29/09/2014
Dosimetric Study of Fetal Exposure to Uniform Magnetic Fields at 50 Hz
Ilaria Liorni, Marta Parazzini, Serena Fiocchi, Mark Douglas, Myles Capstick, Marie-Christine Gosselin, Niels Kuster, and Paolo Ravazzani, Bioelectromagnetics, Volume 35, Issue 8, pp. 580–597, online September 29, 2014
In this study, numerical modeling was used to analyze the exposure of fetuses at three different gestational ages (GA) to uniform magnetic fields at 50 Hz power line frequencies with different polarizations. Fetal whole-body and tissue-specific induced electric fields (E) and current densities (J) were analyzed as a function of both magnetic field polarization and GA. Particular emphasis was placed on choosing the tissue parameters to be used in these fetal models, and a full survey of the relevant literature was performed. In addition, induced field variations due to changes in fetal position were analyzed by means of two new pregnant models. The uncertainty budget due to the grid resolution has also been calculated.
Finally, the compliance of the fetal exposure with the ICNIRP Guidelines has been checked. A fetal exposure matrix at 50 Hz, which could be used to further investigate possible interaction mechanisms between ELF-MF and health risk, has been built. In summary, the induced fields increase with GA; the E and J maxima were found in skin and fat tissues for all GA; fetal tissue-specific exposure is modified as a function of GA and field polarization.
The scientific and technical impact of the study can be summarized as:
- The study was performed with highly detailed anatomical models.
- Changes of the position of the fetus in a woman’s womb modifies significantly the induced E in some fetal tissues.
- The induced fields are in compliance with the ICNIRP Guidelines and well below the permitted threshold limit.