Research Product

Sheepshead minnows (Cyprinodon variegatus) were reared in a reference aquarium and in an aquarium within a 60-Hz electromagnetic field (EMF) in a 156 day preliminary experiment. Modified Helmholtz coils surrounding the exposure aquarium generated a horizontal 1.0 to 1.25 mT rms magnetic field throughout the water volume. Two groups of fish and samples of their embryos were exposed in overlapping exposure periods. Fish in Group I grew from juveniles to reproducing adults during 54 days of exposure. Exposure of Group II began with artificially spawned embryos that hatched and grew to reproducing adults while exposed for 137-152 days. Naturally spawned progeny from both groups were incubated to hatching in the same saltwater aquaria as parents. Although some significant effects (a=0.05) on test endpoints were observed between treatments, they were not consistently significantly different across exposure groups, life stages, et cetera. No behavioral and histopathological effects related to the EMF were observed.