Two-day-old honeybee workers (± 6 h) were placed in cages and supplied with sucrose solution (1 mol/dm3) ad libitum. Subsequently, the cages with bees were placed in an electric field (E-field) exposure system with field intensities of 5.0 kV/m, 11.5 kV/m, 23 kV/m, and 34.5 kV/m. The duration of exposure was 1 h, 3 h, and 6 h. The biochemical parameters SOD (superoxide dismutase), CAT (catalase), FRAP (ferric ion reducing antioxidant power), and also acidic, neutral, and alkaline proteases in the worker bee hemolymph were analyzed. The E-field increased activities of antioxidant systems, especially SOD, and also the proteolytic systems. In the groups: 11.5 kV/m–time 6 h, 23.0 kV/m–time 1 h, and 34.5 kV/m–time 1 h, FRAP levels were decreased in comparison with the control samples. These findings are discussed in context with possible consequences for honeybee health in urban and rural environments.

EM-fields come from both natural and anthropogenic sources. This study aimed to investigate changes in honeybee behavior parameters under the influence of an electric field at 50 Hz and variable intensity. Bees were exposed for 1 h, 3 h, or 6 h to the following artificial E-field intensities: 5.0 kV/m, 11.5 kV/m, 23.0 kV/m, or 34.5 kV/m. Bees in the control group were under the influence of an E-field <2.0 kV/m. Six basic behaviors were selected for bee observation (walking, grooming, flight, stillness, contact between individuals, and wing movement). Our research shows the impact of bee exposure time on behavioral change within groups. Exposure for 3 h caused a decrease in the time that bees spent on behaviors and in the number of occurrences. After 6 h, the parameters increased within the groups, as was the case with 1 h exposure. This may indicate that there is a behavioral barrier that allows the pattern to normalize for some time.

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In recent years, on a global scale, more and more reports of a phenomenon called CCD (Colony Collapse Disorder) have been reported. In addition to pesticides, diseases, and other environmental stressors, electromagnetic fields are also mentioned as one of the possible causes of CCD. One of the body’s first lines of defense against harmful factors is the antioxidant system. We hypothesized that electromagnetic field upregulate the activity of SOD (superoxide dismutase), CAT (catalases), and changed FRAP (total antioxidant potential) in honeybee hemolymph. In our research, 12 h bee’s exposure to E-field was analyzed to determine changes in the antioxidant system. The frequency of 50 Hz and various intensities were used: 5.0 kV/m, 11.5 kV/m, 23.0 kV/m, and 34.5 kV/m. Superoxide dismutase was characterized by four times higher activity in the study groups as compared to the control group. Catalase activity in all groups was characterized by statistically significantly different activity between the groups. The highest activity was recorded in the 34.5 kV/m group. The lowest activity was recorded in the 11.5 kV/m group. A relationship was found between different E-field intensities and changes in the antioxidant system.

The effect of an artificial electromagnetic field on organisms is a subject of extensive public debate and growing numbers of studies. Our study aimed to show the effect of an electromagnetic field at 50 Hz and variable intensities on honey bee proteolytic systems and behavior parameters after 12 h of exposure. Newly emerged worker bees were put into cages and exposed to a 50 Hz E-field with an intensity of 5.0 kV/m, 11.5 kV/m, 23.0 kV/m, or 34.5 kV/m. After 12 h of exposure, hemolymph samples were taken for protease analysis, and the bees were recorded for behavioral analysis. Six behaviors were chosen for observation: walking, flying, self-grooming, contact between individuals, stillness, and wing movement. Bees in the control group demonstrated the highest number of all behavior occurrences, except flying, and had the lowest protease activity. Bees in the experimental groups showed a lower number of occurrences of walking, self-grooming, and contacts between individuals than the control bees and had significantly higher protease activity than the control bees (except that of alkaline proteases in the 23.0 kV/m group).

StreszczenieWstęp: Badania nad oddziaływaniem pola elektromagnetycznego na organizmy żywe są istotnym elementem badań biofizycznych. Są to badania interdyscyplinarne, łączące nierozerwalnie biologię i medycynę z techniką wytwarzania i pomiaru pól elektromagnetycznych. Celem pracy jest analiza układów ekspozycyjnych pola magnetycznego ekstremalnie niskich częstotliwości w badaniach biomedycznych oraz metod pomiarów parametrów pola. Materiał i metody: Badaniom poddano 2 najpopularniejsze układy ekspozycyjne pola magnetycznego niskiej częstotliwości -solenoid i cewki Helmholtza. Przeprowadzono analizy teoretyczne i weryfikację pomiarową rozkładu pola w układach w celu oceny jednorodności pola. Zbadano również czynniki dodatkowe wpływające na ocenę biologicznych efektów ekspozycji -drgania i zmiany temperatury. Wyniki: Na podstawie przeprowadzonych badań przedstawiono analizę porównawczą solenoidów i cewek Helmholtza jako układów ekspozycyjnych pola magnetycznego oraz sformułowano wnioski dotyczące opisu warunków ekspozycji na pole magnetyczne. Wnioski: Autorzy podkreślają znaczenie świadomego doboru warunków ekspozycji i ich jednoznacznego opisu. Jest to podstawą odtworzenia warunków doświadczalnych oraz weryfikacji uzyskanych wyników. Med. Pr. 2015;66(2):185-197 Słowa kluczowe: pole elektromagnetyczne, układ ekspozycyjny, metrologia pola elektromagnetycznego, solenoid, cewki Helmholtza, bioelektromagnetyzm Abstract Background: Experiments on the electromagnetic field influence on organisms are an important part of biophysical studies. It is an interdisciplinary research spanning biology and medicine with the engineering in generation and measurement of electromagnetic fields. The aim of the study consists in the analysis of parameters estimations and measurements of extremely low frequency magnetic field (ELF MF) as well as exposure systems parameters in biomedical research. Material and Methods: Experiments were performed on 2 most popular low magnetic field exposure systems: the solenoid and Helmholtz coils. A theoretical analysis and a measurement verification of the magnetic field distribution inside the systems were carried out to evaluate the homogeneity of the magnetic field. Additional factors, vibrations and temperature changes, affecting the assessment of the biological effects of magnetic field exposure were also examined. Results: Based on the study results, a comparative analysis of solenoids and Helmholtz coils as the magnetic field exposure systems was presented. Proposals for the description of magnetic field exposure were also formulated. Conclusions: The authors emphasize the importance of a conscious choice of exposure conditions and their explicit description. These are fundamental requirements for both the reproduction of experimental conditions and the verification of results. Med Pr 2015;66(2): [185][186][187][188][189][190][191][192][193][194][195][196][197]

No abstract

Background: Presented information about the welding process and equipment, focusing on the emission of electromagnetic field (EMF) with levels significant in terms of the labor safety regulations in force in Poland -the ordinances of the Minister of Family, Labour and Social Policy that came into force on June 27, 2016 and June 29, 2016 -emerged due to harmonization with European Union directive 2013/35/EU of 26 June 2013 of the European Parliament and the Council. They presented methods of determination of the EMF distribution in the welding machine surroundings and analyzed the background knowledge from the available literature. Material and Methods: The subject of the analysis included popular high frequency welders widely used in the industry. Electromagnetic field measurements were performed in the welder operating place (in situ) during machine normal operations, using measurement methods accordant with labor safety regulations in force in Poland and according to the same guidelines, the EMF distributions and parameters having been described. Results: They presented various scenarios of particular, real examples of excessive exposure to EMF in the dielectric welder surroundings and showed solutions, ranging from simple and costless and ending on dedicated electromagnetic shielding systems, which allowed to reduce EMF exposure in some cases of more than 80% (protection zone ranges) or eliminate dangerous zone presence. Conclusions: It has shown that in the dielectric welders surrounding, significant EMF strength levels may be the result of errors or omissions which often occur during development, installation, operation or modification of welding machines. It has allowed to present the measures that may significantly reduce the exposure to EMF of workers in the welder surroundings. The role of accredited laboratories in helping in such cases was underlined. Med Pr 2017;68(6):693-703