High-resolution organ dosimetry for human exposure to low-frequency electric fields

Evaluation of the fields induced in the human body, provides a means of quantification of various exposures to lowfrequency electric and magnetic fields. A new hybrid numerical method is used to compute these quantities, generated in an anatomically-based high-resolution human body model, by lowfrequency uniform electric fields. The hybrid method combines scalar-potential finite-difference and quasistatic finite-difference timedomain methods, and is capable of accurately computing the induced fields in a full-body model composed of 1 736 872 cubic voxels with 3.6-mm edges. Results specific to various organs are given for exposure to 60-Hz fields, with the body model in three positions relative to a ground-plane. The effect of tissue conductivity is investigated. The data presented can be linearly scaled to frequencies up to 100 kHz without appreciable error, provided that changes of tissue conductivity with frequency are taken into account. Evaluations such as the present one should prove useful in the development of protection standards, and are also expected to aid in the understanding of results from various animal and tissue culture studies.