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Background: Free radicals are atoms, molecules or their fragments, whose excess leads to the development of oxidative stress, the cause of many neoplastic, neurodegenerative and inflammatory diseases, as well as aging of organisms. Industrial pollution, tobacco smoke, ionizing radiation, ultrasound and magnetic fields are the major exogenous sources of free radicals. The low frequency mag- netic field is commonly applied in physiotherapy. The aim of the present study was to evaluate the effect of extremely low frequency magnetic field (1L.F-MF) on the concentration ofsullhydryl groups (-SH) and proteins in liver tissues of experimental animals de- pending on the time of exposure to the field., Material and Methods: Twenty one Sprague-D)awley male rats, aged 3-4 months were randomly divided into 3 experimental groups (each containing 7 animals): controls (group I), the rats exposed to IEI.F-MF of 40 Hz, 7 mT (this kind of the ELF-MF is mostly used in magnetotherapy), 30 min/day for 2 weeks (group II) and the rats exposed to 40 Hz, 7 mT for 60 min/day for 2 weeks (group III). The concentrations of proteins and sulfhydryl groups in the liver tissues were determined after exposure to magnetic fields., Results: Exposure to low magnetic field: 40 Hz, 7 mT for 30 min/day and 60 min/day for 2 weeks caused a significant increase in the concentration of-SH groups and total protein levels in the liver tissues., Conclusions: The study results suggest that exposure to magnetic fields leads to the development of adaptive mechanisms to maintain the balance in the body oxidation-reduction and in the case of the studied parameters does not depend on the time of exposure.

Background: Nonylphenol (NP) has been found in daily used products reach in polyvinyl chloride (PVC). The main routes of human exposure are consumption of contaminated food and water. Radiation comes from natural and man-made sources, and is used in medicine, science and industry. Both agents are widely present in environment, therefore human exposure to their combined effect seems to be highly probable., Objective: The aim of the study was the estimation of the effects of subchronic exposure of male mice to nonylphenol alone and in a combination with ionizing radiation on the induction of DNA strand breaks of multiple somatic cells., Material and Method: Pzh:SFIS male mice were exposed for 8 weeks, 5 days/week to nonylphenol alone (25 mg/kg bw or 50 mg/kg bw ) or in a combination with X-rays (0.05 Gy + 25 mg/kg bw NP). Animal were killed at 24 h, 1,4 and 8 weeks after the end of exposure. The bone marrow, spleens, livers, kidneys and lungs were isolated from mice. The estimation of DNA damage was carried out by using Comet assay., Results: The most sensitive to nonylphenol occurred bone marrow lymphocytes, less sensitive were cells of spleen and lungs. NP did not induce the strand breaks in cells coming from liver and kidneys. Eight-weeks combined exposure to ionizing radiation and nonylphenol (0.05 Gy + 25 mg/kg bw NP) caused significantly enhanced level of DNA strand breaks in all tested cells. The most sensitive occurred bone marrow lymphocytes and spleen cells, whereas cells from kidneys and lungs were the least sensitive., Conclusion: Subchronic application ofnonylphenol to mice induced damage to genetic material of bone marrow lymphocytes and cells of spleen and lungs. Combined exposure to ionizing radiation and nonylphenol caused, significantly higher than NP alone, level of DNA strand breaks of bone marrow lymphocytes, cells of liver, spleen, lungs and kidneys. Such damages might be stimulated by ionizing radiation.

The aim of study was to estimate the effects of bisphenol A (BPA) and combined exposure to X-rays and BPA to somatic cells of the bone marrow and liver of mice. Male mice Pzh: Sfis were irradiated with 0.05 Gy or treated with BPA (5 mg/kg mc, 10 mg/kg mc, 20 mg/kg mc) or exposed to a combination of both (0.05 Gy + 5 mg/kg BPA) for 8 weeks. Samples were taken at 24h, 1, 4 and 8 weeks after the end of exposure. Our study showed, that BPA can induce, measured by Comet assay, DNA damage in limphocytes of the bone marrow. The induction of DNA damage in somatic cells of the liver was not detected. After combined exposure to both agents a greater migration of DNA in cells of both organs than after the exposure to bisphenol A alone was observed. Probably the X-rays intensify the genotoxicity of BPA.

Since the mid 1970's, when Adey discovered that extremely-low-frequency electromagnetic field (ELF EMF) may affect the calcium ions efflux from various cells, bioeffects of non-ionizing radiation (NIR) have become the subject of growing interest and numerous research projects. At present, the fact that NIR exerts both stimulatory and inhibitory effects on different physiological cellular parameters is rather unquestionable. At the same time, some epidemiological studies suggest that exposure to EMF is potentially harmful even if its intensity is very low. It has been proved that thermal factors are not responsible for these effects, therefore nowadays, they are called 'non-thermal effects'. Our paper deals with three different aspects of biological effects of non-ionizing radiation, bioelectromagnetism, electromagnetobiology and electromagnetic bioinformation. Firstly, we describe how EMF and photons can be produced within a living cell, how biological cycles are controlled, and what are the features of endogenous electromagnetic radiation. Secondly, we discuss various facets of external EMF interactions with living matter, focusing on extremely-low-frequencies, radio- and microwaves. Possible mechanisms of these interactions are also mentioned. Finally, we present a short overview of current theories which explain how electromagnetic couplings may control an open and dissipative structure, namely the living organism. The theory of electromagnetic bioinformation seems to explain how different physiological processes are triggered and controlled, as well as how long-range interactions may possibly occur within the complex biological system. The review points out that the presented research data must be assessed very carefully since its evaluation is crucial to set the proper limits of EMF exposure, both occupational and environmental. The study of biological effects of non-ioinizing radiation may also contribute to the development of new diagnostic and therapeutic methods.

The experiment was carried out on 40 rabbits divided in four groups. Each animal of the experimental groups received a 850 R dose. X-rays were applied for irradiation. The animals were sacrificed on the 7th, 12th and 17th day after irradiation. Levels of ATP/ADP and phosphocreatine were determined in the skeletal muscles, myocardium, liver, kidneys, blood and the mucosa of duodenum. On the 7th day, in all tissues a decrease of the phosphocreatine level was observed. The lowest level differed little from zero. Afterwards a slow increase of phosphocreatine concentration took place, reaching the normal level in the kidneys on the 17th day after irradiation. The concentration of ATP/ADP was the lowest on the 7th day of the experiment. A fast increase of that fraction was observed in the liver, where the level of ATP/ ADP on the 12th day was higher than in the control group. From the 12th day, a drop in the ATP/ADP level was observed, reaching the normal level on the 17th day. In the skeletal and heart muscles, after a drop on the 7th day, a slow increase of the activity was observed on the last day of the experiment, but the activity did not reach the normal level.

Two groups of experimental animals, each consisting of 12 rabbits, were subjected to local fractional irradiation with cobalt 60. Group I received the total dose of 2580 R during 13 days, group II - 5100 R during 24 days. The effects of irradiation were estimated on the strength of histological examination of the liver immediately and after 7, 15, 30, 60 and 90 days after the last exposition. The histological sections were stained with haematoxylin and eosin, and colour reactions were performed for argentaffine and collagen fibres and for glycogen, neutral fats, alkaline and acid phosphatase, ATP-ase, glycose-6-phosphatase, non-specific esterase and succinic acid dehydrogenase. It was found that the dose of 2580 R is safe for the liver. The effects of irradiation were slight and limited to weak catabolic disturbances in the form of mild steatosis of the liver and of a transient and short-lived fall of glycogen and rise of hydrolytic enzymes. More pronounced and intense changes were observed in the other group of animals. During the early period, the changes were of a retrograde character and were typical of the acute post-irradiation effect. There was necrosis of the walls of the blood vessels, of the epithelium of the bile ducts and of the liver cells, accompanied by a rise in the hydrolytic enzymes and by a considerable fall of the level of glycogen and succinic acid dehydrogenase. During the late period (30-90 days), changes typical of the so-called post-irradiation hepatitis were found histologically.

Twenty four rabbits were used in the experiment. The animals were divided into four groups, 6 animals in each. The rabbits were irradiated with a total dose of 910 R. The activity of alkaline phosphatase and the level of inorganic phosphorus were measured on the 5th, 10th and 15th day after irradiation in erythrocytes, plasma, duodenum, muscles and liver. There was found a decrease of phosphatase activity in the plasma, liver and duodenum, and an increase in the muscles and erythrocytes. The level of inorganic phosphorus increased in the duodenum, liver and plasma, and decreased in the muscles and erythrocytes. In the latter two, the increase of the phosphatase activity was accompanied by a decrease of the phosphorus level; on the contrary, the decrease of the enzyme activity in the liver and duodenum was accompanied by an increase of the phosphorus level. During the whole experimental period, the phosphatase activity was higher by about 40% than in the control group.

The 50 Hz frequency electric field was applied to guinea pigs at different times of the day. The effects of electric field upon RNA and soluble proteins level in nuclear, mitochondrial and supernatant guinea pigs liver were tested. An increase in RNA and soluble proteins content in all the test fractions was found, as dependent on the time of stimulus application.

50 Hz high tension (HT) electric field is not indifferent to the health of human beings and living organisms within the range of its effects. The electric field effects may be illustrated by man's EEG and blood changes, plants cellular structure, or an increase in animals' body weight and some organs. The work has been aimed at demonstrating that the electric field of 100 kV/m intensity and 50 Hz frequency affects selected biochemical parameters of guinea pigs' liver. The experiments have shown statistical changes in nucleic acid soluble proteins and alanine and asparagine aminotransferases.