The effects of a static magnetic field on DNA synthesis and survival of mammalian cells irradiated with fast neutrons

The effects of a static magnetic field (0.75 T) on DNA synthesis and survival were examined with Chinese hamster V79 cells in cultures with and without fast‐neutron irradiation. We found that the magnetic field applied alone for up to several hours did not cause a significant effect in either the rate of DNA synthesis or cell viability; the latter was assayed by colony formation. When cells were exposed simultaneously to the magnetic field and fast neutrons, the effects resembled those observed with neutrons alone. This was the case for both inhibition of DNA synthesis and cell killing. Cells irradiated first with neutrons followed immediately by 1 h of magnetic field exposure showed a dose‐survival response curve indistinguishable from that of neutrons alone. These data suggest that the biological effect due to the magnetic field is negligible and that the presence of the magnetic field either during or subsequent to fast‐neutron irradiation does not affect the neutron‐induced radiation damage or its repair. © 1987 Academic Press, Inc.