Background: During the recent years a large number of microwave radiating appliances, e.g. cell phone, radio, television, electric home appliances, etc, have been produced and used in a wide range. Therefore ٫ researchers in biology have paid special attention to the effects of the waves on the human health and the animal growth process. This research studies the effects of the cell phone waves (940 MHz) on the hematopoietic system of immature Balb/C mice.

Materials and Methods: In this experimental research a microwave generating system (940 MHz) consisting of a special cage with two built-in cell phones was used. Immature mice were exposed to the waves of two active cell phones for 30 min /daily for a period of fifteen days. Having completed the feeding and caring process ٫ the mice from three control, sham-exposed and experimental groups were dissected. To assay blood parameters, blood was taken from the heart and to carry out the histological studies, spleen, liver and bone marrow were prepared for light microscopy studies. The quantitative data were analyzed with SPSS software and one-way ANOVA with the consideration of the significant level of p<0.05.

Results : The cell phone waves (940MHz) have no significant effect on the number of WBC, Hb, MCV, MCH, MCHC (p>0.05). While a decrease in the number of white pulp lymphocytes, and megakaryocytes in the experimental samples were seen compared to the control and sham-exposed groups (p≤0.001), the number of white pulp, spleen diameter and diameter of white pulp had no significant difference in control and sham-exposed and experimental groups (p>0.05). In the liver of experimental mice, the number of mononuclear cell complexes and Kupffer cells had a significant decrease compared to the control group (p≤0.001). The number of hepatocytes in both control and experimental groups showed no significant difference (p>0.05).There was an increase in the mean number of bone marrow cells and their division compared to the control samples (p≤0.001).

Conclusion : The cell phones waves have an effect on some cells of liver, spleen and bone marrow in immature BALB/c mice.