BACKGROUND: So many electronic devices have been introduced in the operating room. However, little was known about the hazards of electromagnetic fields (EMF) to the human body. We have studied about how much the anesthesiologists are exposed to EMF. METHODS: In 19 operating rooms of our hospital, the intensity of magnetic fields was measured by an ELF (Extremely low frequency) field strength measurement system. The distances were 30 cm, 50 cm and the anesthesiologist's proximity to the monitoring devices. RESULTS: The average strength of 19 operating rooms were 2.22 +/- 1.13 mG at 30 cm from the monitors, 1.29 +/- 0.84 mG at 50 cm and 1.00 +/- 0.78 mG at the anesthesiologist's stand. CONCLUSIONS: We found that in some of our operating rooms the exposure to EMF was measured above Sweden's TCO limit which has been accepted as the EMF radiation rule for computer monitors. Although the hazards of EMF have not been definitely confirmed yet, the effort not to be exposed to EMF should be considered by anesthesiologists.
Electromagnetic Fields* ; Human Body ; Magnetic Fields ; Magnets* ; Operating Rooms*

Electromagnetic Fields ; Magnetic Fields ; Microwaves ; adverse effects ; Television

The purpose of this study was to evaluate the effects of magnetic field on cellular activity of MC3T3-El cells. The celular activity was monitored by alkaline phosphatase and DNA synthetic activity in control, static magnetic field and pulsed electromagnetic field groups. A static magnetic field was applied to the cell by placing one, two, three, four, and five samarium-cobalt magnets above and below each cell plate for 24hours per day. A pulsed electromagnetic field with a frequency of 100 herz was applied for 10 hours per day. After 10 days of magnetic field exposure, there were increase of alkaline phosphatase activity in static magnetic field groups consisted of one, two and three magnetic groups, Alkaline phosphatase activities were not significantly increased in four and five magnetic groups, Application of pulsed electromagnetic field did not result in significant increase in alkaline phosphatase activity compared to control. DNA synthetic activity in both static and pulsed electromagnetic field group were not significantly different from that in control group, The result of this study suggest that magnetic field could have effect on the metabolism of bone cells related to the cellular metabolic process,
Alkaline Phosphatase* ; DNA* ; Electromagnetic Fields* ; Magnetic Fields* ; Magnets* ; Metabolism

This paper realized an electromagnetic tracking system based on electrically-controlled rotating magnetic field. A tracking system using the digital signal processor (DSP) as the control processing device was developed, including a controllable constant current source module, a magnetic field source module, a three-axis magnetic sensor and ADC interface circuit. The experimental results verified that each time the system could be stable positioning, average error of position was 0.282 cm, the average error of orientation was 0.696o, the positioning time was 1.572 s. Through calibration and further improvement of the hardware circuit, the performance of the system is expected to further improve.
Calibration ; Electromagnetic Phenomena ; Equipment Design ; Magnetic Fields

OBJECTIVETo investigate the effects of the static magnetic field (SMF) generated by dental magnetic attachments on osteoblastic proliferations, cell cycle distribution, and apoptosis ratio.

METHODSBy simulating those of the closed-field, the closure process and the open-field Magnedisc 800 magnetic attachments respectively, the in vitro cultured rat osteoblasts were exposed continuously to 12.5, 125, 250 mT SMF. The effects of the SMF on the proliferation of the cells were examined. MTT colorimetry test was performed to detect the effect of the SMF on the vitalities of cells. Flow cytometry was utilized to analyze the cell cycles and cell apoptosis rates.

RESULTSThe SMF exposure didn't change the vital osteoblasts number, the cell cycle distribution and proliferation activities of osteoblasts. The cell apoptosis situation were not observed statistical differences.

CONCLUSIONNo matter the closed-field, the closure process and the open-field magnetic attachments respectively, continuous simulating SMF-stimulation of magnetic attachments couldn't change osteoblasts proliferation activity, cell cycle distribution, and apoptosis ratio.

Animals ; Apoptosis ; Cell Cycle ; Cell Proliferation ; Electromagnetic Fields ; Magnetic Fields ; Magnetic Phenomena ; Magnetics ; Osteoblasts ; Rats

In this work we have measured the dose distribution and the percent depth dose of 20 MeV electron beam using the X-OMAT films in order to verify the effects of transverse magnetic field on high energy elecrtron beam in a phantom. The result shows about 30% increase of the percent depth dose at 4.5 cm depth under the transverse magnetic field of 1.5 Tesla at 7.5 cm depth. We have verified that these were in an agreement with other theoretical results.
Magnetic Fields*

Pulsed electromagnetic field (PEMF) was used first to induce osteogenesis in 1974. The appliance which was consisted of the Helmholtz coil configuration have used to osteogensis. The objective of this study was to determine whether PEMF, a frequency of 100 Hz and magnetic field strength of 38 gauss applied to the calvarial defect in rabbit, could affect the induction of osteogenesis and the healing of the graft bone. This field should not produce excitation of nerve or muscle and heating the tissue. To evaluate the effect of PEMF on osteogenesis, 16 rabbit under the same condition was divided into 8 experimental groups and 8 control groups. 10 mm calvarial bone defects were formed around sagittal suture. The defect of left side was left without graft while the defect of right side was grafted by bone harvested from left side. A pulsed electromagnetic field was applied for 8 hours per day. Each group was sacrificed after 1 week, 2 weeks, 4 weeks, 8 weeks. Microscopic specimens were obtained from the calvarial bone defects and surrounding tissue using Hematoxylin-Eosin staining method. The results were as follows. 1. In the group which pulsed electromagnetic field was applied, new bone formation filled up the defect was observed after 4 and 8 weeks effectively. 2. There are no difference in the healing period for the fusion between the bone and graft bone. According to the result, the PEMF with 38 Gauss, 100 Hz was very effective in the healing of bone defect and new bone formation. So The PEMF will be useful in clinical aspect for oseteogenesis.
Electromagnetic Fields* ; Heating ; Hot Temperature ; Magnetic Fields ; Magnets* ; Osteogenesis* ; Sutures ; Transplants

BACKGROUND: This work presents an experimental and modeling study of the electromagnetic environment in the vicinity of a high voltage substation located in eastern Algeria (Annaba city) specified with a very high population density. The effects of electromagnetic fields emanating from the coupled multi-lines high voltage power systems (MLHV) on the health of the workers and people living in proximity of substations has been analyzed. METHODS: Experimental Measurements for the Multi-lines power system proposed have been conducted in the free space under the high voltage lines. Field's intensities were measured using a referenced and calibrated electromagnetic field meter PMM8053B for the levels 0 m, 1 m, 1.5 m and 1.8 m witch present the sensitive's parts as organs and major functions (head, heart, pelvis and feet) of the human body. RESULTS: The measurement results were validated by numerical simulation using the finite element method and these results are compared with the limit values of the international standards. CONCLUSION: We project to set own national standards for exposure to electromagnetic fields, in order to achieve a regional database that will be at the disposal of partners concerned to ensure safety of people and mainly workers inside high voltage electrical substations.
Algeria ; Electromagnetic Fields ; Heart ; Human Body ; Humans ; Magnetic Fields* ; Magnets ; Methods ; Pelvis ; Population Density

OBJECTIVES: Several studies have raised the possibility that exposure to electrical and/or magnetic fields may be particularly harmful in the promotion or initiation of cancer. The purpose of this study which was based on a geographical correlation design was to investigate any association that may exist between residing near radio broadcast towers and carcinogenic activity in Korea. METHODS: In this study, the health effects of EMF of 10 AM radio broadcast towers in Korea were investigated. The electric powers of the towers were above 100kW. We chose exposed areas that were located within 2 km from the towers as well as four control regions which had similar populations in the same province(Do) but had no towers nearby. The incidence of leukemia, malignant lymphoma, brain tumor and breast cancer between the exposed areas and the control areas was compared. The standardized incidence ratios(SIRs) were calculated. Korean Medical Insurance data(between Nov,1,1993 and Oct,31,1996) was used for the cancer incidence estimation. The Nationwide Population Census data(in 1995) and the Resident Register data(in 1995) were used for information about population and locations. RESULTS: Among the 10 exposed areas, one area for leukemia and one area for brain tumor showed a significantly high incidence compared to the control areas. There were no significant increased areas for malignant lymphoma and breast cancer. CONCLUSIONS: This study design must be considered to be exploratory and not used for determining causality. However, the results suggest the necessity for further analytical epidemiological studies that have a more precise exposure measurement scale and information on confounding factors.
Brain Neoplasms ; Breast Neoplasms ; Censuses ; Electromagnetic Fields ; Epidemiologic Studies ; Incidence* ; Insurance ; Korea ; Leukemia ; Lymphoma ; Magnetic Fields

PURPOSE: We use many electronic devices for treating patients in our emergency department. Several studies have reported an association between electromagnetic field exposure and risk of cancer and other diseases. Our purpose was to measure the intensity of power-frequency magnetic fields in the emergency department and evaluate the conditions exceeded regulation guidelines for power-frequency magnetic fields. METHODS: Extremely low frequency magnetic fields were measured at 78 ordinary working spots in our tertiary hospital's emergency department (ED) and evaluated according to national regulatory guidelines and SWEDAC. Each spot was measured four times. During measurement, every electrical device in the emergency department was turned on. RESULTS: The average intensity of the magnetic fields in our emergency department was 0.99+/-1.27 mG. The maximum intensity was 8.3 mG, which was found in the pediatric section. CONCLUSION: The power-frequency magnetic field intensities of the various sections of our ED did not exceed national regulatory guidelines. However, pediatric and the minor emergency section showed magnetic fields intensities far above 2 mG. We found these high values outside the pediatric and waiting sections, where the electrical cabinet panel was located. We conclude that the electrical cabinet panel should be shielded and that similar studies are needed for other emergency departments.
Electromagnetic Fields ; Electronics ; Electrons ; Emergencies ; Emergency Service, Hospital ; Environmental Exposure ; Humans ; Magnetic Fields ; Magnetics ; Magnets