Growth stage dependent effects of electromagnetic fields on DNA synthesis of Jurkat cells.

A 1.8 mT, bone healing, electromagnetic field (EMF) and power frequency EMFs of 0.1 and 0.4 mT significantly inhibit DNA synthesis in otherwise unstimulated Jurkat (E 6.1) cells. Inhibition is generally most prominent in cells from mid log phase growth. In complete medium the bone healing EMF inhibits [3H] thymidine uptake of the latter cells by almost 50% vs. 20-25% inhibition by 60 Hz fields. Cells in conditioned medium are even more sensitive to EMFs with inhibition up to ca. 60%. The effects of the 0.1 and 0.4 mT power frequency EMFs were very similar suggesting saturation at 0.1 mT or lower.