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1. Modeling the Spatial Distributions of Macro Base Stations with Homogeneous Density: Theory and Application to Real Networks

Author

Gontier, Q., Tsigros, C., Horlin, F., Wiart, J., Oestges, C., and De Doncker, P.

Subjects
Statistics - Applications
Abstract

Stochastic geometry is a highly studied field in telecommunications as in many other scientific fields. In the last ten years in particular, theoretical knowledge has evolved a lot, whether for the calculation of metrics to characterize interference, coverage, energy or spectral efficiency, or exposure to electromagnetic fields. Many spatial point process models have been developed but are often left aside because of their unfamiliarity, their lack of tractability in favor of the Poisson point process or the regular lattice, easier to use. This article is intended to be a short guide presenting a complete and simple methodology to follow to infer a real stationary macro antenna network using tractable spatial models. The focus is mainly on repulsive point processes and in particular on determinantal point processes which are among the most tractable repulsive point processes. This methodology is applied on Belgian and French cell towers. The results show that for all stationary distributions in France and Belgium, the best inference model is the $\beta$-Ginibre point process., Comment: EURO-COST CA20120 TD(22)0174

Published
2024

2. A Gaussian process based approach for validation of multi-variable measurement systems: application to SAR measurement systems

Author

Bujard, C., Neufeld, E., Douglas, M., Wiart, J., and Kuster, N.

Subjects
Statistics - Applications, Statistics - Computation
Abstract

Resource-efficient and robust validation of systems designed to measure a multi-dimensional parameter space is an unsolved problem as it would require millions of test permutations for comprehensive validation coverage. In the paper, an efficient and comprehensive validation approach based on a Gaussian Process (GP) model of the test system has been developed that can operate system-agnostically, avoids calibration to a fixed set of known validation benchmarks, and supports large configuration spaces. The approach consists of three steps that can be performed independently by different parties: 1) GP model creation, 2) model confirmation, and 3) targeted search for critical cases. It has been applied to two systems that measure specific absorption rate (SAR) for compliance testing of wireless devices and apply different SAR measurement methods: a probe-scanning system (per IEC/IEEE 62209-1528), and a static sensor-array system (per IEC 62209-3). The results demonstrate that the approach is practical, feasible, suitable for proving effective equivalence, and can be applied to any measurement method and implementation. The presented method is sufficiently general to be of value not only for SAR system validation, but also in a wide variety of applications that require critical, independent, and efficient validation.

Published
2022

3. On the distribution of scrambled $(0,m,s)$-nets over unanchored boxes

Author

Lemieux, C. and Wiart, J.

Subjects
Mathematics - Statistics Theory, 11K38, 65C05
Abstract

We introduce a new quality measure to assess randomized low-discrepancy point sets of finite size $n$. This new quality measure, which we call "pairwise sampling dependence index", is based on the concept of negative dependence. A negative value for this index implies that the corresponding point set integrates the indicator function of any unanchored box with smaller variance than the Monte Carlo method. We show that scrambled $(0,m,s)-$nets have a negative pairwise sampling dependence index. We also illustrate through an example that randomizing via a digital shift instead of scrambling may yield a positive pairwise sampling dependence index., Comment: 41 pages

Published
2020

4. Surrogate modeling based on resampled polynomial chaos expansions

Author

Liu, Z., Lesselier, D., Sudret, B., and Wiart, J.

Subjects
Statistics - Computation, Statistics - Methodology
Abstract

In surrogate modeling, polynomial chaos expansion (PCE) is popularly utilized to represent the random model responses, which are computationally expensive and usually obtained by deterministic numerical modeling approaches including finite element and finite-difference time-domain methods. Recently, efforts have been made on improving the prediction performance of the PCE-based model and building efficiency by only selecting the influential basis polynomials (e.g., via the approach of least angle regression). This paper proposes an approach, named as resampled PCE (rPCE), to further optimize the selection by making use of the knowledge that the true model is fixed despite the statistical uncertainty inherent to sampling in the training. By simulating data variation via resampling ($k$-fold division utilized here) and collecting the selected polynomials with respect to all resamples, polynomials are ranked mainly according to the selection frequency. The resampling scheme (the value of $k$ here) matters much and various configurations are considered and compared. The proposed resampled PCE is implemented with two popular selection techniques, namely least angle regression and orthogonal matching pursuit, and a combination thereof. The performance of the proposed algorithm is demonstrated on two analytical examples, a benchmark problem in structural mechanics, as well as a realistic case study in computational dosimetry.

Published
2018
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5. Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study

Author

Castaño-Vinyals, G., Sadetzki, S., Vermeulen, R., Momoli, F., Kundi, M., Merletti, F., Maslanyj, M., Calderon, C., Wiart, J., Lee, A.-K., Taki, M., Sim, M., Armstrong, B., Benke, G., Schattner, R., Hutter, H.-P., Krewski, D., Mohipp, C., Ritvo, P., Spinelli, J., Lacour, B., Remen, T., Radon, K., Weinmann, T., Petridou, E.Th., Moschovi, M., Pourtsidis, A., Oikonomou, K., Kanavidis, P., Bouka, E., Dikshit, R., Nagrani, R., Chetrit, A., Bruchim, R., Maule, M., Migliore, E., Filippini, G., Miligi, L., Mattioli, S., Kojimahara, N., Yamaguchi, N., Ha, M., Choi, K., Kromhout, H., Goedhart, G., 't Mannetje, A., Eng, A., Langer, C.E., Alguacil, J., Aragonés, N., Morales-Suárez-Varela, M., Badia, F., Albert, A., Carretero, G., and Cardis, E.

Published
2022
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6. Polynomial-Chaos-based Kriging

Author

Schoebi, R., Sudret, B., and Wiart, J.

Subjects
Statistics - Computation, Statistics - Methodology, Statistics - Machine Learning
Abstract

Computer simulation has become the standard tool in many engineering fields for designing and optimizing systems, as well as for assessing their reliability. To cope with demanding analysis such as optimization and reliability, surrogate models (a.k.a meta-models) have been increasingly investigated in the last decade. Polynomial Chaos Expansions (PCE) and Kriging are two popular non-intrusive meta-modelling techniques. PCE surrogates the computational model with a series of orthonormal polynomials in the input variables where polynomials are chosen in coherency with the probability distributions of those input variables. On the other hand, Kriging assumes that the computer model behaves as a realization of a Gaussian random process whose parameters are estimated from the available computer runs, i.e. input vectors and response values. These two techniques have been developed more or less in parallel so far with little interaction between the researchers in the two fields. In this paper, PC-Kriging is derived as a new non-intrusive meta-modeling approach combining PCE and Kriging. A sparse set of orthonormal polynomials (PCE) approximates the global behavior of the computational model whereas Kriging manages the local variability of the model output. An adaptive algorithm similar to the least angle regression algorithm determines the optimal sparse set of polynomials. PC-Kriging is validated on various benchmark analytical functions which are easy to sample for reference results. From the numerical investigations it is concluded that PC-Kriging performs better than or at least as good as the two distinct meta-modeling techniques. A larger gain in accuracy is obtained when the experimental design has a limited size, which is an asset when dealing with demanding computational models.

Published
2015

10. P122 - Association entre les marqueurs d'utilisation du téléphone dans la vie réelle et les performances cognitives à court terme, le bien-être et le sommeil

Author

Pujol, S., primary, Eeftens, M., additional, Klaiber, A., additional, Riss, A., additional, Smayra, F., additional, Flückiger, B., additional, Chopard, G., additional, Gehin, T., additional, Diallo, K., additional, Moussounda, N., additional, Wiart, J., additional, Mazloum, T., additional, Mauny, F., additional, and Röösli, M., additional

Published
2023
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13. A Gaussian-process-model-based approach for robust, independent, and implementation-agnostic validation of complex multi-variable measurement systems: application to SAR measurement systems

Author

Bujard, C., Neufeld, E., Douglas, M., Wiart, J., and Kuster, N.

Subjects
FOS: Computer and information sciences, Applications (stat.AP), Statistics - Applications, Statistics - Computation, Computation (stat.CO)
Abstract

Resource-efficient and robust validation of complex measurement systems that would require millions of test permutations for comprehensive coverage is an unsolved problem. In the paper, a general, robust, trustworthy, efficient, and comprehensive validation approach based on a Gaussian Process model (GP) of the test system has been developed that can operate system-agnostically, prevents calibration to a fixed set of known validation benchmarks, and supports large configuration spaces. The approach includes three steps that can be performed independently by different parties: 1) GP model creation, 2) model confirmation, and 3) model-based critical search for failures. The new approach has been applied to two systems utilizing different measurement methods for compliance testing of radiofrequency-emitting devices according to two independent standards, i.e., IEC 62209-1528 for scanning systems and IEC 62209-3 for array systems. The results demonstrate that the proposed measurement system validation is practical and feasible. It reduces the effort to a minimum such that it can be routinely performed by any test lab or other user and constitutes a pragmatic approach for establishing validity and effective equivalence of the two measurement device classes.

Published
2022

17. Determinants of mobile phone output power in a multinational study: implications for exposure assessment

Author

Vrijheid, M, Mann, S, Vecchia, P, Wiart, J, Taki, M, Ardoino, L, Armstrong, B K, Auvinen, A, Bédard, D, Berg-Beckhoff, G, Brown, J, Chetrit, A, Collatz-Christensen, H, Combalot, E, Cook, A, Deltour, I, Feychting, M, Giles, G G, Hepworth, S J, Hours, M, Iavarone, I, Johansen, C, Krewski, D, Kurttio, P, Lagorio, S, Lönn, S, McBride, M, Montestrucq, L, Parslow, R C, Sadetzki, S, Schüz, J, Tynes, T, Woodward, A, and Cardis, E

Published
2009

18. Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study

Author

Castano-Vinyals, G. Sadetzki, S. Vermeulen, R. Momoli, F. and Kundi, M. Merletti, F. Maslanyj, M. Calderon, C. and Wiart, J. Lee, A-K Taki, M. Sim, M. Armstrong, B. and Benke, G. Schattner, R. Hutter, H-P Krewski, D. Mohipp, C. Ritvo, P. Spinelli, J. Lacour, B. Remen, T. and Radon, K. Weinmann, T. Petridou, E. Th Moschovi, M. and Pourtsidis, A. Oikonomou, K. Kanavidis, P. Bouka, E. and Dikshit, R. Nagrani, R. Chetrit, A. Bruchim, R. Maule, M. Migliore, E. Filippini, G. Miligi, L. Mattioli, S. and Kojimahara, N. Yamaguchi, N. Ha, M. Choi, K. and Kromhout, H. Goedhart, G. `t Mannetje, A. Eng, A. and Langer, C. E. Alguacil, J. Aragones, N. and Morales-Suarez-Varela, M. Badia, F. Albert, A. Carretero, G. and Cardis, E. and Castano-Vinyals, G. Sadetzki, S. Vermeulen, R. Momoli, F. and Kundi, M. Merletti, F. Maslanyj, M. Calderon, C. and Wiart, J. Lee, A-K Taki, M. Sim, M. Armstrong, B. and Benke, G. Schattner, R. Hutter, H-P Krewski, D. Mohipp, C. Ritvo, P. Spinelli, J. Lacour, B. Remen, T. and Radon, K. Weinmann, T. Petridou, E. Th Moschovi, M. and Pourtsidis, A. Oikonomou, K. Kanavidis, P. Bouka, E. and Dikshit, R. Nagrani, R. Chetrit, A. Bruchim, R. Maule, M. Migliore, E. Filippini, G. Miligi, L. Mattioli, S. and Kojimahara, N. Yamaguchi, N. Ha, M. Choi, K. and Kromhout, H. Goedhart, G. `t Mannetje, A. Eng, A. and Langer, C. E. Alguacil, J. Aragones, N. and Morales-Suarez-Varela, M. Badia, F. Albert, A. Carretero, G. and Cardis, E.

Abstract

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We c

Published
2022

19. Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study

Author

Castaño-Vinyals, G, Sadetzki, S, Vermeulen, R, Momoli, F, Kundi, M, Merletti, F, Maslanyj, M, Calderon, C, Wiart, J, Lee, A-K, Taki, M, Sim, M, Armstrong, B, Benke, G, Schattner, R, Hutter, H-P, Krewski, D, Mohipp, C, Ritvo, P, Spinelli, J, Lacour, B, Remen, T, Radon, K, Weinmann, T, Petridou, E Th, Moschovi, M, Pourtsidis, A, Oikonomou, K, Kanavidis, P, Bouka, E, Dikshit, R, Nagrani, R, Chetrit, A, Bruchim, R, Maule, M, Migliore, E, Filippini, G, Miligi, L, Mattioli, S, Kojimahara, N, Yamaguchi, N, Ha, M, Choi, K, Kromhout, H, Goedhart, G, 't Mannetje, A, Eng, A, Langer, C E, Alguacil, J, Aragonés, N, Morales-Suárez-Varela, M, Badia, F, Albert, A, Carretero, G, Cardis, E, Castaño-Vinyals, G, Sadetzki, S, Vermeulen, R, Momoli, F, Kundi, M, Merletti, F, Maslanyj, M, Calderon, C, Wiart, J, Lee, A-K, Taki, M, Sim, M, Armstrong, B, Benke, G, Schattner, R, Hutter, H-P, Krewski, D, Mohipp, C, Ritvo, P, Spinelli, J, Lacour, B, Remen, T, Radon, K, Weinmann, T, Petridou, E Th, Moschovi, M, Pourtsidis, A, Oikonomou, K, Kanavidis, P, Bouka, E, Dikshit, R, Nagrani, R, Chetrit, A, Bruchim, R, Maule, M, Migliore, E, Filippini, G, Miligi, L, Mattioli, S, Kojimahara, N, Yamaguchi, N, Ha, M, Choi, K, Kromhout, H, Goedhart, G, 't Mannetje, A, Eng, A, Langer, C E, Alguacil, J, Aragonés, N, Morales-Suárez-Varela, M, Badia, F, Albert, A, Carretero, G, and Cardis, E

Abstract

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. W

Published
2022

20. Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study

Author

IRAS OH Epidemiology Chemical Agents, dIRAS RA-2, Castaño-Vinyals, G, Sadetzki, S, Vermeulen, R, Momoli, F, Kundi, M, Merletti, F, Maslanyj, M, Calderon, C, Wiart, J, Lee, A-K, Taki, M, Sim, M, Armstrong, B, Benke, G, Schattner, R, Hutter, H-P, Krewski, D, Mohipp, C, Ritvo, P, Spinelli, J, Lacour, B, Remen, T, Radon, K, Weinmann, T, Petridou, E Th, Moschovi, M, Pourtsidis, A, Oikonomou, K, Kanavidis, P, Bouka, E, Dikshit, R, Nagrani, R, Chetrit, A, Bruchim, R, Maule, M, Migliore, E, Filippini, G, Miligi, L, Mattioli, S, Kojimahara, N, Yamaguchi, N, Ha, M, Choi, K, Kromhout, H, Goedhart, G, 't Mannetje, A, Eng, A, Langer, C E, Alguacil, J, Aragonés, N, Morales-Suárez-Varela, M, Badia, F, Albert, A, Carretero, G, Cardis, E, IRAS OH Epidemiology Chemical Agents, dIRAS RA-2, Castaño-Vinyals, G, Sadetzki, S, Vermeulen, R, Momoli, F, Kundi, M, Merletti, F, Maslanyj, M, Calderon, C, Wiart, J, Lee, A-K, Taki, M, Sim, M, Armstrong, B, Benke, G, Schattner, R, Hutter, H-P, Krewski, D, Mohipp, C, Ritvo, P, Spinelli, J, Lacour, B, Remen, T, Radon, K, Weinmann, T, Petridou, E Th, Moschovi, M, Pourtsidis, A, Oikonomou, K, Kanavidis, P, Bouka, E, Dikshit, R, Nagrani, R, Chetrit, A, Bruchim, R, Maule, M, Migliore, E, Filippini, G, Miligi, L, Mattioli, S, Kojimahara, N, Yamaguchi, N, Ha, M, Choi, K, Kromhout, H, Goedhart, G, 't Mannetje, A, Eng, A, Langer, C E, Alguacil, J, Aragonés, N, Morales-Suárez-Varela, M, Badia, F, Albert, A, Carretero, G, and Cardis, E

Published
2022

22. EVALUATION OF SPECIFIC ABSORPTION RATE IN THE FAR-FIELD, NEAR-TO-FAR FIELD AND NEAR-FIELD REGIONS FOR INTEGRATIVE RADIOFREQUENCY EXPOSURE ASSESSMENT

Author

Liorni, I., Capstick, M., van Wel, L., Wiart, J., Joseph, W., Cardis, E., Guxens, M., Vermeulen, R., Thielens, A., One Health Chemisch, IRAS OH Epidemiology Chemical Agents, dIRAS RA-2, Child and Adolescent Psychiatry / Psychology, Laboratoire Traitement et Communication de l'Information (LTCI), Institut Mines-Télécom [Paris] (IMT)-Télécom Paris, Institut Polytechnique de Paris (IP Paris), Chaire Modélisation, Caractérisation et Maîtrise des expositions aux ondes électromagnétiques (C2M), Télécom ParisTech-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Département Communications & Electronique (COMELEC), Télécom ParisTech, One Health Chemisch, IRAS OH Epidemiology Chemical Agents, and dIRAS RA-2

Subjects
Electromagnetic field, Radio Waves, Near and far field, 010501 environmental sciences, 01 natural sciences, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Electromagnetic Fields, Wireless, Radiology, Nuclear Medicine and imaging, skin and connective tissue diseases, Absorption (electromagnetic radiation), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Exposure assessment, Remote sensing, Radiation, Radiological and Ultrasound Technology, business.industry, [SDE.IE]Environmental Sciences/Environmental Engineering, Public Health, Environmental and Occupational Health, Specific absorption rate, General Medicine, business, Whole body, Radio wave
Abstract

The specific absorption rate (SAR) induced by wireless radiofrequency (RF) systems depends on different parameters. Previously, SAR was mainly assessed under conditions of a single frequency and technology and for a limited number of localized RF sources. The current and emerging mobile systems involve a wider range of usage scenarios and are frequently used simultaneously, leading to combined exposures for which almost no exposure evaluation exists. The aim and novelty of this study is to close this gap of knowledge by developing new methods to rapidly evaluate the SAR induced by RF systems in such scenarios at frequencies from 50 MHz to 5.5 GHz. To this aim, analytical methods for SAR estimation in several usage scenarios were derived through a large-scale numerical study. These include subject-specific characteristics, properties of the RF systems and provide an estimation of the SAR in the whole body, tissues and organs, and different brain regions.

Published
2020
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27. Association between estimated whole-brain radiofrequency electromagnetic fields dose and cognitive function in preadolescents and adolescents

Author

Cabre-Riera, A, Wel, L, Liorni, I, Thielens, A, Birks, LE, Pierotti, L, Joseph, W, Gonzalez-Safont, L, Ibarluzea, J, Ferrero, A, Huss, A, Wiart, J, Santa-Marina, L, Torrent, M, Vrijkotte, T, Capstick, M, Vermeulen, R, Vrijheid, M, Cardis, E, Roosli, M, Guxens Junyent, Monica, Cabre-Riera, A, Wel, L, Liorni, I, Thielens, A, Birks, LE, Pierotti, L, Joseph, W, Gonzalez-Safont, L, Ibarluzea, J, Ferrero, A, Huss, A, Wiart, J, Santa-Marina, L, Torrent, M, Vrijkotte, T, Capstick, M, Vermeulen, R, Vrijheid, M, Cardis, E, Roosli, M, and Guxens Junyent, Monica

Abstract

Objective: To investigate the association between estimated whole-brain radiofrequency electromagnetic fields (RF-EMF) dose, using an improved integrated RF-EMF exposure model, and cognitive function in preadolescents and adolescents. Methods: Cross-sectional analysis in preadolescents aged 9–11 years and adolescents aged 17–18 years from the Dutch Amsterdam Born Children and their Development Study (n = 1664 preadolescents) and the Spanish INfancia y Medio Ambiente Project (n = 1288 preadolescents and n = 261 adolescents), two population-based birth cohort studies. Overall whole-brain RF-EMF doses (mJ/kg/day) were estimated for several RF-EMF sources together including mobile and Digital Enhanced Cordless Telecommunications phone calls (named phone calls), other mobile phone uses than calling, tablet use, laptop use (named screen activities), and far-field sources. We also estimated whole-brain RF-EMF doses in these three groups separately (i.e. phone calls, screen activities, and far-field) that lead to different patterns of RF-EMF exposure. We assessed non-verbal intelligence in the Dutch and Spanish preadolescents, information processing speed, attentional function, and cognitive flexibility in the Spanish preadolescents, and working memory and semantic fluency in the Spanish preadolescents and adolescents using validated neurocognitive tests. Results: Estimated overall whole-brain RF-EMF dose was 90.1 mJ/kg/day (interquartile range (IQR) 42.7; 164.0) in the Dutch and Spanish preadolescents and 105.1 mJ/kg/day (IQR 51.0; 295.7) in the Spanish adolescents. Higher overall estimated whole-brain RF-EMF doses from all RF-EMF sources together and from phone calls were associated with lower non-verbal intelligence score in the Dutch and Spanish preadolescents (−0.10 points, 95% CI -0.19; −0.02 per 100 mJ/kg/day increase in each exposure). However, none of the whole-brain RF-EMF doses was related to any other cognitive function outcome in the Spanish preadolescents o

Published
2021

28. Radiofrequency electromagnetic fields from mobile communication: Description of modeled dose in brain regions and the body in European children and adolescents.

Author

Birks, LE, Wel, L, Liorni, I, Pierotti, L, Guxens Junyent, Monica, Huss, A, Foerster, M, Capstick, M, Eeftens, M, El Marroun, Hanan, Estarlich, M, Gallastegi, M, Safont, LG, Joseph, W, Santa-Marina, L, Thielens, A, Torrent, M, Vrijkotte, T, Wiart, J, Röösli, M, Cardis, E, Vermeulen, R, Vrijheid, M, Birks, LE, Wel, L, Liorni, I, Pierotti, L, Guxens Junyent, Monica, Huss, A, Foerster, M, Capstick, M, Eeftens, M, El Marroun, Hanan, Estarlich, M, Gallastegi, M, Safont, LG, Joseph, W, Santa-Marina, L, Thielens, A, Torrent, M, Vrijkotte, T, Wiart, J, Röösli, M, Cardis, E, Vermeulen, R, and Vrijheid, M

Abstract

Background: Little is known about radiofrequency electromagnetic fields (RF) from mobile technology and resulting dose in young people. We describe modeled integrated RF dose in European children and adolescents combining own mobile device use and surrounding sources. Methods: Using an integrated RF model, we estimated the daily RF dose in the brain (whole-brain, cerebellum, frontal lobe, midbrain, occipital lobe, parietal lobe, temporal lobes) and the whole-body in 8358 children (ages 8–12) and adolescents (ages 14–18) from the Netherlands, Spain, and Switzerland during 2012–2016. The integrated model estimated RF dose from near-field sources (digital enhanced communication technology (DECT) phone, mobile phone, tablet, and laptop) and far-field sources (mobile phone base stations via 3D-radiowave modeling or RF measurements). Results: Adolescents were more frequent mobile phone users and experienced higher modeled RF doses in the whole-brain (median 330.4 mJ/kg/day) compared to children (median 81.8 mJ/kg/day). Children spent more time using tablets or laptops compared to adolescents, resulting in higher RF doses in the whole-body (median whole-body dose of 81.8 mJ/kg/day) compared to adolescents (41.9 mJ/kg/day). Among brain regions, temporal lobes received the highest RF dose (medians of 274.9 and 1786.5 mJ/kg/day in children and adolescents, respectively) followed by the frontal lobe. In most children and adolescents, calling on 2G networks was the main contributor to RF dose in the whole-brain (medians of 31.1 and 273.7 mJ/kg/day, respectively). Conclusion: This first large study of RF dose to the brain and body of children and adolescents shows that mobile phone calls on 2G networks are the main determinants of brain dose, especially in temporal and frontal lobes, whereas whole-body doses were mostly determined by tablet and laptop use. The modeling of RF doses provides valuable input to epidemiological research and to potential risk management regarding R

Published
2021

35. Pitfalls of toxicological investigations in hair, bones, and nails in extensively decomposed bodies: illustration with two cases

Author

Wiart, J-F. (Jean-Francois), Hakim, F. (Florian), Andry, A. (Aude), Eiden, C. (Celine), Drevin, G. (Guillaume), Lelievre, B. (Benedicte), Rouge-Maillart, C. (Clotilde), Decourcelle, M. (Marie), Lemaire-Hurtel, A-S. (Anne-Sophie), Allorge, D. (Delphine), Gaulier, J-M. (Jean-Michel), hakim fl, Toxicologie et Génopathies [CHRU Lille], Pôle de Biologie Pathologie Génétique [CHU Lille], Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille)-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), Groupe d'Étude des Interactions Hôte-Pathogène (GEIHP), Université d'Angers (UA), Centre Jean Bodin : Recherche Juridique et Politique (CJB), Impact de l'environnement chimique sur la santé humaine - ULR 4483 (IMPECS), Université de Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), CHU Lille, Institut Pasteur de Lille, Université de Lille, IMPact de l'Environnement Chimique sur la Santé humaine (IMPECS) - ULR 4483, Centre Hospitalier Régional Universitaire [Lille] [CHRU Lille], Impact de l'environnement chimique sur la santé humaine - ULR 4483 [IMPECS], Département de Pharmacologie-Toxicologie [CHU Angers], Centre Hospitalier Universitaire d'Angers [CHU Angers], and CHU Amiens-Picardie

Subjects
integumentary system, business.industry, [SDV]Life Sciences [q-bio], 010401 analytical chemistry, Postmortem period, Physiology, Lormetazepam, 01 natural sciences, 0104 chemical sciences, Pathology and Forensic Medicine, Time of death, Bone, Hair, Toxicology, Putrefaction, Nails, Forensic, 03 medical and health sciences, 0302 clinical medicine, Oxazepam, [SDV.TOX]Life Sciences [q-bio]/Toxicology, Medicine, 030216 legal & forensic medicine, business, ComputingMilieux_MISCELLANEOUS, medicine.drug
Abstract

It is difficult to carry out toxicological investigations in biological samples collected from extensively decomposed bodies and to interpret obtained results as several pitfalls should be considered: redistribution phenomena, degradation of xenobiotics during the postmortem period, contamination by putrefaction fluids, and external contamination. This work aims to present two cases in order to illustrate and discuss these difficulties in this tricky situation. Case#1: the body of a 30-year-old woman was found in a wooded area (1 month after she has been reported missing by her family): hair and a femur section were sampled. Case#2: the decomposed corpse of a 52-year-old man was found in a ditch: hair and nails were sampled. After decontamination steps, toxicological investigations were performed using liquid chromatography with high-resolution mass spectrometry and tandem mass spectrometry detection methods. In case#1, the same drugs or metabolites (benzodiazepines, propranolol, tramadol, acetaminophen, paroxetine, and oxetorone) were detected in hair and in bone specimens. This result combination strongly suggests intakes close to the time of death for three of them (oxazepam, lormetazepam, and propranolol). In case#2, results of toxicological investigations in hair and nails [(hair/nail concentration in ng/mg) nordiazepam (1.12/1.06), oxazepam (0.113/0.042), zolpidem (0.211/

Published
2020
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36. Estimated whole-brain and lobe-specific radiofrequency electromagnetic fields doses and brain volumes in preadolescents

Author

Cabré-Riera, A. (Alba), El Marroun, H. (Hanan), Muetzel, R.L. (Ryan), van Wel, L. (Luuk), Liorni, I. (Ilaria), Thielens, A. (Arno), Birks, L. (Laura), Pierotti, L. (Livia), Huss, A. (Anke), Joseph, W. (Wout), Wiart, J. (Joe), Capstick, M., Hillegers, M.H.J. (Manon), Vermeulen, R. (Roel), Cardis, E. (Elisabeth), Vrijheid, M. (Martine), White, T.J.H. (Tonya), Röösli, M. (Martin), Tiemeier, H.W. (Henning), Guxens Junyent, M. (Mònica), Cabré-Riera, A. (Alba), El Marroun, H. (Hanan), Muetzel, R.L. (Ryan), van Wel, L. (Luuk), Liorni, I. (Ilaria), Thielens, A. (Arno), Birks, L. (Laura), Pierotti, L. (Livia), Huss, A. (Anke), Joseph, W. (Wout), Wiart, J. (Joe), Capstick, M., Hillegers, M.H.J. (Manon), Vermeulen, R. (Roel), Cardis, E. (Elisabeth), Vrijheid, M. (Martine), White, T.J.H. (Tonya), Röösli, M. (Martin), Tiemeier, H.W. (Henning), and Guxens Junyent, M. (Mònica)

Abstract

Objective: To assess the association between estimated whole-brain and lobe-specific radiofrequency electromagnetic fields (RF-EMF) doses, using an improved integrated RF-EMF exposure model, and brain volumes in preadolescents at 9–12 years old. Methods: Cross-sectional analysis in preadolescents aged 9–12 years from the Generation R Study, a population-based birth cohort set up in Rotterdam, The Netherlands (n = 2592). An integrated exposure model was used to estimate whole-brain and lobe-specific RF-EMF doses (mJ/kg/day) from different RF-EMF sources including mobile and Digital Enhanced Cordless Telecommunications (DECT) phone calls, other mobile phone uses than calling, tablet use, laptop use, and far-field sources. Whole-brain and lobe-specific RF-EMF doses were estimated for all RF-EMF sources together (i.e. overall) and for three groups of RF-EMF sources that lead to a different pattern of RF-EMF exposure. Information on brain volumes was extracted from magnetic resonance imaging scans. Results: Estimated overall whole-brain RF-EMF dose was 84.3 mJ/kg/day. The highest overall lobe-specific dose was estimated in the temporal lobe (307.1 mJ/kg/day). Whole-brain and lobe-specific RF-EMF doses from all RF-EMF sources together, from mobile and DECT phone calls, and from far-field sources were not associated with global, cortical, or subcortical brain volumes. However, a higher whole-brain RF-EMF dose from mobile phone use for internet browsing, e-mailing, and text messaging, tablet use, and laptop use while wirelessly connected to the internet was associated with a smaller caudate volume. Conclusions: Our results suggest that estimated whole-br

Published
2020
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37. Evaluation of specific absorption rate in the far-field, near-to-far field and near-field regions for integrative radiofrequency exposure assessment

Author

One Health Chemisch, IRAS OH Epidemiology Chemical Agents, dIRAS RA-2, Liorni, I., Capstick, M., van Wel, L., Wiart, J., Joseph, W., Cardis, E., Guxens, M., Vermeulen, R., Thielens, A., One Health Chemisch, IRAS OH Epidemiology Chemical Agents, dIRAS RA-2, Liorni, I., Capstick, M., van Wel, L., Wiart, J., Joseph, W., Cardis, E., Guxens, M., Vermeulen, R., and Thielens, A.

Published
2020

40. Smurfs: Forensic aspects

Author

Gaulier, J.-M., primary, Salle, S., additional, Wiart, J.-F., additional, Richeval, C., additional, Humbert, L., additional, Tournel, G., additional, Beauval, N., additional, Bulai-Livideanu, C., additional, Legendre, L., additional, Payré, B., additional, Nisse, P., additional, and Allorge, D., additional

Published
2019
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41. Recall of mobile phone usage and laterality in young people: The multinational Mobi-Expo study

Author

Goedhart, G. van Wel, L. Langer, C.E. de Llobet Viladoms, P. Wiart, J. Hours, M. Kromhout, H. Benke, G. Bouka, E. Bruchim, R. Choi, K.-H. Eng, A. Ha, M. Huss, A. Kiyohara, K. Kojimahara, N. Krewski, D. Lacour, B. ‘t Mannetje, A. Maule, M. Migliore, E. Mohipp, C. Momoli, F. Petridou, E.T. Radon, K. Remen, T. Sadetzki, S. Sim, M. Weinmann, T. Cardis, E. Vrijheid, M. Vermeulen, R.

Abstract

Objective: To study recall of mobile phone usage, including laterality and hands-free use, in young people. Methods: Actual mobile phone use was recorded among volunteers aged between 10 and 24 years from 12 countries by the software application XMobiSense and was compared with self-reported mobile phone use at 6 and 18 months after using the application. The application recorded number and duration of voice calls, number of text messages, amount of data transfer, laterality (% of call time the phone was near the right or left side of the head, or neither), and hands-free usage. After data cleaning, 466 participants were available for the main analyses (recorded vs. self-reported phone use after 6 months). Results: Participants were on average 18.6 years old (IQR 15.2-21.8 years). The Spearman correlation coefficients between recorded and self-reported (after 6 months) number and duration of voice calls were 0.68 and 0.65, respectively. Number of calls was on average underestimated by the participants (adjusted geometric mean ratio (GMR) self-report/recorded = 0.52, 95% CI = 0.47-0.58), while duration of calls was overestimated (GMR=1.32, 95%, CI = 1.15-1.52). The ratios significantly differed by country, age, maternal educational level, and level of reported phone use, but not by time of the interview (6 vs. 18 months). Individuals who reported low mobile phone use underestimated their use, while individuals who reported the highest level of phone use were more likely to overestimate their use. Individuals who reported using the phone mainly on the right side of the head used it more on the right (71.1%) than the left (28.9%) side. Self-reported left side users, however, used the phone only slightly more on the left (53.3%) than the right (46.7%) side. Recorded percentage hands-free use (headset, speaker mode, Bluetooth) increased with increasing self-reported frequency of hands-free device usage. Frequent (≥50% of call time) reported headset or speaker mode use corresponded with 17.1% and 17.2% of total call time, respectively, that was recorded as hands-free use. Discussion: These results indicate that young people can recall phone use moderately well, with recall depending on the amount of phone use and participants’ characteristics. The obtained information can be used to calibrate self-reported mobile use to improve estimation of radiofrequency exposure from mobile phones. © 2018 Elsevier Inc.

Published
2018

42. Stochastic Dosimetry based on Low Rank Tensor Approximations for the Assessment of Children Exposure to WLAN Source

Author

Chiaramello E., Parazzini M., Fiocchi S., Ravazzani P., and Wiart J.

Subjects
Stochastic Dosimetry, Low RankTensor approximations, WLAN
Abstract

The exposure of a 8-years child to a 4G LTE femtocell, both (child and source) freely located in random positions in a realistic indoor environment was assessed by sparse low rank tensor approximation method (sparse LRA) for developing stochastic dosimetry by surrogate models. These latters were used for fast estimating the Specific Absorption Rate (SAR) in all the possible positions of femtocell and child and to assess the compliance with the International Commission of Non-Ionizing Radiation Protection (ICNIRP) guidelines for general public exposure. Results showed that, for all the possible positions in the room, the exposure values were significantly below the ICNIRP guidelines and that the probability of reaching SAR values higher than 1% of the ICNIRP guidelines value was lower than 0.006. The variation of the distance between femtocell and child influenced greatly the exposure, resulting in Quartile Coefficient of Dispersion values always higher than 48 %.

Published
2018

43. Children exposure to 4G LTE femtocell in indoor environments estimated by sparse low rank tensor approximations

Author

Chiaramello E, Parazzini M, Fiocchi S, Bonato M, Ravazzani P, and Wiart J

Subjects
Sparse low-rank approximation, Stochastic dosimetry, 4G LTE femtocell, RF-EMF exposure
Abstract

The exposure of an 8-year-old child to a femtocell operating at 2600 MHz, both (child and source) freely located in random positions in an indoor environment, was assessed. In order to develop surrogate models of the exposure, stochastic dosimetry based on sparse low-rank tensor approximation method (sparse LRA) was used. The surrogate models were used for fastly estimating the specific absorption rate (SAR) in all the possible positions of femtocell and child. Results showed that, for all the possible positions in the room, the exposure values were significantly below the International Commission of Non-Ionizing Radiation Protection (ICNIRP) guidelines for general public and that the probability of reaching SAR values higher than 1% of the ICNIRP guidelines value was lower than 0.006. The variation of the distance between femtocell and child influenced greatly the exposure, resulting in quartile coefficient of dispersion values always higher than 48%.

Published
2018
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