Continuous exposure to a uniform ELF-EMF promotes cell proliferation in HeLa and IMR-90 cells.

<p>(A, C) HeLa and IMR-90 cells were exposed continuously to a 6 mT ELF-EMF for up to 72 h. Cell viability was assessed by MTT assays every 24 h and evaluated as a percentage relative to the viability of unexposed cells (0 h). (B, D) After 72 h of ELF-EMF exposure, HeLa and IMR-90 cells were detached and further subcultured in an ELF-EMF of the same strength for up to 96 h. For the recovered group, cells exposed for 72 h were detached and subcultured without any further EMF exposure. Cell viability was assessed by MTT assays every 24 h and relative cell viability was evaluated as to the viability of 72 + 24 h cells. Data were plotted as the mean ± SD (n = 3). P-values were determined by two-way ANOVA with the Bonferroni correction. Values of *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001 were considered statistically significant, and P > 0.05 was considered statistically not significant (ns).