Abstract. The study is focused on the analysis of total electron content (TEC) variations during six geomagnetic storms of different intensity: from Dstmin=-46 nT to Dstmin=-223 nT. The values of TEC deviations from its 27-day median value (δTEC) were calculated during the periods of the storms along three meridians: American, Euro-African and Asian-Australian. The following results were obtained. For the majority of the storms almost simultaneous occurrence of δTEC maximums was observed along all three meridians at the beginning of the storm. The transition from a weak storm to a superstorm (the increase of magnetic activity) almost does not affect the intensity of the δTEC maximum. The seasonal effect was most pronounced along the Asian-Australian meridian, less often along the Euro-African meridian and was not revealed along the American meridian. Sometimes the seasonal effect can penetrate to the opposite hemisphere. The character of average δTEC variations for the intense storms was confirmed by GOES satellite data. Though there are some common features of TEC variation revealed during each storm phase, in general no clear dependence of TEC responses on the storm phases was found: the effects were different during each storm at different locations. The behavior of the correlation coefficient (R) between δTEC values along the three meridians was analyzed for each storm. In general, R>0.5 between δTEC values averaged along each meridian. This result is new. The possible reasons for the exceptions (when R<0.5) were provided: the complexity of phenomena during the intense storms and discordance in local time of the geomagnetic storm beginning along different meridians. Notwithstanding the complex dependence of R on the intensity of magnetic disturbance, in general R decreased with the growth of storm intensity.

The concentration of N-nitrosamines (N-nitrosodimethylamine and N-nitrosodiethylamine) was measured in blood samples from children after consumption of drinking water with high content of nitrates (main group) or water meeting health standards (reference group). N-nitrosodimethylamine level in the blood from children of the main group differed from that in the reference group by 2.6 times (0.00026±0.00012 and 0.0001±0.00092 mg/dm, respectively; p<0.05). The specific immune response to N-nitrosodimethylamine exposure was manifested in an increase in the level of specific serum IgG (2 times higher than that in the reference group). An increase in the specific sensitivity to N-nitrosodimethylamine (by the criterion of IgG) was observed in 60.7% subjects. A correlation was found between an increase in the level of IgG to N-nitrosodimethylamine and rise in the concentration of N-nitrosodimethylamine in the blood (R =0.35; p=0.021). Under these conditions the spontaneous and induced production of arachidonic acid metabolites (leukotrienes) increased by 2.1 times, while the expression of p53 transcription factor (responsible for oncosuppression) decreased by 1.9 times as compared to those in the reference group (p<0.05).

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Introduction. Nowadays there is very relevant research on the study of the characteristics of the impact on the health of workers of low levels of harmful factors (acrylonitrile) of production during long-term exposure. Aim of the study was to examine peculiarities of immunologic and genetic indices in workers under the long-term exposure to acrylonitrile in low doses. Materials and methods. Our research object was working area air (MPCw.ar.=0.5 mg/m3) and biological media (blood and exhaled air) of workers employed at industrial rubber manufacture. Acrylonitrile was determined via a non-invasive procedure in exhaled air with samples being concentrated on sorption tubes that were then analyzed with capillary gas chromatography. Blood samples were examined to determine contents of malonic dialdehyde, lymphocytes (absolute and relative activated T-lymphocytes CD3+CD25+, absolute and relative activated T-lymphocytes CD3+CD95+), cytokines (VEGF), oncomarkers (PSA), and adrenals hormones; to do that, we applied ELISA tests and flow cytometry. Results. Acrylonitrile was established to occur in working area air in concentrations varying within MPCw.ar. range (0.007-0.015 mg/m3) being 2-3 times higher than in air inside offices at the same enterprise. We obtained statistically significant linear dependence between concentrations of acrylonitrile in the air exhaled by workers (y) and their working experience (x) that was given with the following equation: y=0.00046+0.00027x. According to the results of the laboratory examination of the workers, violations of the antioxidant defense were established. Contents of malonic dialdehyde and steroid hormones including progesterone, estradiol, and hydrocortisone that were pathogenetically linked to each other were authentically up to 3.2 times higher in the test group than in the reference one (p<0.05). Risk for antioxidant protection disorders such as elevated malonic dialdehyde contents in blood plasma might occur in the test group was 1.58 times higher than in the reference one. Conclusion. We revealed certain peculiarities in polymorphism of PPARGC1A Gly482Ser rs8192678 gene, the variability of which contributes to the formation of pathology of the cardiovascular, endocrine systems, oncoproliferative states that increase the likelihood of these undesirable events.

Introduction. Nowadays it has become especially vital to reveal basic regularities in workers’ health formation in order to provide early diagnostics and to reduce overall and occupational morbidity. The aim of the study was to examine polymorphism in ADD1 Gly460Trp rs4961 gene in workers exposed to chemical occupational factors at their workplaces (exemplified by saturated hydrocarbons). Materials and methods. We examined workplace air and biological media (urine and buccal epithelium) of exposed workers from the test group (n=162) and workers who didn’t deal with any technological processes at their workplaces (the reference group, n=83); both groups were employed at a potash flotation factory. To assess exposure to saturated hydrocarbons (hexane and heptane) in workplace air, we performed laboratory-instrumental tests of air inside workshops (11) and in administrative rooms with GANK-4 gas analyzer. Biological media (urine) were examined to determine contents of saturated hydrocarbons (hexane and heptane) in them by analyzing vapor phase in equilibrium on "Kristall-5000" gas chromatographer according to methodical Guidelines MUK 4.1.764-99. We analyzed polymorphism in ADD1 Gly460Trp rs4961 gene. Genetic typing was accomplished by polymerase chain reaction (PCR) in real time mode through allele discrimination with using TaqMan-probes on CFX96 (Bio-Rad) system as well as oligonucleotide primers and probes synthesized by "Sintol" company (Moscow). We applied Student’s t-test and Fischer’s Z-test to estimate authenticity of differences in obtained results. Pearson’s chi-square test (χ2) was used to check normalcy of quantitative data. We also assessed whether frequencies of candidate gene genotypes conformed to Hardy–Weinburg equilibrium. Results. Hexane was detected in workplace air in concentrations within 14–68 mg/m3 range (0.1MPCworkplace) during the observation period; heptane, 20–84 mg/m3 (0.1MPCworkplace). We assessed contamination of workers’ urine with hexane and heptane depending on their working experience that involved occupational contacts with saturated hydrocarbons, from 1 year and up to longer than 10 years. The assessment revealed that hexane contents were by 1.5 times higher and heptane contents by 1.22 times higher in workers with their working experience being longer than 10 years against workers with shorter working experience (less than 10 years). The results of a comparative analysis of the features of genetic polymorphism in the workers of the observation group in relation to the comparison group allowed us to establish significant differences between the frequencies of genotypes and alleles of the adducine gene ADD1 Gly460Trp rs4961, characterized by an increase in the frequency of the wild GG genotype of the gene. The assessment of the odds ratio (OR) of the presence in the observation group of the variation of the genotype GG of the gene ADD1 Gly460Trp rs4961 according to the multiplicative (for G allele inherited by dominant type OR=2.94; CI: 1.46–5.94; p<0.005) and general (for GG genotype, OR=3.14; CI: 1.44–6.86; p<0.005) inheritance models, as well as an assessment of the relative risk (for the G allele RR=1.38; CI: 1.23–1.53), allowed us to verify the reliable probability of the formation of genetically determined disorders associated with the development of arterial hypertension. Limitations. A limitation of the study is the study of the polymorphism of the ADD1 Gly460Trp rs4961 adducin gene only when exposed to two saturated hydrocarbons, hexane and heptane. Conclusion. Our research revealed that workers with basic production occupations and with working experience at the factory that was longer than 10 years had authentically higher hexane and heptane contents in their urine, by 1.5 (р<0.01) and 1.22 (р<0.048) times accordingly, than workers with their working experience at the factory being shorter than 10 years. We established that detection of hexane in concentrations equal to 0.006±0.002 mg/dm3 in urine of workers with basic production occupations who contacted saturated hydrocarbons vapors corresponded to 81% of the variation of the ADD1 Gly460Trp rs4961 gene in the form of a wild GG genotype (p<0.05) corresponded, which in conditions of contamination with marginal hydrocarbons can form the risk of cardiovascular pathology. Ethics. The research was performed in full conformity with ethical principles for medical research involving human subjects stipulated by the Declaration of Helsinki issued by the World Medical Association (the latest edition); all the participants gave their informed voluntary consent to take part in the research.