Fourty-eight newborn rats of five dams were randomly divided into three groups (n=16 per group): 1) control group, 2) sham exposure (kept in the incubator, but switched off) and 3) exposure group (kept in the incubator). Rat pups were kept together with their mothers. They were exposed for 15 days and examined when they were 1-month old.
|Exposure duration||continuously for 15 days|
|Setup||rats were exposed in a standard Plexiglas cage put inside the incubator with a mattress; cage was located at 36.8 cm from the left edge of the mattress where the magnetic flux density was highest|
|Sham exposure||A sham exposure was conducted.|
|Additional info||sham exposed rats were handled like the exposed ones, however, the incubator was switched off and noise was created by a air fan placed at a distance of 10 m|
Remark EMF-Portal: All statistical calculations in this article are based on the median.
In the Morris water maze, the amount of time for finding the platform was significantly increased in exposed rats (group 3) compared to sham exposed rats (group 2) and those from the control group (group 1). In the open field test, the duration at the central zone was significantly shorter in the exposed animals compared to groups 1 and 2. Furthermore, significantly less vertical movements, higher number of groomings (only significant compared to group 2), and a higher number of micturitions were observed in the exposed animals compared to groups 1 and 2 (if not stated otherwise). In the elevated plus maze, no significant differences in the staying duration in the open and closed arms was found between the groups. However, the number of groomings, defecations and micturitions was significantly higher in the exposed animals compared to groups 1 and 2.
The authors conclude that extremely low frequency magnetic fields of an incubator for newborns could have an adverse effect on anxiety and spatial learning in young rats.