave modeling or RF measurements).

Results: Adolescents were more frequent mobile phone users and experienced higher modeled RF doses in the whole-brain (median 330.4 mJ/kg/day) compared to children (median 81.8 mJ/kg/day). Children spent more time using tablets or laptops compared to adolescents, resulting in higher RF doses in the whole-body (median whole-body dose of 81.8 mJ/kg/day) compared to adolescents (41.9 mJ/kg/day). Among brain regions, temporal lobes received the highest RF dose (medians of 274.9 and 1,786.5 mJ/kg/day in children and adolescents, respectively) followed by the frontal lobe. In most children and adolescents, calling on 2G networks was the main contributor to RF dose in the whole-brain (medians of 31.1 and 273.7 mJ/kg/day, respectively).

Conclusion: This first large study of RF dose to the brain and body of children and adolescents, shows that mobile phone calls on 2G networks are the main determinants of brain dose, especially in temporal and frontal lobes, whereas whole-body doses were mostly determined by tablet and laptop use. The modeling of RF doses provides valuable input to epidemiological research and to potential risk management regarding RF exposure in young people.


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Effects of different mobile phone UMTS signals on DNA, apoptosis and oxidative stress in human lymphocytes

Sachin Gulati, Pavol Kosik, Matus Durdik, Milan Skorvaga, Lukas Jakl, Eva Markova, Igor Belyaev. Effects of different mobile phone UMTS signals on DNA, apoptosis and oxidative stress in human lymphocytes.  Environ Pollut. 2020 Dec;267:115632. doi: 10.1016/j.envpol.2020.115632.

Highlights
• Comparatively analyzed genotoxic effects of UMTS signals at different frequency.
• Significant role of UMTS carrier frequency (1977 MHz) in inducing DNA damage.
• No association of UMTS exposure with apoptosis, TP53 mutations and PFG induction.
• Prolonged exposure to microwave radiation may induce genotoxic effects.
Abstract

Different scientific reports suggested a link between exposure to radiofrequency radiation (RF) from mobile communications and induction of reactive oxygen species (ROS) and DNA damage while other studies have not found such a link. However, the available studies are not directly comparable because they were performed at different parameters of exposure, including carrier frequency of RF signal, which was shown to be critical for appearance of the RF effects. For the first time, we comparatively analyzed genotoxic effects of UMTS signals at different frequency channels used by 3G mobile phones (1923, 1947.47, and 1977 MHz). Genotoxicity was examined in human lymphocytes exposed to RF for 1 h and 3 h using complimentary endpoints such as induction of ROS by imaging flow cytometry, DNA damage by alkaline comet assay, mutations in TP53 gene by RSM assay, preleukemic fusion genes (PFG) by RT-qPCR, and apoptosis by flow cytometry. No effects of RF exposure on ROS, apoptosis, PFG, and mutations in TP53 gene were revealed regardless of the UMTS frequency while inhibition of a bulk RNA expression was found. On the other hand, we found relatively small but statistically significant induction of DNA damage in dependence on UMTS frequency channel with maximal effect at 1977.0 MHz. Our data support a notion that each specific signal used in mobile communication should be tested in specially designed experiments to rule out that prolonged exposure to RF from mobile communication would induce genotoxic effects and affect the health of the human population.


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Comparing chromosome damage induced by mobile telephony radiation and a high caffeine dose: Effect of combination and exposure duration

Dimitris J Panagopoulos. Comparing chromosome damage induced by mobile telephony radiation and a high caffeine dose: Effect of combination and exposure duration. Gen Physiol Biophys. 2020 Nov;39(6):531-544. doi: 10.4149/gpb_2020036.

Abstract

I recently reported induction of chromatid-type aberrations in human peripheral blood lymphocytes after a single 15 min exposure to universal mobile telecommunications system (UMTS) mobile telephony (MT) electromagnetic field (EMF) from a mobile phone. Lymphocytes from six healthy subjects were stimulated for mitosis, and exposed during the G2/M phase at 1 cm distance from the handset during an active phone call in "talk" mode. The same type of cells from the same subjects treated with a high caffeine dose (~ 290 times above the permissible single dose for an adult human) exhibited the same type of aberrations in a little smaller but comparable degree. The combination of this caffeine dose and the 15 min MT EMF exposure increased dramatically the number of aberrations in all subjects. The combined effect increased almost linearly with increasing duration of exposure to the MT EMF. Thus, MT EMF exposure ~ 136 times below the official limit (ICNIRP 2020) exerts a genotoxic action even greater than that of a caffeine dose ~ 290 times above the corresponding limit. Therefore, with a reasonable approximation, the limit for MT EMFs should be lowered by at least ~ 4 × 104 times (136 × 290) for short-term exposures, and ~ 4 × 106 times for long-term exposures.


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Effect of mobile phone usage on cognitive functions, sleep pattern, visuospatial ability in Parkinson's patients; a possible correlation with onset of clinical symptoms

Dhruv Tuteja, Nayanatara Arun Kumar, D Shivananda Pai, K Kunal. Effect of mobile phone usage on cognitive functions, sleep pattern, visuospatial ability in Parkinson's patients; a possible correlation with onset of clinical symptoms. J Basic Clin Physiol Pharmacol. 2020 Nov 9;/j/jbcpp.ahead-of-print/jbcpp-2020-0190/jbcpp-2020-0190.xml. doi: 10.1515/jbcpp-2020-0190.

Abstract

Objectives The global increase in various neurological disorders is a serious problem to be concerned. This study mainly focused on the changes in cognitive impairment, sleep pattern, visuospatial ability in the Parkinson's disease (PD) and its possible association with the usage of smartphones durations.

Methods Parkinson's patients (40-60 years) visiting neurology clinics were included in this study. Based on their age the grouping was designed as Group I (>60) and Group II (40-60 years). All the patients were evaluated for the various motor symptoms in the presence of a neurologist and graded accordingly. The non-motor symptoms included the analysis cognitive function and sleep patterns. The mobile phone usage time was also collected. The Hoehn and Yahr system was used as assessment tool for gradations of PD signs.

Results Duration of mobile phone usage in the Parkinson's patients ranging from 45-60 year was more when compared to the patients aged more than 60 years. The usage of mobile phone did not show significant variation on severity of motor symptoms and cognitive functions. Increased incidence of sleep deprivation was observed in the PD patients aged 40-60 years. Increased usage of mobile phone has been inversely associated with the increased progression of the Parkinson's disease.

Conclusion The present study pointed out the significant association of mobile phone usage with the early onset of Parkinsonism.


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The association of smart mobile phone usage with cognitive function impairment in Saudi adult population

Thamir M Al-Khlaiwi, Syed Shahid Habib, Sultan Ayoub Meo, Mohammed S Alqhtani, Abeer A Ogailan. The association of smart mobile phone usage with cognitive function impairment in Saudi adult population. Pak J Med Sci. Nov-Dec 2020;36(7):1628-1633. doi: 10.12669/pjms.36.7.2826.

Abstract

Background & objectives: Excessive use of mobile phones has raised a great concern about adverse health effects on human health. The present study's aim was to investigate the association of the usage of smartphones with cognitive function impairment in the Saudi adult population.

Methods: The present cross-sectional study was conducted in the Department of Physiology, College of Medicine, King Saud University, Riyadh, Saudi Arabia during September 2019 to January 2020. A total of 251 Saudi adults who were using mobile phones were recruited, and knowledge, attitude and practices were assessed by interview using a predesigned proforma. The Montreal Cognitive Assessment (MOCA) tool was employed to assess the cognitive functions, comparison was made between daily mobile phone usage group and their correlated Montreal Cognitive Score (MOCA).

Results: The mean age for 251 Saudi adult participants was 32.43 ± 12.8 years. More than 80% of the participants used their mobile phone for more than two hours daily. About 61% of the participants were not aware of the side effect of the radiation generated from mobile phone. The participants showed a decrease in MOCA score with increased daily mobile phone usage (MOCA=26.8 for <1 hour daily usage, 26.1 for 1-2 hours, and 24.6 for >2 hours with P< 0.05). In addition, participants showed decreased MOCA score by keeping their mobile phone near their pillow while sleeping; MOCA=24.35 for near pillow groups and >25.5 for the groups that placed their mobile phone away from the pillow.

Conclusions: Excessive use of mobile phones can cause cognitive function impairment. Strict policies must be implemented to control the use of smartphones in order to minimize the effects on mobile phone radiation on cognition. The media has to be on the forefront in educating the public about the proper usage of mobile phones.


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Metabolomics and psychological features in fibromyalgia and electromagnetic sensitivity


Cristina Piras, Stella Conte, Monica Pibiri, Giacomo Rao, Sandro Muntoni, Vera Piera Leoni, Gabriele Finco, Luigi Atzori. Metabolomics and psychological features in fibromyalgia and electromagnetic sensitivity.
Sci Rep. 2020 Nov 24;10(1):20418. doi: 10.1038/s41598-020-76876-8.

Abstract

Fibromyalgia (FM) as Fibromyalgia and Electromagnetic Sensitivity (IEI-EMF) are a chronic and systemic syndrome. The main symptom is represented by strong and widespread pain in the musculoskeletal system. The exact causes that lead to the development of FM and IEI-EMF are still unknown. Interestingly, the proximity to electrical and electromagnetic devices seems to trigger and/or amplify the symptoms. We investigated the blood plasma metabolome in IEI-EMF and healthy subjects using 1H NMR spectroscopy coupled with multivariate statistical analysis. All the individuals were subjected to tests for the evaluation of psychological and physical features. No significant differences between IEI-EMF and controls relative to personality aspects, Locus of Control, and anxiety were found. Multivariate statistical analysis on the metabolites identified by NMR analysis allowed the identification of a distinct metabolic profile between IEI-EMF and healthy subjects. IEI-EMF were characterized by higher levels of glycine and pyroglutamate, and lower levels of 2-hydroxyisocaproate, choline, glutamine, and isoleucine compared to healthy subjects. These metabolites are involved in several metabolic pathways mainly related to oxidative stress defense, pain mechanisms, and muscle metabolism. The results here obtained highlight possible physiopathological mechanisms in IEI-EMF patients to be better defined.


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The use of a bed with an insulating system of electromagnetic fields improves immune function, redox and inflammatory states, and decrease the rate of aging


E Díaz-Del Cerro, C Vida, I Martínez de Toda, J Félix, M De la Fuente. The use of a bed with an insulating system of electromagnetic fields improves immune function, redox and inflammatory states, and decrease the rate of aging. Environ Health. 2020 Nov 23;19(1):118. doi: 10.1186/s12940-020-00674-y.

Abstract

Background: The immune system, as a homeostatic system, is an excellent marker of health and has also been proposed as an indicator of the rate of aging. The base of the age-related changes in the immune system, "immunosenescence", is oxidative-inflammatory stress. Studies have shown that long-term exposure to electromagnetic fields (EMFs) produced by technology causes inhibitory effects on the immune response and increases oxidation. The aim of the present study was to investigate the effects of resting on an EMF-insulated system on several immune functions, the oxidative-inflammatory state and subsequently the rate of aging (biological age).

Methods: Several immune functions, in peripheral blood neutrophils and mononuclear cells, of 31 volunteers were analyzed before and after 2 months of using a bed with the patented HOGO system, which insulated participants against EMFs. Several oxidative and inflammatory parameters, in whole blood cells, were also studied. The biological age was calculated using a mathematical formula, which was based on several immune function parameters. A placebo group of 11 people using beds without that property were used as a control.

Results: The results showed a significant improvement of immune functions and antioxidant and anti-inflammatory defenses after using the HOGO system for 2 months. In addition, a decrease in oxidants and pro-inflammatory compounds, a lowering of oxidative damage in lipids and in DNA as well as a reduction of calculated biological age was also observed. The placebo group did not show any changes.

Conclusions: In conclusion, 2 months of resting on a bed insulated from EMFs demonstrates improvement in immune function, oxidative-inflammatory state and biological age.

Open access paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7685570/

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Modelling of Total Exposure in Hypothetical 5G Mobile Networks for Varied Topologies and User Scenarios

Sven Kuehn, Serge Pfeifer, Beyhan Kochali, Niels Kuster. Modelling of Total Exposure in Hypothetical 5G Mobile Networks for Varied Topologies and User Scenarios. Final Report of Project CRR-816. A report on behalf of the Swiss Federal Office for the Environment (FOEN). IT'IS Foundation, Zurich. 24 June 2019.

Executive Summary

In January 2019, the Swiss Federal Office for the Environment (FOEN) mandated the IT’IS Foundation to evaluate the total human exposure in hypothetical 5G mobile networks for varied topologies and user scenarios to identify factors that would minimize the total exposure of the population. In this study, total exposure is defined as the combined exposure from network base stations, the user’s own device, as well as bystanders’ mobile devices.

The influence of various factors on total exposure in mobile communication networks (as defined above) was modeled and analyzed with the help of the Monte Carlo simulation technique. Total exposure is described as the local peak specific absorption rate (SAR) spatially averaged over any 10 g of tissue mass (psaSAR10g) averaged over a period of 6 minutes. The unit psaSAR10g was chosen because it defines the governing basic restriction for wireless exposure as the whole-body average SAR limits (wbaSAR) are intrinsically met if the limits of local exposure are satisfied. The averaging duration of 6 minutes constitutes the internationally accepted averaging time to prevent thermal hazards at frequencies below 6 GHz as instant values have little justification. However, it should be noted that some regulators define shorter averaging time periods, e.g., the US Federal Communications Commission (FCC) of 100 s.

In a first step, we analyzed the tissue-specific exposure as a function of frequency. The preliminary dosimetric study showed that exposure of the human brain to the 3.6 GHz band, that has been recently added to the Swiss mobile communication frequencies, is reduced by a factor of >6 for the tissue averaged SAR when compared to mobile network operation at <1 GHz. This reduction is due to the smaller penetration depth at higher frequencies. This conclusion, however, does not apply to exposed tissues close to the surface or skin (eyes, testicles, etc.) when the peak SAR in this tissue is evaluated. The peak SAR in the grey matter remains in approximately the same order of magnitude ( 3 dB) over all frequencies but the area of high exposure is reduced at 3.6 GHz.

In a second step, we used data measured in 4G systems and analyzed the latest mobile network standards to extrapolate the exposures for various 5G network scenarios. These measured data were also used to extrapolate the exposure to the future development of data usage in 5G networks.

Specifically, we analyzed the effect on the total exposure of (i) the network topology by varying the cell size and amount of indoor coverage in the network, as well as the usage of (ii) an individual’s own device, and (iii) devices of close bystanders.

The results – based on simulations of more than 200 different exposure scenarios – reveal that, for all user types, except for non-users (including passive mobile phone users and users dominantly using downlink data traffic, e.g., video streaming), total exposure is dominated by the person’s own mobile device. Compared to non-users, the exposure is increased (i) for light users (with 100 MByte uplink data per day) by 6 – 10 dB (or a factor of 4 to 10), (ii) for moderate users (with 1 GByte uplink data per day) by 13 – 25 dB (or a factor of 20 to >300), and (iii) for heavy users by 15 – 40 dB (or a factor of 30 to >10000). Further, the results show that peak exposure of non-users is not defined by exposure to base stations but by exposure to mobile devices of close bystanders in urban areas resulting in 6 dB (or a factor of 4) higher exposure than from a nearby base station antenna.

While a reduction of the mobile cell size leads to a reduction in total exposure by a factor of 2 to10 for people actively using their mobile devices, this might also lead to a small increase by a factor of 1.6 in total exposure of non-users due the generally increased incident signal levels from the surrounding base stations.

Similarly, the exposure of active users can be reduced by a factor of 4 to 600 by increasing the indoor network coverage. Yet, in line with the results for the mobile cell sizes, increased indoor coverage will also lead to increased exposure of non-users by a factor of 2 to 10. This increase, however, starts at a level 1000 times lower than the typical total exposure of active users.

The results of this study show that the personal mobile device is the dominant exposure source for active mobile network users. Besides a person’s own usage behavior, total exposure is also closely linked to the network infrastructure. Generally speaking, a network with a lower path loss, i.e., smaller cells and additional indoor coverage, helps to reduce total exposure. The exposure per transmitted bit is reduced by a factor of <3 by the increased spectral efficiency of the 5G technology, and the reduced penetration depth associated with the new bands at 3.5 – 3.8 GHz.

The results presented above are limited due to the network data that has been used and the definition of total exposure as stated in this report. Furthermore, it only considers time-averaged (6 min) and not instant exposures. This study does not consider (i) the effect of upcoming massive MIMO systems in 5G networks, (ii) alternative data transmission links, for instance the use of Wireless Local Area Network (WLAN), and (iii) millimeter wave frequencies in 5G mobile networks.

Conclusions

The results of this study show that the absorption of energy by the human brain, resulting from exposure to the 3.6 GHz band newly added to the Swiss mobile communication frequencies, isreduced by a factor >6 for the tissue averaged SAR when compared to mobile networks operating at <1 GHz, and by a factor of >2 when compared to the frequency bands at 1.8 – 2GHz. For deep brain regions, the reduction is much larger.

The reduced exposure for these regions is due to lower penetration depths at higher frequencies. Close to the surface (eyes, testicles, etc.) the exposure can be higher. At the most exposed surface of the grey matter, the values remain approximately 3 dB over all frequencies whereas the area of high exposure is reduced.

More than 200 Monte Carlo simulated exposure scenarios have been analyzed to evaluate total  human exposure in 5G Networks for different topologies and user scenarios. The results show that for all users (except non-users), the total exposure is dominated by a person’s own mobile device. Compared to a non-user, the exposure is increased for a light user (with 100 MByte uplink data per day) by 6 – 10 dB (or by a factor 4 to 10), for a moderate user (with 1 GByte uplink data per day) by 13 – 25 dB (or by a factor of 20 to >300), and for a heavy user by 25 – 40 dB (or a factor of 300 to >10000). The peak exposure of non-users is further not defined by exposure to surrounding base stations but by mobile devices of close bystanders in urban areas,resulting in 6 dB (or a factor of 4) higher exposure than from a nearby base station antenna.

Reducing the diameter of the mobile cell leads to a decreased overall exposure by a factor of 2 to 10 for people who actively use their mobile devices. At the same time, the reduction in cell size might lead to a small increase by a factor <2 in exposure for non-users. The exposure of active users can be reduced by factors ranging from 4 to 600 by increasing indoor network coverage which, in turn, will be linked to increased exposure of non-users by a factor of 2 to 10. However, such an increase is by a factor 1000 lower than the typical exposure of active users. The results of this study are limited due to the network data that has been used and the definition of total exposure as stated earlier in this report. This study does not consider (i) the effect of upcoming massive MIMO and multi-user MIMO systems in 5G networks, (ii) alternative data transmission links – for instance the use of Wireless Local Area Network (WLAN) and (iii)millimeter wave frequencies in 5G mobile networks.

In summary, the results of this study show that the user’s own mobile device is the dominant source of exposure for the population of active mobile network users. Besides personal usage patterns, totl exposure is also closely linked to the network infrastructure. Generally speaking, a network that decreases the path loss by means of smaller cells and additional indoor coverage will help to reduce the total exposure of the population.


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Radiofrequency exposure of people living near mobile-phone base stations in France


Pascal De Giudici, Jean-Christian Genier, Sylvie Martin, Jean-François Doré, Pierre Ducimetière, Anne-Sophie Evrard, Thierry Letertre, Claire Ségala.Radiofrequency exposure of people living near mobile-phone base stations in France. Environmental Research. Available online 19 November 2020, 110500. https://doi.org/10.1016/j.envres.2020.110500.

Highlights

• Mobile-phone base stations antennas are the dominant source of exposure to electromagnetic fields in surrounding housing.
• Indoor exposure was influenced by the position of the windows with respect to the antenna and the floor of the building.
• Personal electric field measurements showed higher values during trips than at home.
• Personal electric field measurements were higher during the day but not different between working days and weekends.
• Exposure quantified by spot and personal measurements was strongly correlated.

Abstract

In response to the demand from a growing number of people concerned about the possible impact of RF-EMF on health, the French National Frequency Agency (ANFR) has published a standardized protocol for in-situ measurements of radiofrequency electromagnetic fields (RF-EMF). This protocol was based on the search for the point of highest field strength and the use of spot measurement.

In the framework of an epidemiological study, such spot measurements were implemented in the homes of 354 participants located in urban areas within 250 m of a mobile-phone base station (MPBS) and in the main beam direction of the antenna. Among the participants, more than half accepted to be enrolled in a longer-term study, among whom 152 were equipped with a personal exposure meter (PEM) for 48 h and 40 for seven continuous days. Both spot and PEM measurements quantified downlink field strengths, i.e. FM, TV3-4-5, TETRA I-II-III, 2 GHz–5GHz Wi-Fi, WiMax, GSM900, GSM1800, UMTS900, UMTS 2100, LTE800, LTE1800, and LTE2600.

Spot measurements showed a mean/median field strength of 0.58/0.44 V/m for total RF-EMF and 0.43/0.27 V/m from the MPBS. RF-EMF from the MPBS was the dominant source of exposure in 64% of households. Exposure to RF-EMF was influenced by the position of the windows with respect to the MPBS, in particular line-of-site visibility, the distance of the antenna and the floor of the apartment. The PEM surveys showed the measured exposure to be higher during outings than at home and during the day than at night, but there was no difference between the weekends and working days. There was a strong correlation between exposure quantified by both spot and PEM measurements, although spot measures were approximately three times higher than those by PEMs.

This study is the first to assess exposure to RF-EMF of people living near a MPBS in urban areas in France. These preliminary results suggest the value of using spot measurements to estimate the impact of the evolution of the mobile-phone network and technology on the exposure of populations to RF-EMF. The low levels of RF-RMF expressed as mean values do not necessarily rule out possible health effects of this exposure.

Open access paper: https://www.sciencedirect.com/science/article/pii/S0013935120313979

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Assessing The Compliance Of Electromagnetic Fields Radiated by Base Stations And WiFi Access Points With International Guidelines On University Campus

Sajedeh Keshmiri, Neda Gholampour, Vahid Mohtashami. Assessing The Compliance Of Electromagnetic Fields Radiated by Base Stations And wifi Access Points With International Guidelines On University Campus.
Radiat Prot Dosimetry. 2020 Nov 24;ncaa183. doi: 10.1093/rpd/ncaa183.

Abstract

This paper presents a series of electromagnetic field measurements performed on the campus of Ferdowsi University of Mashhad in order to assess the compliance of radiation levels of cellular base stations and WiFi access points with international guidelines. A calibrated, broadband and isotropic probe is used and recommendations of International Telecommunication Union (ITU) are followed up throughout measurements. More than 300 outdoor and indoor locations have been systematically chosen for measurements. The recorded data are post-processed and compared with the guideline of International Commission on Non-Ionizing Radiation Protection (ICNIRP). Measured power densities of WiFi access points are low and do not exceed 1% of the level allowed by ICNIRP. For cellular base stations, measured power density is usually low outdoors, but reaches up to 16% of the allowed radiation level in publicly accessible indoor locations. Comprehensive exposure assessment, as recommended by ITU, has been performed to estimate the maximum possible radiation of one indoor base station. It is concluded that precautionary actions have to be taken by university authorities to limit the presence of students in close proximity to specific indoor antennas. Moreover, comprehensive exposure assessment is more likely necessary for indoor base stations whereas such assessment is not usually required outdoors.


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Radiofrequency Fields and Calcium Movements Into and Out of Cells

Andrew Wood, Ken Karipidis. Radiofrequency Fields and Calcium Movements Into and Out of Cells. Radiat Res. 2020 Nov 18. doi: 10.1667/RADE-20-00101.1.

Abstract

The recent rollout of 5G telecommunications systems has spawned a renewed call to re-examine the possibility of so-called "non-thermal" harmful effects of radiofrequency (RF) radiation. The possibility of calcium being affected by low-level RF has been the subject of research for nearly 50 years and there have been recent suggestions that voltage-gated calcium channels (VGCCs) are "extraordinarily sensitive" to ambient RF fields. This article examines the feasibility of particularly modulated RF coupling to gating mechanisms in VGCCs and also reviews studies from the literature from the last 50 years for consistency of outcome. We conclude that the currents induced by fields at the ICNIRP guideline limits are many orders of magnitude below those needed to affect gating, and there would need to be a biological mechanism for detection and rectification of the extremely-low-frequency (ELF) modulations, which has not been demonstrated. Overall, experimental studies have not validated that RF affects Ca2+ transport into or out of cells.

https://pubmed.ncbi.nlm.nih.gov/33206197/

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Possible effects of different doses of 2.1 GHz electromagnetic radiation on learning, and hippocampal levels of cholinergic biomarkers in Wistar rats

Çiğdem Gökçek-Saraç, Güven Akçay, Serdar Karakurt, Kayhan Ateş, Şükrü Özen, Narin Derin. Possible effects of different doses of 2.1 GHz electromagnetic radiation on learning, and hippocampal levels of cholinergic biomarkers in Wistar rats. Electromagn Biol Med. 2020 Dec 1;1-12. doi: 10.1080/15368378.2020.1851251.

Abstract

The present study evaluated whether short-term exposure to different doses of 2.1 GHz radiofrequency electromagnetic radiation (RF-EMR) has different effects on rats' behaviour and hippocampal levels of central cholinergic biomarkers. Animals were divided into three equal groups namely; group 1 was sham-exposed group, group 2-3 were exposed to 45 V/m and 65 V/m doses of 2.1 GHz frequency for 1 week respectively. Numerical dosimetry simulations were carried out. Object location and Y-maze were used as behavioural tasks. The protein and mRNA expression levels of AChE, ChAT, and VAChT, in the hippocampus were tested using Western Blotting and Real-Time PCR. The impairment performance of rats subjected to 65 V/m dose of 2.1 GHz RF-EMR in both object location and Y-maze tasks was observed. The hippocampal levels of AChE, ChAT, and VAChT, were significantly lower in rats exposed to 65 V/m dose of 2.1 GHz RF-EMR than others. The stronger effect of "65 V/m" dose on both rat's hippocampal-dependent behavioural performances and hippocampal levels of cholinergic biomarkers may be due to the stronger effect of "65 V/m" dose where rats' snouts were located at the nearest distance from the monopole antenna. Furthermore, the simulated SAR values were high for 65 V/m electric-field strengths. For the first time, we report the potential dose-dependent effects of short-term exposure to 2.1 GHz radiation on rat's behavioural performances as well as hippocampal levels of cholinergic biomarkers. Further studies are needed to understand the mechanisms by which RF-EMR influences the function of the central cholinergic system in the brain.

https://pubmed.ncbi.nlm.nih.gov/33259237/

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Morphological changes in the vertebrae and central canal of rat pups born after exposure to the electromagnetic field of pregnant rats

Ayşe İkinci Keleş. Morphological changes in the vertebrae and central canal of rat pups born after exposure to the electromagnetic field of pregnant rats. Acta Histochem. 2020 Nov 12;122(8):151652. doi: 10.1016/j.acthis.2020.151652.

Abstract

Several studies have investigated the effects of the electromagnetic field (EMF) on the central nervous system. However, we encountered no studies of the effects of EMF applied in the prenatal period on the offspring vertebrae. The aim of this study is to investigate the effect of a 900 megahertz (MHz) EMF applied to rat dams in the prenatal period on the vertebrae of rat pups. Female Sprague Dawley rats weighing 180-250 g were used in the experiment. Rats identified as pregnant were divided into two groups, control (n = 3) and EMF (n = 3). No EMF was applied to the control group pregnant rats. EMF was applied to the EMF group rats for 1 h daily on an equal and standard basis on prenatal days 13-21. All newborn rat pups were divided into pup control (n = 6) (PC) and pup EMF (n = 6) (PEMF) groups, and no treatment was performed on either. All animals were decapitated on day 32, and the spinal cord in the upper thoracic region was harvested. Vertebral tissues were subjected to routine histological procedures. Histopathological examination revealed that PEMF group vertebral cartilage had been converted into bone tissue. Comparison of central canal diameter and area values between the PEMF group and the PC group revealed statistically significant increases in the PEMF group (p = 0.000 and p = 0.001, respectively). Statistical analysıs revealed no significant difference in mean body weights between the two groups (p > 0.530). Based on these findings, we think that 900 MHz EMF applied in the prenatal period affects the development of the vertebrae. This effect causes pathological changes in the rat pup vertebrae. These findings now raise the question of whether EMF also has an impact on neurological and neurosurgical diseases involving the vertebrae.


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Long-term 1800MHz electromagnetic radiation did not induce Balb/c-3T3 cells malignant transformation

Zhen Ding, Xiaoyong Xiang, Jintao Li, Shuicai Wu. Long-term 1800MHz electromagnetic radiation did not induce Balb/c-3T3 cells malignant transformation. Electromagn Biol Med. 2020 Nov 19;1-10. doi: 10.1080/15368378.2020.1846194.

Abstract

There is an increased public concern about potential health hazards of exposure to electromagnetic radiation (EMR). To declare the carcinogenic effects of 1800 MHz EMR. In this study, Balb/c-3T3 cells were exposed to 1800 MHz EMR for 80 days. The cells were harvested for cell proliferation detection, cell cycle assay, plate clone, and soft agar formation assay, transwell assay, and mRNA microarray detection. 1800 MHz EMR promoted Balb/c-3T3 proliferation. No clones were observed in both plate clone and soft agar clone formation assay. The percentage of cells in S phase in Balb/c-3T3 cells of 80d Expo was obviously higher than the percetage in 80d Sham cells. 80d Expo Balb/c-3T3 cells had stronger migration ability than Sham cells. The mRNA microarray results indicated that cell cycle, cell division, and DNA replication were the main biological processes the significant genes enriched, with higher expression of RPs and Mcms. 1800 MHz EMR promoted Balb/c-3T3 cells proliferation and migration. The mRNA microarray results indicated that cell cycle, cell division, and DNA replication were the main biological processes the significant genes enriched.


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Exposure of the SH-SY5Y Human Neuroblastoma Cells to 50-Hz Magnetic Field: Comparison Between Two-Dimensional (2D) and Three-Dimensional (3D) In Vitro Cultures

Claudia Consales, Alessio Butera, Caterina Merla, Emanuela Pasquali, Vanni Lopresto, Rosanna Pinto, Maria Pierdomenico, Mariateresa Mancuso, Carmela Marino, Barbara Benassi. Exposure of the SH-SY5Y Human Neuroblastoma Cells to 50-Hz Magnetic Field: Comparison Between Two-Dimensional (2D) and Three-Dimensional (3D) In Vitro Cultures. Mol Neurobiol. 2020 Nov 24. doi: 10.1007/s12035-020-02192-x.

Abstract

We here characterize the response to the extremely low-frequency (ELF) magnetic field (MF, 50 Hz, 1 mT) of SH-SY5Y human neuroblastoma cells, cultured in a three-dimensional (3D) Alvetex® scaffold compared to conventional two-dimensional (2D) monolayers. We proved that the growing phenotype of proliferating SH-SY5Y cells is not affected by the culturing conditions, as morphology, cell cycle distribution, proliferation/differentiation gene expression of 3D-cultures overlap what reported in 2D plates. In response to 72-h exposure to 50-Hz MF, we demonstrated that no proliferation change and apoptosis activation occur in both 2D and 3D cultures. Consistently, no modulation of Ki67, MYCN, CCDN1, and Nestin, of invasiveness and neo-angiogenesis-controlling genes (HIF-1α, VEGF, and PDGF) and of microRNA epigenetic signature (miR-21-5p, miR-222-3p and miR-133b) is driven by ELF exposure. Conversely, intracellular glutathione content and SOD1 expression are exclusively impaired in 3D-culture cells in response to the MF, whereas no change of such redox modulators is observed in SH-SY5Y cells if grown on 2D monolayers. Moreover, ELF-MF synergizes with the differentiating agents to stimulate neuroblastoma differentiation into a dopaminergic (DA) phenotype in the 3D-scaffold culture only, as growth arrest and induction of p21, TH, DAT, and GAP43 are reported in ELF-exposed SH-SY5Y cells exclusively if grown on 3D scaffolds. As overall, our findings prove that 3D culture is a more reliable experimental model for studying SH-SY5Y response to ELF-MF if compared to 2D conventional monolayer, and put the bases for promoting 3D systems in future studies addressing the interaction between electromagnetic fields and biological systems.


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Effect of Intermittent ELF MF (Extremely Low Frequency Magnetic Fields) on Umbilical Cord Blood Lymphocytes

Lucián Zastko, Leonardo Makinistian, Andrea Moravčíková, Ján Jakuš, Igor Belyaev. Effect of Intermittent ELF MF on Umbilical Cord Blood Lymphocytes. Bioelectromagnetics. 2020 Nov 15. doi: 10.1002/bem.22302.

No abstract


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Exposure To Extremely Low-Frequency Magnetic Fields In Low- And Middle-Income Countries: An Overview

Dan Baaken, Daniel Wollschläger, Theodoros Samaras, Joachim Schüz , Isabelle Deltour. Exposure To Extremely Low-Frequency Magnetic Fields In Low- And Middle-Income Countries: An Overview.
Radiat Prot Dosimetry. 2020 Nov 24;ncaa172. doi: 10.1093/rpd/ncaa172.

Abstract

To compare extremely low-frequency magnetic field (ELF-MF) exposure in the general population in low- and middle-income countries (LMICs) with high-income countries (HIC), we carried out a systematic literature search resulting in 1483 potentially eligible articles; however, only 25 studies could be included in the qualitative synthesis. Studies showed large heterogeneity in design, exposure environment and exposure assessment. Exposure assessed by outdoor spot measurements ranged from 0.03 to 4μT. Average exposure by indoor spot measurements in homes ranged from 0.02 to 0.4μT. Proportions of homes exposed to a threshold of ≥0.3μT were many times higher in LMICs compared to HIC. Based on the limited data available, exposure to ELF-MF in LMICs appeared higher than in HIC, but a direct comparison is hampered by a lack of representative and systematic monitoring studies. Representative measurement studies on residential exposure to ELF-MF are needed in LMICs together with better standardisation in the reporting.


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Physiological Ca 2+ Transients Versus Pathological Steady-State Ca 2+ Elevation, Who Flips the ROS Coin in Skeletal Muscle Mitochondria

Ang Li, Jianxun Yi, Xuejun Li, Jingsong Zhou. Physiological Ca 2+ Transients Versus Pathological Steady-State Ca 2+ Elevation, Who Flips the ROS Coin in Skeletal Muscle Mitochondria. Front Physiol. 2020 Oct 22;11:595800. doi: 10.3389/fphys.2020.595800.

Abstract

Mitochondria are both the primary provider of ATP and the pivotal regulator of cell death, which are essential for physiological muscle activities. Ca2+ plays a multifaceted role in mitochondrial function. During muscle contraction, Ca2+ influx into mitochondria activates multiple enzymes related to tricarboxylic acid (TCA) cycle and oxidative phosphorylation, resulting in increased ATP synthesis to meet the energy demand. Pathophysiological conditions such as skeletal muscle denervation or unloading also lead to elevated Ca2+ levels inside mitochondria. However, the outcomes of this steady-state elevation of mitochondrial Ca2+ level include exacerbated reactive oxygen species (ROS) generation, sensitized opening of mitochondrial permeability transition pore (mPTP), induction of programmed cell death, and ultimately muscle atrophy. Previously, both acute and long-term endurance exercises have been reported to activate certain signaling pathways to counteract ROS production. Meanwhile, electrical stimulation is known to help prevent apoptosis and alleviate muscle atrophy in denervated animal models and patients with motor impairment. There are various mechanistic studies that focus on the excitation-transcription coupling framework to understand the beneficial role of exercise and electrical stimulation. Interestingly, a recent study has revealed an unexpected role of rapid mitochondrial Ca2+ transients in keeping mPTP at a closed state with reduced mitochondrial ROS production. This discovery motivated us to contribute this review article to inspire further discussion about the potential mechanisms underlying differential outcomes of physiological mitochondrial Ca2+ transients and pathological mitochondrial Ca2+ elevation in skeletal muscle ROS production.

Open access paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7642813