Monday, November 6, 2023

Recent Research on Wireless Radiation and Electromagnetic Fields

I have been circulating abstracts of newly-published scientific papers on radio frequency and other non-ionizing electromagnetic fields (EMF) monthly since 2016. The complete collection contains more than 1,900 abstracts and links to more than 2,000 papers. Several hundred EMF scientists around the world receive these updates.

To download Volume 2 which contains abstracts of papers published from 2021 on
(including the new papers listed below) click on the following link (808 page pdf):

To download Volume 1 which contains abstracts of papers published from 2016 through 2020
click on the following link (875 page pdf):

The abstracts for recently published papers appear below.


Mobile phone use and risks of overall and 25 site-specific cancers: a prospective study from the UK Biobank Study

Zhang Y, Zhang Y, Ye Z, Yang S, Liu M, Wu Q, Zhou C, He P, Gan X, Qin X. Mobile phone use and risks of overall and 25 site-specific cancers: a prospective study from the UK Biobank Study. Cancer Epidemiol Biomarkers Prev (2023). doi: 10.1158/1055-9965.EPI-23-0766/729762.

Abstract

Background: The association between mobile phone use and incident cancers remains uncertain. We aimed to investigate the relationships of mobile phone use with incident overall and 25 site-specific cancers in men and women. 

Methods: 431,861 participants aged 38-73 years without prior cancers were included from the UK Biobank. Of these, 46.7% were male. Participants who used a mobile phone at least once per week to make or receive calls were defined as mobile phone users. The study outcomes were incident overall and 25 site-specific cancers. 

Results: During a median follow-up of 10.7 years, 35,401 (17.5%) men and 30,865 (13.4%) women developed overall cancer. Mobile phone use was significantly associated with higher risks of incident overall cancer (HR, 1.09; 95%CI: 1.06-1.12), nonmelanoma skin cancer (NMSC) (HR, 1.08; 95%CI: 1.03-1.14), urinary tract cancer (HR, 1.18; 95%CI:1.05-1.32) and prostate cancer (HR, 1.19; 95%CI: 1.13-1.25) in men, and incident overall cancer (HR, 1.03; 95%CI: 1.00-1.06), NMSC (HR, 1.07; 95%CI: 1.01-1.13), and vulva cancer (HR,1.74; 95%CI: 1.00-3.02) in women, but not with other cancers. Among mobile phone users, there was a dose-response relationship of length of mobile phone use with incident NMSC in men and women, and prostate cancer in men (all P for trend<0.05). 

Conclusions: There was a dose-response relationship of length of mobile phone use with incident NMSC in men and women, and prostate cancer in men. Impact: Our findings underscore the importance of limiting mobile phone use or keeping a distance from mobile phone for primary prevention of NMSC and prostate cancer.

Excerpts

Among mobile phone users, there was a significantly positive dose-response relationship of length of mobile phone use (≤1, 2-4, 5-8, and >8 years) with incident overall cancer in both men (P for trend <0.001) and women (P for trend =0.025), incident NMSC in both men (P for trend <0.001) and women (P for trend =0.004), and prostate cancer (P for trend <0.001) in men (Table 2), but not with urinary tract cancer in men and vulva cancer in women (Table 2). There was only a slight difference in follow-up time among different groups of length of mobile phone use (all differences < 0.5 year; Supplemental Table 9), so the groups classified by length of mobile phone use based on baseline assessments should not have changed substantially during follow-up. In addition, treating length of mobile phone use as a time-dependent variable did not significantly change the results (Supplemental Table 10)....

Findings of the current study imply a possible causal relationship of mobile phone use with incident NMSC and prostate cancer: (1) Dose-response relationship of anatomical distance: skin is the first organ to be exposed to RF-EMF. When carrying a mobile phone on the belt or in a pants pocket, it is closer to the prostate. Previous studies have shown that the distance of the source of RF-EMF from the tissue or organ is one of the determinants of corresponding specific absorption rate 21, 22, and thus the relatively close distance of skin and prostate with mobile phones may partly explain the observed increase risks of NMSC and prostate cancer; (2) Temporal relationship: there was a significant association of mobile phone use at baseline with the risks of NMSC and prostate cancer during the 10.7 years of follow-up; (3) Dose-response relationship of exposure time: among mobile phone users, there was a significantly positive dose-response relationship of length of mobile phone use with incident NMSC and prostate cancer. In addition, we found that length of mobile phone use, rather than weekly usage of mobile phone, was associated with incident cancers, suggesting that long-term exposure to RF-EMF might be more important in terms of the risk of incident cancers than short-term, high dose exposure to RF-EMF from making or receiving calls. However, more studies are needed to further confirm our results and elucidate the underlying biological mechanisms....

In conclusion, the current study found that there was a positive dose-response relationship between length of mobile phone use and risk of incident NMSC in both men and women and prostate cancer in men. The potential association of mobile phone use with the risk of urinary tract cancer in men and vulva cancer in women needs to be further verified. If further confirmed, our findings underscore the importance of limiting mobile phone use or keeping a distance from mobile phone for primary prevention of NMSC and prostate cancer in the general population.


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Association between self-reported mobile phone use and the semen quality of young men

Rita Rahban, Alfred Senn, Serge Nef, Martin Rӧӧsli. Association between self-reported mobile phone use and the semen quality of young men. Fertility and Sterility, 2023, doi: 10.1016/j.fertnstert.2023.09.009.

Abstract

Objectives  To investigate the association between mobile phone exposure and semen parameters.

Design  A nationwide cross-sectional study.

Setting  Andrology laboratories in close proximity to 6 army recruitment centers.

Patients  In total, 2886 men from the general Swiss population, 18–22 years old, were recruited between 2005 and 2018 during military conscription.

Intervention  Participants delivered a semen sample and completed a questionnaire on health and lifestyle, including the number of hours they spent using their mobile phones and where they placed them when not in use.

Main Outcome Measures  Using logistic and multiple linear regression models, adjusted odds ratios and β coefficients were determined, respectively. The association between mobile phone exposure and semen parameters such as volume, sperm concentration, total sperm count (TSC), motility, and morphology was then evaluated.

Results  A total of 2759 men answered the question concerning their mobile phone use, and 2764 gave details on the position of their mobile phone when not in use. In the adjusted linear model, a higher frequency of mobile phone use (>20 times per day) was associated with a lower sperm concentration (adjusted β: −0.152; 95% confidence interval: −0.316; 0.011) and a lower TSC (adjusted β: −0.271; 95% confidence interval: −0.515; −0.027). In the adjusted logistic regression model, this translates to a 30% and 21% increased risk for sperm concentration and TSC to be below the World Health Organization reference values for fertile men, respectively. This inverse association was found to be more pronounced in the first study period (2005–2007) and gradually decreased with time (2008–2011 and 2012–2018). No consistent associations were observed between mobile phone use and sperm motility or sperm morphology. Keeping a mobile phone in the pants pocket was not found to be associated with lower semen parameters.

Conclusion  This large population-based study suggests that higher mobile phone use is associated with lower sperm concentration and TSC. The observed time trend of decreasing association is in line with the transition to new technologies and the corresponding decrease in mobile phone output power. Prospective studies with improved exposure assessment are needed to confirm whether the observed associations are causal.

Excerpts

... The energy absorbed by the body depends mainly on the transmission duration, the source’s strength, and the distance to the source. The specific absorption rate decreases with the square of the distance to the source, although the situation can be much more complex close to the source. In addition to potential inaccuracies in reporting hours per day of mobile phone use, radiofrequency exposure depends on characteristics that were not collected, such as brand and generation of the mobile phone, applications on the phone, network quality, distance to base stations, and use of earpieces and protective covers (46, 47). With technical development, the output power of mobile phones has decreased as 3G phones emit, on average, 100–500 times lower levels than 2G phones. In contrast, modern smartphones are much more active in standby mode compared with previous bar phones (48). Therefore, the number of applications on the phone and whether the person is stationary or not may play an important role. During traveling, for example, mobile phones are connecting more frequently and with higher output power on average (49). Such limitations, together with random errors in self-reported use, cause nondifferential exposure misclassification, which would attenuate our estimates and should be considered when interpreting the data....

Conclusion

The lack of clear evidence for a negative association between mobile phone use and male fertility, as well as the dramatic increase in cell phone use over the past decade, underscores the need for further research in this area. From this perspective, it is important to conduct prospective observational studies with men from the general population and to accurately measure the RF-EMF exposure to the testicles and the hypothalamic-pituitary-gonadal axis. This would allow us to examine the association between cell phone use, RF-EMF exposure, and semen quality and to better understand the mode of action of RF-EMF on the male reproductive system.

Open access paper: https://www.fertstert.org/article/S0015-0282(23)01875-7/fulltext

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Assessment of Electrical Brain Activity of Healthy Volunteers Exposed to 3.5 GHz of 5G Signals within Environmental Levels: A Controlled–Randomised Study

My note: Contrary to the authors' claims, the signal generator employed in this study (SMB100A [1406.6000.02], Rohde & Schwarz GmbH & Co KG, Munich, Germany) cannot produce a 5G signal.

Jamal L, Yahia-Cherif L, Hugueville L, Mazet P, Lévêque P, Selmaoui B. Assessment of Electrical Brain Activity of Healthy Volunteers Exposed to 3.5 GHz of 5G Signals within Environmental Levels: A Controlled–Randomised Study. International Journal of Environmental Research and Public Health. 2023; 20(18):6793. doi: 10.3390/ijerph20186793.

Abstract

Following the recent deployment of fifth-generation (5G) radio frequencies, several questions about their health impacts have been raised. Due to the lack of experimental research on this subject, the current study aimed to investigate the bio-physiological effects of a generated 3.5 GHz frequency. For this purpose, the wake electroencephalograms (EEG) of 34 healthy volunteers were explored during two “real” and “sham” exposure sessions. The electromagnetic fields were antenna-emitted in an electrically shielded room and had an electrical field root-mean-square intensity of 2 V/m, corresponding to the current outdoor exposure levels. The sessions were a maximum of one week apart, and both contained an exposure period of approximately 26 min and were followed by a post-exposure period of 17 min. The power spectral densities (PSDs) of the beta, alpha, theta, and delta bands were then computed and corrected based on an EEG baseline period. This was acquired for 17 min before the subsequent phases were recorded under two separate conditions: eyes open (EO) and eyes closed (EC). A statistical analysis showed an overall non-significant change in the studied brain waves, except for a few electrodes in the alpha, theta, and delta spectra. This change was translated into an increase or decrease in the PSDs, in response to the EO and EC conditions. In conclusion, this study showed that 3.5 GHz exposure, within the regulatory levels and exposure parameters used in this protocol, did not affect brain activity in healthy young adults. Moreover, to our knowledge, this was the first laboratory-controlled human EEG study on 5G effects. It attempted to address society’s current concern about the impact of 5G exposure on human health at environmental levels.


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4G mobile phone radiation alters some immunogenic and vascular gene expressions, and gross and microscopic and biochemical parameters in the chick embryo model

Islam MS, Islam MM, Rahman MM, Islam K. 4G mobile phone radiation alters some immunogenic and vascular gene expressions, and gross and microscopic and biochemical parameters in the chick embryo model. Vet Med Sci. 2023 Sep 19. doi: 10.1002/vms3.1273.

Abstract

Background: The risks to human health have grown over the past 10 years due to the excessive use of mobile phones.

Objectives: The study was designed to determine the harmful effects of 4G mobile phone radiation on the expression of immunogenic and vascular genes and gross, microscopic and biochemical alterations in the development of chicken embryos.

Methods: Sixty individuals in the exposure group were subjected to mobile phones with a specific absorption rate of 1.4 W/kg and a frequency of 2100 MHz positioned at a distance of 12 cm in the incubator for 60 min/night for 14 days. The histopathological examination involved hematoxylin and eosin staining, whereas cresyl violet staining was used to evaluate the condition and number of neurons in the brain. The biochemical parameters of amniotic fluid were analysed using the photometry method, and the expression of VEGF-A and immunity genes (AvBD9, IL6) was measured using the real-time PCR (qPCR) technique.

Results: Compared to the control, the exposure group's body weight and length significantly decreased (p < 0.05). Subcutaneous bleeding was seen in the exposure group. Urea, creatinine, alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase levels were all significantly higher than in the control group (p < 0.05). The exposed group showed pathological lesions in the liver and degenerated neurons with lightly stained nuclei in the cerebral cortex. Hyperchromatic neurons were significantly higher in the exposure group (58.8 ± 2.28) compared to the control (6.6 ± 0.44) (p < 0.05). 4G exposure reduced lymphocyte count in the caecal tonsil (86.8 ± 5.38) compared to the control (147.2 ± 9.06) (p < 0.05). Vascular gene mRNA expression was higher, but immune gene expression was lower in the exposed group.

Conclusion: Exposure to mobile phone radiation may result in gross, microscopic and biochemical changes, as well as alterations in gene expression that could hinder embryonic development.


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The potential protective effects of melatonin and omega-3 on the male rat optic nerve exposed to 900 MHz electromagnetic radiation during the prenatal period

Tüfekci KK, Kaplan AA, Kaya A, Alrafiah A, Altun G, Aktaş A, Kaplan S. The potential protective effects of melatonin and omega-3 on the male rat optic nerve exposed to 900 MHz electromagnetic radiation during the prenatal period. Int J Neurosci. 2023 Sep 15:1-15. doi: 10.1080/00207454.2023.2259078.

Abstract

Background: Due to children and adolescents' widespread use of electronic devices, researchers have focused on pre-and early postnatal electromagnetic field (EMF) exposure. However, little is known about the effects of EMF exposure on the optic nerve. The aim of study was to investigate the changes occurring in the optic nerve and the protective effects of melatonin (mel) and omega 3 (ω-3) in rats.

Methods: Thirty-five pregnant rats were divided into seven groups, Cont, Sham, EMF, EMF + melatonin (EMF + Mel), EMF + ω3, Mel, and ω3. The EMF groups were exposed to 900 megahertz (MHz) EMF daily for two hours during pregnancy. After the experiment, the right optic nerve of each offspring rat was removed and fixed in glutaraldehyde. Thin and semi-thin sections were taken for electron microscopic and stereological analyses. Myelinated axon numbers, myelin sheath thicknesses, and axonal areas were estimated using stereological methods.

Results: The groups had no significant differences regarding mean numbers of axons, mean axonal areas, or mean myelin sheath thicknesses (p > 0.05). Histological observations revealed impaired lamellae in the myelin sheath of most axons, and vacuolization was frequently observed between the myelin sheath and axon in the EMF-exposed group. The Mel and ω-3-treated EMF groups exhibited well-preserved myelinated nerve fibers and intact astrocytes and oligodendrocytes.

Conclusions: At the ultrastructural level, Mel and ω3 exhibit a neuroprotective effect on the optic nerve exposed to prenatal EMF. The protective effects of these antioxidants on oligodendrocytes, which play an essential role in myelin formation in the central nervous system, now require detailed investigation.


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Brain-implanted conductors amplify radiofrequency fields in rodents: Advantages and risks

Vöröslakos M, Yaghmazadeh O, Alon L, Sodickson DK, Buzsáki G. Brain-implanted conductors amplify radiofrequency fields in rodents: Advantages and risks. Bioelectromagnetics. 2023 Oct 24. doi: 10.1002/bem.22489.

Abstract

Over the past few decades, daily exposure to radiofrequency (RF) fields has been increasing due to the rapid development of wireless and medical imaging technologies. Under extreme circumstances, exposure to very strong RF energy can lead to heating of body tissue, even resulting in tissue injury. The presence of implanted devices, moreover, can amplify RF effects on surrounding tissue. Therefore, it is important to understand the interactions of RF fields with tissue in the presence of implants, in order to establish appropriate wireless safety protocols, and also to extend the benefits of medical imaging to increasing numbers of people with implanted medical devices. This study explored the neurological effects of RF exposure in rodents implanted with neuronal recording electrodes. We exposed freely moving and anesthetized rats and mice to 950 MHz RF energy while monitoring their brain activity, temperature, and behavior. We found that RF exposure could induce fast onset firing of single neurons without heat injury. In addition, brain implants enhanced the effect of RF stimulation resulting in reversible behavioral changes. Using an optical temperature measurement system, we found greater than tenfold increase in brain temperature in the vicinity of the implant. On the one hand, our results underline the importance of careful safety assessment for brain-implanted devices, but on the other hand, we also show that metal implants may be used for neurostimulation if brain temperature can be kept within safe limits.


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Protective effect of paricalcitol in rat testicular damage induced by subchronic 1800 MHz radiofrequency radiation

Demirbağ B, Aktaş S, Çömelekoğlu Ü, Kara İ, Yildirim M, Yildirim DD. Protective effect of paricalcitol in rat testicular damage induced by subchronic 1800 MHz radiofrequency radiation. Biochem Biophys Res Commun. 2023 Sep 12;680:42-50. doi: 10.1016/j.bbrc.2023.09.024.

Highlights

• RFR can damage testicular tissue.
• RFR-induced testis damage may be associated with subfertility and/or infertility.
• Paricalcitol decreased lipid peroxidation and increased antioxidant enzyme levels in tissue with RFR exposure.
• Paricalcitol has a protective role in testicular tissue against the damaging effect of RFR.

Abstract

In the present study, the possible protective effects of paricalcitol (P) were investigated in testicular damage because of 1800 MHz radiofrequency radiation (RFR) exposure. Male Sprague Dawley rats 8-10 weeks old (n = 28) were randomly divided into four groups as control (C) (n = 7), RFR (n = 7, 1800 MHz RFR 1 h/day for 30 days), P (n = 7, 0.2 μg/kg paricalcitol, 3 times a week for 30 days), and RFR + P (n = 7, 1800 MHz RFR 1 h/day for 30 days +0.2 μg/kg paricalcitol, 3 times a week for 30 days). Testicular tissue was evaluated with histological and biochemical methods. No statistically significant differences were detected between the groups in seminiferous tubule diameters and germinal epithelial thicknesses. While ultrastructural changes were observed in the seminiferous tubule and Leydig cells in the RFR group, these changes were decreased in the RFR + P group. It was found that the Johnsen Score, Ki67, and p63 immunoreactivity scores (IRS), superoxide dismutase (SOD), and catalase (CAT) activities in the RFR + P group were statistically increased as compared to the RFR group and the malondialdehyde (MDA) levels were decreased statistically and significantly. These results show that paricalcitol administration may have an ameliorative effect on testicular damage occurring because of 1800 MHz RFR exposure.

https://pubmed.ncbi.nlm.nih.gov/37717340/

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Inhibition of mitochondrial calcium uptake by Ru360 enhances the effect of 1800 MHz radio-frequency electromagnetic fields on DNA damage

Sun C, Zhu L, Qin H, Su H, Zhang J, Wang S, Xu X, Zhao Z, Mao G, Chen J. Inhibition of mitochondrial calcium uptake by Ru360 enhances the effect of 1800 MHz radio-frequency electromagnetic fields on DNA damage. Ecotoxicol Environ Saf. 2023 Sep 14;264:115472. doi: 10.1016/j.ecoenv.2023.115472.

Highlights
  • Ru360, a specific inhibitor of MCU, enhanced the DNA damage effect of short-time (15 min) exposure to1800 MHz RF-EMF
  • ATP synthesis play a role in cellular resistance to 1800 MHz RF-EMF short-time exposure on DNA damage.
  • DNA damage induced by 1800 MHz RF-EMF in Ru360 treated cells were quickly repaired within 1 h after exposure.
Abstract

Today, the existence of radio-frequency electromagnetic fields (RF-EMF) emitted from cell phones, wireless routers, base stations, and other sources are everywhere around our living environment, and the dose is increasing. RF-EMF have been reported to be cytotoxic and supposed to be a risk factor for various human diseases, thus, more attention is necessary. In recent years, interfere with mitochondrial calcium uptake by using mitochondrial calcium uniporter (MCU) inhibitor were suggested to be potential clinical treatment in mitochondrial calcium overload diseases, like neurodegeneration, ischemia/reperfusion injury, and cancer, but whether this approach increases the health risk of RF-EMF exposure are unknown. To address our concern, we did a preliminary study to determine whether inhibition of MCU will increase the genotoxicity of RF-EMF exposure in cells, and found that short-time (15 min) exposure to 1800 MHz RF-EMF induced significant DNA damage and cell apoptosis in mouse embryonic fibroblasts (MEFs) treated with Ruthenium 360 (Ru360), a specific inhibitor of MCU, but no significant effects on cell cycle, cell proliferation, or cell viability were observed. In conclusion, our results indicated that inhibiting MCU increases the genotoxicity of RF-EMF exposure, and more attention needs to be paid to the possible health impact of RF-EMF exposure under these treatments.


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Panax ginseng supplementation protects against testicular damage induced by radiofrequency electromagnetic radiation from cell phone

Oyewopo AO, Badejogbin OC, Ajadi IO et al. Panax ginseng supplementation protects against testicular damage induced by radiofrequency electromagnetic radiation from cell phone. Nutrire 48, 47 (2023). https://doi.org/10.1186/s41110-023-00234-7

Abstract

Purpose  It is well-documented that radiofrequency electromagnetic radiation (RF-EMR) from the cell phone contributes to testicular dysfunction and subsequently predisposes individuals, especially male to infertility. Panax ginseng (P. ginseng) exerts antioxidant, antidiabetic, neuroprotective, and anti-inflammatory effects in biological systems. However, its protective role against reproductive dysfunction, including testiculopathy is unclear. The objective of this study was to examine the protective effects of P. ginseng extract on testicular damage induced by RF-EMR from cell phones in male Wistar rats.

Methods  Twenty adult male Wistar rats (120–150 g) were randomly divided into four groups of n = 5; Control group received vehicle (normal saline, po), P. ginseng group received 200 mg/kg of P. ginseng extract (po), RF-EMR group was exposed to 900MHz of radiation and RF-EMR + P. ginseng group was exposed to 900MHz of radiation and was concomitantly treated with 200 mg/kg of P. ginseng (po). The treatment was done daily for 56 days. The animals were sacrificed, and the biochemical/endocrine parameters and the histology of testes were evaluated.

Results  There was a significant decrease in spermatogonia, sperm count, sperm motility, and sperm morphology with decrease in progressivity in RF-EMR group compared with control. Likewise, a significant decrease was observed in serum-luteinizing hormone, testosterone and glutathione peroxidase with degeneration of germ cells and Leydig cells, and a distorted interstitium in RF-EMR group compared with control. However, the administration of P. ginseng attenuated these alterations.

Conclusion  The results of the present study suggest that supplementation with P. ginseng extract ameliorates testicular dysfunction associated with RF-EMR from cell phone by enhancement of antioxidant capacity.


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Violation of molecular structure of intracellular water as a possible cause of carcinogenesis and its suppression by microwave radiation(hypothesis)

Kalantaryan V, Martirosyan R, Babayan Y, Petrosyan V. Violation of molecular structure of intracellular water as a possible cause of carcinogenesis and its suppression by microwave radiation(hypothesis). Computational and Structural Biotechnology Journal. 21:3437-3442. 2023. doi: 10.1016/j.csbj.2023.06.013.

Abstract

The manuscript discusses a possible hypothesis about the transformation of healthy cells into cancer cells as a result of modification of the molecular structure of intracellular water from normal hexagonal to abnormal cubic phase (which may be caused by radiation, chemical, viral, mechanical and microbiological factors) and the possibility of returning to its original state under the influence of microwave radiation. The authors are not aware of any relevant experimental and theoretical support for this hypothesis in other literature.Our hypothesis is based on a completely unexpected experimental fact that we have received. It turned out that the radio spectra of cancer-affected tissues and the cubic phase of water are identical which confirms that these tissues really contain a cubic phase of water. It should be expected that the use of radiation of “therapeutic” frequencies may lead to regression of tumor growth. This assumption is based on another experimental fact confirming the possibility of the transition of the molecular structure of water from the cubic phase to the hexagonal phase (which is contained in healthy tissues) when irradiated with therapeutic frequencies.The conducted experiments demonstrate the real possibilities of structural-phase and spectral mutual transformations of the water medium under the influence of extremely low intensity flows of microwaves at “therapeutic” frequencies of 1000 MHz and 985 MHz or “pathologic” frequencies of 990 MHz and 51 GHz. The aim of this study was to experimentally verify a possible causal relationship between the violation of the molecular structure of intracellular water in healthy tissues and carcinogenesis.

Open access paper: https://www.sciencedirect.com/science/article/pii/S200103702300226X

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Estimation of the Specific Absorption Rate for a Honey bee Exposed to Radiofrequency Electromagnetic Fields from 2.5 to 100 GHz

Jeladze V, Thielens A, Nozadze T, Korkotadze G, Partsvania B, Zaridze R. Estimation of the Specific Absorption Rate for a Honey bee Exposed to Radiofrequency Electromagnetic Fields from 2.5 to 100 GHz. 2023 IEEE XXVIII International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED), Tbilisi, Georgia, 2023, pp. 180-185, doi: 10.1109/DIPED59408.2023.10269454.

Abstract

This paper presents a study of electromagnetic field (EMF) exposure of a honey bee at radio frequencies from 2.5 GHz to 100 GHz using numerical simulations based on the finite-difference time-domain (FDTD) technique. The main goal of our study was to estimate the Specific Absorption Rate (SAR) in honey bee tissues as a dosimetric aid to predict the possible adverse effects caused by EMF energy absorption. In this study, the insect is modeled as a 3-tissue heterogeneous dielectric object, and the Sim4Life EM-FDTD solver was used for EM simulations. The whole-body and brain tissue-averaged SAR values of a honeybee were determined for all considered frequencies and normalized on 1 mW/cm2 incident plane-wave power density. The obtained SAR values were also averaged over a volume of 1 milligram of tissue. The results showed that EMF energy absorption in insects depends on E-field polarization, frequency, and the insect’s body peculiarities.


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Interspecific differences in the behavioral response of ticks exposed to radiofrequency electromagnetic radiation

Baňas M, Šofranková L, Kurimský J, Pavlík M, Pikalík M, Majláthová V, Cimbala R, Pipová N, Wurfl L, Majláth I. Interspecific differences in the behavioral response of ticks exposed to radiofrequency electromagnetic radiation. Exp Appl Acarol. 2023 Oct 11. doi: 10.1007/s10493-023-00847-7.

Abstract

Artificial electromagnetic radiation is a new environmental factor that affects animals. Experiments with the effect of radio frequency electromagnetic radiation were focused on both vertebrates and invertebrates. Ticks showed a significant affinity to radiation. Our study is a continuation of this research and its aim was to monitor the effect of radiation on the behavior of four tick species: Ixodes ricinus, Dermacentor reticulatus, Dermacentor marginatus and Haemaphysalis inermis. In total 1,200 ticks, 300 of each species, were tested in modules allowing the choice of an exposed or shielded area. During the test, the ticks were exposed to electro-magnetic radiation of 900 MHz for 24 h. The position of the individuals was recorded and we evaluated the obtained data statistically. We observed a significant preference to the exposed area in both sexes of I. ricinus. Males of D. reticulatus and D. marginatus also showed an affinity to radiation, but not females of both species, nor females and males of H. inermis. The results of the study support the assumption that ticks perceive the electromagnetic field and the observed differences in their response have the potential to help understand the mechanism of perception.


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Comprehensive analysis of genotoxic effects & antioxidative defence mechanisms in plant test system exposed to 1800 MHz EMR: a root chromosomal aberration & FTIR spectroscopy approach

Sharma, S., Sharma, P., Bahel, S. et al. Comprehensive analysis of genotoxic effects and antioxidative defence mechanisms in plant test system exposed to 1800 MHz electromagnetic radiations: a root chromosomal aberration and FTIR spectroscopy approach. Toxicol. Environ. Health Sci. (2023). doi: 10.1007/s13530-023-00190-9

Abstract

Objective  The proliferation of wireless communication devices has increased the exposure of living organisms to electromagnetic field radiations (EMF-rs), posing potential risks to various biological systems. The present study was planned to explore the genotoxic effects and oxidative stress responses of 1800 MHz electromagnetic radiations in Trigonella foenum-graecum L. plant test system. The study also pertained to assess the changes in functional groups using Fourier transform infrared spectroscopy (FTIR).

Methods  Twenty seeds of Trigonella foenum-graecum L. were placed in Petri plates lined with autoclaved Whatman No. 1 filter paper. The seeds were evenly distributed and maintained at temperature 25 ± 2 °C and relative humidity 55–60%. The seeds were placed in Petri plates along with the exposure apparatus (antenna) and then enclosed within a chamber consisting of two layers of aluminium sheets. The treatment was administered every day for seven days on various parameters.

Results  The investigation showed that increasing the duration of EMR exposure significantly decreased protein content and increased MDA content in seedlings. However, exposure to EMRs for 4 and 8 h per day led to increased activities of different antioxidant enzymes, including guaiacol peroxidase (POD), glutathione-S-transferase (GST), ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and superoxide dismutase (SOD). The study also calculated the specific absorption rate using the biological heat transfer equation, which revealed harmful effects of the radiations on the test system by interfering with biochemical processes, leading to genotoxic and oxidative stress.

Conclusion The findings suggest that electromagnetic radiations induced oxidative stress in T. foenum-graecum L. and increased activity of antioxidant enzymes as a protective mechanism against cellular damage. The study highlights the potential risks associated with EMF radiations on plant systems and underscores the importance of further research in this field.

Conclusions

The current study revealed that exposure to non-ionizing electromagnetic radiations at 1800 MHz caused genotoxic effects and oxidative stress in Trigonella foenum-graecum L. plant system. The outcomes of the present work indicated that exposure to EMRs of 1800 MHz led to reduced root and shoot length, as well as decreased fresh weight and protein content. The elevated levels of MDA content, a marker of oxidative stress, indicated that EMRs have induced oxidative damage in the plant test system. Furthermore, the present investigation has further shown that the plant has responded to the stress caused by EMRs by increasing their antioxidant defences. Hence, it can be revealed that EMRs at 1800 MHz can cause harmful effects in the living system, and therefore, it is mandatory to reduce the exposure risks in living beings to these non-ionizing radiations in order to avoid the ill health effects. This may include limiting the usage of electronic devices that emit EMRs, such as cell phones and Wi-Fi routers, and taking measures to reduce exposure to other sources of EMRs. By taking such precautions, it is possible to reduce the potential health risks allied with exposure to non-ionizing EMRs.


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Changes in rat spatial learning and memory as well as serum exosome proteins after simultaneous exposure to 1.5 GHz and 4.3 GHz microwaves

Wang H, Liu Y, Sun Y, Zhao L, Dong J, Xu X, Wang H, Zhang J, Yao B, Zhao X, Liu S, Zhang K, Peng R. Changes in rat spatial learning and memory as well as serum exosome proteins after simultaneous exposure to 1.5 GHz and 4.3 GHz microwaves. Ecotoxicol Environ Saf. 2022 Sep 15;243:113983. doi: 10.1016/j.ecoenv.2022.113983.

Abstract

This study aimed to elucidate the effects and biological targets sensitive to simultaneous 1.5 and 4.3 GHz microwave exposure in rats. A total of 120 male Wistar rats were divided randomly into four groups: the sham (S group), 1.5 GHz microwave exposure (L group), 4.3 GHz microwave exposure (C group) and simultaneous 1.5 and 4.3 GHz microwave exposure (LC group) groups. Spatial learning and memory, cortical electrical activity, and hippocampal ultrastructure were assessed by the Morris Water Maze, electroencephalography, and transmission electron microscopy, respectively. Additionally, serum exosomes were isolated by ultracentrifugation and assessed by Western blotting, nanoparticle tracking and transmission electron microscopy. The serum exosome protein content was assessed by label-free quantitative proteomics. Impaired spatial learning and memory decreased cortical excitability, and damage to the hippocampal ultrastructure were observed in groups exposed to microwaves, especially the L and LC groups. A total of 54, 145 and 296 exosomal proteins were differentially expressed between the S group and the L, C and LC groups, respectively. These differentially expressed proteins were involved in the synaptic vesicle cycle and SNARE interactions during vesicular transport. Additionally, VAMP8, Syn7 and VMAT are potential serum markers of simultaneous microwave exposure. Thus, exposure to 1.5 and 4.3 GHz microwaves induced impairments in spatial learning and memory, and simultaneous microwave exposure had the most severe effects.

Excerpts

... the 1.5 GHz microwave exposure group subjected to microwave exposure at an average power density of 10 mW/cm2 for 6 min (L group); the 4.3 GHz microwave exposure group subjected to microwave exposure at an average power density of 10 mW/cm2 for 6 min (C group); and the 1.5 GHz and 4.3 GHz microwave exposure group subjected to simultaneous microwave exposure at 10 mW/cm2 for 6 min (LC group)....

For a typical 230-g rat, the SARs were as follows: 3.3 W/kg, 2.5 W/kg, and 5.8 W/kg in the L, C, and LC groups, respectively....

In summary, exposure to a single microwave frequency (1.5 GHz, 10 mW/cm2 for 6 min) and multiple microwave frequencies (1.5 GHz and 4.3 GHz, 10 mW/cm2 for 6 min) impaired spatial learning and memory, induced EEG abnormalities, and damaged the hippocampal ultrastructure in rats. Simultaneous exposure to multiple microwave frequencies induced more severe impairments than exposure to a single microwave frequency. VAMP8, Syn7, and VMAT might be key molecules underlying the cognitive impairments caused by exposure to simultaneous microwave radiation.


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Parameter variation effects on millimeter wave dosimetry based on precise skin thickness in real rats

Li K, Hikage T, Masuda H, Ijima E, Nagai A, Taguchi K. Parameter variation effects on millimeter wave dosimetry based on precise skin thickness in real rats. Sci Rep. 2023 Oct 13;13(1):17397. doi: 10.1038/s41598-023-44572-y.

Abstract

This study presents a parametric analysis of the steady-state temperature elevation in rat skin models due to millimeter wave exposure at frequencies from 6-100 GHz. The statistical data of the thickness of skin layers, namely epidermis, dermis, dermal white adipose tissue, and panniculus carnosus, were measured for the first time using the excised tissues of real male Sprague-Dawley rats. Based on the precise structure obtained from the histological analysis of rat skin, we solve the bioheat transfer equation to investigate the effects of changes in parameters, such as body parts and thermal constants, on the absorbed power density and temperature elevation of biological tissues. Owing to the notably thin dermal white adipose tissue layer, the surface temperature elevation in the rat head and dorsal skin at 6-100 GHz is 52.6-32.3% and 83.3-58.8% of the average values of different human skin models, respectively. Our results also reveal that the surface temperature elevation of rat skin may correlate with the tissue thickness and deep blood perfusion rates.


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Long-term radiofrequency electromagnetic fields exposure attenuates cognitive dysfunction in 5×FAD mice by regulating microglial function

Son Y, Park HJ, Jeong YJ, Choi HD, Kim N, Lee HJ. Long-term radiofrequency electromagnetic fields exposure attenuates cognitive dysfunction in 5×FAD mice by regulating microglial function. Neural Regen Res. 2023 Nov;18(11):2497-2503. doi: 10.4103/1673-5374.371379.

Abstract

We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5×FAD mice with severe late-stage Alzheimer's disease reduced both amyloid-β deposition and glial activation, including microglia. To examine whether this therapeutic effect is due to the regulation of activated microglia, we analyzed microglial gene expression profiles and the existence of microglia in the brain in this study. 5×FAD mice at the age of 1.5 months were assigned to sham- and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months. We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/amyloid-beta metabolism in brain tissue. We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-β deposition. The expression levels of Iba1 (pan-microglial marker) and colony-stimulating factor 1 receptor (CSF1R; regulates microglial proliferation) in the hippocampus in 5×FAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group. Subsequently, we analyzed the expression levels of genes related to microgliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor (PLX3397)-treated group. Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis (Csf1r, CD68, and Ccl6) and pro-inflammatory cytokine interleukin-1β. Notably, the expression levels of genes related to microglial function, including Trem2, Fcgr1a, Ctss, and Spi1, were decreased after long-term radiofrequency electromagnetic field exposure, which was also observed in response to microglial suppression by PLX3397. These results showed that radiofrequency electromagnetic fields ameliorated amyloid-β pathology and cognitive impairment by suppressing amyloid-β deposition-induced microgliosis and their key regulator, CSF1R.


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Commentary: Mobile cell phone use and impact on male fertility potential: an environmental pollutant that needs more research

Chu KY, Petrella F, Bidhan J. Commentary: Mobile cell phone use and impact on male fertility potential: an environmental pollutant that needs more research. Fertil Steril. 2023 Oct 13:S0015-0282(23)01941-6. doi: 10.1016/j.fertnstert.2023.10.019.

No abstract.


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A microfabricated lab-on-chip with three-dimensional electrodes for microscopic observation of bioelectromagnetic effects of cells

Lu Y, Shi Y. A microfabricated lab-on-chip with three-dimensional electrodes for microscopic observation of bioelectromagnetic effects of cells. Bioelectrochemistry. 2023 Dec;154:108554. doi: 10.1016/j.bioelechem.2023.108554.

Abstract

Electromagnetic (EM) signals are widely used in electronic instruments and biomedical systems and might have affected the human bodies surrounded by them. However, the interaction mechanism of EM signals with biological structures is poorly understood. We propose a micro-fabricated low-frequency EM stimulation lab-on-chip with three-dimensional interdigital electrodes for observation of cell lines with microscope. The field strength between the electrodes at various frequencies is estimated through simulation. An electric field strength of 4.45Vrms/m is reached in the culture medium with a 10Vpp, 10 kHz input signal. According to the simulation results, the high end of the applicable frequency range of the testbench is 3 MHz. A prototype is fabricated using full-wafer microfabrication techniques. The impedance of the prototype between 20 Hz and 30 MHz is characterized. Moreover, human cell line HEK293T is cultured in the testbench for 24 h and observed using microscope to check the biocompatibility of the electrodes. The prototype is thus applicable to long-term microscopic observation of cell lines for study of EM effect on biological structures. The 24-h cell culturing experiment with and without EM stimulation with the proposed prototype shows that the cell growth is obviously affected by a 10 kHz EM signal.


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Extremely low-frequency electromagnetic field induces acetylation of heat shock proteins and enhances protein folding

Huang Z, Ito M, Zhang S, Toda T, Takeda JI, Ogi T, Ohno K. Extremely low-frequency electromagnetic field induces acetylation of heat shock proteins and enhances protein folding. Ecotoxicol Environ Saf. 2023 Sep 15;264:115482. doi: 10.1016/j.ecoenv.2023.115482.

Highlights

• We previously showed that ELF-EMF at 10 µT induces mitochondrial hormesis.
• In AML12 and HEK293 cells, ELF-EMF markedly increased acetylation of HSP70/90 at 3 h.
• In both cells, ELF-EMF markedly increased binding of HSP70/90 to HOP/STIP1 at 3 h.
• In both cells, ELF-EMF reduced protein aggregates and enhanced cell viability at 3 h.
• In both cells, ELF-EMF reduced mitochondria mass and elevated maximal oxygen consumption at 3 h.

Abstract

The pervasive weak electromagnetic fields (EMF) inundate the industrialized society, but the biological effects of EMF as weak as 10 µT have been scarcely analyzed. Heat shock proteins (HSPs) are molecular chaperones that mediate a sequential stress response. HSP70 and HSP90 provide cells under undesirable situations with either assisting covalent folding of proteins or degrading improperly folded proteins in an ATP-dependent manner. Here we examined the effect of extremely low-frequency (ELF)-EMF on AML12 and HEK293 cells. Although the protein expression levels of HSP70 and HSP90 were reduced after an exposure to ELF-EMF for 3 h, acetylations of HSP70 and HSP90 were increased, which was followed by an enhanced binding affinities of HSP70 and HSP90 for HSP70/HSP90-organizing protein (HOP/STIP1). After 3 h exposure to ELF-EMF, the amount of mitochondria was reduced but the ATP level and the maximal mitochondrial oxygen consumption were increased, which was followed by the reduced protein aggregates and the increased cell viability. Thus, ELF-EMF exposure for 3 h activated acetylation of HSPs to enhance protein folding, which was returned to the basal level at 12 h. The proteostatic effects of ELF-EMF will be able to be applied to treat pathological states in humans.


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Study on the safety assessment and protection design of human exposure to low-frequency magnetic fields in electric vehicles

Tan L, Li G, Xie Q, Xiang Y, Luo B. Study on the safety assessment and protection design of human exposure to low-frequency magnetic fields in electric vehicles. Radiat Prot Dosimetry. 2023 Oct 10:ncad269. doi: 10.1093/rpd/ncad269

Abstract

As the power performance of electric vehicles continues to improve, the human body may be exposed to electromagnetic threats in the cabin. This study tested an electric vehicle to analyze the low-frequency magnetic field distribution in the cabin and to assess the safety of human low-frequency magnetic field exposure. A simulation analysis of human electromagnetic exposure was carried out to obtain the magnetic flux density, induced electric field strength and induced current density, and the test results were much lower than the limits specified in GB8702-2014 and the International Commission on Non-Ionizing Radiation Protection, and the relative error between the simulation results and the test results was <15%. This paper investigates the frequency, driving current, vehicle body material and cable layout to explore the law of human body induced electromagnetic field changing with power cable current, and provides theoretical reference for the design of human body low-frequency magnetic field protection.

Excerpt

"All positions of the electric vehicle magnetic flux density test data are less than the GB8702-2014 and ICNIRP provisions of the public exposure limits through the safety assessment, but the minimum margin value should be strengthened to protect the position to ensure full safety of human low-frequency magnetic field exposure."


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The European Union assessments of radiofrequency radiation health risks – another hard nut to crack (Review)

Nyberg R, McCredden J, Hardell L. The European Union assessments of radiofrequency radiation health risks – another hard nut to crack (Review). Reviews on Environmental Health. 2023. doi: 10.1515/reveh-2023-0046.

Abstract

In 2017 an article was published on the unwillingness of the WHO to acknowledge the health effects associated with the use of wireless phones. It was thus stated that the WHO is ‘A Hard Nut to Crack’. Since then, there has been no progress, and history seems to be repeating in that the European Union (EU) is following in the blind man’s footsteps created by the WHO. Despite increasing evidence of serious negative effects from radiofrequency radiation on human health and the environment, the EU has not acknowledged that there are any risks. Since September 2017, seven appeals by scientists and medical doctors have been sent to the EU requesting a halt to the roll-out of the fifth generation of wireless communication (5G). The millimeter waves (MMW) and complex waveforms of 5G contribute massively harmful additions to existing planetary electromagnetic pollution. Fundamental rights and EU primary law make it mandatory for the EU to protect the population, especially children, from all kinds of harmful health effects of wireless technology. However, several experts associated with the WHO and the EU have conflicts of interest due to their ties to industry. The subsequent prioritizing of economic interests is resulting in human and planetary health being compromised. Experts must make an unbiased evaluation with no conflicts of interest. The seven appeals to the EU have included requests for immediate protective action, which have been ignored. On the issue of wireless radiation and the health of citizens, the EU seems to be another hard nut to crack.
Section headings
  • Introduction
  • ICNIRP guidelines are an inadequate basis for EU policy
  • Evidence of harm from wireless EMF provided to EU
  • Complex real-world exposures not addressed by ICNIRP
  • 5G science consistent with previous wireless EMF science, warning the EU of harm
  • Conflicts of interests in ICNIRP and SCENIHR
  • SCHEER is misleading EU
  • EU is condoning an unethical mass experiment
  • Safe, energy efficient alternatives exist
  • Smart utility meters need to be wired
  • EU Green Deal compromised by wireless deployment
  • Fundamental rights, new policy needed
  • Towards a health protective and energy saving EU policy
  • Concluding remarks
"In 2017 an article was published on the lack of WHO willingness to acknowledge health effects from use of wireless phones. It was stated that WHO is a hard nut to crack [69]. This statement now seems to be true of the EU. In spite of being provided with increasing evidence of the negative effects on human health, no measures have been taken to reduce exposure or to educate people on the risks. On the contrary, ambient exposure has increased [103]. Protests and comments by scientific experts and several organisations including non-governmental organization (NGOs) have been ignored. Instead, the EU has heeded only the opinions of a handful of experts, associated with WHO, ICNIRP, and SCHEER, with conflicts of interest due to ties with industry. Therefore, any opinion these “experts” may give on wireless EMF and human health is compromised. It is urgent that unbiased evaluations of risks be made by experts with no conflicts of interest. In spite of thousands of scientific reports proving harmful effects of wireless EMF, all seven appeals sent to the EU since 2017 have been neglected. These reviews have requested immediate action from the EU on its mandated responsibilities; i.e., to protect humans and the environment instead of promoting industry interests."


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My note: The following paper (SR4: Adverse reproductive outcomes (animal and in vitro studies)), the first of ten systematic reviews commissioned by the World Health Organization (WHO), was published online in a forthcoming special issue, "WHO assessment of health effects of exposure to radiofrequency electromagnetic fields: systematic reviews," of the journal Environment InternationalThese reviews will form the basis of a forthcoming WHO publication: Environmental Health Criteria (EHC) Monograph on Radio Frequency (RF) Fields and Health RisksFor more information about the monograph see https://bit.ly/WHOicnirp.

Effects of Radiofrequency Electromagnetic Field (RF-EMF) exposure on pregnancy and birth outcomes: A systematic review of experimental studies on non-human mammals

Cordelli E, Ardoino L, Benassi B, Consales C, Eleuteri P, Marino C, Sciortino M, Villani P, Brinkworth MH, Chen G, McNamee JP, Wood AW, Belackova L, Verbeek J, Pacchierotti F. Effects of Radiofrequency Electromagnetic Field (RF-EMF) exposure on pregnancy and birth outcomes: A systematic review of experimental studies on non-human mammals, Environment International, 2023, doi: 10.1016/j.envint.2023.108178.

Abstract

Background  The World Health Organization is coordinating an international project aimed at systematically reviewing the evidence regarding the association between radiofrequency electromagnetic field (RF-EMF) exposure and adverse health effects. Within the project, 6 topics have been prioritized by an expert group, which include reproductive health outcomes.

Objectives  According to the protocol published in 2021, a systematic review and meta-analyses on the adverse effects of RF-EMF exposure during pregnancy in offspring of experimental animals were conducted.

Methods Three electronic databases (PubMed, Scopus and EMF Portal) were last searched on September 8 or 17, 2022. Based on predefined selection criteria, the obtained references were screened by two independent reviewers.

Studies were included if they met the following criteria:

1) original, sham controlled experimental study on non-human mammals exposed in utero, published in peer-reviewed journals, 
2) the experimental RF-EMF exposure was within the frequency range 100 kHz-300 GHz, 
3) the effects of RF-EMF exposure on fecundity (litter size, embryonic/fetal losses), on the offspring health at birth (decrease of weight or length, congenital malformations, changes of sex ratio) or on delayed effects (neurocognitive alterations, female infertility or early-onset cancer) were studied. 

Study characteristics and outcome data were extracted by two reviewers. Risk of bias (RoB) was assessed using the Office of Health Assessment and Translation (OHAT) guidelines. Study results were pooled in a random effects meta-analysis comparing average exposure to no-exposure and in a dose-response meta-analysis using all exposure doses, after exclusion of studies that were rated at “high concern” for RoB. Subgroup analyses were conducted for species, Specific Absorption Rate (SAR) and temperature increase. The certainty of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

Results

Eighty-eight papers could be included in this review. 

Effects on fecundity. The meta-analysis of studies on litter size, conducted at a whole-body average SAR of 4.92 W/kg, did not show an effect of RF-EMF exposure (MD 0.05; 95% CI -0.21 to 0.30). The meta-analysis of studies on resorbed and dead fetuses, conducted at a whole-body average SAR of 20.26 W/kg, showed a significant increase of the incidence in RF-EMF exposed animals (OR 1.84; 95% CI 1.27 to 2.66). The results were similar in the dose-response analysis. 

Effects on the offspring health at birth. The meta-analysis of studies on fetal weight, conducted at a whole-body average SAR of 9.83 W/kg, showed a small decrease in RF-EMF exposed animals (SMD 0.31; 95% CI 0.15 to 0.48). The meta-analysis of studies on fetal length, conducted at a whole-body average SAR of 4.55 W/kg, showed a moderate decrease in length at birth (SMD 0.45; 95% CI 0.07 to 0.83). The meta-analysis of studies on the percentage of fetuses with malformations, conducted at a whole-body average SAR of 6.75 W/kg, showed a moderate increase in RF-EMF exposed animals (SMD -0.45; 95% CI -0.68 to -0.23). The meta-analysis of studies on the incidence of litters with malformed fetuses, conducted at a whole-body average SAR of 16.63 W/kg, showed a statistically significant detrimental RF-EMF effect (OR 3.22; 95% CI 1.9 to 5.46). The results were similar in the dose-response analyses. 

Delayed effects on the offspring health. RF-EMF exposure was not associated with detrimental effects on brain weight (SMD 0.10, 95% CI -0.09 to 0.29) and on learning and memory functions (SMD -0.54, 95% CI -1.24 to 0.17). RF-EMF exposure was associated with a large detrimental effect on motor activity functions (SMD 0.79, 95% CI 0.21 to 1.38) and a moderate detrimental effect on motor and sensory functions (SMD -0.66, 95% CI -1.18 to -0.14). RF-EMF exposure was not associated with a decrease of the size of litters conceived by F2 female offspring (SMD 0.08, 95% CI -0.39 to 0.55). Notably, meta-analyses of neurobehavioural effects were based on few studies, which suffered of lack of independent replication deriving from only few laboratories.

Discussion  

There was high certainty in the evidence for a lack of association of RF-EMF exposure with litter size. We attributed a moderate certainty to the evidence of a small detrimental effect on fetal weight. We also attributed a moderate certainty to the evidence of a lack of delayed effects on the offspring brain weight. For most of the other endpoints assessed by the meta-analyses detrimental RF-EMF effects were shown, however the evidence was attributed a low or very low certainty. The body of evidence had limitations that did not allow an assessment of whether RF-EMF may affect pregnancy outcomes at exposure levels below those eliciting a well-known adverse heating impact. In conclusion, in utero RF-EMF exposure does not have a detrimental effect on fecundity and likely affects offspring health at birth, based on the meta-analysis of studies in experimental mammals on litter size and fetal weight, respectively. Regarding possible delayed effects of in utero exposure, RF-EMF probably does not affect offspring brain weight and may not decrease female offspring fertility; on the other hand, RF-EMF may have a detrimental impact on neurobehavioural functions, varying in magnitude for different endpoints, but these last findings are very uncertain. Further research is needed on the effects at birth and delayed effects with sample sizes adequate for detecting a small effect. Future studies should use standardized endpoints for testing prenatal developmental toxicity and developmental neurotoxicity (OECD TG 414 and 426), improve the description of the exposure system design and exposure conditions, conduct appropriate dosimetry characterization, blind endpoint analysis and include several exposure levels to better enable the assessment of a dose response relationship. 

Study selection

Figure 2 shows the flow diagram from the initially retrieved references to the finally included papers, as per the PRISMA 2020 template (Page et al., 2021). After exclusion of duplicate records and of papers deemed not eligible based on title/abstract, a total of 236 papers remained for full-text assessment; we could not retrieve 11 papers and were unable to translate 10 papers. Of the remaining 215 papers, we excluded 127 after reading the full text. Therefore, the systematic review is based on a total of 88 papers.

Implications for policy and research

This systematic review of animal studies shows that RF-EMF exposure does not affect fecundity and likely has only a small effect on fetal weight decrease. However, some studies retrieved by the literature search that showed a detrimental effect on the incidence of dead/resorbed fetuses or the increase of malformations at high exposure levels, largely exceeding the current human exposure limits, cannot be discounted. These studies confirm what is known about the harmful effect of heating on fetuses, but they leave largely uncertain the possibility of RF-EMF effects at lower exposure levels, closer to relevant human exposure levels. Currently, it remains difficult to determine the exposure levels at which RF-EMF can start to affect fecundity or offspring health at birth. The whole body average SAR values in the included experiments are well above the recommended human exposure limit values for the general public set by international bodies (ICNIRP 2020). Actual SAR values experienced by the public in the general environment are below, and in most cases, well below, the recommended human exposure limit values. The dose effect meta-analyses contributed to support the results of the meta-analysis but were not supposed to define the shape of the dose-effect relationship or find a minimum exposure level at which a clear effect could be discerned.

For two endpoints planned in the protocol, namely ano-genital distance at birth and early-onset cancer no studies were retrieved. Ano-genital distance is a well-known developmental biomarker associated with impairment of the reproductive system and exposure to environmental carcinogens during pregnancy have been linked with development of childhood cancer (Botsivali and Kyrtopoulos, 2019). Hopefully, future research will shed light on the impact of RF-EMF exposure on these outcomes.

As a whole, the possible impact of in utero RF-EMF exposure remains uncertain due to the severe limitations of some of the studies. In particular, during the systematic review, we identified several methodological limitations in the studies that should be overcome in future studies to improve the quality of the research. Blinding during experiment performance and outcome assessment should always be applied to minimize bias. More adherence to OECD Test Guideline 414 “Prenatal Developmental Toxicity study” and 426 “Developmental Neurotoxicity Study” is recommended together with a more standardized approach for reporting results. A large proportion of included studies was rated at either “some” or “high concern” for RoB for exposure characterisation or temperature rise assessment and some others had to be excluded from the systematic review because they did not reach a minimum quality standard for these aspects. We would recommend that future studies bear the reasons for exclusion or RoB concerns in mind in study design and implementation. There are several papers in the research literature with recommendations on how exposure characterisation concerns can be mitigated, for example Kuster and Schönborn (2000). Finally, studies investigating not just a single level but several exposure levels, spanning from low levels comparable to human exposure to higher levels where mild hyperthermic effects could be expected, should be conducted under the same experimental conditions.

In spite of the large number of studies collected, our systematic review could only partly answer the PECO question and did not provide conclusions certain enough to inform decisions at a regulatory level, but it can be considered a solid starting point to direct future research on this topic.

Open access paper: https://www.sciencedirect.com/science/article/pii/S0160412023004518