Specific Absorption Rate Variability in Long Term Exposure In Vivo Experiments

There is no specific methodology for exposing animals to non-ionizing electromagnetic fields, especially regarding the technical setup, the generator parameters, and the duration of exposure. The scientific literature displays a vast range of experiment designs and technical setups when scrutinized. Most studies that examine the biological effects of non-ionizing electromagnetic exposure use laboratory setups that address the controllability aspect, therefore having strict parameters. On the other hand, the relevance of these laboratory experiments with respect to real-life exposure scenarios is reduced for the sake of controllability and replicability, differing from environmental exposure to radiofrequency radiation in real-life settings. Recent reviews indicate that real-life signals are more bioactive, meaning that the high and unpredictable variability of real-life exposure sources (represented by telecommunication devices) induce stronger biological effects. Another aspect of in vivo experiments on animals using long-term exposure is that any motion restriction induces a significant animal stress in the long run, especially for experiments lasting months or years. Therefore, long-term exposure setups must allow the free movement of laboratory animals, which only adds to its variability. One of the quality criteria imposed to in vivo animal exposure is accurate dosimetry. It is the scope of this paper to discuss the variability of the specific absorption rate in long-term exposure of in vivo experiments on animals with respect to the animal’s position in the electromagnetic fields.