Lack of effect of electric field exposure on rats: a data re-evaluation

Three recent investigations of the possible effects of to Hz electric fields on rats have yielded apparently contradictory results. While one group of investigators reported that chronic exposure to a 15 kV/m field caused several biological effects, the other two groups did not find these effects at 25 kV/m and 100 kV/m, respectively. A re-examination of the data from the 15 kV/m experiments indicates that the reported effects were probably artifacts due to improper statistical analysis and to a cage design which resulted in transient electric shocks (spark discharges) to the exposed rats. Hence, the results of all three investigations are consistent with a lack of biological effects from chronic exposure to 15--100 kV/m electric fields.