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PubMedDate not supplied

Household electromagnetic fields and breast cancer in elderly women.

The relationship between the rate of household low-frequency electromagnetic fields (EMF) and incidences of mammary tumors was studied in 1290 clinical case-records of female patients aged 60 and more over a period of 26 years, based on the materials of the Edith Wolfson Medical Center, Israel. The studied material was divided into two groups, each corresponding to a period of 13 years. Group I included patients with mammary tumors under observation from 1978 to 1990, who rarely used EMF-generating appliances. Group II consisted of patients being under observation in the period between 1991 and 2003, characterized by much more extensive use of personal computers (more than 3 hours a day), mobile telephones, television sets, air conditioners and other household electrical appliances generating EMF. 200,527 biopsy and surgery samples were analyzed. Mammary tumors were found in 2824 women (1.4%), of which 1290 cases (45.6%) were observed in elderly women. Most of the observed tumors--1254 (97.2%)--were epithelial neoplasms. Mammary tumors were found in 585 elderly women in Group I and 705 women in Group II. The case records of these patients showed that 114 elderly women (19.5%) in Group I and 360 (51.1%) in Group II were regularly exposed to EMF (mostly from personal computers) for at least 3 hours a day (chi2=57.2, p<0.001). There was a statistically significant influence of EMF on the formation of all observed epithelial mammary tumors in Group II. This influence is most evident for invasive ductal carcinomas, which was the commonest form of cancer in elderly women.

Age Distribution↗
PubMed2002

The excretion of 6-hydroxymelatonin sulfate in healthy young men exposed to electromagnetic fields emitted by cellular phone -- an experimental study.

OBJECTIVES: It is quite likely that non-visible electromagnetic fields (EMF) may affect melatonin production. Some studies confirmed this hypothesis and showed that extremely low EMF altered pineal function in animals and humans. Thus, it is reasonable to suppose that EMF emitted by cellular phones may also influence secretion of melatonin. The present study sought to evaluate possible effect of the exposure to EMF emitted by cellular phone on 6-hydroxymelatonin sulfate (6-OHMS) excretion, which reflects melatonin levels in blood. MATERIAL AND METHODS: The examined group consisted of 9 healthy males aged 19-29 years. The experiment was performed under controlled conditions (the light intensity-50 lx till midnight and 0 lx during night). Each person was examined twice: on a day without exposure (control day, C-day) and on a day with continuous exposure (60 min. exposure from cellular phone, frequency 900 MHz, pulsed with 217 Hz, pulse with 576 micros, SAR 1.23 W/kg, E-day). From 7 p.m. to 8 p.m. they used a cellular phone. The subjects did not know which day was E-day, and which was C-day. From 8 p.m. till midnight the subjects listened to music and than they slept till 7 a.m. next day. Urine samples were collected at 7 p.m., at midnight, and at 7 a.m. in the same way in C-day as in E-day. Sample were frozen for later ELISA analysis of 6-OHMS. The 6-OHMS ELISA kit from Immuno-Biological Laboratories (Hamburg) was used for measurement of 6-OHMS. The data were analysed using Wilcoxon matched-pairs signed-ranks test for each subject and for the whole group. We compared 6-OHMS level on the E-day and on the C-day separately for 3 time-points - 7 p.m., midnight, 7 a.m. RESULTS: Mean 6-OHMS level in both experiments did not differ significantly for any of the respective time points. Circadian variations of 6-OHMS level were detected in all subjects. CONCLUSIONS: The results of our investigation has demonstrated that EMF emitted by cellular phones has no distinct influence on the melatonin level.

Adult↗
PubMed1999

Myocardial protection conferred by electromagnetic fields.

BACKGROUND: It has been reported that electromagnetic (EM) fields induce stress proteins in vitro. These proteins have been shown to be important in recovery from ischemia/reperfusion. It was, therefore, hypothesized that EM fields could activate stress responses in vivo and protect myocardial tissue during anoxia. METHODS AND RESULTS: Chick embryos were exposed to 4-, 6-, 8-, and 10- microT and 60-Hz EM fields for 20 minutes followed by a 1-hour rest period before placement in an anoxic chamber. Embryos were reoxygenated when survival of controls dropped to <40%, and final observations were made 30 minutes later. Data from 80 experiments (>500 EM field-exposed embryos) indicated that EM field protection was extremely significant (P<0.0001). Survival rates were 39.6% in controls and 68.7% in field-exposed embryos. In a second set of experiments, embryos were exposed for 20 minutes to several pretreatments: (1) hyperthermia (43 degreesC), (2) 60-Hz, 8- microT EM fields, or (3) 60-Hz, 8- microT EM fields plus a random EM noise field (8 microT). Embryo survival was 37.7% (control), 57.6% (heated), 69% (60-Hz EM field only), and 41.5% (60-Hz EM field plus EM noise). To confirm that heating resulting from field exposures did not occur, thermocouples were placed into several eggs at the site of the embryo during exposure; no increase in temperature was noted. CONCLUSIONS: We conclude that athermal EM field exposures induce stress responses that protect chick embryo myocardium from anoxia damage. These results suggest that EM field exposures may be a useful, noninvasive means of minimizing myocardial damage during surgery, transplantation, or heart attack in humans.

Animals↗
PubMed2026

The Effect of Pulsed Electromagnetic Field on Pain and Foot Function Index in Patients With Plantar Fasciitis.

The plantar fascia is a thick band of connective tissue that originates from the heel, and its inflammation is the most common cause of heel pain in adults. The Pulsed Electromagnetic Field (PEMF) is a non-invasive modality in the field of physiotherapy. This study aimed to determine the effects of PEMF on pain scores and the Foot Function Index (FFI) in patients with plantar fasciitis (PF). In this clinical trial study, 40 patients with PF, aged between 20 and 68 years, were randomly assigned in a block design into two groups: the Conventional Physiotherapy (CP) group and the CP plus PEMF (CPP) group. The Numerical Pain Rating Scale (NPRS) and the FFI questionnaire were used to assess the pain score (morning and evening pain) and foot function, respectively. Assessments were conducted before the study, at the tenth session of the CP and CPP groups, and 4 weeks later. The study variables in both the CP and CPP groups changed significantly (p&#x2009;<&#x2009;0.05). In comparing the results between the two groups, the reduction in evening pain scores in the CPP group was significant compared to the CP group (p&#x2009;<&#x2009;0.05). In comparison, there was no significant difference in morning pain scores between the two groups. The FFI score in the CPP group significantly decreased compared to the CP group. Both CP and CPP are effective in reducing pain and the FFI in patients with PF. The addition of PEMF to CP demonstrates a more significant effect on reducing evening pain and somewhat on reducing the FFI in patients compared to CP alone. However, it did not have an additional effect on reducing morning pain. Bioelectromagnetics. 00:00-00, 2026. &#xa9; 2026 Bioelectromagnetics Society.

Humans↗
PubMed2006

Effects of extremely-low-frequency pulsed electromagnetic fields on collagen synthesis in rat skin.

To investigate the effects of extremely-low-frequency PEMFs (pulsed electromagnetic fields) on the synthesis of epidermal collagen, six groups of animals each consisting of eight mature male rats were selected randomly: one group for the control and five for the test. Using a parallel set of Helmholtz coils, a uniform field intensity of 2 mT at different frequencies of 25, 50 and 100 Hz yielded the most effective frequency to be 25 Hz. Then, at this frequency, two different field intensities of 1 and 4 mT were applied. The treatment time of 2.5 h/day lasted for 8 days, keeping the same procedure for the control group, except with the field turned off. On the ninth day, the rats were killed and skin samples from the dorsal region were taken for collagen assessment by measuring hydroxyproline content using the Stegemann-Stalder [(1967) Clin. Chim. Acta 8, 267-273] method. The results indicated that a PEMF of 2 mT at 25 Hz increased the collagen synthesis (P < 0.05). The other intensities and frequency setting did not have any noticeable effect; however, at a frequency of 25 Hz at 4 mT, collagen increase was also noticed. It was concluded that at 25 Hz under a field setting of 2 mT for the duration of 8 days, stimulation of skin at 2.5 h/day would cause increase in collagen synthesis in rat skin.

Animals↗
PubMed1979

Influence on vision of extremely low frequence electromagnetic fields. Industrial measurements, magnetophosphene studies volunteers and intraretinal studies in animals.

The strong electric currents used for heating purposes in welding and steel industries set up related magnetic fields (generally 0.1--10 mT and 50 Hz). Such fields 10--50 Hz, 0--40 mT) were used to induce visual light phenomena, magnetophosphenes. Threshold values for magnetophosphenes were determined as a function of magnetic field frequency as well as colour and intensity of the background illumination. A typical sensitivity maximum was found at 20--25 Hz. Differences between volunteers with normal colour vision and colour defective ones were observed. The frog retina was exposed to the same type of fields. Retinal activity, induced by the fields, was registered from the ganglion cell layer by means of microelectrode technique. The results indicate that magnetophosphenes are generated in the retina and in the same channels that are normally propagating signals induced by light of different qualities. The findings may be of guidance when formulating threshold limit values for extremely low frequency electromagnetic fields in industry.

Animals↗
PubMed2004

Human head exposure to a 37 Hz electromagnetic field: effects on blood pressure, somatosensory perception, and related parameters.

Previous studies have shown that exposure to an electromagnetic field (EMF) of 37 Hz at a flux density of 80 microT peak enhances nociceptive sensitivity in mice. Here we examined the effects on pain sensitivity and some indexes of cardiovascular regulation mechanisms in humans by measuring electrical cutaneous thresholds, arterial blood pressure, heart rate and its variability, and stress hormones. Pain and tolerance thresholds remained unchanged after sham exposure but significantly decreased after electromagnetic exposure. Systolic blood pressure was significantly higher during electromagnetic exposure and heart rate significantly decreased, both during sham and electromagnetic exposure, while the high frequency (150-400 mHz) component of heart rate variability, which is an index of parasympathetic activity, increased as expected during sham exposure but remained unchanged during electromagnetic exposure. Cortisol significantly decreased during sham exposure only. These results show that exposure to an EMF of 37 Hz also alters pain sensitivity in humans and suggest that these effects may be associated with abnormalities in cardiovascular regulation.

Adult↗
PubMed1997

Therapeutic effects of alternating current pulsed electromagnetic fields in multiple sclerosis.

Multiple sclerosis is the third most common cause of severe disability in patients between the ages of 15 and 50 years. The cause of the disease and its pathogenesis remain unknown. The last 20 years have seen only meager advances in the development of effective treatments for the disease. No specific treatment modality can cure the disease or alter its long-term course and eventual outcome. Moreover, there are no agents or treatments that will restore premorbid neuronal function. A host of biological phenomena associated with the disease involving interactions among genetic, environmental, immunologic, and hormonal factors, cannot be explained on the basis of demyelination alone and therefore require refocusing attention on alternative explanations, one of which implicates the pineal gland as pivotal. The pineal gland functions as a magnetoreceptor organ. This biological property of the gland provided the impetus for the development of a novel and highly effective therapeutic modality, which involves transcranial applications of alternating current (AC) pulsed electromagnetic fields in the picotesla flux density. This review summarizes recent clinical work on the effects of transcranially applied pulsed electromagnetic fields for the symptomatic treatment of the disease.

Adult↗
PubMed2004

Effect of 50 Hz electromagnetic fields on the induction of heat-shock protein gene expression in human leukocytes.

Although evidence is controversial, exposure to environmental power-frequency magnetic fields is of public concern. Cells respond to some abnormal physiological conditions by producing cytoprotective heat-shock (or stress) proteins. In this study, we determined whether exposure to power-frequency magnetic fields in the range 0-100 microT rms either alone or concomitant with mild heating induced heat-shock protein gene expression in human leukocytes, and we compared this response to that induced by heat alone. Samples of human peripheral blood were simultaneously exposed to a range of magnetic-field amplitudes using a regimen that was designed to allow field effects to be distinguished from possible artifacts due to the position of the samples in the exposure system. Power-frequency magnetic-field exposure for 4 h at 37 degrees C had no detectable effect on expression of the genes encoding HSP27, HSP70A or HSP70B, as determined using reverse transcriptase-PCR, whereas 2 h at 42 degrees C elicited 10-, 5- and 12-fold increases, respectively, in the expression of these genes. Gene expression in cells exposed to power-frequency magnetic fields at 40 degrees C was not increased compared to cells incubated at 40 degrees C without field exposure. These findings and the extant literature suggest that power-frequency electromagnetic fields are not a universal stressor, in contrast to physical agents such as heat.

Adult↗