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1.
J Radiat Res ; 58(1): 48-58, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27694283

RESUMO

In everyday life, people are exposed to radiofrequency (RF) electromagnetic fields (EMFs) with multiple frequencies. To evaluate the possible adverse effects of multifrequency RF EMFs, we performed an experiment in which pregnant rats and their delivered offspring were simultaneously exposed to eight different communication signal EMFs (two of 800 MHz band, two of 2 GHz band, one of 2.4 GHz band, two of 2.5 GHz band and one of 5.2 GHz band). Thirty six pregnant Sprague-Dawley (SD) 10-week-old rats were divided into three groups of 12 rats: one control (sham exposure) group and two experimental (low- and high-level RF EMF exposure) groups. The whole body of the mother rats was exposed to the RF EMFs for 20 h per day from Gestational Day 7 to weaning, and F1 offspring rats (46-48 F1 pups per group) were then exposed up to 6 weeks of age also for 20 h per day. The parameters evaluated included the growth, gestational condition and organ weights of the dams; the survival rates, development, growth, physical and functional development, memory function, and reproductive ability of the F1 offspring; and the embryotoxicity and teratogenicity in the F2 rats. No abnormal findings were observed in the dams or F1 offspring exposed to the RF EMFs or to the F2 offspring for any of the parameters evaluated. Thus, under the conditions of the present experiment, simultaneous whole-body exposure to eight different communication signal EMFs at frequencies between 800 MHz and 5.2 GHz did not show any adverse effects on pregnancy or on the development of rats.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Feto/efeitos da radiação , Ondas de Rádio/efeitos adversos , Desmame , Irradiação Corporal Total , Animais , Comportamento Animal/efeitos da radiação , Cruzamentos Genéticos , Feminino , Fertilidade/efeitos da radiação , Aprendizagem em Labirinto/efeitos da radiação , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos Sprague-Dawley , Reprodução/efeitos da radiação
2.
Bioelectromagnetics ; 35(7): 497-511, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25196377

RESUMO

The present experimental study was carried out with rats to evaluate the effects of whole body exposure to 2.14 GHz band code division multiple access (W-CDMA) signals for 20 h a day, over three generations. The average specific absorption rate (SAR, in unit of W/kg) for dams was designed at three levels: high (<0.24 W/kg), low (<0.08 W/kg), and 0 (sham exposure). Pregnant mothers (4 rats/group) were exposed from gestational day (GD) 7 to weaning and then their offspring (F1 generation, 4 males and 4 females/dam, respectively) were continuously exposed until 6 weeks of age. The F1 females were mated with F1 males at 11 weeks old, and then starting from GD 7, they were exposed continuously to the electromagnetic field (EMF; one half of the F1 offspring was used for mating, that is, two of each sex per dam and 8 males and 8 females/group, except for all offspring for the functional development tests). This protocol was repeated in the same manner on pregnant F2 females and F3 pups; the latter were killed at 10 weeks of age. No abnormalities were observed in the mother rats (F0 , F1 , and F2 ) and in the offspring (F1 , F2 , and F3 ) in any biological parameters, including neurobehavioral function. Thus, it was concluded that under the experimental conditions applied, multigenerational whole body exposure to 2.14 GHz W-CDMA signals for 20 h/day did not cause any adverse effects on the F1 , F2 , and F3 offspring.


Assuntos
Encéfalo/efeitos da radiação , Telefone Celular , Campos Eletromagnéticos , Animais , Peso Corporal/efeitos da radiação , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Comportamento Exploratório/efeitos da radiação , Feminino , Masculino , Exposição Materna , Aprendizagem em Labirinto/efeitos da radiação , Atividade Motora/efeitos da radiação , Tamanho do Órgão , Exposição Paterna , Radiogenética , Radiometria , Ratos Sprague-Dawley , Reprodução/efeitos da radiação
3.
Bioelectromagnetics ; 34(8): 589-98, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24037832

RESUMO

In this study, we investigated subjective and objective effects of mobile phones using a Wideband Code Division Multiple Access (W-CDMA)-like system on human sleep. Subjects were 19 volunteers. Real or sham electromagnetic field (EMF) exposures for 3 h were performed before their usual sleep time on 3 consecutive days. They were exposed to real EMF on the second or third experimental day in a double-blind design. Sleepiness and sleep insufficiency were evaluated the next morning. Polysomnograms were recorded for analyses of the sleep variables and power spectra of electroencephalograms (EEG). No significant differences were observed between the two conditions in subjective feelings. Sleep parameters including sleep stage percentages and EEG power spectra did not differ significantly between real and sham exposures. We conclude that continuous wave EMF exposure for 3 h from a W-CDMA-like system has no detectable effects on human sleep.


Assuntos
Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Sono/efeitos da radiação , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Polissonografia , Autorrelato , Sono/fisiologia , Adulto Jovem
4.
Radiat Res ; 173(3): 362-72, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20199221

RESUMO

Abstract The recent steep increase in the number of users of cellular phones is resulting in marked increase of exposure of humans to radiofrequency electromagnetic fields (EMFs). Children are of particular concern. Our goal was to evaluate potential adverse effects of long-term whole-body exposure to EMFs simulating those from base stations for cellular phone communication. Pregnant rats were given low, high or no exposure. At the high level, the average specific absorption rate (SAR)for the dams was 0.066-0.093 W/kg. The SAR for the fetuses and the F(1) progeny was 0.068-0.146 W/kg. At the low level, the SARs were about 43% of these. The 2.14 GHz signals were applied for 20 h per day during the gestation and lactation periods. No abnormal findings were observed in either the dams or the F(1) generation exposed to the EMF or in the F(2) offspring. Parameters evaluated included growth, gestational condition and organ weights for dams and survival rates, development, growth, physical and functional development, hormonal status, memory function and reproductive ability of the F(1) offspring (at 10 weeks of age) along with embryotoxicity and teratogenicity in the F(2) rats. Thus, under our experimental conditions, whole-body exposure to 2.14 GHz for 20 h per day during gestation and lactation did not cause any adverse effects on pregnancy or the development of rats.


Assuntos
Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Feto/efeitos da radiação , Ondas de Rádio/efeitos adversos , Animais , Feminino , Feto/fisiologia , Humanos , Lactação/efeitos da radiação , Masculino , Aprendizagem em Labirinto/fisiologia , Aprendizagem em Labirinto/efeitos da radiação , Gravidez , Doses de Radiação , Ratos , Reprodução/fisiologia , Reprodução/efeitos da radiação , Fatores de Tempo
5.
Bioelectromagnetics ; 30(3): 205-12, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19194858

RESUMO

The present study was designed to evaluate whether gestational exposure to an EMF targeting the head region, similar to that from cellular phones, might affect embryogenesis in rats. A 1.95-GHz wide-band code division multiple access (W-CDMA) signal, which is one applied for the International Mobile Telecommunication 2000 (IMT-2000) system and used for the freedom of mobile multimedia access (FOMA), was employed for exposure to the heads of four groups of pregnant CD(SD) IGS rats (20 per group) for gestational days 7-17. The exposure was performed for 90 min/day in the morning. The spatial average specific absorption rate (SAR) for individual brains was designed to be 0.67 and 2.0 W/kg with peak brain SARs of 3.1 and 7.0 W/kg for low (group 3) and high (group 4) exposures, respectively, and a whole-body average SAR less than 0.4 W/kg so as not to cause thermal effects due to temperature elevation. Control and sham exposure groups were also included. At gestational day 20, all dams were killed and fetuses were taken out by cesarean section. There were no differences in maternal body weight gain. No adverse effects of EMF exposure were observed on any reproductive and embryotoxic parameters such as number of live (243-271 fetuses), dead or resorbed embryos, placental weights, sex ratios, weights or external, visceral or skeletal abnormalities of live fetuses.


Assuntos
Encéfalo/efeitos da radiação , Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Embrião de Mamíferos/efeitos da radiação , Exposição Materna , Animais , Anormalidades Congênitas/etiologia , Exposição Ambiental , Feminino , Gravidez , Prenhez/efeitos da radiação , Ratos , Ratos Sprague-Dawley
6.
Bioelectromagnetics ; 28(7): 562-72, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17516507

RESUMO

The present study was performed to evaluate effects of a 2-year exposure to an electromagnetic near-field (EMF) equivalent to that generated by cellular phones on tumor development in the central nervous system (CNS) of rats. For this purpose, pregnant F344 rats were given a single administration of N-ethylnitrosourea (ENU) on gestational day 18. A total of 500 pups were divided into five groups, each composed of 50 males and 50 females: Group 1, untreated controls; Group 2, ENU alone; Groups 3 to 5, ENU + EMF (sham exposure and two exposure levels). A 1.95-GHz wide-band code division multiple access (W-CDMA) signal, which is a feature of the International Mobile Telecommunication 2000 (IMT-2000) cellular system was employed for exposure of the rat head starting from 5 weeks of age, 90 min a day, 5 days a week, for 104 weeks. Brain average specific absorption rates (SARs) were designed to be .67 and 2.0 W/kg for low and high exposures, respectively. The incidence and numbers of brain tumors in female rats exposed to 1.95-GHz W-CDMA signals showed tendencies to increase but without statistical significance. Overall, no significant increase in incidences or numbers, either in the males or females, was detected in the EMF-exposed groups. In addition, no clear changes in tumor types in the brain were evident. Thus, under the present experimental conditions, exposure of heads of rats to 1.95-GHz W-CDMA signals for IMT-2000 for a 2-year period was not demonstrated to accelerate or otherwise affect ENU-initiated brain tumorigenesis.


Assuntos
Neoplasias Encefálicas/etiologia , Neoplasias Encefálicas/patologia , Telefone Celular , Campos Eletromagnéticos , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/patologia , Animais , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Exposição Ambiental , Etilnitrosoureia , Feminino , Masculino , Doses de Radiação , Ratos , Ratos Endogâmicos F344
7.
Bioelectromagnetics ; 26(1): 59-68, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15605402

RESUMO

The present study was designed to evaluate whether a 2 year exposure to an electromagnetic field (EMF) equivalent to that generated by cellular phones can accelerate tumor development in the central nervous system (CNS) of rats. Brain tumorigenesis was initiated by an intrauterine exposure to N-ethylnitrosourea (ENU) on gestational day 18. A total of 500 pups were divided into five groups, each composed of 50 males and 50 females: Group 1, untreated control; Group 2, ENU alone; Groups 3-5, ENU + EMF (sham exposure and 2 exposure levels). A 1.439 GHz time division multiple access (TDMA) signal for the Personal Digital Cellular (PDC), Japanese standard cellular system was used for the exposure of the rat head starting from 5 weeks of age, 90 min a day, 5 days a week, for 104 weeks. Brain average specific absorption rate (SAR) was 0.67 and 2.0 W/kg for low and high exposures, respectively: whole body average SAR was less than 0.4 W/kg. There were no inter-group differences in body weights, food consumption, and survival rates. No increase in the incidences or numbers per group of brain and/or spinal cord tumors, either in the males or females, was detected in the EMF exposed groups. In addition, no clear changes in tumor types were evident. Thus, under the present experimental conditions, 1.439 GHz EMF exposure to the heads of rats for a 2 year period was not demonstrated to accelerate or affect ENU initiated brain tumorigenesis.


Assuntos
Telefone Celular , Neoplasias do Sistema Nervoso Central/etiologia , Exposição Ambiental/efeitos adversos , Micro-Ondas/efeitos adversos , Neoplasias Induzidas por Radiação/etiologia , Medição de Risco/métodos , Neoplasias do Sistema Nervoso Central/patologia , Relação Dose-Resposta à Radiação , Incidência , Neoplasias Induzidas por Radiação/patologia , Doses de Radiação , Fatores de Risco , Fatores Sexuais , Análise de Sobrevida
8.
Bioelectromagnetics ; 25(3): 228-33, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15042632

RESUMO

To investigate the effect of systemic anesthesia on ocular effects and temperature in rabbit eyes exposed to microwaves, one eye each of 43 male pigmented rabbits (Dutch, 1.8-2.2 kg) was exposed at 2.45 GHz for 60-20 min (300 mW/cm2; 108 W/kg), either under anesthesia (ketamine hydrochloride (5 mg/kg) + xylazine (0.23 mg/kg)) or without anesthesia. Changes in the anterior segment were evaluated by image analysis utilizing a Scheimpflug camera, specular microscopy, and a laser flare cell meter. Temperatures within the eye were measured during microwave exposure by a Fluoroptic thermometer. The exposed eyes showed miosis, conjunctival congestion, corneal edema, and an increase in the light scattering of the anterior shallow cortex in the pupillary area of the lens. The group under systemic anesthesia showed much stronger symptoms than those treated without anesthesia. All of the anterior ocular changes disappeared within a week. The highest temperature during exposure was in the vitreous, followed by the anterior chamber, and the retrobulbar cavity of the orbit. The ocular temperatures of the rabbits under systemic anesthesia were 2-9 degrees C higher than those without anesthesia. Body temperature showed an increase of 1 degrees C during the exposure. Acute high intensity microwave exposure temporarily induced anterior segments inflammation and lens changes. The more pronounced ocular effects in the anesthetized rabbits were associated with the significantly higher ocular temperatures in the anesthetized animals. The influence of systemic anesthesia on ocular changes should be considered.


Assuntos
Anestésicos/farmacologia , Olho/efeitos dos fármacos , Olho/efeitos da radiação , Animais , Masculino , Micro-Ondas , Coelhos , Temperatura
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