Inhibition of proliferation of human lymphoma cells U937 by a 50 Hz electromagnetic field

Weak pulsating electromagnetically induced fields (PEMF) by Helmholtz coils changes cell metabolism, if cells are treated with a certain range of frequency and amplitude. The influence on proliferation of human histiocytic lymphoma cells U937 has been studied applying a sinusoidal 50 Hz field with amplitudes of the flux density B = 0.3 to 4.7 mT for 4 days. No difference between experiment and control was found in the region 0.3 and 2 mT. However, stronger fields (> or =2.5 mT) inhibit cell division. Fields > or =3.5 mT treatment kill > or =80% of the cell number at the beginning (1.5 x 10(5)/ml). This effect may be an electromagnetocally induced cell death as the first step for a non-invasive application on cell proliferation process.