UK: 20 recente studies verzameld door Powerwatch.
maandag, 30 juli 2012 - Categorie: Onderzoeken
Bron: Powerwatch 29 juli 2012
Onderstaande verzameling van 20 recent gepubliceerde relevante studies, sommige reeds door Stopumts gepubliceerd:
1. - Repacholi M et al, (July 2012) Scientific basis for the Soviet and Russian radiofrequency standards for the general public, Bioelectromagnetics. 2012 Jul 2. doi: 10.1002/bem.21742. Epub ahead of print View Author's abstract conclusions View on Pubmed
The former Soviet Union (USSR) and the USA were the first countries to introduce standards limiting exposure to radiofrequency (RF) fields. However, the exposure limits in the USSR standards were always much lower than those in the USA and other countries. The objective of this article is to provide a history of the development of the Soviet and Russian RF standards. In addition, we summarize the scientific evidence used to develop the original USSR RF and subsequent Russian public health standards, as well as the mobile telecommunications standard published in 2003, but we do not critique them. We also describe the protective approaches used by the Soviet and Russian scientists for setting their limits. A translation of the papers of the key studies used to develop their standards is available in the online version of this publication. It may appear strange for those familiar with the EMF world to see Mike Repacholi and Yuri Grigoriev as the two lead authors on a shared piece of work, but as the dichotomy between common Western RF exposure limits and Russian RF exposure limits has been a source of debate for some time, we feel collaboration is a potentially very positive step. The basic summary of this paper appears to be that the Russians have a fundamentally different and more cautious approach based on the principle of protecting the public against possible effect, whereas the Western standards setting bodies typically require a strong and compelling evidence base before any standards can be set. It is good to see that neither approach was critical of the other in this paper, and whilst the paper recognised the limitations of the methodology in some of the earlier Russian experiments (simply because of the equipment and knowledge at the time limiting study quality), there were no statements that Russian guidance levels were inappropriate or unwarranted.
2. - Zada G et al, (March 2012) Incidence trends in the anatomic location of primary malignant brain tumors in the United States: 1992-2006, World Neurosurg. 2012 Mar;77(3-4):518-24. Epub 2011 Nov 7 View Author's abstract conclusions View on Pubmed
This study sought to determine incidence trends of the anatomical origin of primary malignant brain tumors. Incidence data for histologically confirmed brain tumors were obtained from the Los Angeles County Cancer Surveillance Program (LAC), the California Cancer Registry (CCR), and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program for 1992 to 2006. Age-adjusted incidence rates (AAIR) and annual percent changes (APC) were calculated by histologic subtypes and anatomic subsites. Statistical analyses were performed using the SEER*Stat analytic software and SAS statistical software. Increased AAIRs of frontal (APC +2.4% to +3.0%, P = 0.001) and temporal (APC +1.3% to +2.3%, P = 0.027) lobe glioblastoma multiforme (GBM) tumors were observed across all registries, accompanied by decreased AAIRs in overlapping region GBMs (-2.0% to -2.8% APC, P = 0.015). The AAIRs of GBMs in the parietal and occipital lobes remained stable. The AAIR of cerebellar GBMs increased according to CCR (APC +11.9%, P < 0.001). The AAIR of all gliomas, which includes all anatomical subsites, decreased (-0.5% to -0.8% APC, P = 0.034). Low-grade and anaplastic astrocytomas demonstrated decreased AAIRs in the majority of brain regions. Data from 3 major cancer registries demonstrate increased incidences of GBMs in the frontal lobe, temporal lobe, and cerebellum, despite decreased incidences in other brain regions. Although this may represent an effect of diagnostic bias, the incidence of both large and small tumors increased in these regions. The cause of these observed trends is unknown. It is interesting to note that despite a steadily and small decline in brain tumours over the measured period, tumours specifically in the frontal and temporal lobes have been increasing (the areas of the brain most exposed by mobile phone radiation). Of course, this does not demonstrate that phones are the cause of the increase, but it does demonstrate that further studies looking at the incidence rates of brain tumours should be careful to break down their findings by region, something missing from the majority of the recent papers that have declared that there is no upward trend in brain tumour rates.
3. N Bourthoumieu S et al, (July 2012) Study of p53 expression and post-transcriptional modifications after GSM-900 radiofrequency exposure of human amniotic cells, Bioelectromagnetics. 2012 Jul 5. doi: 10.1002/bem.21744. Epub ahead of print View Author's abstract conclusions View on Pubmed
The potential effects of radiofrequency (RF) exposure on the genetic material of cells are very important to determine since genome instability of somatic cells may be linked to cancer development. In response to genetic damage, the p53 protein is activated and can induce cell cycle arrest allowing more time for DNA repair or elimination of damaged cells through apoptosis. The objective of this study was to investigate whether the exposure to RF electromagnetic fields, similar to those emitted by mobile phones of the second generation standard, Global System for Mobile Communications (GSM), may induce expression of the p53 protein and its activation by post-translational modifications in cultured human cells. The potential induction of p53 expression and activation by GSM-900 was investigated after in vitro exposure of human amniotic cells for 24 h to average specific absorption rates (SARs) of 0.25, 1, 2, and 4 W/kg in the temperature range of 36.3-39.7 °C. The exposures were carried out using a wire-patch cell (WPC) under strictly controlled conditions of temperature. Expression and activation of p53 by phosphorylation at serine 15 and 37 were studied using Western blot assay immediately after three independent exposures of cell cultures provided from three different donors. Bleomycin-exposed cells were used as a positive control. According to our results, no significant changes in the expression and activation of the p53 protein by phosphorylation at serine 15 and 37 were found following exposure to GSM-900 for 24 h at average SARs up to 4 W/kg in human embryonic cells.
4. P Lu YS et al, (2012) Reactive Oxygen Species Formation and Apoptosis in Human Peripheral Blood Mononuclear Cell Induced by 900 MHz Mobile Phone Radiation, Oxid Med Cell Longev. 2012;2012:740280. Epub 2012 Jun 14 View Author's abstract conclusions View on Pubmed
We demonstrate that reactive oxygen species (ROS) plays an important role in the process of apoptosis in human peripheral blood mononuclear cell (PBMC) which is induced by the radiation of 900 MHz radiofrequency electromagnetic field (RFEMF) at a specific absorption rate (SAR) of ~0.4 W/kg when the exposure lasts longer than two hours. The apoptosis is induced through the mitochondrial pathway and mediated by activating ROS and caspase-3, and decreasing the mitochondrial potential. The activation of ROS is triggered by the conformation disturbance of lipids, protein, and DNA induced by the exposure of GSM RFEMF. Although human PBMC was found to have a self-protection mechanism of releasing carotenoid in response to oxidative stress to lessen the further increase of ROS, the imbalance between the antioxidant defenses and ROS formation still results in an increase of cell death with the exposure time and can cause about 37% human PBMC death in eight hours.
5. P Kitaoka K et al, (July 2012) Chronic exposure to an extremely low-frequency magnetic field induces depression-like behavior and corticosterone secretion without enhancement of the hypothalamic-pituitary-adrenal axis in mice, Bioelectromagnetics. 2012 Jul 2. doi: 10.1002/bem.21743. Epub ahead of print View Author's abstract conclusions View on Pubmed
An extremely low-frequency magnetic field (ELF-MF) is generated by power lines and household electrical devices. Many studies have suggested an association between chronic ELF-MF exposure and anxiety and/or depression. The mechanism of these effects is assumed to be a stress response induced by ELF-MF exposure. However, this mechanism remains controversial. In the present study, we investigated whether chronic ELF-MF exposure (intensity, 3 mT; total exposure, 200 h) affected emotional behavior and corticosterone synthesis in mice. ELF-MF-treated mice showed a significant increase in total immobility time in a forced swim test and showed latency to enter the light box in a light-dark transition test, compared with sham-treated (control) mice. Corticosterone secretion was significantly high in the ELF-MF-exposed mice; however, no changes were observed in the amount of the adrenocorticotropic hormone and the expression of genes related to stress response. Quantification of the mRNA levels of adrenal corticosteroid synthesis enzymes revealed a significant reduction in Cyp17a1 mRNA in the ELF-MF-exposed mice. Our findings suggest the possibility that high intensity and chronic exposure to ELF-MF induces an increase in corticosterone secretion, along with depression- and/or anxiety-like behavior, without enhancement of the hypothalamic-pituitary-adrenal axis. High ELF exposure study.
6. - Mattsson MO, Simko M, (June 2012) Is there a relation between extremely low frequency magnetic field exposure, inflammation and neurodegenerative diseases? A review of in vivo and in vitro experimental evidence., Toxicology. 2012 Jun 29. Epub ahead of print View Author's abstract conclusions View on Pubmed
Possible health consequences of exposure to extremely low frequency magnetic fields (ELF-MF) have received considerable interest during the last decades. One area of concern is neurodegenerative diseases (NDD), where epidemiological evidence suggests a correlation between MF exposure and Alzheimer's disease (AD). This review is focussing on animal and in vitro studies employing ELF-MF exposures to see if there is mechanistic support for any causal connection between NDD and MF-exposure. The hypothesis is that ELF-MF exposure can promote inflammation processes and thus influence the progression of NDD. A firm conclusion regarding this hypothesis is difficult to draw based on available studies, since there is a lack of experimental studies that have addressed the question of ELF-MF exposure and NDD. Furthermore, the heterogeneity of the performed studies regarding, e.g., the exposure duration, the flux density, the biological endpoint and the cell type and the time point of investigation is substantial and makes conclusions difficult to draw. Nevertheless, the investigated evidence from in vivo and in vitro studies suggest that short-term MF-exposure causes mild oxidative stress (modest ROS increases and changes in antioxidant levels) and possibly activates anti-inflammatory processes (decrease in pro-inflammatory and increase in anti-inflammatory cytokines). The few studies that specifically have investigated NDDs or NDD relevant end-points show that effects of exposure are either lacking or indicating positive effects on neuronal viability and differentiation. In both immune and NDD relevant studies, experiments with realistic long-term exposures are lacking. Importantly, consequences of a possible long-lasting mild oxidative stress are thus not investigated. In summary, the existing experimental studies are not adequate in answering if there is a causal relationship between MF-exposure and AD, as suggested in epidemiological studies. An interesting review paper that concludes that there are insufficient experiment data to confirm or deny the epidemioligical associations found with ''environment'' ELF EMFs and neurogenerative disease.
7. - Soderqvist F et al, (2012) Review of four publications on the Danish cohort study on mobile phone subscribers and risk of brain tumors, Rev Environ Health. 2012;27(1):51-8 View Author's abstract conclusions View on Pubmed
Since the International Agency for Research on Cancer recently classified radiofrequency electromagnetic fields, such as those emanating from mobile and cordless phones, as possibly carcinogenic to humans (group 2B), two additional reports relevant to the topic have been published. Both articles were new updates of a Danish cohort on mobile phone subscribers and concern the possible association between assumed use of mobile phones and risk of brain tumors. The aim of the present review is to reexamine all four publications on this cohort. In brief, publications were scrutinized, and in particular, if the authors made explicit claims to have either proved or disproved their hypothesis, such claims were reviewed in light of applied methods and study design, and in principle, the stronger the claims, the more careful our review. The nationwide Danish cohort study on mobile phone subscribers and risk of brain tumors, including at best 420,095 persons (58% of the initial cohort), is the only one of its kind. In comparison with previous investigations, i.e., case-control studies, its strength lies in the possibility to eliminate non-response, selection, and recall bias. Although at least non-response and recall bias can be excluded, the study has serious limitations related to exposure assessment. In fact, these limitations cloud the findings of the four reports to such an extent that render them uninformative at best. At worst, they may be used in a seemingly solid argument against an increased risk--as reassuring results from a large nationwide cohort study, which rules out not only non-response and recall bias but also an increased risk as indicated by tight confidence intervals. Although two of the most comprehensive case-control studies on the matter both have methodological limitations that need to be carefully considered, type I errors are not the only threats to the validity of studies on this topic--the Danish cohort study is a textbook example of that. This is a particularly scathing review of the quality of the data in the Danish Cohort Study, and by inference the papers published from that dataset.
8. N Jin YB et al, (July 2012) Effects of Simultaneous Combined Exposure to CDMA and WCDMA Electromagnetic Field on Immune Functions in Rats, Int J Radiat Biol. 2012 Jul 12. Epub ahead of print View Author's abstract conclusions View on Pubmed
Despite the importance of the immune system in defending the body against infection and cancer, little research on the possible effects of radiofrequency electromagnetic field (RF-EMF) signals on immune functions exists, and, in the case of simultaneous combined exposure of RF-EMF, to the best of our knowledge no work has been done. The aim of this study was to assess the effect of simultaneous exposure to two types of RF-EMF signals, single code division multiple access (CDMA) and wideband code division multiple access (WCDMA) signals on the immune system of rats. Male Sprague-Dawley rats were exposed to RF-EMF for 45 min/day, 5 days/week for up to 8 weeks. The whole body average specific absorption rate (SAR) of CDMA or WCDMA was 2.0 W/kg. Every 2 weeks after the experiment began, 20 rats were autopsied. Blood hematology, subtype population of splenocytes and cytokine production or mRNA expressions, interleukin (IL)-6, tumor necrosis factor (TNF)-a, IL-1β, interferon (IFN)-α and transforming growth factor (TGF)-β from the splenocytes or IL-6, TNF-a, and immunoglobulin (Ig) of IgG and IgM from blood serum, were examined. The results suggest that 8-week exposure to CDMA (849 MHz) and WCDMA (1.95 GHz) RF simultaneously at 2.0 W/kg each for 45-min RF-EMF exposure (total, 4 W/kg) did not affect these immune parameters. The present experiments suggest that simultaneous combined exposure of CDMA and WCDMA with total SAR dose of 4.0 W/kg for 45 min/day for 8 weeks, which is a relatively high SAR level compared to the exposure levels for the human system recommended by International Commission on Non-Ionizing Radiation Protection (ICNIRP, 0.4W/kg for whole body exposure levels and 2.0W/kg for local exposure levels of general public), did not have any detectable effects on immune function in rats.
9. P Avci B et al, (July 2012) Oxidative stress induced by 1.8 Ghz radio frequency electromagnetic radiation and effects of the garlic extract in rats, Int J Radiat Biol. 2012 Jul 12. Epub ahead of print View Author's abstract conclusions View on Pubmed
We aimed to study the oxidative damage induced by radiofrequency electromagnetic radiation (RF-EMR) emitted by mobile telephones and the protective effect of garlic extract used as an anti-oxidant against this damage. Materials and methods: A total of 66 albino Wistar rats were divided into 3 groups. The 1(st) group of rats was given 1.8 GHz, 0.4 W/kg specific absorption rate (SAR) for 1 hour a day for 3 weeks. The 2(nd) group was given 500 mg/kg garlic extract in addition to RF-EMR. The 3(rd) group of rats was used as the control group. At the end of the study, blood and brain tissue samples were collected from the rats. Results: After the RF-EMR exposed, the advanced oxidation protein product (AOPP) levels of brain tissue increased compared with the control group (p < 0.001). Garlic administration accompanying the RF-EMR, on the other hand, significantly reduced AOPP levels in brain tissue (p < 0.001). The serum nitric oxide (NO) levels significantly increased both in the 1(st) and the 2(nd) group (p < 0.001). However, in the group for which garlic administration accompanied that of RF-EMR, there was no difference in serum NO levels compared with the RF-EMR exposed group (p > 0.05). There was no significant difference among the groups with respect to malondialdehyde (MDA) levels in brain tissue and blood samples (p > 0.05). Similarly, no difference was detected among the groups regarding serum paroxonase (PON) levels (p > 0.05). We did not detect any PON levels in the brain tissue. The exposure of RF-EMR similar to 1.8 GHz Global system for mobile communication (GSM) leads to protein oxidation in brain tissue and an increase in serum NO. We observed that garlic administration reduced protein oxidation in brain tissue and that it did not have any effects on serum NO levels.
10. - Miller G et al, (February 2012) The heritability and genetic correlates of mobile phone use: a twin study of consumer behavior, Twin Res Hum Genet. 2012 Feb;15(1):97-106 View Author's abstract conclusions View on Pubmed
There has been almost no overlap between behavior genetics and consumer behavior research, despite each field's importance in understanding society. In particular, both have neglected to study genetic influences on consumer adoption and usage of new technologies -- even technologies as important as the mobile phone, now used by 5.8 out of 7.0 billion people on earth. To start filling this gap, we analyzed self-reported mobile phone use, intelligence, and personality traits in two samples of Australian teenaged twins (mean ages 14.2 and 15.6 years), totaling 1,036 individuals. ACE modeling using Mx software showed substantial heritabilities for how often teens make voice calls (.60 and .34 in samples 1 and 2, respectively) and for how often they send text messages (.53 and. 50). Shared family environment - including neighborhood, social class, parental education, and parental income (i.e., the generosity of calling plans that parents can afford for their teens) -- had much weaker effects. Multivariate modeling based on cross-twin, cross-trait correlations showed negative genetic correlations between talking/texting frequency and intelligence (around -.17), and positive genetic correlations between talking/texting frequency and extraversion (about .20 to .40). Our results have implications for assessing the risks of mobile phone use such as radiofrequency field (RF) exposure and driving accidents, for studying adoption and use of other emerging technologies, for understanding the genetic architecture of the cognitive and personality traits that predict consumer behavior, and for challenging the common assumption that consumer behavior is shaped entirely by culture, media, and family environment.
11. P Zhao LY et al, (March 2012) Effects of extremely low frequency electromagnetic radiation on cardiovascular system of workers, Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2012 Mar;30(3):194-5 View Author's abstract conclusions View on Pubmed
To observe the exposure levels of extremely low frequency electromagnetic fields in workplaces and to analyze the effects of extremely low frequency electromagnetic radiation on cardiovascular system of occupationally exposed people. Intensity of electromagnetic fields in two workplaces (control and exposure groups) was detected with EFA-300 frequency electromagnetic field strength tester, and intensity of the noise was detected with AWA5610D integral sound level. The information of health physical indicators of 188 controls and 642 occupationally exposed workers was collected. Data were analyzed by SPSS17.0 statistic software. The intensity of electric fields and the magnetic fields in exposure groups was significantly higher than that in control group (P < 0.05), but there was no significant difference of noise between two workplaces (P > 0.05). The results of physical examination showed that the abnormal rates of HCY, ALT, AST, GGT, ECG in the exposure group were significantly higher than those in control group (P < 0.05). There were no differences of sex, age, height, weight between two groups (P > 0.05). Exposure to extremely low frequency electromagnetic radiation may have some effects on the cardiovascular system of workers.
12. P Xu XR et al, (March 2012) The effects of extremely low frequency electromagnetic field exposure on the pH of the adult male semen and the motoricity parameters of spermatozoa in vitro, Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2012 Mar;30(3):178-80 View Author's abstract conclusions View on Pubmed
To study the effects of 50-Hz extremely low frequency electromagnetic field (ELF-EMF) exposure on the pH of the adult male semen and the motoricity and motoricity parameters of spermatozoa. Healthy adult male fresh semen was exposed to a 50-Hz EMF at 0.4 mT for 15, 30 and 60 min, respectively. The pH value of the semen, the motoricity and motoricity parameter of spermatozoa were detected and recorded in real time using the WLJY-9000 pattern chromatic color spermatozoa quality detection system. Compared with parallel control group, the exposure of adult male fresh semen to a 50-Hz EMF at 0.4 mT for 15 min or 60 min could decrease significantly the motoricity (spermatozoa with a + b lever) and the activity ratio (spermatozoa with a + b + c lever)(P < 0.01). However, there were no significant differences of motoricity and the activity ratio between exposure group and control group (P > 0.05), and after exposure to a 50-Hz. EMF for 30 min the motoricity and the activity ratio of exposure group were inhibited, as compared with control group (P < 0.01 or P < 0.05). The pH value of the semen was not obvious changed (P > 0.05) when semen was exposed to a 50-Hz EMF of 0.4 mT for 15, 30 and 60 min. In present experiment, it is suggested that the exposure of adult male fresh semen to a 50-Hz EMF in vitro could inhibit the motoricity and the activity ratio, but not affect the pH value of the semen within 60 min.
13. P Arendash GW et al, (2012) Electromagnetic treatment to old Alzheimer's mice reverses beta-amyloid deposition, modifies cerebral blood flow, and provides selected cognitive benefit, PLoS One. 2012;7(4):e35751. Epub 2012 Apr 25 View Author's abstract conclusions View on Pubmed
Few studies have investigated physiologic and cognitive effects of ''long-term'' electromagnetic field (EMF) exposure in humans or animals. Our recent studies have provided initial insight into the long-term impact of adulthood EMF exposure (GSM, pulsed/modulated, 918 MHz, 0.25-1.05 W/kg) by showing 6+ months of daily EMF treatment protects against or reverses cognitive impairment in Alzheimer's transgenic (Tg) mice, while even having cognitive benefit to normal mice. Mechanistically, EMF-induced cognitive benefits involve suppression of brain β-amyloid (Aβ) aggregation/deposition in Tg mice and brain mitochondrial enhancement in both Tg and normal mice. The present study extends this work by showing that daily EMF treatment given to very old (21-27 month) Tg mice over a 2-month period reverses their very advanced brain Aβ aggregation/deposition. These very old Tg mice and their normal littermates together showed an increase in general memory function in the Y-maze task, although not in more complex tasks. Measurement of both body and brain temperature at intervals during the 2-month EMF treatment, as well as in a separate group of Tg mice during a 12-day treatment period, revealed no appreciable increases in brain temperature (and no/slight increases in body temperature) during EMF ''ON'' periods. Thus, the neuropathologic/cognitive benefits of EMF treatment occur without brain hyperthermia. Finally, regional cerebral blood flow in cerebral cortex was determined to be reduced in both Tg and normal mice after 2 months of EMF treatment, most probably through cerebrovascular constriction induced by freed/disaggregated Aβ (Tg mice) and slight body hyperthermia during ''ON'' periods. These results demonstrate that long-term EMF treatment can provide general cognitive benefit to very old Alzheimer's Tg mice and normal mice, as well as reversal of advanced Aβ neuropathology in Tg mice without brain heating. Results further underscore the potential for EMF treatment against AD.
14. P Atasoy HI et al, (March 2012) Immunohistopathologic demonstration of deleterious effects on growing rat testes of radiofrequency waves emitted from conventional Wi-Fi devices, J Pediatr Urol. 2012 Mar 30. Epub ahead of print View Author's abstract conclusions View on Pubmed
To investigate effects on rat testes of radiofrequency radiation emitted from indoor Wi-Fi Internet access devices using 802.11.g wireless standards. Ten Wistar albino male rats were divided into experimental and control groups, with five rats per group. Standard wireless gateways communicating at 2.437 GHz were used as radiofrequency wave sources. The experimental group was exposed to radiofrequency energy for 24 h a day for 20 weeks. The rats were sacrificed at the end of the study. Intracardiac blood was sampled for serum 8-hydroxy-2'-deoxyguanosine levels. Testes were removed and examined histologically and immunohistochemically. Testis tissues were analyzed for malondialdehyde levels and prooxidant-antioxidant enzyme activities. We observed significant increases in serum 8-hydroxy-2'-deoxyguanosine levels and 8-hydroxyguanosine staining in the testes of the experimental group indicating DNA damage due to exposure (p < 0.05). We also found decreased levels of catalase and glutathione peroxidase activity in the experimental group, which may have been due to radiofrequency effects on enzyme activity (p < 0.05). These findings raise questions about the safety of radiofrequency exposure from Wi-Fi Internet access devices for growing organisms of reproductive age, with a potential effect on both fertility and the integrity of germ cells.
15. P Bellieni CV et al, (2012) Exposure to electromagnetic fields from laptop use of ''laptop'' computers, Arch Environ Occup Health. 2012;67(1):31-6 View Author's abstract conclusions View on Pubmed
Portable computers are often used at tight contact with the body and therefore are called ''laptop.'' The authors measured electromagnetic fields (EMFs) laptop computers produce and estimated the induced currents in the body, to assess the safety of laptop computers. The authors evaluated 5 commonly used laptop of different brands. They measured EMF exposure produced and, using validated computerized models, the authors exploited the data of one of the laptop computers (LTCs) to estimate the magnetic flux exposure of the user and of the fetus in the womb, when the laptop is used at close contact with the woman's womb. In the LTCs analyzed, EMF values (range 1.8-6 µT) are within International Commission on Non-Ionizing Radiation (NIR) Protection (ICNIRP) guidelines, but are considerably higher than the values recommended by 2 recent guidelines for computer monitors magnetic field emissions, MPR II (Swedish Board for Technical Accreditation) and TCO (Swedish Confederation of Professional Employees), and those considered risky for tumor development. When close to the body, the laptop induces currents that are within 34.2% to 49.8% ICNIRP recommendations, but not negligible, to the adult's body and to the fetus (in pregnant women). On the contrary, the power supply induces strong intracorporal electric current densities in the fetus and in the adult subject, which are respectively 182-263% and 71-483% higher than ICNIRP 98 basic restriction recommended to prevent adverse health effects. Laptop is paradoxically an improper site for the use of a LTC, which consequently should be renamed to not induce customers towards an improper use.
16. P Bhargava S et al, (August 2012) Effect of handheld mobile phone use on parotid gland salivary flow rate and volume, Oral Surg Oral Med Oral Pathol Oral Radiol. 2012 Aug;114(2):200-6 View Author's abstract conclusions View on Pubmed
Handheld mobile phones emit nonionizing electromagnetic radiations and generate heat during use which can be absorbed by the adjacent tissues. This study observed functional and volumetric changes in the parotid glands associated with mobile phone use. Unstimulated parotid salivary flow rate was measured bilaterally in 142 individuals divided into 2 groups of heavy users and control subjects using a modified Schirmer test. Bilateral parotid ultrasonography was performed to evaluate gland volume. Variation and correlation tests were used to statistically analyze the results. A significant increase in salivary flow rate along with increased blood flow rate and volume of the parotid glands of the side where mobile phones are frequently placed was observed in the heavy user group. Heavy users of mobile phones demonstrated increased salivary flow rate, blood flow rate, and volume of parotid glands.
17. - Blank M, Goodman RM, (June 2012) Electromagnetic fields and health: DNA-based dosimetry, Electromagn Biol Med. 2012 Jun 7. Epub ahead of print View Author's abstract conclusions View on Pubmed
We propose a biologically based measure of EMF radiation to replace the energy-based ''specific absorption rate'' (SAR). A wide range of EMF frequencies has been linked to an increased risk of cancer. The SAR value used to measure the EMF dose and set the safety standard in the radiofrequency (RF) range fails as a standard for predicting cancer risk in the ELF power frequency range. Because cancers are believed to arise from mutations in DNA, changes in DNA induced by interaction with EMF could be a better measure of the biologically effective dose in both frequency ranges. The changes can be measured by transcriptional alterations and/or translational changes in specific proteins. Because ionizing radiation also causes DNA damage, a biologically based standard related to stimulation of DNA could apply over a much wider range of the electromagnetic spectrum. A safety standard for exposure to a wide range of non ionizing frequencies can be based on the documented changes in DNA biochemistry that arise from interactions with EMF.
18. P Chen G et al, (April 2012) Using model organism Saccharomyces cerevisiae to evaluate the effects of ELF-MF and RF-EMF exposure on global gene expression, Bioelectromagnetics. 2012 Apr 9. doi: 10.1002/bem.21724. Epub ahead of print View Author's abstract conclusions View on Pubmed
The potential health hazard of exposure to electromagnetic fields (EMF) continues to cause public concern. However, the possibility of biological and health effects of exposure to EMF remains controversial and their biophysical mechanisms are unknown. In the present study, we used Saccharomyces cerevisiae to identify genes responding to extremely low frequency magnetic fields (ELF-MF) and to radiofrequency EMF (RF-EMF) exposures. The yeast cells were exposed for 6 h to either 0.4 mT 50 Hz ELF-MF or 1800 MHz RF-EMF at a specific absorption rate of 4.7 W/kg. Gene expression was analyzed by microarray screening and confirmed using real-time reverse transcription-polymerase chain reaction (RT-PCR). We were unable to confirm microarray-detected changes in three of the ELF-MF responsive candidate genes using RT-PCR (P > 0.05). On the other hand, out of the 40 potential RF-EMF responsive genes, only the expressions of structural maintenance of chromosomes 3 (SMC3) and aquaporin 2 (AQY2 (m)) were confirmed, while three other genes, that is, halotolerance protein 9 (HAL9), yet another kinase 1 (YAK1) and one function-unknown gene (open reading frame: YJL171C), showed opposite changes in expression compared to the microarray data (P < 0.05). In conclusion, the results of this study suggest that the yeast cells did not alter gene expression in response to 50 Hz ELF-MF and that the response to RF-EMF is limited to only a very small number of genes. The possible biological consequences of the gene expression changes induced by RF-EMF await further investigation.
19. P Christ A et al, (June 2012) Exposure of the Human Body to Professional and Domestic Induction Cooktops Compared to the Basic Restrictions, Bioelectromagnetics. 2012 Jun 1. doi: 10.1002/bem.21739. Epub ahead of print View Author's abstract conclusions View on Pubmed
We investigated whether domestic and professional induction cooktops comply with the basic restrictions defined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Based on magnetic field measurements, a generic numerical model of an induction cooktop was derived in order to model user exposure. The current density induced in the user was simulated for various models and distances. We also determined the exposure of the fetus and of young children. While most measured cooktops comply with the public exposure limits at the distance specified by the International Electrotechnical Commission (standard IEC 62233), the majority exceeds them at closer distances, some of them even the occupational limits. The maximum current density in the tissue of the user significantly exceeds the basic restrictions for the general public, reaching the occupational level. The exposure of the brains of young children reaches the order of magnitude of the limits for the general public. For a generic worst-case cooktop compliant with the measurement standards, the current density exceeds the 1998 ICNIRP basic restrictions by up to 24?dB or a factor of 16. The brain tissue of young children can be overexposed by 6?dB or a factor of 2. The exposure of the tissue of the central nervous system of the fetus can exceed the limits for the general public if the mother is exposed at occupational levels. This demonstrates that the methodology for testing induction cooktops according to IEC 62233 contradicts the basic restrictions. This evaluation will be extended considering the redefined basic restrictions proposed by the ICNIRP in 2010.
20. P Fedrowitz M, Loscher W, (May 2012) Gene expression in the mammary gland tissue of female Fischer 344 and Lewis rats after magnetic field exposure (50 Hz, 100 uT) for 2 weeks, Int J Radiat Biol. 2012 May;88(5):425-9. Epub 2012 Feb 28 View Author's abstract conclusions View on Pubmed
The issue of whether exposure to environmental power-frequency magnetic fields (MF) has impact on breast cancer development still remains equivocal. Previously, we observed rat strain differences in the MF response of breast tissue, so that the genetic background plays a role in MF effects. The present experiment aimed to elucidate candidate genes involved in MF effects by comparison of MF-susceptible Fischer 344 (F344) rats and MF-insensitive Lewis rats. Female F344 and Lewis rats were exposed to MF (50 Hz, 100 µT) for two weeks, and a whole genome microarray analysis in the mammary gland tissue was performed. A remarkably decreased a-amylase gene expression, decreases in carbonic anhydrase 6 and lactoperoxidase, both relevant for pH regulation, and an increased gene expression of cystatin E/M, a tumor suppressor, were observed in MF-exposed F344, but not in Lewis rats. The MF-exposed F344 breast tissue showed alterations in gene expression, which were absent in Lewis and may therefore be involved in the MF-susceptibility of F344. Notably α-amylase might serve as a promising target to study MF effects, because first experiments indicate that MF exposure alters the functionality of this enzyme in breast tissue.
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