Effects of MR exposure at 1.5 T on early embryonic development of the chick.

The potential teratogenicity of magnetic resonance (MR) field exposure on the early development of the chick embryo was examined. Eggs at four developmental stages within the first 42 hours of incubation were exposed to a static magnetic field of 1.5 T for 6 hours and to 64-MHz radio-frequency field pulses and a switched magnetic field gradient with an amplitude of 0.6 G/cm for 4 h. When the embryos were sacrificed shortly thereafter (at approximately 53 hours of incubation), the abnormality and mortality rates of exposed and unexposed (control) embryos in each of the developmental groups did not show a consistent pattern. When embryos were sacrificed on the 6th day of incubation, exposed embryos from all developmental groups showed a trend toward higher abnormality and mortality rates than their controls. More extensive studies are needed to confirm these findings.