Razi Journal of Medical Sciences

    Background & Aim: With regard to the reported biological effects of different frequencies of ELF as window effect and also the use of 217 Hz frequencies as  modulating radiofrequency waves of 900 MHz in global system for mobile(GSM), the purpose of this study was to investigate the effect of magnetic field of 217 Hz frequency on the growth of tumor cells.

Material and Method: Forty-nine male mice of Balb/c race aged  6-8 weeks were randomly divided into 7 groups (3 test groups, 3 sham groups, and a control group), and 100%, 75%, and 30% of minimum required cells in order to cause tumor were subcutaneously injected into them respectively. On the second day after injecting cells, test groups were exposed to the homogenous field of a pair of Helmholtz Coil for 150 minutes every day for 19 successive days.  The formation of tumors was observed after 6-10 days. On the twentieth day of the experiment, the mice were anesthetized and the tumors were extracted.Tissue samples were also gathered for histological comparison.

Results: This study was conducted experimentally and one-way ANOVA and SPSS-12 software were used to analyze and compare the weight and size of tumors in test groups in relation to sham groups. The study revealed that there was a significant difference (p<0.05) between test and sham groups regarding the size and weight of tumors. In terms of tumor formation, there was a significant difference between test and sham groups,too. Histological comparison did not show a significant difference regarding  mitosis and metastasis into other organs. However, mitosis in test groups was higher in comparison to sham groups, which is indicative of the presence of more active tumors in these groups. In addition, test groups' tumors had larger necrosis areas.

Discussion: The obtained results of this study show that exposure to  pulsed 217 Hz magnetic field can increase the development of the fibrosarcoma tumors in Balb/c mice, which is indicative of window effect according to the reports about other EFL frequencies.