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[Effect of electromagnetic fields of natural and anthropogenic origin on the frequency of pathology occurrence in St. Petersburg].

The effect of man-made electromagnetic fluctuations and strong geomagnetic disturbances on human pathology-data from St. Petersburg (Russia, 1981) is analyzed. The most remarkable effect is the 7-day variation of the ambulance-call data for myocardial infarction, that show a decrease in pathology-rate (70%) during week-ends and public holidays. Results of measurement of man-made electromagnetic fluctuations in the frequency range 0.005-10 Hz in 1991 and 1994 show a big decrease in electromagnetic noise during week-ends. We suggest that very big 7-day variation in infarction rates is connected with the decrease of electromagnetic noise during Saturdays-Sundays. This phenomenon is responsible for the very big 7-day variation in infarction rate. The myocardial infarction rate cleaned up by meteorological and social effects show the increasing by a factor 1.14 during geomagnetic storms.

Electromagnetic Fields↗
PubMed2006

Spatial correlation functions of inhomogeneous random electromagnetic fields.

We analyze the influence of an infinite planar perfectly conducting surface on the spatial correlation functions of a random quasimonochromatic classical electromagnetic vector field, based on a TE/TM decomposition of an angular spectrum of random plane waves. The presence of the surface causes the correlation to depend on both the absolute and relative locations of the field points (inhomogeneous correlation). Known asymptotic results for statistically homogeneous random free fields are retrieved as special cases. The analytical results are illustrated with computations for separations that are either perpendicular or parallel to the surface. The correlation distance for any field component exhibits a damped oscillatory dependency on the local center point. A geometric interpretation in terms of fluctuations of correlation cells is given.

Journal Article↗
PubMed2005

Can electromagnetic fields emitted by mobile phones stimulate the vestibular organ?

OBJECTIVES: Pulsating electromagnetic (EM) radiation emitted by mobile phones is often incriminated for causing tissue alterations by caloric effects. In particular, the eye and the ear were regarded as possible "hot spots," with heating up to 1 degree C, in which EM radiation might have negative effects. If so, these temperature increments should be large enough to cause vestibular excitation. In this study, we attempted to verify this theory by clinical testing and in vitro experiments. METHODS AND MEASURES: In our laboratory, a simulated GSM signal (889.6 MHz/2.2 W) was applied to 1 ear at a time, while video nystagmography was performed. The experimental setup was similar to that used for caloric (hot and cold water) testing of the peripheral vestibular organ. Data were evaluated by a computer system. There were 13 volunteers (26 ears) included in our study. In an additional experiment, temperatures of human temporal bones were measured by thermography, while a continuous or pulsating EM field was applied. RESULTS: In no volunteer could EM radiation-induced nystagmus be recorded. This corresponds well to our findings that in the human temporal bone very weak caloric effects could only be found in the tissue layers next to the radiation source (antenna of the mobile phone), whereas deeper regions (horizontal semicircular canal) seemed unaffected (at least less than 0.1 degree C). CLINICAL SIGNIFICANCE: These results do not support the theory that mobile phone-induced EM radiation may cause caloric negative effects in the human ear.

Adult↗
PubMed1992

Radio-frequency electromagnetic fields associated with cellular-radio cell-site antennas.

Because of a heightened public awareness of issues pertaining to the use of electromagnetic energy, concurrent with a rapid growth of the cellular telephone industry, a study was initiated to characterize the electromagnetic environment associated with typical cell-site antennas. In particular, the radio-frequency electromagnetic (RF) fields in the vicinity of several antenna towers, ranging in height from 46-82 m, were characterized by measurement. In all cases, the antennas were omnidirectional co-linear arrays. The maximal power densities considered representative of public exposure were found to be less than 100 microW/m2 (10 nW/cm2) per radio channel. Comparison of measured values with the corresponding values that were calculated from the free-space transmission formula indicated that the analytical technique is conservative (i.e., overestimates field levels). The measured and corresponding analytical values were found to be well below accepted exposure limits even when extrapolated to simultaneous and continuous operation of the maximal number of transmitters that would be expected to be installed at a cell-site. Additional measurements were made in the near field of the same antenna type in a roof-mounted configuration. At a distance of 0.7 m from the antenna, the maximal power density in the main beam was found to be less than 30 W/m2 (3 mW/cm2) when normalized to sixteen radio channels (the maximal number used on a single antenna) and less than 30 mW/m2 (3 microW/m2) at 70 m. In all cases, the effective radiated power (ERP) by each radio channel was 100 W referenced to a half-wave dipole. This paper describes the instrumentation and measurement techniques used for this study and provides a summary of the results.

Electromagnetic Phenomena↗