Effects of 50 Hz EMF on the cancel cell after 24h and 72h of exposure. (A) After 24h of exposure. (B) After 72h of exposure. The histogram of effects of 50 Hz EMF on human breast cancer cell line MDA-MB-231 and colon cancer cell lines HCT-116 and SW-480. The antiproliferative effect was measured by MTT assay after 24 h of exposure. All values are mean ± SEM, n = 3, *p < 0.05 as compared with control (100%).