2.14-GHz electromagnetic field exposure at a specific absorption rate of 4 W/kg induced increases in the core temperature and upregulation of some stress markers in the brains of rats.

PMID: 

J Toxicol Sci. 2016 ;41(5):655-66. PMID: 27665775

Abstract Title: 

Exposure time-dependent thermal effects of radiofrequency electromagnetic field exposure on the whole body of rats.

Abstract: 

We investigated the thermal effects of radiofrequency electromagnetic fields (RF-EMFs) on the variation in core temperature and gene expression of some stress markers in rats. Sprague-Dawley rats were exposed to 2.14 GHz wideband code division multiple access (W-CDMA) RF signals at a whole-body averaged specific absorption rate (WBA-SAR) of 4 W/kg, which causes behavioral disruption in laboratory animals, and 0.4 W/kg, which is the limit for the occupational exposure set by the International Commission on Non-Ionizing Radiation Protection guideline. It is important to understand the possible in vivo effects derived from RF-EMF exposures at these intensities. Because of inadequate data on real-time core temperature analyses using free-moving animal and the association between stress and thermal effects of RF-EMF exposure, we analyzed the core body temperature under nonanesthetic condition during RF-EMF exposure. The results revealed that the core temperature increased by approximately 1.5°C compared with the baseline and reached a plateau till the end of RF-EMF exposure. Furthermore, we analyzed the gene expression of heat-shock proteins (Hsp) and heat-shock transcription factors (Hsf) family after RF-EMF exposure. At WBA-SAR of 4 W/kg, some Hsp and Hsf gene expression levels weresignificantly upregulated in the cerebral cortex and cerebellum following exposure for 6 hr/day but were not upregulated after exposure for 3 hr/day. On the other hand, there was no significant change in the core temperature and gene expression at WBA-SAR of 0.4 W/kg. Thus, 2.14-GHz RF-EMF exposureat WBA-SAR of 4 W/kg induced increases in the core temperature and upregulation of some stress markers, particularly in the cerebellum.

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Weak static magnetic fields can accelerate the development of skeletal muscles in vitro.

PMID: 

Bioelectromagnetics. 2014 Dec ;35(8):537-46. Epub 2014 Sep 29. PMID: 25266690

Abstract Title: 

Effect of weak static magnetic fields on the development of cultured skeletal muscle cells.

Abstract: 

We studied the effect produced on the development and functional activity of skeletal muscle cells from newborn Wistar rats in primary culture by weak static magnetic fields (WSMF; 60-400µT) with a high capacity of penetrating the biological media. To reduce the impact of external magnetic fields, cells were cultured at 37 °C in a multilayered shielding chamber with the attenuation coefficient equal to 160. WSMF inside the chamber was created by a circular permanent magnet. We found that the application of WSMF with the magnetic field strength only a few times that of the geomagnetic field can accelerate the development of skeletal muscle cells, resulting in the formation of multinuclear hypertrophied myotubes. WSMF was shown to induce 1.5- to 3.5-fold rise in the concentration of intracellular calcium [Ca(2+)]i due to the release of Ca(2+) from the sarcoplasmic reticulum (SR) through ryanodine receptors (RyR), which increases in the maturation of myotubes. We also found that fully differentiated myotubes at late stages of development were less sensitive to WSMF, manifesting a gradual decrease in the frequency of contractions. However, myotubes at the stage when electromechanical coupling was forming dramatically reduced the frequency of contractions during the first minutes of their exposure to WSMF.

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The effects of extremely low electromagnetic fields on keratinocytes is cell type-dependent.

PMID: 

PLoS One. 2014 ;9(11):e113424. Epub 2014 Nov 19. PMID: 25409520

Abstract Title: 

Distinct epidermal keratinocytes respond to extremely low-frequency electromagnetic fields differently.

Abstract: 

Following an increase in the use of electric appliances that can generate 50 or 60 Hz electromagnetic fields, concerns have intensified regarding the biological effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on human health. Previous epidemiological studies have suggested the carcinogenic potential of environmental exposure to ELF-EMFs, specifically at 50 or 60 Hz. However, the biological mechanism facilitating the effects of ELF-EMFs remains unclear. Cellular studies have yielded inconsistent results regarding the biological effects of ELF-EMFs. The inconsistent results might have been due to diverse cell types. In our previous study, we indicated that 1.5 mT, 60 Hz ELF-EMFs will cause G1 arrest through the activation of the ATM-Chk2-p21 pathway in human keratinocyte HaCaT cells. The aim of the current study was to investigate whether ELF-EMFs cause similar effects in a distinct epidermal keratinocyte, primary normal human epidermal keratinocytes (NHEK), by using the same ELF-EMF exposure system and experimental design. We observed that ELF-EMFs exerted no effects on cell growth, cell proliferation, cell cycle distribution, and the activation of ATM signaling pathway in NHEK cells. We demonstrated that the 2 epidermal keratinocytes responded to ELF-EMFs differently. To further validate this finding, we simultaneously exposed the NHEK and HaCaT cells to ELF-EMFs in the same incubator for 168 h and observed the cell growths. The simultaneous exposure of the two cell types results showed that the NHEK and HaCaT cells exhibited distinct responses to ELF-EMFs. Thus, we confirmed that the biological effects of ELF-EMFs in epidermal keratinocytes are cell type specific. Our findings may partially explain the inconsistent results of previous studies when comparing results across various experimental models.

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Short term exposure to electromagnetic fields induces oxidative stress in the teeth of growing rats.

PMID: 

Biol Trace Elem Res. 2015 Feb ;163(1-2):193-201. Epub 2014 Nov 14. PMID: 25395122\

Abstract Title: 

Effects of prenatal and postnatal exposure of Wi-Fi on development of teeth and changes in teeth element concentration in rats. [corrected].

Abstract: 

The present study determined the effects of prenatal and postnatal exposure to Wi-Fi (2.45 GHz)-induced electromagnetic radiation (EMR) on tooth and surrounding tissue development as well as the element levels in growing rats. Twenty-four rats and their offspring were equally divided into two separate groups identified as experiment and control. The experiment group was exposed to 2.45 GHz EMR for 2 h/day during the periods of pregnancy (21 days) and lactation (21 days). The offspring of these dams were also exposed to EMR up to decapitation. The control group was exposed to cage stress for 2 h per day using the same protocol established for the experimental group. On the 7th,14th, and 21st days after birth, 8 male offspring rats from each of the two groups were decapitated, and the jaws were taken for histological and immunohistochemical examination. Caspase-3 (1/50 dilution) was used in the immunohistochemical examination for apoptotic activity. On the last day of theexperiment, the rats' incisors were also collected. In samples that were histologically and immunohistochemically examined, there was an increase in apoptosis and caspase-3 in both the control and the Wi-Fi groups during the development of the teeth. However, no significant difference was observedbetween the two groups in terms of development and apoptotic activity. Results from the elemental analysis showed that iron and strontium concentrations were increased in the Wi-Fi group, whereas boron, copper, and zinc concentrations were decreased. There were no statistically significant differences in calcium, cadmium, potassium, magnesium, sodium, or phosphorus values between the groups. Histological and immunohistochemical examinations between the experimental and control groups showed that exposure to 2.45 GHz EMR for 2 h per day does not interfere with the development of teeth and surrounding tissues. However, there were alterations in the elemental composition of the teeth, especially affecting such oxidative stress-related elements as copper, zinc, and iron, suggesting that short-term exposure to Wi-Fi-induced EMR may cause an imbalance in the oxidative stress condition in theteeth of growing rats.

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Beginning cell phone use earlier in life increased the odd ratio for glioma in this study.

PMID: 

Pathophysiology. 2015 Mar ;22(1):1-13. Epub 2014 Oct 29. PMID: 25466607

Abstract Title: 

Mobile phone and cordless phone use and the risk for glioma – Analysis of pooled case-control studies in Sweden, 1997-2003 and 2007-2009.

Abstract: 

We made a pooled analysis of two case-control studies on malignant brain tumours with patients diagnosed during 1997-2003 and 2007-2009. They were aged 20-80 years and 18-75 years, respectively, at the time of diagnosis. Only cases with histopathological verification of the tumour were included. Population-based controls, matched on age and gender, were used. Exposures were assessed by questionnaire. The whole reference group was used in the unconditional regression analysis adjusted for gender, age, year of diagnosis, and socio-economic index. In total, 1498 (89%) cases and 3530 (87%) controls participated. Mobile phone use increased the risk of glioma, OR=1.3, 95% CI=1.1-1.6 overall, increasing to OR=3.0, 95% CI=1.7-5.2 in the>25 year latency group. Use of cordless phones increased the risk to OR=1.4, 95% CI=1.1-1.7, with highest risk in the>15-20 years latency group yielding OR=1.7, 95% CI=1.1-2.5. The OR increased statistically significant both per 100h of cumulative use, and per year of latency for mobile and cordless phone use. Highest ORs overall were found for ipsilateral mobile or cordless phone use, OR=1.8, 95% CI=1.4-2.2 and OR=1.7, 95% CI=1.3-2.1, respectively. The highest risk was found for glioma in the temporal lobe. First use of mobile or cordless phone before the age of 20 gave higher OR for glioma than in later age groups.

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Male rats exposed to 9.4GHz microwave radiation in utero exhibit postnatal decreased learning and memory.

PMID: 

J Radiat Res. 2015 Mar ;56(2):261-8. Epub 2014 Oct 30. PMID: 25359903

Abstract Title: 

Effects of fetal microwave radiation exposure on offspring behavior in mice.

Abstract: 

The recent rapid development of electronic communication techniques is resulting in a marked increase in exposure of humans to electromagnetic fields (EMFs). This has raised public concerns about the health hazards of long-term environmental EMF exposure for fetuses and children. Some studies have suggested EMF exposure in children could induce nervous system disorders. However, gender-dependent effects of microwave radiation exposure on cognitive dysfunction have not previously been reported. Here we investigated whether in utero exposure to 9.417-GHz microwave throughout gestation (Days 3.5-18) affected behavior, using the open field test (OFT), elevated-plus maze (EPM), tail suspension test (TST), forced swimming test (FST) and Morris water maze (MWM). We found that mice showed less movement in the center of an open field (using the OFT) and in an open arm (using the EPM) after in utero exposure to 9.417-GHz radiation, which suggested that the mice had increased anxiety-related behavior. Mice demonstrated reduced immobility in TST and FST after in utero exposure to 9.417-GHz radiation, which suggested that the mice had decreased depression-related behavior. From the MWM test, we observed that male offspring demonstrated decreased learning and memory, while females were not affected in learning and memory, which suggested that microwaves had gender-dependent effects. In summary, we have provided the first experimental evidence of microwaves inducing gender-dependent effects.

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Power frequency magnetic fields triggers autophagy in a reactive oxygen species-dependent manner.

PMID: 

Int J Biochem Cell Biol. 2014 Dec ;57:108-14. Epub 2014 Oct 19. PMID: 25450462

Abstract Title: 

Power frequency magnetic fields induced reactive oxygen species-related autophagy in mouse embryonic fibroblasts.

Abstract: 

Power frequency magnetic fields (PFMF) have been reported to affect several cellular functions, such as cell proliferation and apoptosis. In this study, we investigated the effects of PFMF on mouse embryonic fibroblasts (MEF) autophagy. After cells were exposed to 50 Hz PFMF at 2 mT for 0.5 h, 2 h, 6 h, 12 h, and 24 h, we observed a significant increase in autophagic markers at 6 h, including (i) higher microtubule-associated protein 1 light chain 3-II (LC3-II), (ii) the increased formation of GFP-LC3 puncta, and (iii) increased numbers of autophagic vacuoles under transmission electron microscope. Moreover, we provide convincing evidence using chloroquine (CQ) that the increase of autophagic markers was the result of enhanced autophagic flux and not the suppression of lysosomal function. In a search for molecular mechanisms underlying PFMF-mediated autophagy, we observe that the autophagic process involved reactive oxygen species (ROS) and was independent of the mammalian target of rapamycin (mTOR) signaling pathway.

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Influence of electromagnetic fields on the rat stress system is dependent on the time of exposure.

PMID: 

Biomol Ther (Seoul). 2014 Nov ;22(6):570-6. Epub 2014 Nov 30. PMID: 25489427

Abstract Title: 

Effects of electromagnetic radiation exposure on stress-related behaviors and stress hormones in male wistar rats.

Abstract: 

Studies have demonstrated that electromagnetic waves, as the one of the most important physical factors, may alter cognitive and non-cognitive behaviors, depending on the frequency and energy. Moreover, non-ionizing radiation of low energy waves e.g. very low frequency waves could alter this phenomenon via alterations in neurotransmitters and neurohormones. In this study, short, medium, and long-term exposure to the extremely low frequency electromagnetic field (ELF-EMF) (1 and 5 Hz radiation) on behavioral, hormonal, and metabolic changes in male Wistar rats (250 g) were studied. In addition, changes in plasma concentrations for two main stress hormones, noradrenaline and adrenocorticotropic hormone (ACTH) were evaluated. ELF-EMF exposure did not alter body weight, and food and water intake. Plasma glucose level was increased and decreased in the groups which exposed to the 5 and 1Hz wave, respectively. Plasma ACTH concentration increased in both using frequencies, whereas nor-adrenaline concentration showed overall reduction. At last, numbers of rearing, sniffing, locomotor activity was increased in group receiving 5 Hz wave over the time. In conclusions, these data showed that the effects of 1 and 5 Hz on the hormonal, metabolic and stress-like behaviors may be different. Moreover, the influence of waves on stress system is depending on time of exposure.

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Collection of mobile phone operator data may be a more accurate way to assess risks associated with cell phone usage.

PMID: 

J Expo Sci Environ Epidemiol. 2015 Jan ;25(1):72-9. Epub 2014 Nov 5. PMID: 25352163

Abstract Title: 

Validation of self-reported start year of mobile phone use in a Swedish case-control study on radiofrequency fields and acoustic neuroma risk.

Abstract: 

The possible effect of radiofrequency exposure from mobile phones on tumor risk has been studied since the late 1990s. Yet, empirical information about recall of the start of mobile phone use among adult cases and controls has never been reported. Limited knowledge about recall errors hampers interpretations of the epidemiological evidence. We used network operator data to validate the self-reported start year of mobile phone use in a case-control study of mobile phone use and acoustic neuroma risk. The answers of 96 (29%) cases and 111 (22%) controls could be included in the validation. The larger proportion of cases reflects a more complete and detailed reporting of subscription history. Misclassification was substantial, with large random errors, small systematic errors, and no significant differences between cases and controls. The average difference between self-reported and operator start year was -0.62 (95% confidence interval: -1.42, 0.17) years for cases and -0.71 (-1.50, 0.07) years for controls, standard deviations were 3.92 and 4.17 years, respectively. Agreement between self-reported and operator-recorded data categorized into short, intermediate and long-term use was moderate (kappa statistic: 0.42). Should an association exist, dilution of risk estimates and distortion of exposure-response patterns for time since first mobile phone use could result from the large random errors in self-reported start year. Retrospective collection of operator data likely leads to a selection of"good reporters", with a higher proportion of cases. Thus, differential recall cannot be entirely excluded.

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Melatonin prevents liver injury by microwave radiation in rats.

PMID: 

Bratisl Lek Listy. 2015 ;116(2):96-100. PMID: 25665474

Abstract Title: 

The effect of melatonin on the liver of rats exposed to microwave radiation.

Abstract: 

OBJECTIVES: We aimed to clarify if melatonin treatment (2 mg/kg i.p.) may favorably impact the liver tissue in rats exposed to microwave radiation. The experiment was performed on 84 six-weeks-old Wistar male rats exposed for 4h a day, for 20, 40 and 60 days, respectively, to microwaves (900 MHz, 100-300 microT, 54-160 V/m). Rats were divided in to four groups: I (control) – rats treated with saline, II (Mel) – rats treated with melatonin, III (MWs) – microwave exposed rats, IV (MWs + Mel) – MWs exposed rats treated with melatonin. We evaluated oxidative stress parameters (malondialdehyde and carbonyl group content), catalase, xanthine oxidase, deoxyribonuclease I and II activity.BACKGROUND: Oxidative stress is the key mechanism of the microwave induced tissue injury. Melatonin, a lipophilic indoleamine primarily synthesized and released from the pineal gland is a powerful antioxidant.RESULTS: Exposure to microwaves caused an increase in malondialdehyde after 40 (p

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