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Study of the influence of the orientation of a 50-Hz magnetic field on fetal exposure using polynomial chaos decomposition.

Liorni I, Parazzini M, Fiocchi S, Ravazzani P - Int J Environ Res Public Health (2015)

Bottom Line: PC theory resulted in an efficient tool to build accurate approximations of E in each fetal tissue.B orientation strongly influenced E, with a variability across tissues from 10% to 43% with respect to the mean value.However, varying B orientation, maximum E in each fetal tissue was below the limits of ICNIRP 2010 at all GAs.

View Article: PubMed Central - PubMed

Affiliation: CNR Consiglio Nazionale delle Ricerche, Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni IEIIT, Piazza Leonardo da Vinci 32, Milan 20133, Italy. ilaria.liorni@ieiit.cnr.it.

ABSTRACT
Human exposure modelling is a complex topic, because in a realistic exposure scenario, several parameters (e.g., the source, the orientation of incident fields, the morphology of subjects) vary and influence the dose. Deterministic dosimetry, so far used to analyze human exposure to electromagnetic fields (EMF), is highly time consuming if the previously-mentioned variations are considered. Stochastic dosimetry is an alternative method to build analytical approximations of exposure at a lower computational cost. In this study, it was used to assess the influence of magnetic flux density (B) orientation on fetal exposure at 50 Hz by polynomial chaos (PC). A PC expansion of induced electric field (E) in each fetal tissue at different gestational ages (GA) was built as a function of B orientation. Maximum E in each fetal tissue and at each GA was estimated for different exposure configurations and compared with the limits of the International Commission of Non-Ionising Radiation Protection (ICNIRP) Guidelines 2010. PC theory resulted in an efficient tool to build accurate approximations of E in each fetal tissue. B orientation strongly influenced E, with a variability across tissues from 10% to 43% with respect to the mean value. However, varying B orientation, maximum E in each fetal tissue was below the limits of ICNIRP 2010 at all GAs.

No MeSH data available.


Related in: MedlinePlus

Distribution of B-field orientations on a unitary sphere represented in the pregnant woman’s reference system x,y,z (Figure 2), which determine, on the fetus whole-body at nine months GA, induced electric field E99th in the ranges explained in Figure 6. The B orientations have been also indicated with respect to the reference system centered on the pregnant woman adopted in this study.
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ijerph-12-05934-f008: Distribution of B-field orientations on a unitary sphere represented in the pregnant woman’s reference system x,y,z (Figure 2), which determine, on the fetus whole-body at nine months GA, induced electric field E99th in the ranges explained in Figure 6. The B orientations have been also indicated with respect to the reference system centered on the pregnant woman adopted in this study.

Mentions: Finally, Figure 6, Figure 7 and Figure 8 represent the distribution on a unitary sphere of those B orientations, among the 10,000 analyzed, which induce E99th higher than 70% of mE99th in the fetus whole-body at 3, 7 and 9 months GA. In detail, in the figures, the blue circles represent the B orientations for which E99th in the fetus whole-body is in the range from 70% to 79% of mE99th, the green circles in the range from 80% to 89% of mE99th and the red circles all of the orientations of the B-field for which E99th is higher than 90% of mE99th.


Study of the influence of the orientation of a 50-Hz magnetic field on fetal exposure using polynomial chaos decomposition.

Liorni I, Parazzini M, Fiocchi S, Ravazzani P - Int J Environ Res Public Health (2015)

Distribution of B-field orientations on a unitary sphere represented in the pregnant woman’s reference system x,y,z (Figure 2), which determine, on the fetus whole-body at nine months GA, induced electric field E99th in the ranges explained in Figure 6. The B orientations have been also indicated with respect to the reference system centered on the pregnant woman adopted in this study.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4483680&req=5

ijerph-12-05934-f008: Distribution of B-field orientations on a unitary sphere represented in the pregnant woman’s reference system x,y,z (Figure 2), which determine, on the fetus whole-body at nine months GA, induced electric field E99th in the ranges explained in Figure 6. The B orientations have been also indicated with respect to the reference system centered on the pregnant woman adopted in this study.
Mentions: Finally, Figure 6, Figure 7 and Figure 8 represent the distribution on a unitary sphere of those B orientations, among the 10,000 analyzed, which induce E99th higher than 70% of mE99th in the fetus whole-body at 3, 7 and 9 months GA. In detail, in the figures, the blue circles represent the B orientations for which E99th in the fetus whole-body is in the range from 70% to 79% of mE99th, the green circles in the range from 80% to 89% of mE99th and the red circles all of the orientations of the B-field for which E99th is higher than 90% of mE99th.

Bottom Line: PC theory resulted in an efficient tool to build accurate approximations of E in each fetal tissue.B orientation strongly influenced E, with a variability across tissues from 10% to 43% with respect to the mean value.However, varying B orientation, maximum E in each fetal tissue was below the limits of ICNIRP 2010 at all GAs.

View Article: PubMed Central - PubMed

Affiliation: CNR Consiglio Nazionale delle Ricerche, Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni IEIIT, Piazza Leonardo da Vinci 32, Milan 20133, Italy. ilaria.liorni@ieiit.cnr.it.

ABSTRACT
Human exposure modelling is a complex topic, because in a realistic exposure scenario, several parameters (e.g., the source, the orientation of incident fields, the morphology of subjects) vary and influence the dose. Deterministic dosimetry, so far used to analyze human exposure to electromagnetic fields (EMF), is highly time consuming if the previously-mentioned variations are considered. Stochastic dosimetry is an alternative method to build analytical approximations of exposure at a lower computational cost. In this study, it was used to assess the influence of magnetic flux density (B) orientation on fetal exposure at 50 Hz by polynomial chaos (PC). A PC expansion of induced electric field (E) in each fetal tissue at different gestational ages (GA) was built as a function of B orientation. Maximum E in each fetal tissue and at each GA was estimated for different exposure configurations and compared with the limits of the International Commission of Non-Ionising Radiation Protection (ICNIRP) Guidelines 2010. PC theory resulted in an efficient tool to build accurate approximations of E in each fetal tissue. B orientation strongly influenced E, with a variability across tissues from 10% to 43% with respect to the mean value. However, varying B orientation, maximum E in each fetal tissue was below the limits of ICNIRP 2010 at all GAs.

No MeSH data available.


Related in: MedlinePlus