[Myocardial infarct and geomagnetic disturbances: analysis of data on morbidity and mortality]. / Infarkt miokarda i geomagnitnye vozmushcheniia: analiz dannykh o zabolevaemosti i smertnosti.

Relationships between different parameters of the geomagnetic activity and medical statistical data on myocardial infarction were investigated anew, because previous results in this field have been often inconsistent. The data are daily numbers of myocardial infarction incidence rates (15,543 cases) and number of deaths for infarction (3,065 cases), abstracted from registries of the 14 biggest hospitals of St. Petersburg (1989-1990). The analysis showed a statistically significant increase in myocardial infarction rate during big geomagnetic disturbances, defined by the days of the descending phase of cosmic ray Forbush decreases. An overall estimation of the average increase in infarction incidence rate during big geomagnetic storms, (10.5 +/- 1.2)%, has been computed by taking into account previous results [1-3]. In contrast, morbidity data did not show any significant correlation with geomagnetic disturbances. It was found also that the infarction incidence rate appears to be rather constant from Monday to Friday and to decrease sharply by a factor approximately 1.25 on Saturday-Sunday and mid-week festivities. This effect is associated with different exposure during work days and week-ends to man-made magnetic field environment mainly produced by electrified transport. Such effect was not observed in mortality data. The results and their methodological aspects are placed in the context of studies on possible health effects of low frequency magnetic fields both natural and man-made origin.

[Electric traction magnetic fields of ultra-low frequency as an occupational risk factor of ischemic heart disease]. / Ul'tranizkochastotnye magnitnye polia ot élektrotiagi kak professional'nyi faktor riska ishemicheskoi bolezni serdtsa.

The study was inspired by earlier results that displayed influence of variable natural geomagnetic field (0.005-10 Hz range-ultra-low frequencies) on circulatory system, indicated possible correlation between industrial ultra-low frequency fields and prevalence of myocardial infarction. The authors conducted unique measurements of ultra-low frequency fields produced by electric engines. The results were compared with data on morbidity among railway transport workers. The findings are that level of magnetic variations in electric locomotive cabin can exceed 280 micro Tesla, whereas that in car sections reaches 50 micro Tesla. Occurrence of coronary heart disease among the locomotive operators appeared to be 2.0 + 0.2 times higher than that among the car section operators. Higher risk of coronary heart disease in the locomotive operators is associated with their increased occupational magnetic load.

[Effect of electromagnetic fields of natural and anthropogenic origin on the frequency of pathology occurrence in St. Petersburg]. / Vliianie élektromagnitnykh polei estestvennogo i antropogennogo proiskhozhdeniia na chastotu proiavleniia razlichnykh patologii v Sankt-Peterburge.

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.