03/11/2014
Quantification of RF-Exposure of the Fetus Using Anatomical CAD-Models in Three Different Gestational Stages
Eugenia Cabot, Andreas Christ, Barbara Bühlmann, Marcel Zefferer, Nicolas Chavannes, Jurriaan F. Bakker, Gerard C. van Rhoon, and Niels Kuster, Health Physics, Volume 107, Issue 5, pp. 369–381, online November 2014
In this study, numerical modeling was used to analyze the exposure of pregnant women and their fetuses at three different gestational stages to electromagnetic radiation in the radio frequency range in the near and the far-field. For far-field exposure, the power density at which the basic restriction for the wholebody SAR is reached was calculated for both the mother and the fetus at whole body resonance and at frequencies of 450 – 2450 MHz. The near-field exposure was assessed at 450, 900, and 2450 MHz, with half wavelength dipoles as generic sources located at various locations around the abdomen of the mother. For the investigated cases, the exposure of the mother is always lower than or of the same order of magnitude of the basic restriction for exposure at the reference level.
At the reference levels for exposure of the general public, the fetus is sufficiently shielded by the mother. However, the basic restrictions for general public exposure can be exceeded in the fetus when the mother is exposed at reference levels for occupational conditions. For plane wave exposure at occupational levels, the whole body SAR in the fetus can exceed the basic restrictions for the general population by at least 1.8 dB, and in the near-field of professional devices, the 10 g SAR can be non-compliant with the product standard for the general public by > 3.5 dB.
The scientific and technical impact of the study can be summarized as:
- The study was performed with highly detailed anatomical models.
- The reference levels can be considered conservative with respect to the basic restrictions if either occupational or uncontrolled limits apply for both mother and fetus.
- The exposure of the mother at reference levels for occupational conditions may result in the fetus exposed to levels above the basic restrictions.