Charge Relaxation in Biological Tissues with Extremely High Permittivity

This letter presents a phenomenological model to describe charge relaxation (and the corresponding screening effect) in biological tissues, i.e., lossy dielectrics where a non-negligible conductivity and an extremely high relative permittivity (on the order of 50 × 10
⁶
) may coexist. This situation is very peculiar and is not treated in textbooks. The model is used to study an open issue in electromagnetic dosimetry, namely the effect of charge relaxation on the motion-induced electric fields in the bodies of the operators working in magnetic resonance imaging environments.