Study of the Cardiovascular Effects of Exposure to Electromagnetic Field

This study was conducted to throw light on electromagnetic radiofrequency (EMR) emitted from cell phones which was accused of causing a number of negative health effects in the form of influencing on the heart and circulatory system. 110 adult albino rats, of both sexes, weighing 180200 gms were used in the present study. Animals were allocated into two main groups: group I, including rats exposed to cell phone EMF for 4 weeks; and group II, including rats exposed to EMF for 8 weeks. Each group was further subdivided into four subgroups, a control group and three subgroups exposed to EMF for either 1h/day, 2hrs/day or 3hrs/day, exposure being carried out six days/ week, at fixed time of the day. All rats were subjected to measurement of the systolic blood pressure on the day prior to the day of sacrifice, ECG recording, assessment of cardiac weights, absolute& relative, and MDA level in cardiac tissue, as well as determination of plasma renin activity, plasma total antioxidant capacity and plasma calcium level. Specimens from the apex of the heart were subjected to histopathological examinations. Obtained results revealed that systolic blood pressure was significantly increased in all EMF-exposed rats compared to their respective controls. The heart rate, deduced from the ECG tracings, was non-significantly altered in all groups exposed to EMF for 4 weeks and in the 8 weeks-1hr/day exposure group, but was significantly reduced in rats exposed to EMF for 2hrs or 3hrs/day for 8 weeks. The ECG recording of rats exposed to EMF for 4 weeks revealed a significantly higher R voltage in the group exposed for 3hrs/day, a significant increase in QRS duration in the groups exposed for 2hrs and 3hrs/day and significant prolongation of QT-c interval in the group exposed for 3hrs/day. On the other hand, the ECG recording of rats exposed to EMF for 8 weeks revealed significantly higher R and T voltages, and significantly prolonged P-R and QT-c intervals in the groups exposed for 2hrs or 3hrs/day, the QRS duration being significantly increased in all the 8 weeksexposed groups. In addition, a significant increase in the absolute and relative weights of the whole heart and of the left ventricle in rats exposed to EMF 2hrs or 3hrs/day for either 4 or 8 weeks was obtained. Plasma renin activity was increased in all exposed rats, the increase being statistically significant in rats exposed to EMF 3hrs/day for 4 weeks, and in all the groups exposed to EMF for 8 weeks. Plasma calcium level was significantly decreased in all the exposed groups except for the group exposed for 1hr/day for 4 weeks. The plasma total anti-oxidant capacity was significantly decreased in all exposed groups, for either 4 or 8 weeks, while the MDA level in the cardiac tissue was only significantly elevated in the 8 weeks3hrs/day exposed group compared to the matched control group. The histopathological examination revealed hypertrophy, fragmentation and vacuolation of the myocardium, which were directly proportional to the exposure time. On conclusion, long-term exposure to cell phone EMF increases the liability for hypertension reflected on the ECG and cardiac weights which is accompanied by histopathological changes in the myocardium. In addition, an interaction of EMF with biological functions was achieved in the form of increased PRA, decreased plasma total antioxidant capacity and hypocalcemia. [Fatma A. Mohamed, Azza A. Ahmed, Bataa M.A. ElKafoury, & Noha N. Lasheen. Study Of The Cardiovascular Effects Of Exposure To Electromagnetic Field. Life Science Journal. 2011;8(1):260-274] (ISSN:1097–8135). http://www.lifesciencesite.com.