Effects of exposure to 2100 MHz GSM-like radiofrequency electromagnetic field on auditory system of rats / Efeitos da exposição a um campo eletromagnético na radiofrequência de 2100 MHz, similar ao sistema GSM, no sistema auditivo de ratos

Abstract Introduction: The use of mobile phones has become widespread in recent years. Although beneficial from the communication viewpoint, the electromagnetic fields generated by mobile phones may cause unwanted biological changes in the human body. Objective: In this study, we aimed to evaluate the effects of 2100 MHz Global System for Mobile communication (GSM-like) electromagnetic field, generated by an electromagnetic fields generator, on the auditory system of rats by using electrophysiological, histopathologic and immunohistochemical methods. Methods: Fourteen adult Wistar albino rats were included in the study. The rats were divided randomly into two groups of seven rats each. The study group was exposed continuously for 30 days to a 2100 MHz electromagnetic fields with a signal level (power) of 5.4 dBm (3.47 mW) to simulate the talk mode on a mobile phone. The control group was not exposed to the aforementioned electromagnetic fields. After 30 days, the Auditory Brainstem Responses of both groups were recorded and the rats were sacrificed. The cochlear nuclei were evaluated by histopathologic and immunohistochemical methods. Results: The Auditory Brainstem Responses records of the two groups did not differ significantly. The histopathologic analysis showed increased degeneration signs in the study group (p = 0.007). In addition, immunohistochemical analysis revealed increased apoptotic index in the study group compared to that in the control group (p = 0.002). Conclusion: The results support that long-term exposure to a GSM-like 2100 MHz electromagnetic fields causes an increase in neuronal degeneration and apoptosis in the auditory system.

Resumo Introdução: O uso de telefones celulares tornou-se generalizado nos últimos anos. Embora benéfico do ponto de vista da comunicação, os campos eletromagnéticos gerados por celulares pode causar alterações biológicas indesejáveis no corpo humano. Objetivo: Nesse estudo, o objetivo foi avaliar os efeitos do campo eletromagnético na frequência de 2.100 MHz, similar à modulação do Sistema Global para Comunicações Móveis, produzido por um gerador de campo eletromagnético, sobre o sistema auditivo de ratos usando os métodos eletrofisiológico, histopatológico e imunohistoquímico. Método: Foram incluídos no estudo catorze adultos ratos albinos Wistar. Os ratos foram divididos aleatoriamente em dois grupos de sete animais cada. O grupo de estudo foi exposto continuamente por 30 dias a um campo eletromagnético em 2100 MHz com um nível de sinal (potência) de 5,4 dBm (3,47 miliwatts) para simular o modo de conversação em um celular. O grupo controle não foi exposto ao campo eletromagnético acima mencionado. Após 30 dias, o potencial evocado auditivo de tronco encefálico de ambos os grupos foi gravado e os ratos foram sacrificados. Os núcleos cocleares foram avaliados pelos métodos histopatológico e imunohistoquímico. Resultados: Os registros do potencial evocado auditivo de tronco encefálico dos dois grupos não diferiram significativamente. A análise histopatológica mostrou aumento dos sinais de degeneração no grupo de estudo (p = 0,007). Além disso, a análise imuno-histoquímica revelou aumento do índice de apoptose no grupo de estudo em comparação com o grupo controle (p = 0,002). Conclusão: Os resultados confirmam que a exposição a longo prazo a um campo eletromagnético em 2100 MHz similar à modulação do sistema global para comunicações móveis causa um aumento na degeneração neuronal e apoptose no sistema auditivo.

New concept for treating female stress urinary incontinence with radiofrequency

ABSTRACT Purpose: To evaluate the clinical response and adverse effects of radiofrequency on the urethral meatus in the treatment of stress urinary incontinence in women. Materials and Methods: This phase one study included ten women with Stress Urinary Incontinence (SUI). The evaluation consisted of 1 hour Pad tests to quantify urine loss and to assess the degree of procedure satisfaction by using the Likert scale. To evaluate safety, we observed the number of referred side effects. Results: Average age was 53.10 years±7.08 years. In assessing the final Pad Test, 70% showed a reduction and 30% a worsening of urinary loss. Using the Pad Test one month later, there was a reduction in all patients (p=0.028). The degree of satisfaction was 90% and no side effects have been observed. One patient reported burning sensation. Conclusion: The treatment of SUI with radiofrequency on the urethral meatus has no adverse effects, being a low risk method that reduces urinary loss in women. However, to increase the validity of the study, larger clinical trials are warranted.

Tinnitus and cell phones: the role of electromagnetic radiofrequency radiation / Zumbido e telefones celulares: o papel da radiação eletromagnética de radiofrequência

ABSTRACT INTRODUCTION: Tinnitus is a multifactorial condition and its prevalence has increased on the past decades. The worldwide progressive increase of the use of cell phones has exposed the peripheral auditory pathways to a higher dose of electromagnetic radiofrequency radiation (EMRFR). Some tinnitus patients report that the abusive use of mobiles, especially when repeated in the same ear, might worsen ipsilateral tinnitus. OBJECTIVE: The aim of this study was to evaluate the available evidence about the possible causal association between tinnitus and exposure to electromagnetic waves. METHODS: A literature review was performed searching for the following keywords: tinnitus, electromagnetic field, mobile phones, radio frequency, and electromagnetic hypersensitivity. We selected 165 articles that were considered clinically relevant in at least one of the subjects. RESULTS: EMRFR can penetrate exposed tissues and safety exposure levels have been established. These waves provoke proved thermogenic effects and potential biological and genotoxic effects. Some individuals are more sensitive to electromagnetic exposure (electrosensitivity), and thus, present earlier symptoms. There may be a common pathophysiology between this electrosensitivity and tinnitus. CONCLUSION: There are already reasonable evidences to suggest caution for using mobile phones to prevent auditory damage and the onset or worsening of tinnitus.

RESUMO INTRODUÇÃO: Zumbido é uma condição multifatorial cuja prevalência vem aumentando nas últimas décadas. Em todo o mundo, o aumento progressivo do uso de telefones celulares tem exposto as orelhas a uma maior carga de radiação eletromagnética de radiofrequência (REM-RF). Alguns pacientes com zumbido referem que o uso excessivo do telefone celular, especialmente quando sempre na mesma orelha, é um fator de piora do zumbido ipsilateral. OBJETIVO: O objetivo deste trabalho foi avaliar as evidências disponíveis sobre a possível associação causal entre zumbido e exposição a ondas eletromagnéticas. MÉTODO: Foi realizada uma revisão de literatura com palavras-chave como: tinnitus, electromagnectic field, cellular phone, radiofrequency, electromagnectic hypersensitivity. Foram selecionados 165 artigos com maior relevância clínica em pelo menos um dos assuntos. RESULTADOS: As REM-RF podem penetrar tecidos expostos e existem níveis seguros de exposição. Apresentam efeitos termogênicos comprovados e potenciais efeitos biológicos e genotóxicos. Alguns indivíduos são mais sensíveis à exposição eletromagnética (eletrossensibilidade) e, portanto, adquirem sintomas precocemente. A fisiopatologia da eletrossensibilidade pode ser semelhante à do zumbido. CONCLUSÃO: Consideramos que há evidências suficientes que sugerem maior cautela para o uso desses aparelhos e assim prevenir lesões na via auditiva e o aparecimento/agravamento do zumbido.

Exposição a radiações eletromagnéticas não ionizantes da telefonia celular e sintomas psiquiátricos / Exposición a la radiación electromagnética no ionizante de la telefonía móvil y síntomas psiquiátricos / Exposure to non-ionizing electromagnetic radiation from mobile telephony and the association with psychiatric symptoms

Resumo O objetivo desse estudo foi investigar a associação entre exposição a radiações eletromagnéticas não ionizantes da estação radiobase de telefonia celular e sintomas à saúde. Em um estudo transversal realizado em Salvador, Bahia, Brasil, entrevistaram-se 440 indivíduos. Queixas e diagnósticos psiquiátricos constituíram as variáveis dependentes e a distância do domicílio para estação radiobase foi considerada a variável independente principal. Realizou-se análise de regressão logística hierarquizada para avaliação de confundimento e efeito. Observou-se associação entre sintomas psiquiátricos e residir próximo à estação radiobase e formas de uso do telefone celular (sinal de cobertura fraco, perto do corpo, dois ou mais chips e nunca desligar o celular quando dorme) e com uso de outros eletroeletrônicos. Concluiu-se que a exposição à radiação eletromagnética não ionizante de telefonia celular e a outros eletroeletrônicos foi associada aos sintomas psiquiátricos independente do sexo, escolaridade e tabagismo. Recomenda-se a adoção de medidas precaucionárias no sentido de se reduzir este tipo de exposição.

Resumen El objetivo de este estudio fue investigar la asociación entre la exposición a la radiación electromagnética no ionizante de una estación base telefonía móvil y sus efectos sobre la salud. Se trata de un estudio transversal en Salvador, Bahía, Brasil, donde se entrevistaron a 440 personas. Las quejas y diagnósticos psiquiátricos fueron las variables dependientes y la distancia del hogar a la estación base se consideró como la variable independiente principal. Se realizó un análisis de regresión logística jerárquica para evaluar la confusión y modificación de los efectos. Se observó una asociación entre los efectos psiquiátricos y residir cerca de una estación base y formas de uso del teléfono celular (débil cobertura de la señal, cerca del cuerpo dos o más chips y nunca apagar el teléfono cuando se duerme) y uso de otros aparatos electrónicos. Se concluyó que la exposición a radiación no ionizante de la telefonía móvil y otros aparatos electrónicos se asoció con efectos psiquiátricos, independiente de sexo, la educación y el tabaquismo. Se recomienda la adopción de medidas de precaución, con el fin de reducir la exposición.

Abstract The aim of this study was to investigate the association between exposure to non-ionizing electromagnetic radiation from mobile phone base stations and psychiatric symptoms. In a cross-sectional study in Salvador, Bahia State, Brazil, 440 individuals were interviewed. Psychiatric complaints and diagnoses were the dependent variables and distance from the individual’s residence to the base station was considered the main independent variable. Hierarchical logistic regression analysis was conducted to assess confounding. An association was observed between psychiatric symptoms and residential proximity to the base station and different forms of mobile phone use (making calls with weak signal coverage, keeping the mobile phone close to the body, having two or more chips, and never turning off the phone while sleeping), and with the use of other electronic devices. The study concluded that exposure to electromagnetic radiation from mobile phone base stations and other electronic devices was associated with psychiatric symptoms, independently of gender, schooling, and smoking status. The adoption of precautionary measures to reduce such exposure is recommended.

Exposure of pregnant rats to shortwave electromagnetic athermal radiation does not adversely affect their fetuses / Exposição de ratas prenhes a ondas curtas de radiação eletromagnética atérmica não afeta adversamente os seus fetos

BACKGROUND: The aim of this study was to determine whether shortwave electromagnetic radiation in pulsed mode with a frequency of 45 Hz, promotes teratogenic changes, stillbirths and changes in organ weight at birth in the fetuses of pregnant rats exposed to this radiation. METHOD: Ten black Macole pregnant female rats were studied, 5 in a test group, subjected to electromagnetic radiation with an average power of 4.5 W for 15 minutes, on a daily basis, during the entire period of pregnancy and 5 in a control group that was not exposed to radiation. At day 21, the animals were euthanized for analysis of fetuses. To assess the thermal effect of the radiation the abdominal temperature was measured before and after application, together with prevailing ambient temperature. The fetuses were evaluated through the Galant reflex to assess the existence of stillbirths. The fetuses were removed and weighed; through a midline laparotomy their hearts, stomachs, kidneys and livers were excised and weighed, wet and dry. Twenty-nine fetuses were harvested in the control group and 59 in the test group, with no cases of stillbirth, teratogenesis or malformation of internal organs. RESULTS: The analysis found no differences in birthweight and weight of dehydrated organs when compared to the control group. CONCLUSION: The results in our findings suggest that exposure to shortwave therapy without significant heat buildup, does not lead to teratogenic changes and did not affect the mass and weight of dehydrated internal organs.

RESUMO OBJETIVO: O objetivo deste estudo foi determinar se a radiação eletromagnética de ondas curtas em modo pulsado com uma frequência de 45 Hz, promove mudanças teratogênicos, natimortos, mudanças no peso do órgão ao nascimento em fetos de ratas grávidas expostas a essa radiação. METODO: Foram estudados dez ratas grávidas da raça Marcole, cinco num grupo teste, submetidas a radiação eletromagnética com uma potência média de 4,5W, durante 15 minutos, diariamente, durante todo o período da gravideze cinco num grupo controle, não expostas a radiação. No 21º dia, os animais foram sacrificados para análise dos fetos. Para avaliar o efeito da radiação térmica, a temperatura abdominal foi medida antes e depois da aplicação, em conjunto com a temperatura ambiente prevalente. Os fetos foram submetidos ao reflexo de Galant para avaliara existênciade natimortos. Os fetos foram removidos e pesados; através de uma laparotomia mediana seus corações, estômagos, rins e fígados foram extirpados e pesados, frescose secos. RESULTADOS: Vinte e nove fetos foram colhidos no grupo controle e 59 no grupo de teste, sem casos de natimortos, teratogênese ou malformação dos órgãos internos. A análise não encontrou diferenças no peso ao nascer e peso de órgãos desidratados quando comparados com o grupo controle. CONCLUSÃO: Os resultados sugerem que a exposição a terapia de ondas curtas, sem o acúmulo significativo de calor, não levou a alterações teratogênicos e não afetou o peso dos fetos ou o peso dos órgãos internos desidratados.

Cell phone radiation effects on cytogenetic abnormalities of oral mucosal cells

The aim of this study was to evaluate the effects of exposure to cell phone electromagnetic radiation on the frequency of micronuclei, broken eggs cells, binucleated cells, and karyorrhexis in epithelial cells of the oral mucosa. The sample was composed of 60 cell phone users, who were non-smokers and non-drinkers, and had no clinically visible oral lesions. Cells were obtained from anatomical sites with the highest incidence of oral cancer: lower lip, border of the tongue, and floor of the mouth. The Feulgen reaction was used for quantification of nuclear anomalies in 1,000 cells/slide. A slightly increase in the number of micronucleated cells in the lower lip and in binucleated cells on the floor of the mouth was observed in individuals who used their phones > 60 minutes/week. The analysis also revealed an increased number of broken eggs in the tongue of individuals owning a cell phone for over eight years. Results suggest that exposure to electromagnetic waves emitted by cell phones can increase nuclear abnormalities in individuals who use a cell phone for more than 60 minutes per week and for over eight years. Based on the present findings, we suggest that exposure to electromagnetic radiation emitted by cell phones may interfere with the development of metanuclear anomalies. Therefore, it is demonstrated that, despite a significant increase in these anomalies, the radiation emitted by cell phones among frequent users is within acceptable physiological limits.

Efectos de la radiación electromagnética no ionizante sobre lasalud y el caso específico de los efectos en la salud humana de la telefonía celular / Health effects of non-ionizing electromagnetic radiation, and the specific case of the effects of mobile telephony

Los efectos en salud de la radiación electromagnética ionizante son bien conocidos; sin embargo hay menos reconocimiento de los efectos en salud causados por exposición a radiación electromagnética no ionizante. La primera parte del presente trabajo se refiere a los efectos en salud de las radiaciones electromagnéticas no ionizantes, independiente de su origen, puesto que no hay diferencias apreciables entre los efectos producidos por los diversos tipos de radiación electromagnética no ionizante y por lo tanto, son también válidas para aquellas emitidas por la telefonía celular. Se describe una asociación estadísticamente significativa de varias enfermedades a radiación electromagnética de frecuencia baja (ELF) proveniente de tendidos o transformadores de alta tensión, radiación electromagnética ELF del tendido eléctrico domiciliario y de artefactos electrodomésticos, exposición ocupacional a radiación electromagnética principalmente ELF, y radiación electromagnética de radiofrecuencia (RF) proveniente de antenas de transmisión de televisión. A continuación se analizan los efectos ya demostrados de la telefonía celular (los teléfonos y sus antenas repetidoras). Luego se analizan los grados de certeza de un estudio del Estado de California (USA) para relacionar las diversas enfermedades causadas por radiación electromagnética no ionizante. Este estudio confirmó la alta o mediana probabilidad de una relación causa-efecto de la radiación electromagnética con las siguientes enfermedades: leucemia en adultos y niños, cáncer cerebral en adultos y niños, cáncer de mama femenino y masculino, abortos espontáneos, suicidio, enfermedad de Alzheimer, esclerosis lateral amiotrófica y enfermedades cardiovasculares incluyendo infarto del miocardio. Se describen cuales son estas enfermedades de acuerdo al origen de estas radiaciones y se analizan cuales pueden ser los mecanismos biológicos que determinan la génesis de éstas...

The health effects of ionizing electromagnetic radiation are well known; neverthless there exist less recognition on the health effects of exposure to non-ionizing electromagnetic radiation. The first part of the present report refers to health effects of non-ionizing electromagnetic radiation, independently of its origin, since there are not important differences among effects caused by the different kind of non-ionizing radiations, therefore, they are valid for those emmited by the mobile telephony. A statistically significant association is described among various diseases and extremely low frequency electromagnetic radiation (ELF) from high tension electric conductors or transformers, intradomiciliary electric lines or electrodomestic appliances, occupational exposure to electromagnetic fields, mainly ELF, and radiofrequency (RF) electromagnetic radiation from television transmission. Already demonstrated effects of mobile telephony (cellular telephones and their antenas). The degrees of certainty from a study of the State of California (USA) is analyzed to relate various diseases caused by non-ionizing radiation. This study confirmed high or moderate probability of a cause-effect relationship for adult and child leukemia, brain cancer in adults and children, female and male breast cancer, spontaneous abortions, suicide, Alzheimer disease, amiotrophic lateral sclerosis and cardiovascular diseases including myocardial infarction. Various diseases are related to the different origin of the radiation, and the biological mechanisms involved in disease generation are analyzed. Research performed in the USSR and afterwards in Russia on health effects of mobile telephony are summarized, these investigations originated the regulation in this country and afterwards in West Europe, and influenced the decisions of WHO on its carcinogenicity...

Una aproximación al cáncer mediante el ajuste de distribucionesubpoblacionales afectadas por campos electromagnéticos / An approach to cancer through adjustment of subpopulational distributions affected by electromagnetic fields

El uso de los campos electromagnéticos (CEM) se encuentra bastante generalizado. La influencia que pudieran ejercer a nivel biológico no es del todo conocida. El objetivo del estudio es la aproximación de la distribución de la posible modificación estructural o funcional biológica debida a una exposición a CEM de frecuencias extremadamente bajas (FEB). Se trata de un estudio inferencial descriptivo de la exposición y distribución de linfocitos T a CEM de FEB con un comparativo entre la investigación descriptiva-investigación explicativa y aporte de metodología bayesiana. Se presenta una sensible variabilidad en los efectos biológicos por exposición a CEM, por lo que las distribuciones y comportamientos pueden verse afectados entre experimentos, atendiendo al desarrollo de los mismos y al carácter de la variable de posible influencia en la exposición. El empleo del análisis bayesiano frente a las técnicas frecuentistas aporta evidencias entre las diferentes proporciones, resultando más informativo que losmétodos convencionales.

The use of electromagnetic fields is fairly widespread. At biological level, the influence they could exert is not fully understood. The study's objective is to approximate the distribution of possible structural or functional biological changes due to the exposure to extremely low frequency electromagnetic fields. It’s a descriptive inferential study of the exposure and distribution of T lymphocytes to extremely low frequency electromagnetic fields, and a comparison between the descriptive and explanatory research with the contribution of Bayesian methodology. It presents a significant variability in the biological effects of electromagnetic fields exposure, so that distributions and behavior may be affected between experiments in response to their development and character of the variable in relation to a possible influence of exposure. The use of Bayesian analysis versus frequentist techniques provides evidences between the different proportions, resulting in more informative than conventional methods.

Radio frequency electromagnetic radiation (RF-EMR) from GSM (0.9/1.8GHz) mobile phones induces oxidative stress and reduces sperm motility in rats

INTRODUCTION: Mobile phones have become indispensable in the daily lives of men and women around the globe. As cell phone use has become more widespread, concerns have mounted regarding the potentially harmful effects of RF-EMR from these devices. OBJECTIVE: The present study was designed to evaluate the effects of RF-EMR from mobile phones on free radical metabolism and sperm quality. MATERIALS AND METHODS: Male albino Wistar rats (10-12 weeks old) were exposed to RF-EMR from an active GSM (0.9/1.8 GHz) mobile phone for 1 hour continuously per day for 28 days. Controls were exposed to a mobile phone without a battery for the same period. The phone was kept in a cage with a wooden bottom in order to address concerns that the effects of exposure to the phone could be due to heat emitted by the phone rather than to RF-EMR alone. Animals were sacrificed 24 hours after the last exposure and tissues of interest were harvested. RESULTS: One hour of exposure to the phone did not significantly change facial temperature in either group of rats. No significant difference was observed in total sperm count between controls and RF-EMR exposed groups. However, rats exposed to RF-EMR exhibited a significantly reduced percentage of motile sperm. Moreover, RF-EMR exposure resulted in a significant increase in lipid peroxidation and low GSH content in the testis and epididymis. CONCLUSION: Given the results of the present study, we speculate that RF-EMR from mobile phones negatively affects semen quality and may impair male fertility.

Cell phones and tumor: still in no man's land.

The use of cell phones is increasing worldwide at a phenomenal pace. While cellular communication has dramatically influenced our lifestyle, its impact on human health has not been completely assessed. Widespread concern continues in the community about the deleterious effects of radiofrequency radiations (with which cell phones operate) on human tissues and the subsequent potential for carcinogenesis. A detailed survey of published studies researching this question was done in preparation of this manuscript. Included in the survey were case reports, in vitro studies, population based retrospective studies and other investigations. The database of indexed journals was searched for key words like 'cell phone', 'radiation', 'cancer' and 'radio waves'. Guidelines issued by the World Health Organization, federal and technical authorities, Institute of Electrical and Electronic Engineers and the International Commission for Non-Ionizing Radiation Protection were reviewed. The evaluation of current evidence provided by various studies to suggest the possible carcinogenic potential of radiofrequency radiation is inconclusive. This risk assumes significance in light of the burgeoning number of people who are continually exposed to the high frequency radiation from cell phones and towers that serve as receiving and transmitting stations. The aim of this review is to identify limitations in past studies, present available data for consideration, and identify gaps in the current knowledge base. This will provide impetus and direction for further research and allow informed decisions pertaining to cell phone use to be made.

An epidemiological review of mobile telephones and cancer.

Mobile telecommunication technology became commercially available about 20-25 years ago in different countries around the world. The industry has grown exponentially over the years and, currently, the number of mobile phone users is estimated to be over 3.8 billion, more than half the world's population. Thus, because of such a large population-at-risk, any health hazard from these devices promises to have a large epidemiological impact. Intense speculation and investigation into the relationship between mobile phone usage and cancer has led to the publication of numerous, often contradictory, reports on this subject. This review aims to provide a large body of reported evidence to help medical professionals disseminate evidence-based information to their patients.

Health hazards of mobile phones: an Indian perspective.

The mobile phone industry has been one of the fastest growing industries in modern history. Today, India has million mobile phone users, and mobile phones account for 88% of all telecommunication users. The rural sector accounts for more than 25% of all wireless phone users and this proportion is bound to grow as affordability of mobile phones continues to increase. In the years ahead, an ever-increasing number exposed for long periods of time to radiation from mobile phones. In 2008, the Telecom Commission (the policy-making body of the Department of Telecommunicatics, Government of India) adopted the emission guidelines prescribed by the International Commission on Non-Protection (ICNIRP). Studies have demonstrated that usage behaviours, such as duration of usage and predominant, one-sided use of mobile phones are some of the chief risks that increase likelihood of hazards resulting from mobile phone use. This article attempts to present the basic biophysics of these devices and explain the health hazards of electromagnetic radiation exposure in terms of thermal and non-thermal effects. We also present some preventive measures that can reduce the risk of these hazards.

Harmful effects of 41 and 202 MHz radiations on some body parts and tissues.

Many types of invisible electromagnetic waves are produced in our atmosphere. When these radiations penetrate our body, electric fields are induced inside the body, resulting in the absorption of power, which is different for different body parts and also depends on the frequency of radiations. Higher power absorption may result into health problems. In this communication, effects of electromagnetic waves (EMW) of 41 and 202 MHz frequencies transmitted by the TV tower have been studied on skin, muscles, bone and fat of human. Using international standards for safe exposure limits of specific absorption rate (SAR), we have found the safe distance from TV transmission towers for two frequencies. It is suggested that transmission towers should be located away from the thickly populated areas and people should keep away from the transmission towers, as they radiate electromagnetic radiations that are harmful to some parts/tissues of body.

Local exposure of 849 MHz and 1763 MHz radiofrequency radiation to mouse heads does not induce cell death or cell proliferation in brain

Even though there is no direct evidence to prove the cellular and molecular changes induced by radiofrequency (RF) radiation itself, we cannot completely exclude the possibility of any biological effect of mobile phone frequency radiation. We established a carousel-type exposure chamber for 849 MHz or 1763 MHz of mobile phone RF radiation to expose RF to the heads of C57BL mice. In this chamber, animals were irradiated intermittently at 7.8 W/kg for a maximum of 12 months. During this period, the body weights of 3 groups-sham, 849 MHz RF, and 1763 MHz RF-did not show any differences between groups. The brain tissues were obtained from 3 groups at 6 months and 12 months to examine the differences in histology and cell proliferation between control and RF exposure groups, but we could not find any change upon RF radiation. Likewise, we could not find changes in the expression and distribution of NeuN and GFAP in hippocampus and cerebellum, or in cell death by TUNEL assay in RF exposure groups. From these data, we conclude that the chronic exposure to 849 MHz and 1763 MHz RF radiation at a 7.8 W/kg specific absorption rate (SAR) could not induce cellular alterations such as proliferation, death, and reactive gliosis.

Biomarkers of induced electromagnetic field and cancer.

The present article delineates the epidemiological and experimental studies of electromagnetic field which affects various tissues of human body. These affects lead to cell proliferation, which may lead to cancer formation. Certain biomarkers have been identified which are one way or the other responsible for tumor promotion or co-promotion. These are (i) melatonin, a hormone secreted by pineal gland, (ii) Ca2+, which is essential in the regulation of the resting membrane potential and in the sequence of events in synaptic excitation and neurotransmitter, release are affected by electromagnetic field, (iii) ornithine decarboxylase (ODC), a rate-limiting enzyme in the biosynthesis of polyamines, considered as a useful biological marker; over expression of ODC can cause cell transformation and enhancement of tumor promotion. (iv) protein kinase is an enzyme, which transfers phosphate groups from ATP to hydroxyl groups in the amino acid chains of acceptor proteins, and (v) Na+-K+ ATPase, which transports sodium and potassium ions across the membrane has a critical role in living cells. The various possible mechanisms depending upon non equilibrium thermodynamics, co-operativism, stochastic and resonance are discussed as possible models of signal transduction in cytosol, thereby controlling the transcription phenomena. Finally a mechanism comprising the extremely low frequency and radio frequency (RF)/microwave (MW) modulated field is compared.

Efecto del personal estéreo en la audición para las altas frecuencias / Effect of a personal stereo on high frequencies hearing

Con el fin de conocer los hábitos de uso del personal estéreo y determinar si afecta la audición de las altas frecuencias, provocando un descenso de los umbrales auditivos, cuya magnitud estaría en directa relación aplicación de una encuesta a un grupo de 72 jóvenes universitarios, de los cuales se obtuvo con el tiempo de utilización de tales aparatos, se realizó un estudio que consistió en la una muestra de 22 sujetos de ambos sexos, otológicamente normales, cuyas edades fluctuaron entre los 21 y 27 años. Ellos participaron voluntariamente en la evaluación experimental del uso del personal estéreo, consistente en la realización de una audiometría entre 125 a 16.000 Hz, antes y después de utilizar el personal estéreo a niveles que fluctuaron entre los 60 dB(A) y 84 dB(A), durante 30 minutos en una primera sesión, y 60 minutos en la segunda, con un intervalo mínimo de 24 horas entre ambas. Los resultados confirman la popularidad del personal estéreo entre los jóvenes encuestados, siendo además utilizado frecuentemente en ambientes con altos niveles de ruido y sugieren que el uso del personal estéreo, bajo las condiciones planteadas en este estudio, produce un descenso significativo de los umbrales auditivos a nivel de las altas frecuencias (9.000 a 16.000 Hz) y de las frecuencias evaluadas en audiometría convencional (125 a 8.000 Hz), sin evidenciarse la influencia del tiempo de utilización de tales aparatos. El análisis estadístico de los datos se efectuó mediante la prueba t de Student para muestras pareadas con un nivel de significación de un 5 por ciento.

Medición de la intensidad de campo eléctrico de los equipos de onda corta / Measurement of the electric field intensity of short wave equipments

El presente estudio descriptivo transversal tiene por objetivo determinar el cumplimiento de las recomendaciones de emisión de ondas electromagnéticas en equipos de onda corta (27,12 MHz) terapéutica de los servicios de salud pública de la región metropolitana durante el año 2003. Luego de la medición y registro de la intensidad de campo eléctrico (V/Mt) en el campo cercano (1 metro del foco) en la población de equipos de onda corta en funcionamiento, los resultados obtenidos indicaron que en el total de equipos de la Región Metropolitana (N = 47), el 97,87 por ciento (n = 46) cumple con la recomendación internacional de la ICNIRP (International on Non-ionizing Radiation Protection) a nivel ocupacional (61 V/Mt) de intensidad de campo eléctrico (Nivel de Confianza 95 por ciento).

Efecto de ondas ultrasónicas de 25 a 50 Khz sobre el rendimiento reproductivo y el peso corporal de ratas Wistar / Effect of 22-50 KHz ultrasonic waves on reproductive performance and weight gain in Wistar rats

El presente trabajo se realizó con el propósito de conocer el efecto de las ondas ultrasónicas generadas por un dispositivo diseñado para ahuyentar roedores y disminuir su reproducción. El efecto de este equipo fue estudiado en ratas Wistar mantenidas en condiciones de bioterio. Con ese propósito se formaron dos grupos de ratas Wistar, uno testigo y el otro experimental, en donde se determinó si la acción constante de un dispositivo productor de ondas ultrasónicas, durante 12 semanas, interfiere con la capacidad reproductiva de ratas Wistar, evaluada por el número de días a parto, número de crías nacidas y destetadas. También se determinó la influencia de las ondas ultrasónicas en el crecimiento y desarrollo de las crías, utilizando como indicador la ganancia de peso semanal desde el destete hasta la doceava semana experimental. Los resultados obtenidos indican que las ondas ultrasónicas no afectan el peso corporal, ya que mediante la prueba de mediciones repetidas se comprobó que si bien existe diferencia aritmética, no hay diferencia estadística entre ambos grupos (P>0.05). En lo que respecta a las crías, el grupo tratado obtuvo 20 crías más que el grupo testigo; sin embargo, no existe diferencia estadística entre ambos grupos (P>0.05). La presencia continua de ondas ultrasónicas tampoco interfirió con la ganancia de peso de las crías, en comparación con el grupo testigo (P>0.05). Se concluye que las ondas ultrasónicas generadas por el aparato no afectan el tamaño y curva de crecimiento posterior al destete de la camada. Como consecuencia de lo anterior no parece recomendable utilizar este tipo de aparatos como un método para el control de roedores.