Mean tumor volumes of control and treated mice, increasing intensity for constant time. A. Mean volume (mm3) of the murine 16/C breast adenocarcinoma tumor in control group and in the groups of mice exposed to 10, 15 or 20 mT EMF for 10 minutes once a day. Tumors were measured on day 8 just before the first exposure and again on days 10, 14, 17 and 20. ANOVA followed by SNK statistical analysis of group data (Table 2) revealed that by day 17 the tumors in the control group were significantly larger than the tumors of all treatment groups. B. Linear regression analyses of tumor volume at 17 days after implantation of mice receiving either 0, 10 15 or 20 mT EMF for 10 minutes per day illustrating the significant linear decrease in tumor volume with increasing EMF intensity.