RESUMO
Workers inside transmission pylons with FM antenna arrays are likely to be exposed to near-field radiation exceeding reference levels for occupational exposure. In this study, the near-field behavior of 64 FM pylons was studied using a new methodology. Near-field characterization was done using field metrics without taking into account field sources' size or distance from field source. The specific absorption rate (SAR) was assessed in five hundred different near-field cases using a human phantom. Estimation formulas for both local and whole-body SAR are provided and validated numerically. Local and whole-body SAR are linked to electric field strength. © 2022 Bioelectromagnetics Society.
Assuntos
Campos Eletromagnéticos , Exposição Ocupacional , Campos Eletromagnéticos/efeitos adversos , Humanos , Exposição Ocupacional/efeitos adversos , Imagens de Fantasmas , Doses de RadiaçãoRESUMO
Nowadays, information and communication technologies (mobile phones, connected objects) strongly occupy our daily life. The increasing use of these technologies and the complexity of network infrastructures raise issues about radiofrequency electromagnetic fields (Rf-Emf) exposure. Most previous studies have assessed individual exposure to Rf-Emf, and the next level is to assess populational exposure. In our study, we designed a statistical tool for Rf-Emf populational exposure assessment and mapping. This tool integrates geographic databases and surrogate models to characterize spatiotemporal exposure from outdoor sources, indoor sources, and mobile phones. A case study was conducted on a 100 × 100 m grid covering the 14th district of Paris to illustrate the functionalities of the tool. Whole-body specific absorption rate (SAR) values are 2.7 times higher than those for the whole brain. The mapping of whole-body and whole-brain SAR values shows a dichotomy between built-up and non-built-up areas, with the former displaying higher values. Maximum SAR values do not exceed 3.5 and 3.9 mW/kg for the whole body and the whole brain, respectively, thus they are significantly below International Commission on Non-Ionizing Radiation Protection (ICNIRP) recommendations. Indoor sources are the main contributor to populational exposure, followed by outdoor sources and mobile phones, which generally represents less than 1% of total exposure.
Assuntos
Telefone Celular , Comunicação , Campos Eletromagnéticos , Exposição Ambiental , Campos Eletromagnéticos/efeitos adversos , Humanos , Ondas de Rádio/efeitos adversosRESUMO
The spatial structure of the vertical component of the electric field emitted by base stations in the Brussels region (Belgium) is measured, and studied using the variogram. A relationship between the variogram shape and base station antenna density in each measurement area is found; the variogram range and sill level are shown to depend on cellular base stations' antenna density, following exponential laws. Bioelectromagnetics. 37:557-562, 2016. © 2016 Wiley Periodicals, Inc.
RESUMO
We used the ant species Myrmica sabuleti as a model to study the impact of electromagnetic waves on social insects' response to their pheromones and their food collection. We quantified M. sabuleti workers' response to their trail, area marking and alarm pheromone under normal conditions. Then, we quantified the same responses while under the influence of electromagnetic waves. Under such an influence, ants followed trails for only short distances, no longer arrived at marked areas and no longer orientated themselves to a source of alarm pheromone. Also when exposed to electromagnetic waves, ants became unable to return to their nest and recruit congeners; therefore, the number of ants collecting food increases only slightly and slowly. After 180 h of exposure, their colonies deteriorated. Electromagnetic radiation obviously affects social insects' behavior and physiology.
Assuntos
Comportamento Animal/efeitos dos fármacos , Comportamento Animal/efeitos da radiação , Radiação Eletromagnética , Feromônios/farmacologia , Animais , FormigasRESUMO
The kinetics of the acquisition and loss of the use of olfactory and visual cues were previously obtained in six experimental colonies of the ant Myrmica sabuleti meinert 1861, under normal conditions. In the present work, the same experiments were conducted on six other naive identical colonies of M. sabuleti, under electromagnetic radiation similar to those surrounding GSM and communication masts. In this situation, no association between food and either olfactory or visual cues occurred. After a recovery period, the ants were able to make such an association but never reached the expected score. Such ants having acquired a weaker olfactory or visual score and still undergoing olfactory or visual training were again submitted to electromagnetic waves. Not only did they lose all that they had memorized, but also they lost it in a few hours instead of in a few days (as under normal conditions when no longer trained). They kept no visual memory at all (instead of keeping 10% of it as they normally do). The impact of GSM 900 MHz radiation was greater on the visual memory than on the olfactory one. These communication waves may have such a disastrous impact on a wide range of insects using olfactory and/or visual memory, i.e., on bees.