# Low-Frequency Magnetic Field Exposure System for Cells Electromagnetic Biocompatibility Studies
## 1 Introduction  
This article aims to design, develop, construct, and verify a new exposure system to study eukaryotic cells' low-frequency electromagnetic biocompatibility. The research on the electromagnetic field (EMF) effects on living cells in the low frequency (LF) and extremely low-frequency (ELF) range is a worldwide longtime discussed topic. Even though the thermal effects are relatively well understood nowadays, there are still more questions than answers around nonthermal impacts. An impressive amount of research works conducted within this area during the last few decades [1; 2; 3; 4; 5; 6] succeeded at least in terms of the necessity for nonthermal effects consideration when elucidating the response of the biological system to external EMF. In the LF range, the biological effects are usually investigated at weak levels, thus not likely to cause the thermal ones. One of the significant challenges in investigating the LF EMF nonthermal biological impacts is the lack of precise results in epidemiological and laboratory studies, pointing to a reliable mechanism of action between the LF EMF and living cells. The problem, whether electric field (EF) or the magnetic one (MF) is responsible for the biological effects of LF EMF in the nonthermal area, is not yet clarified. Still, some researchers point to the threshold foran external EF to elicit a biological effect at the cellular level around 10\({}^{-4}\) V\(\cdot\)m\({}^{-1}\)[7]. On the other hand, the safety action values for power frequency (50 Hz) EF irradiation of workers are [8] set between 1 and 2 \(\times\) 10\({}^{4}\) V\(\cdot\)m\({}^{-1}\). The same standard also defines action values for magnetic flux density specified for the frequency mentioned above in the range of 1-6 mT. The wide gap between the safety standards determined by policy documents and presented experimental results present sufficient space for research focused on nonthermal biological effects and possible health risks associated with long-term exposure to LF EMF. Several theories that describe the effects of weak LF MF on channel proteins in the cell membrane are discussed in scientific circles: the ion cyclotron resonance (ICR) theory, proposed by [PERSON] [9]; the ion parametric resonance (IPR) theory [10; 11]; the theory of free radical pairs [12; 13]. These three theories refer almost exclusively to the nonthermal action of the LF MF. New remarks and comments on these theories are constantly emerging. Despite decades of intensive work and expert discussions in this area, there is still no generally accepted theory for the action of LF EMF on cells. The biological effect of EMF depends on several field parameters such as intensity, range of frequencies used, duration of action as well as the properties of the organism, i.e., dimensions, weight, water content, state of the body, age and others; the possible adaptation and evolution cannot be forgotten in the long term [14]. The first published reports on the effects of EMF on biological objects come from 1971 [15] (there are 2311 references to studies that point to the biological effect of EMF, the oldest study from 1910 on the physiological effects of alternating magnetic field), 1975 [16] (selective calcium removal from cell membranes by EMF), and 1979 [17] (indicates the possible effect of the magnetic field generated by electrical lines on the incidence of children leukemia). Current research of potential associations between exposure to EMF and various health outcomes is mainly concerned with the study of the possible mechanisms of EMF action on biological structures, the impact of EMF on the efficacy of anticancer drugs [18; 19; 20] and the efficacy of calcium channels, the connection of EMF and childhood leukemia [21; 22], various types of malignancies, as well as the protective and therapeutic effects of EMF [23], drug and gene delivery [24]. The study is focused on the new exposure system for studying the LF MF nonthermal effects on cells.