Tuesday, September 19, 2023

Does exposure to 4G LTE cell phone radiation impair cell phone users' health?

Although 4G has been in use for over a decade and far more people in the world are currently exposed to 4G mobile phone radiation than 5G, little attention has been paid to the potential harmful health effects of this environmental pollutant.

4G, 
also known as Long Term Evolution or LTE, is the fourth generation of cellular technology. It employs new digital signal processing and modulation to increase the capacity and speed of wireless telecommunications networks. 

The standard for LTE was finalized in December, 2008, and the first mobile phone to employ this technology was released in September 2010. By the end of 2017, 41 countries supported LTE coverage over at least 75% of their land area. In North America, the number of LTE mobile devices in use, 365 million, exceeded the size of the population. By 2021, 70 countries had LTE coverage available to at least 75% of the population.

Like 5G, LTE was launched without any pre-market safety testing. Research has found that exposure to LTE radiation leads to a change in intracellular reactive oxygen species (ROS) that may result in "genotoxic stress, decreased proliferation and cell senescence, or no physiological effects depending on ROS concentration and the differential sensitivity of various cells to ROS." Several studies on human subjects have found that short-term exposure to LTE radiation affects brain functioning. No research has examined the health effects of long-term exposure to LTE.

Although 4G technology has been in use for more than a decade, few studies have been conducted on the effects of exposure. The abstracts for these studies appear below.

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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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Exposure to 1800 MHz LTE electromagnetic fields under proinflammatory conditions decreases the response strength and increases the acoustic threshold of auditory cortical neurons

Samira Souffi, Julie Lameth, Quentin Gaucher, Délia Arnaud-Cormos, Philippe Lévêque, Jean-Marc Edeline, Michel Mallat. Exposure to 1800 MHz LTE electromagnetic fields under proinflammatory conditions decreases the response strength and increases the acoustic threshold of auditory cortical neurons. Sci Rep. 2022 Mar 8;12(1):4063. doi: 10.1038/s41598-022-07923-9.

Abstract

Increased needs for mobile phone communications have raised successive generations (G) of wireless technologies, which could differentially affect biological systems. To test this, we exposed rats to single head-only exposure of a 4G long-term evolution (LTE)-1800 MHz electromagnetic field (EMF) for 2 h. We then assessed the impact on microglial space coverage and electrophysiological neuronal activity in the primary auditory cortex (ACx), under acute neuroinflammation induced by lipopolysaccharide. The mean specific absorption rate in the ACx was 0.5 W/kg. Multiunit recording revealed that LTE-EMF triggered reduction in the response strength to pure tones and to natural vocalizations, together with an increase in acoustic threshold in the low and medium frequencies. Iba1 immunohistochemistry showed no change in the area covered by microglia cell bodies and processes. In healthy rats, the same LTE-exposure induced no change in response strength and acoustic threshold. Our data indicate that acute neuroinflammation sensitizes neuronal responses to LTE-EMF, which leads to an altered processing of acoustic stimuli in the ACx.

Excerpt

In conclusion, our study reveals that a single head-only exposure to LTE-1800 MHz can interfere with the neuronal responses of cortical neurons to sensory stimuli. In line with previous characterizations of the effect of GSM-signal, our results show that the impact of LTE signal on neuronal activity varies according to the health state. Acute neuroinflammation sensitize neuronal responses to LTE-1800 MHz, resulting in altered cortical processing of auditory stimuli.


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The effect of 4.5 G (LTE Advanced-Pro network) mobile phone radiation 
on the optic nerve

Erkin Özdemir, Ülkü Çömelekoglu, Evren Degirmenci, Gülsen Bayrak, Metin Yildirim, Tolgay Ergenoglu, Banu Coşkun Yılmaz, Begüm Korunur Engiz, Serap Yalin, Dilan Deniz Koyuncu, Erkan Ozbay. The effect of 4.5 G (LTE Advanced-Pro network) mobile phone radiation on the optic nerve. Cutan Ocul Toxicol. 2021 Mar 3;1-27. doi: 10.1080/15569527.2021.1895825.

Abstract

Purpose: Rapid development in mobile phone technologies increase the average mobile phone usage duration. This increase also triggers exposure to radiofrequency radiation (RF), which is a risk factor for the health. In this study, it was aimed to investigate the effect of mobile phone working with LTE-Advanced Pro (4.5G) mobile network on the optic nerve, which is responsible for the transmission of visual information.

Material and methods: Thirty-two rats divided into two groups as control (no RF, sham exposure) and experimental (RF exposure using a mobile phone with LTE-Advanced Pro network; 2 hours/day, 6 weeks). The visual evoked potential (VEP) was recorded and determined amplitudes and latencies of VEP waves. Optic nerve malondialdehyde level, catalase and superoxide dismutase activities were determined. Furthermore, ultrastructural and morphometric changes of optic nerve were evaluated.

Results: In VEP recordings, the mean VEP amplitudes of experimental group were significantly lower than control group. In ultrastructural evaluation, myelinated nerve fibers and glial cells were observed in normal histologic appearance both in sham and experimental group. However, by performing morphometric analysis, in the experimental group, axonal diameter and myelin thickness were shown to be lower and the G-ratio was higher than in the sham group. In the experimental group, malondialdehyde level was significantly higher and superoxide dismutase and catalase activities were significantly lower than sham group. There was a high correlation between VEP wave amplitudes and oxidative stress markers.

Conclusion: Findings obtained in this study support optic nerve damage. These results point out an important risk that may decrease the quality of life.


Excerpts

In recent years, everyone, from child to old, has a smartphone, and everyday a long time is passed looking at the screen of this phone. Comfort and efficiency achieved thanks to the high data transfer rate provided by LTE-Advanced Pro technology increase this time day by day. Eyes are the most affected body parts from this condition. In addition to the effects such as strabismus and eye impairment arising from looking at a small screen, it is also important to examine the hidden risks that the RF magnetic field created by the phone will cause on the eye. In this study, the effects of RF emission created by a LTE-Advanced Pro technology phone on the optic nerve were examined in all aspects and the findings were given in the previous section. Briefly it can be said that, for the first time in scientific literature, the findings of the present study indicate that the LTE-Advanced Pro mobile phone radiation causes significant damage by triggering oxidative stress in the optic nerve. LTE-Advanced Pro technology uses a wider RF band between 800 MHz and 2600 MHz and the network system selects the most appropriate band itself according to the user’s requirements. It is known that penetration depth of RF increases with decreasing frequency [39]. Since effects of RF radiation were observed on the optic nerve which is behind the eye, it can be said that low frequency bands such as 800 MHz were mostly active during the experiments. Maybe this inference cannot be generalized for all communication purposes, but usage probability of low frequency bands during LTE-Advanced Pro smart phone usage will always keep the damage risk on optic nerve alive.

Fig. 3A and 3B show the distribution of electric field and SAR, respectively. As seen, maximum E field was 5.0 V/m (Fig. 3A) and maximum SAR (10 g) was 0.01 W/kg (Fig. 3B). The SAR value in the area of eyes was about 0.0035 W/kg (Fig. 3B).

Before and after exposure, body surface temperatures were 28.08 ± 0.19 and 28.07 ± 0.26 °C, respectively in the sham group. These values were 28.37 ± 0.29 and 28.39 ± 0.22 °C, respectively for the RF groups. There was no significant difference within sham (p = 0.275) and RF (p = 0.120) groups before and after exposure. Also, there was no significant differences in surface body temperature between sham and RF exposed groups before (p = 0.142) and after (p = 0.321) exposure.

In the present study, for the first time, it was shown that exposition to 4.5 G mobile phone radiation for 2 hours/day for 6 weeks causes optic nerve damage. The optic nerve transmits all visual information to the visual cortex, and any damage in this nerve can cause permanent and serious vision loss. This study demonstrated that RF exposure may be an environmental risk factor for eye toxicity and potential eye disorders. Further studies are needed to reveal the potentiality of the risk in this area.  

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Hematobiochemical and histopathological alterations of kidney and testis 
due to exposure of 4G cell phone radiation in mice

Imam Hasan, Tanjina Amin, Md. Rafiqul Alam, Mohammad Rafiqul Islam. Hematobiochemical and histopathological alterations of kidney and testis due to exposure of 4G cell phone radiation in mice. Saudi Journal of Biological Sciences. Available online 17 February 2021. https://doi.org/10.1016/j.sjbs.2021.02.028.

Abstract

The radiofrequency electromagnetic radiation emitted by smart phones on biological systems has wide media coverage and public concern in recent years. The aim of this study was to explore the effects of fourth-generation cell phone radiation exposure on hematological (Total leukocyte count, Total erythrocyte count, and hemoglobin %), biochemical (Serum creatinine) parameters, and histopathological changes in the kidney and testis of Swiss albino mice. A total of 30 male Swiss albino mice weighing 45–65 g was randomly divided into three groups (n = 10). The first group A was the control group, the second group B, was exposed to 40 minutes of mobile phone radiation daily, the third group C was exposed to 60 minutes of radiation daily from two 2400 Megahertz fourth-generation connected mobile phones for 60 days, respectively. The electromagnetic radiation frequency radiometer measured the frequency of electromagnetic radiation emitted from cell phones. The specific absorption rate was calculated as 0.087 W/kg. The control group was kept under similar conditions, but the electromagnetic field was not given for the same period. All the mice were sacrificed at the end of the experiment. The blood samples were collected for hematobiochemical study, and then kidney and testis tissues were collected for histopathological study. Results of the study showed that the body weight and total erythrocyte count values were significantly (p < 0.05) decreased while total leukocyte count, hemoglobin %, and serum creatinine values were significantly (p < 0.05) increased in both the radiation exposure groups relative to the control group. Histopathological observation showed the kidney of 60 minutes exposed mice interstitial inflammation that causes marked mononuclear cellular infiltration compared to the 40 minutes and control mice. Compared to control mice, histopathological examinations of testicular tissue from the exposed mice, showed irregular in shapes and non-uniform sizes and fewer spermatogenic cells layer that leads to the larger lumen in the seminiferous tubules. It is concluded that fourth-generation cell phone radiation exposure may affect blood hemostasis and inflammation of mice's kidney and testis tissue. Based on these studies, it is important to increase public consciousness of potential adverse effects of mobile phone radiofrequency electromagnetic radiation exposure.


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Empirical study on specific absorption rate of head tissues due to induced heating of 4G cell phone radiation

Christopher B, Mary S, Khandaker MU, Jojo PJ. Empirical study on specific absorption rate of head tissues due to induced heating of 4G cell phone radiation. Radiation Physics and Chemistry. 178(Special Issue): 108910. Jan 2021. DOI:10.1016/j.radphyschem.2020.108910.

Abstract

Exposures to electromagnetic radiation mainly from the extended use of mobile phones may initiate biological damages in the human body at the macromolecular level. Several studies on human and animal models have shown significant changes in the functions of neural cells. Present empirical study analyses the thermal changes and the specific absorption rates (SAR) of brain, eye and skin tissues due to prolonged exposure to mobile phone radiation. A phantom, simulating human head with skin, skull and brain was used for the study. The Phantom was exposed to radiation for longer durations (600 s and more) and the temperature variations at different specific points were studied with sensitive thermocouple probes. SAR (1 g of contiguous tissue) values were determined using the variations of temperature and other parameters. The average rise in brain temperature was found to be 0.10 +/- 0.05 degrees C at 30 mm deep in the brain and the estimated SAR was 0.66 +/- 0.35 Wkg(-1). The increase in temperature for the eye socket was 0.03 +/- 0.02 degrees C with SAR 0.15 +/- 0.08 Wkg(-1). The average rise in temperature for skin was 0.14 +/- 0.05 degrees C and the SAR was 0.66 +/- 0.42 Wkg(-1). Although the measured SAR lie within the safe limit of 2 Wkg(-1) recommended by the international regulatory body, considering the tremendous growth in the number of mobile phone users and prolonged use of mobile phone in communication purposes, the cumulative effects could be a real concern for human health.


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Functional and network analyses of human exposure to long-term evolution signal

Lei Yang, Chen Zhang, Zhiye Chen, Congsheng Li, Tongning Wu. Functional and network analyses of human exposure to long-term evolution signal. Environ Sci Pollut Res Int. 2020 Sep 25. doi: 10.1007/s11356-020-10728-w.

Abstract

Human exposure to the electromagnetic field emitted by wireless communication systems has raised public concerns. There were claims of the potential association of some neurophysiological disorders with the exposure, but the mechanism is yet to be established. The wireless networks, recently, experience a transition from the 4th generation (4G) to 5th generation (5G), while 4G long-term evolution (LTE) is still the frequently used signal in wireless communication. In the study, exposure experiments were conducted using the LTE signal. The subjects were divided into sham and real exposure groups. Before and after the exposure experiments, they underwent functional magnetic resonance imaging. Within-session and between-session comparisons have been executed for functional connectivity and network properties. Individual specific absorption rate (SAR) was also calculated. The results indicated that acute LTE exposure beneath the safety limits modulated both the functional connection and graph-based properties. To characterize the effect of functional activity, SAR averaged over a certain tissue mass was not an appropriate metric. The potential neurophysiological effect of 5G exposure has also been discussed in the study.

https://pubmed.ncbi.nlm.nih.gov/32974829/

Excerpts

Since 2019, the fifth-generation (5G) wireless network has been implemented. Two different frequency ranges available for 5G wireless technology include- frequency range 1 (FR1) and frequency range 2 (FR2). At present, the popular commercial frequency at FR1 was around 2.4 and 3.5 GHz, close to the current 3G and 4G frequencies. The emission power of 5G mobile phones is comparable to that of 3G and 4G terminals. Most of the existed literature, as well as our studies, narrated similar activated sites (frontal and temporal lobules) for different frequencies/modulations. It is, therefore, reasonable to expect that the exposure to new generation wireless signals would result in a similar effect.

Conclusion

Human brain modulation following LTE exposure was first evaluated by functional and network metrics. The topological changes have been reported, and their consistency with the previous analysis was highlighted. Integrating the results from the regional BOLD variation, intraregional similarity, and hypothesis-driven FC analysis, a comprehensive view for the brain activity by the exposure of LTE signal and the signal of next-generation can be obtained. Another novelty was that no correlation was found between the peak SAR values and the altered topological parameters. It demonstrated peak SAR averaged over a certain mass, which was used for assessing the thermal effect of human exposure, was incongruous to quantify the neurophysiological effect of EMF exposure. It may clarify the inconsistency in current human exposure studies.

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Continuous Exposure to 1.7 GHz LTE (4G) Electromagnetic Fields Increases Intracellular Reactive Oxygen Species to Decrease Human Cell Proliferation and Induce Senescence


Jisu Choi, Kyeongrae Min, Sangbong Jeon, Nam Kim, Jeong-Ki Pack, Kiwon Song. Continuous Exposure to 1.7 GHz LTE Electromagnetic Fields Increases Intracellular Reactive Oxygen Species to Decrease Human Cell Proliferation and Induce Senescence. Sci Rep. 2020 Jun 8;10(1):9238. doi: 10.1038/s41598-020-65732-4.

Abstract

Due to the rapid development of mobile phone technology, we are continuously exposed to 1.7 GHz LTE radio frequency electromagnetic fields (RF-EMFs), but their biological effects have not been clarified. Here, we investigated the non-thermal cellular effects of these RF-EMFs on human cells, including human adipose tissue-derived stem cells (ASCs), Huh7 and Hep3B liver cancer stem cells (CSCs), HeLa and SH-SY5Y cancer cells, and normal fibroblast IMR-90 cells. When continuously exposed to 1.7 GHz LTE RF-EMF for 72 h at 1 and 2 SAR, cell proliferation was consistently decreased in all the human cells. The anti-proliferative effect was higher at 2 SAR than 1 SAR and was less severe in ASCs. The exposure to RF-EMF for 72 h at 1 and 2 SAR did not induce DNA double strand breaks or apoptotic cell death, but did trigger a slight delay in the G1 to S cell cycle transition. Cell senescence was also clearly observed in ASC and Huh7 cells exposed to RF-EMF at 2 SAR for 72 h. Intracellular ROS increased in these cells and the treatment with an ROS (reactive oxygen species) scavenger recapitulated the anti-proliferative effect of RF-EMF. These observations strongly suggest that 1.7 GHz LTE RF-EMF decrease proliferation and increase senescence by increasing intracellular ROS in human cells.

Conclusion

Altogether, this study as well as other studies strongly suggest that RF-EMF exposure leads to a change in intracellular ROS levels that may result in genotoxic stress, decreased proliferation and cell senescence, or no physiological effects depending on ROS concentration and the differential sensitivity of various cells to ROS. Thus, the mechanism behind RF-EMF exposure altering intracellular ROS levels should be further studied to elucidate the biological effects of RF-EMFs.

It is not plausible to directly predict the physiological effects of 1.7 GHz LTE RF-EMF from our cell-based study. However, the anti-proliferative effect of 1.7 GHz LTE RF-EMF on various human cells in this study suggests that the exposure to 1.7 GHz LTE RF-EMF would be more harmful to children, whose adult stem cells should be very active for growth and may accelerate the aging of body cells. We also carefully suggest that the anti-proliferative effect of various cancer cells by 1.7 GHz LTE RF-EMF would be interpreted with care, considering that both positive and negative effects of RF-EMF have been reported on cancer development.


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Empirical study on specific absorption rate of head tissues due to induced heating of 4G cell phone radiation

Christopher B, Mary YS, Khandaker MU, Jojo PJ. Empirical study on specific absorption rate of head tissues due to induced heating of 4G cell phone radiation. Radiation Physics and Chemistry. Published online Apr 4, 2020. https://doi.org/10.1016/j.radphyschem.2020.108910

Highlights

• Induced heating of 4G cell phone radiation affects the functions of neural cells.
• Temperature and SAR of brain, eye and skin tissues are measured in laboratory condition.
• Rise in temperature and SAR values are found in the studied tissues for confrontation of 600 s.
• Long time and over exposure to mobile phone radiation may affect the individual health.

Abstract

Exposures to electromagnetic radiation mainly from the extended use of mobile phones may initiate biological damages in the human body at the macromolecular level. Several studies on human and animal models have shown significant changes in the functions of neural cells. Present empirical study analyses the thermal changes and the specific absorption rates (SAR) of brain, eye and skin tissues due to prolonged exposure to mobile phone radiation. A phantom, simulating human head with skin, skull and brain was used for the study. The Phantom was exposed to radiation for longer durations (600 s and more) and the temperature variations at different specific points were studied with sensitive thermocouple probes. SAR (1 g of contiguous tissue) values were determined using the variations of temperature and other parameters. The average rise in brain temperature was found to be 0.10 ± 0.05 °C at 30 mm deep in the brain and the estimated SAR was 0.66 ± 0.35 Wkg-1. The increase in temperature for the eye socket was 0.03 ± 0.02 °C with SAR 0.15 ± 0.08 Wkg-1. The average rise in temperature for skin was 0.14 ± 0.05 °C and the SAR was 0.66 ± 0.42 Wkg-1. Although the measured SAR lie within the safe limit of 2 Wkg-1 recommended by the international regulatory body, considering the tremendous growth in the number of mobile phone users and prolonged use of mobile phone in communication purposes, the cumulative effects could be a real concern for human health.


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Effects of mobile phone radiation on certain hematological parameters

Christopher B, Sheena MY, Uddin Khandaker M, Bradley DA, Chew MT, Jojo PJ.  Effects of mobile phone radiation on certain hematological parameters. Radiation Physics and Chemistry. Published online September 14, 2019. 108443. https://doi.org/10.1016/j.radphyschem.2019.108443.

Highlights

• Mobile phone radiation affects blood hemoglobin level, white blood cell and platelets count and erythrocytes sedimentation rate.
• Effects of mobile phone radiation on hematological factors studied in a controlled condition in the laboratory.
• A matched case control approach was adopted for the investigation.
• Long time and over exposure to mobile phone radiation may affect the individual health.

Abstract

Exorbitant chronic exposure to any sort of radiation is hazardous to human health. Besides ionizing radiation, exposures to electromagnetic radiation mainly from the use of mobile phones have become a matter of great health concern, especially its extortionate use even by children. At the same time there are several myths related to the ill effects including carcinogenicity of the prolonged exposure continuously. The objective of this investigation was to find the effect on certain vital hematological parameters namely hemoglobin level, white blood cell (WBC) count, platelet count and erythrocytes sedimentation rate (ESR) level due to the prolonged exposure to mobile radiations through in vitro examination of human blood samples. Matched case control methodology was adopted for the study. Blood samples were collected by clinicians from 27 voluntary subjects for investigation. From each, one sample was kept un-exposed while the other three samples were exposed to mobile microwave radiations for 60 min continuously in identical and controlled conditions. A 4G hand phone of a very popular brand having transmission frequency range from 2.3 to 2.4 GHz including uplink and downlink was used. Hematological analyses were carried out on fresh samples immediately after collection. For comparison of the levels of hematological parameters, blood exposed to 1 h of phone radiation and control were analysed. Experimental results show that there is a significant change on the hematological components. The exposed blood samples were found to have decrease in platelet count only. Hemoglobin level, ESR rate and the WBC counts were found to be increased. While these observations are performed in a controlled laboratory conditions, the tremendous growth in number of mobile phone users, the effects could be many more folds especially in work places and cities even through passive exposure.

https://www.sciencedirect.com/science/article/abs/pii/S0969806X19305481

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Early-life exposure to pulsed LTE radiofrequency fields causes persistent changes in activity and behavior in mice

Broom KA, Findlay R, Addison DS, Goiceanu C, Sienkiewicz Z. Early-life exposure to pulsed LTE radiofrequency fields causes persistent changes in activity and behavior in C57BL/6 J mice. Bioelectromagnetics. 2019 Sep 15. doi: 10.1002/bem.22217.

Abstract

Despite much research, gaps remain in knowledge about the potential health effects of exposure to radiofrequency (RF) fields. This study investigated the effects of early-life exposure to pulsed long term evolution (LTE) 1,846 MHz downlink signals on innate mouse behavior. Animals were exposed for 30 min/day, 5 days/week at a whole-body average specific energy absorption rate (SAR) of 0.5 or 1 W/kg from late pregnancy (gestation day 13.5) to weaning (postnatal day 21). A behavioral tracking system measured locomotor, drinking, and feeding behavior in the home cage from 12 to 28 weeks of age. The exposure caused significant effects on both appetitive behaviors and activity of offspring that depended on the SAR. Compared with sham-exposed controls, exposure at 0.5 W/kg significantly decreased drinking frequency (P ≤ 0.000) and significantly decreased distance moved (P ≤ 0.001). In contrast, exposure at 1 W/kg significantly increased drinking frequency (P ≤ 0.001) and significantly increased moving duration (P ≤ 0.005). In the absence of other plausible explanations, it is concluded that repeated exposure to low-level RF fields in early life may have a persistent and long-term effect on adult behavior.


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Long-term exposure to 4G smartphone radiation diminished male reproductive potential in testes of adult rats

Yu G, Tang Z, Chen H, Chen Z, Wang L, et al.  Long-term exposure to 4G smartphone radiofrequency electromagnetic radiation diminished male reproductive potential by directly disrupting Spock3-MMP2-BTB axis in the testes of adult rats. Sci Total Environ. 2019 Aug 31;698:133860. doi: 10.1016/j.scitotenv.2019.133860.

Abstract

The correlation between long-term exposure to SRF-EMR and the decline in male fertility is gradually receiving increasing attention from the medical society. While male reproductive organs are often exposed to SRF-EMR, little is currently known about the direct effects of long-term SRF-EMR exposure on the testes and its involvement in the suppression of male reproductive potential. The present study was designed to investigate this issue by using 4G SRF-EMR in rats. A unique exposure model using a 4G smartphone achieved localized exposure to the scrotum of the rats for 6 h each day (the smartphone was kept on active talk mode and received an external call for 1 min over 10 min intervals). Results showed that SRF-EMR exposure for 150 days decreased sperm quality and pup weight, accompanied by testicular injury. However, these adverse effects were not evident in rats exposed to SRF-EMR for 50 days or 100 days. Sequencing analysis and western blotting suggested Spock3 overexpression in the testes of rats exposed to SRF-EMR for 150 days. Inhibition of Spock3 overexpression improved sperm quality decline and alleviated testicular injury and BTB disorder in the exposed rats. Additionally, SRF-EMR exposure suppressed MMP2 activity, while increasing the activity of the MMP14-Spock3 complexes and decreasing MMP14-MMP2 complexes; these results were reversed by Spock3 inhibition. Thus, long-term exposure to 4G SRF-EMR diminished male fertility by directly disrupting the Spock3-MMP2-BTB axis in the testes of adult rats. To our knowledge, this is the first study to show direct toxicity of SRF-EMR on the testes emerging after long-term exposure.


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Short-term radiofrequency exposure from new generation mobile phones reduces EEG alpha power with no effects on cognitive performance.

Vecsei Z, Knakker B, Juhász P, Thuróczy G, Trunk A, Hernádi I. Short-term radiofrequency exposure from new generation mobile phones reduces EEG alpha power with no effects on cognitive performance. Sci Rep. 2018 Dec 20;8(1):18010. doi: 10.1038/s41598-018-36353-9.

Abstract

Although mobile phone (MP) use has been steadily increasing in the last decades and similar positive trends are expected for the near future, systematic investigations on neurophysiological and cognitive effects caused by recently developed technological standards for MPs are scarcely available. Here, we investigated the effects of radiofrequency (RF) fields emitted by new-generation mobile technologies, specifically, Universal Mobile Telecommunications System (UMTS) and Long-Term Evolution (LTE), on intrinsic scalp EEG activity in the alpha band (8-12 Hz) and cognitive performance in the Stroop test. The study involved 60 healthy, young-adult university students (34 for UMTS and 26 for LTE) with double-blind administration of Real and Sham exposure in separate sessions. EEG was recorded before, during and after RF exposure, and Stroop performance was assessed before and after EEG recording. Both RF exposure types caused a notable decrease in the alpha power over the whole scalp that persisted even after the cessation of the exposure, whereas no effects were found on any aspects of performance in the Stroop test. The results imply that the brain networks underlying global alpha oscillations might require minor reconfiguration to adapt to the local biophysical changes caused by focal RF exposure mimicking MP use.

Open access paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301959/

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The Effect of a Single 30-Min Long Term Evolution Mobile Phone-Like Exposure on Thermal Pain Threshold of Young Healthy Volunteers

Vecsei Z, Thuróczy G, Hernádi I. The Effect of a Single 30-Min Long Term Evolution Mobile Phone-Like Exposure on Thermal Pain Threshold of Young Healthy Volunteers. Int J Environ Res Public Health. 2018 Aug 27;15(9). pii: E1849. doi: 10.3390/ijerph15091849.

Abstract

Although the majority of mobile phone (MP) users do not attribute adverse effects on health or well-being to MP-emitted radiofrequency (RF) electromagnetic fields (EMFs), the exponential increase in the number of RF devices necessitates continuing research aimed at the objective investigation of such concerns. Here we investigated the effects of acute exposure from Long Term Evolution (LTE) MP EMFs on thermal pain threshold in healthy young adults. We use a protocol that was validated in a previous study in a capsaicin-induced hyperalgesia model and was also successfully used to show that exposure from an RF source mimicking a Universal Mobile Telecommunications System (UMTS) MP led to mildly stronger desensitization to repeated noxious thermal stimulation relative to the sham condition. Using the same experimental design, we did not find any effects of LTE exposure on thermal pain threshold. The present results, contrary to previous evidence obtained with the UMTS modulation, are likely to originate from placebo/nocebo effects and are unrelated to the brief acute LTE EMF exposure itself. The fact that this is dissimilar to our previous results on UMTS exposure implies that RF modulations might differentially affect pain perception and points to the necessity of further research on the topic.


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Modulation of brain functional connectivity by exposure to LTE (4G) cell phone radiation 

Wei Y, Yang J, Chen Z, Wu T, Lv B. Modulation of resting‐state brain functional connectivity by exposure to acute fourth‐generation long‐term evolution electromagnetic field: An fMRI study. Bioelectromagnetics. Published online 18 December 2018. 

Abstract

By now, the neurophysiological effect of electromagnetic field (EMF) exposure and its underlying regulating mechanisms are not well manifested. In this study, we aimed to investigate whether acute long‐term evolution (LTE) EMF exposure could modulate brain functional connectivity using regional homogeneity (ReHo) method and seed‐based analysis on resting‐state functional magnetic resonance imaging (fMRI). We performed the LTE‐EMF  exposure experiment and acquired the resting‐state brain activities before and after EMF exposure. Then we applied ReHo index to characterize the localized functional connectivity and seed‐based method to evaluate the inter‐regional functional connectivity. Statistical comparisons were conducted to identify the possible evidence of brain functional connectivity modulation induced by the acute LTE‐EMF exposure. We found that the acute LTE‐EMF exposure modulated localized intra‐regional connectivity (p < 0.05, AlphaSim corrected, voxel size ≥ 18) and inter‐regional connectivity in some brain regions (p < 0.05, AlphaSim corrected, voxel size ≥ 18). Our results may indicate that the approaches relying on network‐level inferences could provide deeper insight into the acute effect on human functional activity induced by LTE‐EMF exposure.

Excerpts

"Currently, multiple standards exist for wireless communication, which ranges from second‐generation (2G, GSM) to third‐generation (3G, UMTS) and fourth‐generation (4G, LTE) networks in daily life. Fifth‐generation (5G) networks will start to appear as a commercial infrastructure in the near future. Although we enjoy the convenience of mobile phones, the widespread use of them has raised attention about the possible health effects of radiofrequency (RF) electromagnetic field (EMF) exposure [ICNIRP, 1998].

With neuroimaging and neuropsychology tools, the effect of EMF on the human brain can be reflected as signals of electrical activity [Hamblin et al., 2006; Croft et al., 2010; Lustenberger et al., 2013; Roggeveen et al., 2015a, b], cortical excitability [Tombini et al., 2013], cerebral blood flow [Aalto et al., 2006], brain glucose metabolism [Volkow et al., 2011], and hemodynamic responses [Volkow et al., 2011; Curcio et al., 2012]. Previous studies reported that GSM signals modulated alpha band power in resting‐state electroencephalogram (EEG) [Croft et al., 2010] or some event‐related potential (ERP) components during cognitive tasks [Hamblin et al., 2006], whereas other studies did not detect any GSM exposure‐induced changes in brain activity [Curcio et al., 2012]. Although some studies showed no significant effects of 3G signals on any neurophysiological measurements [Zhang et al., 2017], recent EEG studies reported significant EEG alterations associated with 3G mobile phone radiation [Roggeveen et al., 2015a, b]. The inconsistency could partly be attributed to different exposure frequencies, modulation modes, and exposure durations [Zhang et al., 2017]. For 4G‐related signals, only our two previous studies have investigated the acute effect of long‐term evolution (LTE) EMF exposure on human brain function [Lv et al., 2014; Yang et al., 2016] using EEG and functional magnetic resonance imaging (fMRI). We found that 30 min of LTE‐EMF exposure modulated the alpha/beta EEG bands [Yang et al., 2016] and spontaneous low‐frequency fluctuations [Lv et al., 2014] in some brain regions. Since LTE networks have been widely deployed, we should make more effort to evaluate the possible effects of LTE‐EMF exposure from different perspectives."

"In this study, we aimed to investigate whether acute LTE‐EMF exposure could modulate brain functional connectivity using resting‐state fMRI. We performed LTE‐EMF exposure experiments lasting for 30 min under a controllable environment and recorded the resting‐state brain activities before and after EMF exposure. Then, we applied the regional homogeneity (ReHo) index [Zang et al., 2004] to characterize localized intraregional connectivity and the seed‐based functional connectivity method [Margulies et al., 2010] to evaluate interregional brain connectivity. Statistical comparisons were conducted to identify possible evidence of brain functional connectivity modulation induced by acute LTE‐EMF exposure."

“To eliminate study biases, we employed a double‐blind, crossover, randomized, and counterbalanced design. Each participant underwent two experimental sessions including real exposure and sham exposure, which were separated by 1 day….The time‐division LTE signal (2.573 GHz) was produced by a signal generator a standard formulation for LTE signals….The power delivered to the standard dipole of 2.6 GHz was 24 dBm (mean value), which was equivalent to a theoretical maximal emission by an LTE terminal. The experiments were conducted in a shielding room to avoid the influence of environmental EMF. Each exposure session lasted for 30 min.”

“Numerical simulations that yielded spatial peak SAR averaging over 10 g tissues for the subjects was 0.98 ± 0.27 W/kg, with a maximal value of 1.52 W/kg, which was below the safety limits [ICNIRP, 1998].”

“In our previous studies, we found that LTE‐EMF exposure depressed the amplitude of spontaneous low frequency fluctuations (ALFFs) in some brain regions [Lv et al., 2014], such as those surrounding the left superior temporal gyrus and middle temporal gyrus (STG_L and MTG_L), right superior temporal gyrus (STG_R), right medial frontal gyrus, and right paracentral lobule (MFG_R and PCL_R). In the present study, we found new evidence that acute LTE‐EMF exposures lasting for 30 min modulated brain functional connectivity including not only localized intraregional connectivity, but also interregional connectivity.”

"Although the SAR values by LTE‐EMF exposure indicated no obvious temperature increase during the exposure experiments and the brain was excellent in terms of thermal regulation, we could not preclude that thermal changes, even minute changes, could be responsible for the instantaneous changes in neural firing. SAR is a metric averaging over 6 min, and its applicability for neurological studies should be discussed."

Conclusion

"Our results may indicate that approaches relying on network‐level inferences can provide deeper insights into the acute effects of LTE‐EMF exposure with intensities below the current safety limits on human functional connectivity. In the future, we need to investigate the evolution of the effect over time.”


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Effect of Electromagnetic Waves from Mobile Phones on Spermatogenesis in the Era of 4G-LTE

Oh JJ, Byun SS, Lee SE, Choe G, Hong SK. Effect of Electromagnetic Waves from Mobile Phones on Spermatogenesis in the Era of 4G-LTE. Biomed Res Int. 2018 Jan 29;2018:1801798.

Abstract

Objective  To investigate the effect of long duration exposure to electromagnetic field from mobile phones on spermatogenesis in rats using 4G-LTE.

Methods  Twenty Sprague-Dawley male rats were placed into 4 groups according to the intensity and exposure duration: Group 1 (sham procedure), Group 2 (3 cm distance + 6 h exposure daily), Group 3 (10 cm distance + 18 h exposure daily), and Group 4 (3 cm distance + 18 h exposure daily). After 1 month, we compared sperm parameters and histopathological findings of the testis.

Results  The mean spermatid count (×106/ml) was 398.6 in Group 1, 365.40 in Group 2, 354.60 in Group 3, and 298.60 in Group 4 (p = 0.041). In the second review, the mean count of spermatogonia in Group 4 (43.00) was significantly lower than in Group 1 (57.00) and Group 2 (53.40) (p < 0.001 and p = 0.010, resp.). The sum of the germ cell counts was decreased in Group 4 compared to Groups 1, 2, and 3 (p = 0.032). The mean Leydig cell count was significantly decreased in Group 4 (p < 0.001).

Conclusions  The longer exposure duration of electromagnetic field decreased the spermatogenesis. Our findings warrant further investigations on the potential effects of EMF from mobile phones on male fertility.


Open access paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5896334/



May 2, 2016

By the end of 2013, 100 million cell phones in the U.S. operated on LTE. This number worldwide is expected to exceed 1 billion by the end of this year. 

Following is a summary of the second study published on the effects of 4th generation LTE cell phone radiation on the brain activity of cell phone users by the China Academy of Telecommunication Research of the Ministry of Industry and Information Technology.

The original study showed that 30 minutes of exposure to LTE phone radiation affected brain activity in the left superior temporal gyrus, left middle temporal gyrus, right superior temporal gyrus, right medial frontal gyrus and right paracentral lobule. The current study found that a 30-minute exposure to LTE radiation modulated the EEG in the alpha and beta bands at the frontal region of the near and remote sides, and at the temporal region on the near side.

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Long-Term Evolution EMF Exposure Modulates Resting State EEG on Alpha and Beta Bands

Yang L, Chen Q, Lv B, Wu T. Long-Term Evolution Electromagnetic Fields Exposure Modulates the Resting State EEG on Alpha and Beta Bands. Clin EEG Neurosci. 
2017 May;48(3):168-175. doi: 10.1177/1550059416644887.

Abstract


Long-term evolution (LTE) wireless telecommunication systems are widely used globally, which has raised a concern that exposure to electromagnetic fields (EMF) emitted from LTE devices can change human neural function. To date, few studies have been conducted on the effect of exposure to LTE EMF. Here, we evaluated the changes in electroencephalogram (EEG) due to LTE EMF exposure. An LTE EMF exposure system with a stable power emission, which was equivalent to the maximum emission from an LTE mobile phone, was used to radiate the subjects. Numerical simulations were conducted to ensure that the specific absorption rate in the subject's head was below the safety limits. Exposure to LTE EMF reduced the spectral power and the interhemispheric coherence in the alpha and beta bands of the frontal and temporal brain regions. No significant change was observed in the spectral power and the inter-hemispheric coherence in different timeslots during and after the exposure. These findings also corroborated those of our previous study using functional magnetic resonant imaging.

http://1.usa.gov/2475GM3

Excerpts

".. the results of resting state EEG experiments have been contradictory. For example, some studies have reported enhancement of the alpha (8-12 Hz) and beta (13-30 Hz) band power values after exposure to pulse-modulated 450- and 900-MHz signals, pulse-modulated magnetic fields, and active mobile phone signals. In contrast, some studies have shown decreased alpha band activity after 20 minutes of extremely low-frequency EMF exposure, or 5 minutes of magnetic field exposure, or global system for mobile communications (GSM) EMF exposure. Many studies also found no changes in the EEG after either modulated or unmodulated EMF exposure. These inconsistencies could be attributed not only to the differences in the signal type, the modulation, the exposure frequency, the exposure intensity individual anatomy, the ages of the subjects, and the exposure duration but also to the lack of rigorous experimental designs. Most of the previously published studies have focused on GSM, WiFi, and Universal Mobile Telecommunications System (UMTS), signals. An emerging technology, “long term evolution” (LTE) wireless service, has been deployed since 2009 and the number of global LTE subscribers is expected to reach 1.37 billion by the end of 2015. Other than our previous functional magnetic resonance imaging (fMRI) study, there are very few reports on the effect of exposure to LTE EMF on brain function. We previously found that 30 minutes of exposure to LTE EMF modulated the spontaneous low-frequency fluctuations. We were interested in confirming our previous results using another neurophysiological method and also sought to assess the evolution of the effect over time during such exposure. In this article, we have investigated for the first time the changes in the resting state EEG caused by exposure to LTE signals. The exposure dose was below the current safety limit. In order to assess brain activities on different levels, we evaluated spectral power and interhemispheric coherence, which allowed investigation of EEG changes in specific brain regions, as well as their correlations, at different time points. We show that exposure to LTE EMF decreased the alpha and beta band power spectrum and interhemisphere coherence."

"The age of the subjects was 30.2 ± 2.7 years."

"A plastic spacer of 1 cm was used to maintain the distance between the right ear and a standard dipole. We applied 2 power meters to ensure a constant incident power to the emission dipole. The power delivered to the dipole was 24 dBm (peak value), equivalent to a theoretical maximum emission by an LTE terminal."

"All 25 subjects participated in the double-blind and counterbalanced experiment."

"The experiment included 2 sessions, which were separated by 1 week. Each session lasted 50 minutes and comprised 5 time slots. We indicated each time slot (10 minutes) in a session as sub1 to sub5. The radiation dipole was power off for the first (preexposure, sub1) and the last 10 minutes (postexposure, sub5) timeslots. Subjects were exposed to real EMF exposure in the 3 time slots (sub2 to sub4) between the first and the last 10 minutes in only 1 of the 2 sessions. The order of the 2 sessions was randomly selected per subject. The subjects were not informed of the sequence of each session; however, they were aware of the possibility of being exposed. On the other hand, the staff who analyzed the data did not know the sources of the EEG traces."

"The simulations yielded 1.34 W/kg (pSAR10g) and 1.96 W/kg (pSAR1g), with the electrodes, and 1.27 W/kg (pSAR10g) and 1.78 W/kg (pSAR1g), without the electrodes (Figure 2) when the dipole emitted radiation. Therefore, the presence of the EEG electrodes increased pSAR10g and pSAR1g by about 5.5% and 10.1%, respectively. Accordingly, the maximum resultant temperature increase was no more than 0.1°C ...."

"Previous studies on GSM and UMTS signal exposure frequently reported changes in interhemispheric coherence and the spectral power in the alpha band in the frontal and temporal regions, which were also confirmed by our results on LTE EMF exposure. Moreover, modulation of the power spectrum in the beta band, including both an increase and a decrease, was reported. Several reasons may account for the inconsistency. First, the signal frequency and its modulation influenced the affected EEG band: for example, exposure to 2G signals affect the alpha rhythms, whilst exposure to 3G signals do not. In contrast, the modulated 450-MHz signals of various intensities can change beta activity much more markedly than alpha band power. Second, gender and the individual sensitivity 38,40 may influence the effect on different bands. Hence, we attempted to reduce the variability by enrolling the subjects with the same gender and age."

"In particular, power spectral analysis has shown significant differences in the left frontal brain regions, that is, the remote side, on exposure. This may be associated with modulation of neural activity in the remote/contralateral brain regions. The remote effects of EMF have been observed in many previous studies. Our results reconfirmed that the effects were also seen with LTE EMF exposure."

"The power spectrum and the interhemispheric coherence did not differ significantly over sub2 to sub5. Thus, the observed effect did not change with the exposure time and the effect was therefore not developing. The reduction in alpha band activity has been associated with a decrease in individual information-processing ability, alertness, and cognitive performance. The decrease in beta band activity could be interpreted as decreased alertness, arousal, and excitement or a low level of fatigue. Notably, EEG power fluctuation was not in one-one correspondence with the change in behavioral/cognitive performance which should be evaluated by specifically designed experiments as the report by Haarala et al. No conclusion could be obtained by our study that the present EMF exposure affected the subjects’ cognitive abilities."

"This work studied EEG changes caused by LTE EMF exposure. An exposure system with a fixed power incident to a radiation dipole was used; this simulation demonstrated that the SAR was within the safety limits. LTE EMF exposure modulated the EEG in the alpha and beta bands at the frontal region of the near and remote sides, and at the temporal region on the near side. No developing effect was found in the periods during and after the exposure. Our results agreed to some extent with those of our previous fMRI study on LTE exposure. Our finding indicated that the LTE EMF exposure with the intensity beneath the safety limits could modulate the brain activities."

"Future studies should focus on the correlation of EEG changes with spatial SAR distribution. By taking individual anatomical structure into consideration, a precise dose-effect relationship can be established. EEG changes with a finer temporal resolution during the exposure session should also be evaluated."


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The alteration of spontaneous low frequency oscillations caused by acute electromagnetic fields exposure

Lv B, Chen Z, Wu T, et al. The alteration of spontaneous low frequency oscillations caused by acute electromagnetic fields exposure. Clin Neurophysiol. 2014;125:277-286.

Abstract

OBJECTIVE: The motivation of this study is to evaluate the possible alteration of regional resting state brain activity induced by the acute radiofrequency electromagnetic field (RF-EMF) exposure (30 minutes) of Long Term Evolution (LTE) signal.


METHODS: We designed a controllable near-field LTE RF-EMF exposure environment. Eighteen subjects participated in a double-blind, crossover, randomized and counterbalanced experiment including two sessions (real and sham exposure). The radiation source was close to the right ear. Then the resting state fMRI signals of human brain were collected before and after the exposure in both sessions. We measured the amplitude of low frequency fluctuation (ALFF) and fractional ALFF (fALFF) to characterize the spontaneous brain activity.

RESULTS: We found the decreased ALFF value around in left superior temporal gyrus, left middle temporal gyrus, right superior temporal gyrus, right medial frontal gyrus and right paracentral lobule after the real exposure. And the decreased fALFF value was also detected in right medial frontal gyrus and right paracentral lobule.

CONCLUSIONS: The study provided the evidences that 30 minute LTE RF-EMF exposure modulated the spontaneous low frequency fluctuations in some brain regions.

SIGNIFICANCE: With resting state fMRI, we found the alteration of spontaneous low frequency fluctuations induced by the acute LTE RF-EMF exposure.

https://www.ncbi.nlm.nih.gov/pubmed/24012322

Wednesday, September 13, 2023

Trends in Brain Tumor Incidence Outside the U.S.

Because it can take a decade or more for a solid tumor to be diagnosed, it is important to model the latency when examining tumor incidence data. Nonetheless, it's tricky trying to interpret ecological studies. Moreover, trends over time in tumor incidence can be difficult to interpret due to changes in screening, diagnostic and reporting procedures.

(Many smartphones have transmission antennas in the bottom of the phones so the neck may now receive the greatest exposure during phone calls putting the thyroid gland at risk.)

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Incidence and Mortality of Malignant Brain Tumors after 20 Years of Mobile Use

Uddin M, Dhanta R, Pitti T, Barsasella D, Scholl J, Jian WS, Li YJ, Hsu MH, Syed-Abdul S. Incidence and Mortality of Malignant Brain Tumors after 20 Years of Mobile Use. Cancers (Basel). 2023 Jul 4;15(13):3492. doi: 10.3390/cancers15133492.

Simple Summary

This population-based study, spanning 20 years, revealed trends regarding the incidence and mortality due to malignant neoplasm of the brain (MNB) in association with mobile phone usage in Taiwan. The findings indicate a trend of increase in the number of mobile phone users over the study period, accompanied by a slight rise in the incidence and death rates of MNB. The compound annual growth rates further support these observations, highlighting consistent growth in mobile phone users and a corresponding increase in MNB incidences and deaths. While this study suggests a weak association between mobile phone users and MNB incidence and mortality, it is important to acknowledge that conclusive results cannot be drawn at this stage. Further investigation is required to obtain more definitive findings. Continued research in this area will contribute to better understanding of the potential risks and aid in the development of safer mobile phone usage practices in the future.

Abstract

(1) Objective: This population-based study was performed to examine the trends of incidence and deaths due to malignant neoplasm of the brain (MNB) in association with mobile phone usage for a period of 20 years (January 2000–December 2019) in Taiwan. 

(2) Methods: Pearson correlation, regression analysis, and joinpoint regression analysis were used to examine the trends of incidence of MNB and deaths due to MNB in association with mobile phone usage. 

(3) Results: The findings indicate a trend of increase in the number of mobile phone users over the study period, accompanied by a slight rise in the incidence and death rates of MNB. The compound annual growth rates further support these observations, highlighting consistent growth in mobile phone users and a corresponding increase in MNB incidences and deaths. 

(4) Conclusions: The results suggest a weaker association between the growing number of mobile phone users and the rising rates of MNB, and no significant correlation was observed between MNB incidences and deaths and mobile phone usage. Ultimately, it is important to acknowledge that conclusive results cannot be drawn at this stage and further investigation is required by considering various other confounding factors and potential risks to obtain more definitive findings and a clearer picture.

Conclusions

This population-based study, spanning 20 years, revealed trends regarding the incidence of MNB and mortality due to MNB in association with mobile phone usage in Taiwan. The findings indicate trends of increase in the number of mobile phone users over the study period, accompanied by a slight rise in the incidence and death rates of MNB. The compound annual growth rates further support these observations, highlighting the consistent growth in mobile phone users and a corresponding increase in MNB incidences and deaths. These results suggest a weaker association between the growing number of mobile phone users and the rising rates of MNB, and no significant correlation was observed between MNB incidences and deaths and mobile phone usage. In general, the literature in this context is very wide and has mixed reviews, but overall, the literature provides only a little evidence or does not show evidence of the association between mobile phone users and the development of brain tumors and death. Ultimately, it is important to acknowledge that conclusive results cannot be drawn at this stage; therefore, further investigation is required to obtain findings that are more definitive.

Considering the potential risks associated with emerging technologies such as 5G, which has higher data transmission rates and frequencies, it is crucial to examine radiation exposure levels and durations when assessing the association between mobile phone usage and cancer. Future research should explore different age groups of mobile phone users and investigate the duration of radiation exposure to gain a better understanding of their potential associations with MNB, as the latency period for brain cancer can range from 10 to 50 years. It is reassuring to know that engineers are actively working on reducing harmful radiation with the advancements of communication technologies. Continued research in this area will contribute to the better understanding of the potential risks and aids in the development of safer mobile phone usage practices in the future. Finally, further in-depth investigations for the other related confounding variables and risk factors that could be involved in the development of MNB are sine qua non for understanding the bigger picture.


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A new study in South Korea found that ten years after mobile phone subscriptions increased, the incidence of brain tumors increased in several anatomic locations (notably malignant tumors in the frontal and temporal lobes and nonmalignant tumors in the meninges) but decreased in other locations. This could be related to the adoption ten years earlier of cell phones in which transmission antennas were situated at the top of the phones. 

Jinyoung Moon, Physician's Weekly, Mar 13, 2023

The aim of this study is to investigate the relationship between the nationwide cell phone subscription rate and the nationwide incidence of brain tumors in South Korea. The nationwide cell phone subscription rate was used as a proxy for the RF-EMR [radio frequency electromagnetic radiation] exposure assessment.

The data for cell phone subscriptions per 100 persons from 1985 to 2019 were found in the Statistics, International Telecom Union (ITU). The brain tumor incidence data from 1999 to 2018 provided by the South Korea Central Cancer Registry operated by the National Cancer Center were used.

In South Korea, the subscription rate increased from 0 per 100 persons in 1991 to 57 per 100 persons in 2000. The subscription rate became 97 per 100 persons in 2009 and 135 per 100 persons in 2019. For the correlation coefficient between cell phone subscription rate before 10 years and ASIR per 100,000, a positive correlation coefficient with a statistical significance was reported in 3 benign brain tumors (International Classification of Diseases, ICD-10 code, D32, D33, and D32.0) and in 3 malignant brain tumors (ICD-10 code, C71.0, C71.1, and C71.2). Positive correlation coefficients with a statistical significance in malignant brain tumors ranged from 0.75 (95% CI 0.46-0.90) for C71.0 to 0.85 (95% CI 0.63-0.93) for C71.1.

In consideration of the fact that the main route for RF-EMR exposure has been through the frontotemporal side of the brain (the location of both ears), the positive correlation coefficient with a statistical significance in the frontal lobe (C71.1) and temporal lobe (C71.2) can be understood. Statistically insignificant results from recent cohort and large population international studies and contrasting results from many previous case-control studies could indicate a difficulty in identifying a factor as a determinant of a disease in ecological study design.

https://www.physiciansweekly.com/the-relationship-between-radiofrequency-electromagnetic-radiation-from-cell-phones-and-brain-tumor-the-brain-tumor-incidence-trends-in-south-korea/

Moon J. The relationship between radiofrequency-electromagnetic radiation from cell phones and brain tumor: The brain tumor incidence trends in South Korea. Environmental Research (2023). doi: 10.1016/j.envres.2023.115657.

Highlights

• Positive correlation for malignant neoplasm of cerebrum, except lobes and ventricles/the frontal lobe/the temporal lobe.
• Positive correlation for benign neoplasm of meninges/brain & other parts of the central nervous system/supratentorial brain.
• The highest correlation coefficient: malignant neoplasm of the frontal lobe/the temporal lobe.
• Cell phones: RF-EMR exposure through the frontotemporal side of the brain.
• Four reasons for statistically insignificant results of recent studies.

Abstract

Introduction  The aim of this study is to investigate the relationship between the nationwide cell phone subscription rate and the nationwide incidence of brain tumors in South Korea. The nationwide cell phone subscription rate was used as a proxy for the RF-EMR exposure assessment.

Methods  The data for cell phone subscriptions per 100 persons from 1985 to 2019 were found in the Statistics, International Telecom Union (ITU). The brain tumor incidence data from 1999 to 2018 provided by the South Korea Central Cancer Registry operated by the National Cancer Center were used.

Results  In South Korea, the subscription rate increased from 0 per 100 persons in 1991 to 57 per 100 persons in 2000. The subscription rate became 97 per 100 persons in 2009 and 135 per 100 persons in 2019. For the correlation coefficient between cell phone subscription rate before 10 years and ASIR per 100,000, a positive correlation coefficient with a statistical significance was reported in 3 benign brain tumors (International Classification of Diseases, ICD-10 code, D32, D33, and D32.0) and in 3 malignant brain tumors (ICD-10 code, C71.0, C71.1, and C71.2). Positive correlation coefficients with a statistical significance in malignant brain tumors ranged from 0.75 (95% CI 0.46–0.90) for C71.0 to 0.85 (95% CI 0.63–0.93) for C71.1.

Discussion  In consideration of the fact that the main route for RF-EMR exposure has been through the frontotemporal side of the brain (the location of both ears), the positive correlation coefficient with a statistical significance in the frontal lobe (C71.1) and temporal lobe (C71.2) can be understood. Statistically insignificant results from recent cohort and large population international studies and contrasting results from many previous case-control studies could indicate a difficulty in identifying a factor as a determinant of a disease in ecological study design.

Excerpts

Numerous systematic reviews and meta-analyses on the association between Radiofrequency-Electromagnetic Radiation (RF-EMR) exposure from cell phones and the incidence of brain tumors have been published until the present time (Belpomme et al., 2018; Elwood, 2003; Morgan et al., 2015; Myung et al., 2009; Wang et al., 2018). The conclusion of each study varied depending on the magnitude of exposure, the location of brain tumors, the histologic type of brain tumors, and a number of confounding factors such as research team and funding source (Belpomme et al., 2018; Hardell et al., 2008a; Morgan et al., 2015; Wang et al., 2018)....

... in consideration of limited data for accurate RF-EMR exposure assessment, the best strategy to approach this topic is the triangulation of the pieces of information from the different types of epidemiologic studies (de Vocht and Röösli, 2021). As one piece of information from this perspective, we looked over the incidence trend of brain tumors classified by the histological types and the location of brain tumors in South Korea....

C70 Malignant neoplasm of meninges
C71 Malignant neoplasm of brain
C72 Malignant neoplasm of the spinal cord, cranial nerves, and other parts of the central nervous system
C70.0 Malignant neoplasm of cerebral meninges
C70.9 Malignant neoplasm of meninges, unspecified
C71.0 Malignant neoplasm of cerebrum, except lobes and ventricles
C71.1 Malignant neoplasm of the frontal lobe
C71.2 Malignant neoplasm of the temporal lobe
C71.9 Malignant neoplasm of brain, unspecified
C72.0 Malignant neoplasm of spinal cord
D32 Benign neoplasm of meninges
D33 Benign neoplasm of brain and other parts of the central nervous system
D32.0 Benign neoplasm of brain

The AAPC [average annual percent change] for C72, C71.0, C71.1, C71.2, C72.0, D32, D33, and D32.0 was positive with statistical significance.... The AAPC for C70, C70.0, and C71.9 was negative with statistical significance.

For the correlation coefficient between cell phone subscription rate before 10 years and ASIR per 100,000, a positive correlation coefficient with a statistical significance was reported in 3 benign brain tumors (D32, D33, and D32.0) and in 3 malignant brain tumors (C71.0, C71.1 and C71.2). A negative correlation coefficient with statistical significance was reported in 3 malignant brain tumors: C70, C70.0, and C71.9 [i.e., malignant meninges, cerebral meninges, and brain, unspecified].

Conclusion

In South Korea, for the correlation coefficient between cell phone subscription rate before 10 years and ASIR per 100,000, a positive correlation coefficient with a statistical significance was reported in 3 malignant brain tumors (C71.0, C71.1, and C71.2) [i.e., cerebrum except lobes and ventricles, frontal lobe and temporal lobe] and 3 benign brain tumors (D32, D33, and D32.0) [i.e. nonmalignant meninges, brain and other CNS, and brain, supratentorial]. Among these results, that for malignant brain tumors in the frontal lobe (C71.1) and in the temporal lobe (C71.2) is suspicious of the association with RF-EMR emitted from cellular phones. The other 4 possible hypotheses do not fit well with the observed phenomena.

Statistically insignificant results from recent cohort or large population international studies and contrasting results from many previous case-control studies might come from several issues. A statistically significant increased risk can be found if (ⅰ) a more accurate exposure assessment such as site-specific, time-integral of SAR for each individual is applied or (ⅱ) massive populations over 100,000 are studied.

https://www.sciencedirect.com/science/article/pii/S0013935123004498  

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Use of mobile phones and progression of glioma incidence in four Nordic countries since 1979

My notes: 

Although the title of the following report from the WHO International Agency for Research on Cancer is in German, the report is available in English. 

The report's summary, "no indications of a detectable effect of mobile phones have been found," seems misleading because it is inconsistent with the report's final conclusion, namely, "An increased risk in the 10% heaviest mobile phone users was an exception to this general situation, as it remained plausible."

[The 10% "heaviest mobile users" in the Interphone study had 1,640 or more hours of lifetime call time. That would amount to approximately 30 minutes per day over a 10-year period.]

The report's bottom line: 

"This ecological data is not sufficient to dismiss every potential mobile phone related risk scenario, but suggests that the risk – if it exists - would be very small, only occur after very long latency periods of several decades, or only affect small subgroups within glioma patients." 

If only a portion of the population has a genetic susceptibility to brain cancer in the presence of microwave radiation as appears to be the case with thyroid cancer (Luo et al., 2020), that could explain why the odds ratios obtained for brain cancer risk from case-control studies of heavy, long-term mobile phone users over-predict glioma incidence in the overall population based upon tumor registry data.
* Luo J, Li H, Deziel NC, Huang H, Zhao N, Ma S, Nie X, Udelsman R, Zhang Y. Genetic susceptibility may modify the association between cell phone use and thyroid cancer: A population-based case-control study in Connecticut. Environmental Research. 2020 Mar;182:109013. doi: 10.1016/j.envres.2019.109013. (see also Thyroid Cancer and Mobile Phone Use)

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Deltour I, Schuz J. Nutzung von Mobiltelefonen und Verlauf der Gliom-Inzidenz seit 1979: Vorhaben 3618S00000 (FM 8867). International Agency for Research on Cancer. Jun 2022. Open access report: https://doris.bfs.de/jspui/bitstream/urn:nbn:de:0221-2022063033222/4/BfS_2022_3618S00000.pdf

Summary

1.1 Introduction

In the Nordic countries, the sharp increase in the use of mobile phone occurred in the mid-1990s among adults; thus, time trends in glioma incidence rates (IR) may provide information about possible risks associated with mobile phone use. We investigated time trends in IR of glioma, and compared IR and observed number of cases to those that would be expected under a range of hypothetical mobile phone risk scenarios, encompassing risk levels reported in published case-control studies.

1.2 Methods

We analyzed age standardised IR of glioma in Denmark, Finland, Norway, and Sweden among adults 20-84 years old, using data from national cancer registries and population data covering the period 1979-2016, using a log linear joinpoint analysis. Exposure distribution of use and of high level of use were obtained from self-reported information in the Nordic Interphone, the Cosmos-Denmark and the Cosmos-France datasets. Based on analytical epidemiological studies, we considered various scenarios according to which mobile phone use would hypothetically increase the glioma risk. We quantified compatibility, or absence of compatibility between the observed data and the risk scenarios by projecting incidence rates of glioma of men aged 40-69 years old under these scenarios and comparing them with the observed incidence rates in the Nordic countries.

1.3 Results

Glioma IR increased regularly with annual percent change (APC) of 0.6 (95% confidence interval (CI) 0.4-0.7) in men and 0.3 (95%CI 0.2-0.5) in women in the period 1979-2016. There were hardly any changes in IR among men and women below age 59. In men and women in their sixties, IR increased by 0.6 (95%CI 0.4-0.9) in men and 0.4 (95%CI 0.2-0.7) in women, regularly for the whole period of observation, while IR among 70-84 years old increased very markedly, with APC of 3.1 (95%CI 2.6-3.5) among men and 2.8 (95%CI 2.3-3.3) among women over at least the last 2 decades of observation. Very few risk scenarios appeared compatible with the observed data using standardised incidence ratios analyses. The risk scenarios that appeared compatible involved either long latencies (20 years), or very low risks (RR = 1.08); in these projections, risks that would be limited to mobile phone heavy users were not compatible with the observed number of cases.

1.4 Discussion

IR time trends did not demonstrate breakpoints in their secular evolution in the last 20 years. Virtually all the reported results from the case-control studies with a positive association between mobile phone use and glioma risk were shown to be implausible in our simulations comparing them with the observed incidence rates, implying that biases and errors have likely distorted their findings; very low risks at the population level, and risks after very long latencies remained plausible. Simulations were based on high quality case registration, which is a strength, while the uncertainties in the exposure information and the limited information about some of the model’s assumptions were limitations. Altogether, this study confirms and reinforces conclusions made previously, that no indications of a detectable effect of mobile phones have been found.

Excerpts

... We analyzed the time trends in the incidence rates of glioma among adults aged 20 to 84 years of the Nordic countries from 1979 to 2016 (step 1 of the work description). Then, we addressed the question whether the observed time trends and observed number of cases were statistically different from the one we would observe if we assumed that the use of mobile phones caused glioma, so if we assumed that there was a true causal association (step 2 and step 3 of the work description). Within this, we delineated the levels of risks and the duration of induction periods that would not be compatible with the observed time trends and numbers of cases in this population (step 3 of the work description). We also discussed these findings in light of some of the elevated OR found in the literature. The study tested the consistency between risks that have been reported and the effect they would have had at the level of the population, had they been true. Noteworthy, the study was not meant to dismiss every single hypothetical association, as it would most likely always be possible to devise a pattern of risk that would fit the data....

This study was based on 28,015 male and 20,630 female glioma cases diagnosed from 1979 to 2016 in Denmark, Finland, Norway and Sweden (called “the Nordic countries” in the following). In 2016, the number of glioma cases was 1,724 in a population of 19.7 million adults aged 20–84 years. Over the last 10 years of data, Sweden accounted for 38% of the population and of the cases; of the remainder, Denmark, Finland, and Norway had populations of similar size. The age-standardized incidence rates were higher in men (9.1 per 100000 person years) than in women (6.1 per 100 000 person years), and higher with increasing age. All countries had comparable rates; Norway had slightly higher rates, while Finland had slightly lower rates in both sexes (Table 2 and Table 3).

Joinpoint analyses described in paragraph 6.1 showed that overall, the trends were smooth: glioma rates increased by 0.6% (95% CI 0.4%-0.7%) per year in men and 0.3% (95% CI 0.2%-0.5%) per year in women over the period 1979-2016 in the Nordic countries combined (Table 4 and Table 5), and in each country separately except for a marked increase in 1979-1984 in Swedish men (APC about 6%). For the younger age groups (20-39 and 40-59 years old), the time trends were smooth and did not demonstrate strong increases at any point in time during the period 1979 to 2016 in any country among men (Table 6), and women (Table 7). Below the age of 60, incidence rates were generally stable over the whole period (Figure 1, Table 6 and Table 7). Among people aged 60-69 years old, incidence rates increased gradually by 0.6% in men and 0.4% in women per year, and these regular increases with no joinpoint were observed in every country and at a very similar rate in both sexes, except among Swedish women, whose rates showed a slight decrease. Irregular patterns were observed among the persons aged 70-84 years old at the beginning of the observation period, while for at least the last 12 years of observation, all countries showed highly increasing rates. Exceptions to this general pattern were noted among the Finnish males and the Norwegian females, in which an increase was seen at the beginning of the observation period that lasted at least 21 years.

The analysis by subgroups of tumour types could be performed only for the period 1990-2016 for reasons of data availability: in Sweden, a separate code for glioblastoma did not exist prior to 1993, and very few of the tumours which had been diagnosed during the period 1990-1992 were retrospectively coded into this code. Indeed, cancer registries are continuously updated when additional information becomes available on an earlier diagnosis, for example.

Among men and women, the rates of glioblastomas increased in the last years of observations, while the rate of other high-grade gliomas decreased (Table 8 and Table 9). Rates of low grade gliomas were relatively stable in all countries since the mid 1990’s except in Denmark, where substantial increases were noted towards the end of the period of observation, albeit non-significant....

When examining the trends by subtypes, glioblastoma generally increased while other high grade gliomas decreased, and low grade glioma were stable in the most recent period, except in Denmark where low grade glioma rates increased among men and women in the last 3 years of observation. In Sweden, the rates of glioblastoma underwent most changes, namely the increase in glioblastoma rates in Sweden in the years after the introduction of that code by the cancer registry, since a new code is not mandatorily fully used immediately after it is introduced....

To sum up, our simplified and more sophisticated analyses appeared to indicate that the small increase in IR of men age 40-59 and the marked increase in RR of men aged 60-69 were generally not compatible with the same mobile phone related risks increases. When models in which the totality of the IR increases were assumed to be associated with mobile phone effects, a RR of 1.31 that would start 20 years after first using a mobile phone was borderline compatible between these 2 age groups, while all other induction periods (0, 5, 10, 15 years) or heavy users risk scenarios produced RR estimates and CI which did not overlap between the 2 age groups when the same exposure distribution was considered. When half of the IR increases were attributed to other factors, none of the mobile phone related risks scenarios were compatible with the data, in the SIR analyses (assuming the same risk in both age groups). When most (75%) of the IR increases were attributed to other factors, then small excess risks (RR= 1.08 applying to all users after 10 years) or risks after long latencies (RR = 1.3 applying to all users after 20 years) were compatible with the observed incidence rates and exposure distributions that we assumed. Further work on these scenarios could shed more light on the remaining uncertainties. Of note, scenarios of risks limited to heavy users groups did not appear compatible with the observed number of cases in these analyses....

Our simulation study is not free of assumptions. The induction period relating mobile phone use and glioma risk, if such an association exists, is unknown, so is the magnitude of the risk, and the real patterns may be more complex than the scenarios that we simulated. In addition, there are several factors that we did not account for. The coverage of the Nordic cancer registries was not complete, but some 1.5% to 10% of the malignant tumours were missed in this age group. In Sweden, it has been estimated that completeness would not have changed over the period 1998-2014, while completeness might have improved in other countries. We modelled that other, yet to be discovered, risk factors of the disease as well as improvement in its detection and reporting had a smooth, gradual impact, over the period 1979-2016, which is consistent with the gradually increasing IR. We used 3 sources of information on the use of mobile phones, all self-reported, to evaluate the prevalence of use and heavy use up to 2002, 2008 or 2016 and extrapolated the prevalences for the periods and age groups for which no data was available, based on the trends observed in the other age groups. The use of hands-free devices was not accounted for, although this was not frequent in these populations (data not shown).

In conclusion, it is difficult to demonstrate the absence of risk, in real life condition, and assumptions about the impact of the improvement of diagnosis tools, treatment and registration changes over time were used in our simulations. However, based both on the observed IR and the simulations, we reiterate and strengthen our previous conclusion that, the risk, should one exist, ought to be lower or occur after a longer induction period or act on a smaller population, or a combination of these, than most of the level of risk that have been reported in previously published case-control studies.

Conclusions

In this project we projected incidence rates of glioma under various scenarios of mobile phone-associated increased glioma risks, and compared them with the observed incidence rates in the Nordic countries. The comparison was carried out on the data of men aged 40 to 69 years. The modelled scenarios included risk increases reported from analytical epidemiological studies, which were all of case-control design. Most of those results were shown to be implausible in our simulations, implying that biases and errors in the self-reported use of mobile phones have likely distorted their findings. An increased risk in the 10% heaviest mobile phone users was an exception to this general situation, as it remained plausible. Results of cohort studies showing no association were compatible with observed incidence rates. We also studied what hypothetical mobile phone-related risks were conceivable if the changes in incidence rates in 40-59 year old and 60-69 year old men were fully attributable to mobile phone use. The fact that we observed different hypothetical risks in these two age groups while research at present has not suggested that older men should have higher risk related to mobile phone use than younger men, does not align with the assumption that mobile phone exposures caused the incidence rate trends. This ecological data is not sufficient to dismiss every potential mobile phone related risk scenario, but suggests that the risk – if it exists - would be very small, only occur after very long latency periods of several decades, or only affect small subgroups within glioma patients.

Open access report: https://doris.bfs.de/jspui/bitstream/urn:nbn:de:0221-2022063033222/4/BfS_2022_3618S00000.pdf

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Incidence trends of adult malignant brain tumors in Finland, 1990-2016

Natukka T, Raitanen J, Haapasalo H, Auvinen A. Incidence trends of adult malignant brain tumors in Finland, 1990-2016. Acta Oncol. 2019 Apr 15:1-7. doi: 10.1080/0284186X.2019.1603396.

Abstract

BACKGROUND: Several studies have reported increased incidence trends of malignant gliomas in the late 1900s with a plateau in the 2000s, but also some  recent increases have been reported. The purpose of our study was to analyze incidence trends of malignant gliomas in Finland by morphology and tumor location.

MATERIAL AND METHODS: Data on 4730 malignant glioma patients were obtained from case notifications to the nationwide, population-based Finnish Cancer Registry (FCR), and less detailed data on 3590 patients up to 2016. Age-standardized incidence rates (ASR) and average annual percent changes (APCs) in the incidence rates were calculated by histological subtype and tumor location.

RESULTS: The incidence rate of gliomas was 7.7/100,000 in 1990-2006 and 7.3 in 2007-2016. The incidence of all gliomas combined was stable during both study periods, with no departure from linearity. In an analysis by age group, increasing incidence was found only for ages 80 years and older (1990-2006). During both study periods, incidence rates were increasing in glioblastoma and decreasing in unspecified brain tumors. In 1990-2006, rates were also increasing for anaplastic oligodendroglioma, oligoastrocytoma and unspecified malignant glioma, while decreasing for astrocytoma. As for tumor location, incidence in 1990-2006 was increasing for frontal lobe and brainstem tumors, as well as those with an unspecified location, but decreasing for the parietal lobes, cerebrum and ventricles.

CONCLUSIONS: No increasing incidence trend was observed for malignant gliomas overall. An increasing incidence trend of malignant gliomas was found in the oldest age group during 1990-2006.



Excerpts

The incidence trend of glioblastoma was slightly increasing (APC: +0.8%; 95% CI: 0.0, +1.7 for 1990–2006 and +1.9%; 95% CI: +0.2, +3.5 for 2007–2016; Tables 2 and 3).

Incidence of glioblastoma increased slightly throughout the study period, while unspecified tumors of the brain showed a decreasing incidence trend.

We also found a slightly increasing incidence trend for the most common histological subtype, glioblastoma, which is consistent with several other studies [1,5,7–9,11,17,18]. A study from United States showed an increasing incidence trend for gliomas in the frontal lobe and decreasing trends for the cerebrum, ventricles and overlapping subtypes [17].

References

[1] Ostrom QT, Gittleman H, Liao P, et al. CBTRUS statistical report: primary brain and other central nervous system tumors diagnosed in the United States in 2010–2014. Neuro Oncol. 2017;19: v1–v88.
[5] Ho VKY, Reijneveld JC, Enting RH, et al. Changing incidence and improved survival of gliomas. Eur J Cancer. 2014;50:2309–2318.
[7] Arora RS, Alston RD, Eden TOB, et al. Are reported increases in incidence of primary CNS tumours real? An analysis of longitudinal trends in England, 1979–2003. Eur J Cancer. 2010;46: 1607–1616.
[8] Deorah S, Lynch CF, Sibenaller ZA, et al. Trends in brain cancer incidence and survival in the United States: surveillance, epidemiology, and end results program, 1973 to 2001. Neurosurg Focus. 2006;20:E1.
[9] Hess KR, Broglio KR, Bondy ML. Adult glioma incidence trends in the United States, 1977–2000. Cancer. 2004;101:2293–2299.
[11] Lonn S, Klaeboe L, Hall P, et al. Incidence trends of adult primary intracerebral tumors in four Nordic countries. Int J Cancer. 2004; 108:450–455.
[17] Zada G, Bond AE, Wang YP, et al. Incidence trends in the anatomic location of primary malignant brain tumors in the United States: 1992–2006. World Neurosurg. 2012;77:518–524.
[18] Dubrow R, Darefsky AS. Demographic variation in incidence of adult glioma by subtype, United States, 1992–2007. BMC Cancer. 2011;11:325.

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Trends in the incidence of primary brain, central nervous system and intracranial tumors in Israel, 1990-2015

Keinan-Boker L, Friedman E, Silverman BG. Trends in the incidence of primary brain, central nervous system and intracranial tumors in Israel, 1990-2015. Cancer Epidemiol. 2018 Oct;56:6-13. doi: 10.1016/j.canep.2018.07.003.

Highlights

• Exponential growth in cellphone use fueled concerns regarding brain and CNS tumors.
• Results so far are inconsistent. Studying cancer incidence trends may thus be informative.
• We studied brain tumor trends from 1990 to 2015 in Israel, when cellphone use dramatically increased.
• Results do not support a substantial role for cellphone use; smaller risks in special subgroups may exist.
• Future research is needed; implementation of the precautionary principle is prudent.

Abstract

BACKGROUND: The association between cellphone technology and brain, central nervous system (CNS) and intracranial tumors is unclear. Analysis of trends in incidence of such tumors for periods during which cellphone use increased dramatically may add relevant information. Herein we describe secular trends in the incidence of primary tumors of the brain and CNS from 1990 to 2015 in Israel, a period during which cellphone technology became extremely prevalent in Israel.

METHODS: All cases of primary brain, CNS and intracranial tumors (excluding lymphomas) diagnosed in Israel from 1990 to 2015 were identified in the Israel National Cancer Registry database and categorized by behavior (malignant; benign/uncertain behavior) and histologic type. Annual age-standardized incidence rates by sex and population group (Jews; Arabs) were computed, and the annual percent changes and 95% confidence intervals per category were calculated using Joinpoint software.

RESULTS: Over 26 years (1990-2015) no significant changes in the incidence of malignant brain, CNS and intracranial tumors were observed, except for an increase in malignant glioma incidence in Jewish women up to 2008 and Arab men up to 2001, which levelled off in both subgroups thereafter. The incidence of benign/uncertain behavior brain, CNS and intracranial tumors increased in most population groups up to the mid-2000s, a trend mostly driven by changes in the incidence of meningioma, but either significantly decreased (Jews) or stabilized (Arabs) thereafter.

CONCLUSIONS: Our findings are not consistent with a discernable effect of cellphone use patterns in Israel on incidence trends of brain, CNS and intracranial tumors.


Excerpts

"When cancer occurrence rates referred to glioblastomas only, Joinpoint analysis of incidence trends was restricted to the period from 1995 to 2015 due to small numbers of cases in the Arab population prior to 1995. Stable incidence trends were noted, with non-significant APCs, in all population subgroups: APC1995–2015 for Jewish men was +0.6% (95%CI -0.4%,+1.6%); APC1995–2015 for Jewish women was +0.6% (95%CI -0.1%,+1.6%); APC1995–2015 for Arab men was -1.6% (95%CI -3.9%,+0.8%); APC1995–2015 for Arab women was +0.4% (95%CI -2.9%,+3.8%).

Analysis of time trends by age groups disclosed stable trends in most population- age- and sex groups, except for a mild increase in Jewish males aged 65 and over (APC1990–2015 +1.2%, p < 0.05) and in Arab males aged 20–64 (APC1990–2015 +1.5%, p < 0.05). In the population of Arab females, lack of cases in the age groups of 20–64 and 65+ in certain years prevented an analysis of trends."

"However, ecologic studies, of which ours is an example, may be insensitive to excess in risk which is restricted to certain groups (for example, heavy users or subjects exposed from very young ages) or to certain tumor types (e.g., tumors that are very rare, that involve specific anatomical sites, or that have unusually long latency periods) [34]. Little et al. [35] also commented that the predicted rates of glioma based on data derived from the small proportion of highly exposed people in the Interphone study, could be consistent with the observed rates in their study [35]. Therefore, although a substantial risk is not very plausible, smaller risks cannot be ruled out and future research should address specific exposure groups, and tumor types and sites, and should allow for longer follow up periods."

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England: Brain Cancer Incidence Increased in Temporal and Frontal Lobes of Brain since 1995

A new study of cancer data in England essentially replicated the results of the Philips et al study (see below). The study found that the two age groups most vulnerable to carcinogenic effects from cell phone use -- young and elderly adults -- showed increased incidence over time in brain cancer in the frontal and temporal lobes of the brain -- the two lobes that receive the greatest dose of microwave radiation when cell phones are used near the head during phone calls.

However, Frank de Vocht, the author of this paper, rejected the explanation that cell phone use caused the increased cancer risk. He attributed the increased incidence to better diagnosis of brain tumors, especially in the elderly. Of course, this does not explain why the increase was only observed in the frontal and temporal lobes. He did not rule out the possibility that cell phone radiation may be a contributing factor to the observed increase.

Microwave News reported on this study and published the following graph obtained from Alasdair Philips (Microwave News, "Location, Location, Location: Aggressive Brain Tumors Tell a Story; GBM Rise Only in Frontal and Temporal Lobes, Oct 26, 2018.)




de Vocht F. Analyses of temporal and spatial patterns of Glioblastoma Multiforme and other brain cancers subtypes in relation to mobile phones using synthetic counterfactuals. Environmental Research. Available online 17 October 2018. https://doi.org/10.1016/j.envres.2018.10.011.

Highlights

• English 1985–2005 brain cancer subtype rates were compared to counterfactual trends
• Excess GBM increases were found in the frontal and temporal lobes, and cerebellum
• Mobile phone use was unlikely to have been an important putative factor
• No evidence of an effect of mobile phone use on acoustic neuroma and meningioma

Abstract

This study assesses whether temporal trends in glioblastoma multiforme (GBM) in different brain regions, and of different malignant and benign (including acoustic neuroma and meningioma) subtypes in the temporal lobe, could be associated with mobile phone use.

Annual 1985–2005 incidence of brain cancer subtypes for England were linked to population-level covariates. Bayesian structural timeseries were used to create 2006–2014 counterfactual trends, and differences with measured newly diagnosed cases were interpreted as causal effects.

Increases in excess of the counterfactuals for GBM were found in the temporal (+38% [95% Credible Interval -7%,78%]) and frontal (+36% [-8%,77%]) lobes, which were in agreement with hypothesised temporal and spatial mechanisms of mobile phone usage, and cerebellum (+59% [-0%,120%]). However, effects were primarily present in older age groups, with largest effects in 75+ and 85+ groups, indicating mobile phone use is unlikely to have been an important putative factor. There was no evidence of an effect of mobile phone use on incidence of acoustic neuroma and meningioma.

Although 1985–2014 trends in GBM in the temporal and frontal lobes, and probably cerebellum, seem consistent with mobile phone use as an important putative factor, age-group specific analyses indicate that it is unlikely that this correlation is causal.

Excerpts

Assessment of specific cancer subtypes in the temporal lobe indicated that the excess incidence was mainly found for GBM, with similar trends observed in the frontal lobe and cerebellum....  The increased rates of specific brain cancer subtypes in excess of the counterfactuals correspond to the spatial and temporal patterns that would be expected if exposure to RF from mobile phones were an important putative factor (Cardis et al., 2008, Morgan et al., 2016) ... However, age group-specific analyses indicate that the excess relative impacts increased with age over 65 years and were primarily found in the very old (75/85+ years of age) for whom it is unlikely that mobile phone use had been an important causal factor. In addition, excess numbers of newly diagnosed cases were also observed in the young (<24 years of age) for whom mobile phone use is also an unlikely causal factor....

The assumption that a 10-year lag was the most plausible period between first exposure and when increased risk could be observed in registry data was based on the previous analyses (De Vocht (2016)). Although sensitivity analysis using a 15-year lag showed no evidence of excesses relative to counterfactuals, this may still have been too short....
This study, in agreement with other data from the UK and elsewhere, shows that the incidence of glioblastoma multiforme (astrocytoma grade IV) has increased significantly since the 1980s, especially in the frontal and temporal lobes and cerebellum. However, it further provides evidence that the trend of increasing numbers of newly diagnosed cases of glioblastoma multiforme in the temporal lobe (but likely in the frontal lobe and cerebellum as well) since the mid-1980s, although seemingly consistent with the hypothesis of exposure to radiofrequency radiation from mobile phones being an important putative factor, should to a large extent (if not exclusively) be attributed to another factor or factors; of which improvements in diagnostic techniques, especially in the elderly, seems the most plausible. Although these analyses indicate that it is unlikely that exposure to RF from mobile phones is an important putative factor, they also cannot exclude it as a contributing factor completely. It is therefore important to keep monitoring incidence trend data.

Competing financial interests declaration: The author has previously done consulting for EPRI [Electric Power Research Institute], not related to this work. 

Financial support: No external funding was obtained for this study.



Mar 25, 2018

England: Rates of Aggressive Brain Cancer Increased from 1995 to 2014

A newly-published study of brain tumor incidence trends in England from 1995 to 2014 found that the trends over time varied by type of cancer, especially in the frontal and temporal lobes.

The study found “a sustained and highly statistically significant” increase in glioblastoma multiforme (GBM), the most common brain cancer, across all ages. The rate of GBM more than doubled from 2.4 to 5.0 per 100,000 people. However, this increase was mostly hidden because the overall malignant brain tumor trend was relatively flat due to a reduced incidence of lower grade brain tumors.

In England in 1995, when the tumor site was specified at the time of diagnosis, the frontal or temporal lobes of the brain accounted for 41% of malignant brain tumors. By 2015, these two sites accounted for 60% of the tumors.

One cannot know from tumor registry data alone what caused these differential trends in brain cancer. Based upon epidemiologic research, the most compelling explanation for the increased incidence in these deadly brain tumors, especially in the frontal and temporal lobes, may be exposure to microwave radiation due to widespread adoption of cell phones. However, the increased use of CT imaging scans is an alternative, but less compelling, explanation because far fewer people would have been exposed to this form of ionizing radiation.

In the U.S., Zada and his colleagues (2012) obtained similar results in an analysis of national tumor registry data from 1992 to 2006.

Those who cite statistics which appear to show a flat-line trend in overall brain tumor incidence and argue that cell phone use doesn’t cause brain cancer need to examine data on the location and type of brain tumors over time.

Also see:


Microwave News. “Aggressive Brain Tumors on the Rise in England.” March 25, 2018. http://microwavenews.com/news-center/gbms-rising-uk


Source: Alasdair Philips via Microwave News.

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Brain tumours: rise in Glioblastoma Multiforme incidence in England 1995–2015 suggests an adverse environmental or lifestyle factor

Alasdair Philips, Denis L. Henshaw, Graham Lamburn, and Michael O'Carroll. Brain tumours: rise in Glioblastoma Multiforme incidence in England 1995–2015 suggests an adverse environmental or lifestyle factor. Journal of Environmental and Public HealthArticle ID 7910754, https://doi.org/10.1155/2018/7910754. 2018.

Highlights

• A clear description of the changing pattern in incidence of brain tumour types
• The study used extensive data from an official and recognised quality source
• The study included histological and morphological information
• The study identified a significant and concerning incidence time trend
• Some evidence is provided to help guide future research into causal mechanisms

Abstract

Objective To investigate detailed trends in malignant brain tumour incidence over a recent time period.

Methods UK Office of National Statistics (ONS) data covering 81,135 ICD10 C71 brain tumours diagnosed in England (1995–2015) were used to calculate incidence rates (ASR) per 100k person–years, age–standardised to the European Standard Population (ESP–2013).

Results We report a sustained and highly statistically significant ASR rise in glioblastoma multiforme (GBM) across all ages. The ASR for GBM more than doubled from 2.4 to 5.0, with annual case numbers rising from 983 to 2531. Overall, this rise is mostly hidden in the overall data by a reduced incidence of lower grade tumours.

Conclusions The rise is of importance for clinical resources and brain tumour aetiology. The rise cannot be fully accounted for by promotion of lower–grade tumours, random chance or improvement in diagnostic techniques as it affects specific areas of the brain and only one type of brain tumour. Despite the large variation in case numbers by age, the percentage rise is similar across the age groups which suggests widespread environmental or lifestyle factors may be responsible.


 Conclusions

1/. We show a linear, large and highly statistically significant increase in primary GBM tumours over 21 years from 1995–2015, especially in frontal and temporal lobes of the brain. This has aetiological and resource implications.
2/. Although most of the cases are in the group over 54 years of age, the age–standardised AAPC rise is strongly statistically significant in all our three main analysis age groups.

3/. The rise in age–standardised incidence cannot be fully accounted for by improved diagnosis as it affects specific areas of the brain and just one type of brain tumour which is generally fatal. We suggest that widespread environmental or lifestyle factors may be responsible.

4/. Our results highlight an urgent need for funding more research into the initiation and promotion of GBM tumours. This should include the use of CT imaging for diagnosis and also modern lifestyle factors that may affect tumour metabolism.