Vol 28, No 6 (2021)

Background: Liquid and solid fuels are the main source of lead (Pb) in urban settings. Some household items have also been identified as sources of lead. Thus, monitoring of this trace element in humans remains an important public health issue. Aim: To assess concentration of lead in hair of residents of Gorno-Altaisk city - the administrative center of the Altai Republic and to estimate the proportion of the population with high hair concentration of lead. Methods: Hair samples were collected from 122 (50.8 % men) neither smoking nor taking mineral supplements healthy permanent residents of Gorno-Altaisk aged 4-50 years. Fifty-three percent of them lived in the central part of the city. Concentration of led in the hair samples was estimated by atomic absorption method. Differences in average concentrations across genders, age-groups and locations were studied using Mann - Whitney tests. Associations between continuous variables were studied by non-parametric correlation analysis. Results: The average lead hair concentration in Gorno-Altaisk was 3.18 mg/kg which exceeds the values previously reported from other Russian settings (0.5-3.0 mg/kg). Twenty-six percent of residents had hair concentration of lead above the maximum allowed level of 5.0 mg/kg. Hair lead concentration positively correlated with age (r = 0.54), but was not associated with either gender or place of residence. Conclusions: Average concentration of led in human hair in Gorno-Altaisk is high, but it does not exceed the maximum allowed level. More than every fourth resident of the city has hair lead concentration exceeding biologically acceptable level. We found significant associations between hair lead concentrations and age, but not with gender or place of residence.

Aim: To study electroencephalographic (EEG) changes in adolescents with different risks of developing Internet addiction (IA). Methods: This cross-sectional study included 1б-17 years-old adolescents (n = 55) permanently living in the Arctic Russian town of Arkhangelsk. Risk of IA was assessed using the Chen Internet Addiction Scale (CIAS). By the results of the CIAS test all adolescents were divided into three groups: I - minimal risk of IA, II - increased risk to develop IA and III - stable IA pattern. EEG was evaluated by the values of spectral power (|jV2) in each frequency band. Results: Altogether, 25.5 % of adolescents had minimal risk of developing IA, б3.б% belonged to group 2 and 10.9 % had IA. The organized type of alpha activity EEG was found in 79 % of individuals in group I and in 100 % of individuals in group III. This indicates the optimal age ratio of the activity of the reticular formation, cerebral cortex and diencephalic structures. A large number of negative correlations between compulsive symptoms of IA and all types of EEG activity in group I was determined, which may indicate a resistance of these individuals to addiction. The organized EEG type was detected in 54 %, hypersynchronous type - in 14 %, desynchronized type - in 14 %, disorganized type - in 18 % of group II individuals. A disorganized EEG type with a large ratio of theta EEG waves in the frontal-central brain parts in group II may indicate a high limbic-diencephalic excitation. The correlations between the indicators of the withdrawal symptom scale and the EEG theta-activity reflect the psychological discomfort when access to Internet resources is difficult. Conclusions: Most adolescents with minimal risk of IA and symptoms IA have an organized EEG-type while adolescents with IA have this EEG-type only in a half of the cases, which is caused by the heterochronia of the EEG formation in the Arctic residents and the peculiarities of the formation and development of IA.

Aim: To study associations between selected weather factors on the number of ambulance calls for selected respiratory diseases in the city of Petrozavodsk, Northwest Russia. Methods: Data on the number of ambulance calls in the city of Petrozavodsk were obtained for the period from 2015-2017. Associations between weather factors and the number of ambulance calls for respiratory diseases were studied by correlation analysis. Pearson's correlation coefficients were calculated. Separate analyses were performed for acute upper respiratory tract infections (J06), viral pneumonia (J12), acute bronchitis (J20) and asthma (J45). An additional analysis was performed for the warm- (14 months with the mean monthly temperature from +9.8 to +18.4 °C) and the cold (22 months with a temperature from -14.9 to +5.0 °C) seasons. Results: The overall number of ambulate calls for viral pneumonia decreased during the study period. Significant associations between air temperature and atmospheric pressure and the number of calls for respiratory deceases, particularly for acute respiratory tract infections. During the cold season the influence of the temperature factor on the number of calls decreased for the most cases except acute bronchitis. The lowest number of calls for acute bronchitis was observed during summers. In summer, the number of calls for acute bronchitis was positively associated with wind speed and inversely associated with mean temperature and humidity. The number of calls for acute respiratory infections was positively associated with intraday increase in barometric pressure and wind speed. In autumn, significant correlations were observed between the North-West wind, which carries air pollutants from the industrial part of the city to the residential area and the number ambulance calls. In winter, an inverse association between humidity and ambulance calls for viral pneumonia was found. In spring, significant associations between the number of ambulance calls for several respiratory causes and cloudiness were observed. Conclusion: Significant associations between weather factors and the number of ambulance calls for respiratory causes were observed in the city of Petrozavodsk. Our results can contribute to better planning of ambulance services in town.

Introduction: Tobacco smoking and hazardous alcohol consumption significantly contribute to the burden of diseases worldwide. Characteristics of the environment has been consistently shown to be associated with the patterns of tobacco smoking and alcohol consumption patterns. This evidence has been previously summarized on country- and neighbourhood-level reviews although the evidence on the associations on the regional level is still scarce. Aim: to present a protocol of the systematic review of available evidence on the associations between certain characteristics of large national regions and alcohol consumption and tobacco smoking. Methods: A systematic search of PubMed, Google Scholar, OpenGrey, CrossRef, and eLibrary) will be conducted to identify original studies with no date or language restrictions. Only studies with territorial characteristics as exposure variables and with tobacco smoking and alcohol consumption as the outcomes will be selected. The studies have no restrictions regarding participant characteristics, that is, gender, age, socioeconomic criteria, or health status. Titles, abstracts, and full text of articles retrieved from the search will be screened and read independently by two reviewers for eligibility. Articles selected for inclusion will be critically and independently appraised by two reviewers. The full-text of the selected studies will be assessed in detail, and findings and their illustrations will be extracted and aggregated. Any disagreements between the reviewers that may arise at any stage will be resolved through discussion, or mediated by a third reviewer. Systematic review registration number: PROSPEROCRD42021234874.