Design and Dosimetric Analysis of a Whole-Body Exposure Setup for Investigating Possible Effects of 50 Hz Magnetic Fields on Sleep and Markers of Alzheimer's Disease.

A new whole-body exposure facility for a randomized, double-blind, cross-over provocation study investigating possible effects of 50 Hz magnetic field exposure on sleep and markers of Alzheimer's disease has been developed and dosimetrically analyzed. The exposure facility was custom-tailored for the sleep laboratory where the study was carried out and enables magnetic flux densities of up to 30 μT with a maximum field inhomogeneity of less than ± 20%. Exposure is applied fully software-controlled and in a blinded and randomized manner. The orientation of the applied magnetic field vector is varied by the control software to create a uniformly distributed set of field vector orientations throughout each experimental session. A numerical dosimetric analysis of the exposure facility was carried out using several high-resolution anatomical body models. Induced electric field strengths in the range of 0.5-0.6 mV/m (99.9th percentile of 2 × 2 × 2 mm3 averaged induced electric field strength Ei) inside the brain at an external exposure level of 30 μT were obtained for magnetic field vector orientations along the three main axes (front-back, left-right, head-feet). Statistics of volume averaged values of Ei, analyzed for several hundred different brain regions of gray matter, under exposure with varying magnetic field vector orientations yield value ranges of 0.001-0.065 mV/m (minima), 0.025-0.21 mV/m (mean values), and 0.033-0.34 mV/m (maxima). The developed exposure facility was successfully deployed in a recently completed experimental study. Bioelectromagnetics. 00:00-00, 2025.