Dosimetric study of fetal exposure to uniform magnetic fields at 50 Hz

In this paper, fetal exposure to uniform magnetic fields (MF) with different polarizations is quantified at 50 Hz. Numerical computations were performed on high-resolution pregnant models at 3, 7 and 9 months of gestational age (GA), that distinguish a high number of fetal tissues. Fetal whole-body and tissue-specific induced electric fields (E) and current densities (J) are analyzed as a function of both the extremely low frequency magnetic field (ELF-MF) polarization and GA. Additionally, the induced field variations due to changes in fetal position has been analyzed by means of two new pregnant models. The uncertainty budget due to the grid resolution has been also calculated. Finally, the compliance of the fetal exposure to the ICNIRP Guidelines has been checked. A fetal exposure matrix has been built at 50 Hz, which could be used to further investigate possible interaction mechanisms between ELF-MF and health risk. Some specific findings are: 1) the induced fields increase with GA; 2) the maxima E were found in skin and fat tissues at each GA; 3) fetal tissue-specific exposure is modified as a function of GA and of the polarization; 4) the change of the fetal position in woman's womb modifies significantly the induced E in some fetal tissues; 5) the induced fields are in compliance to the ICNIRP Guidelines and result quite below the permitted threshold limit.