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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Ekologiya cheloveka (Human Ecology)</journal-id><journal-title-group><journal-title xml:lang="en">Ekologiya cheloveka (Human Ecology)</journal-title><trans-title-group xml:lang="ru"><trans-title>Экология человека</trans-title></trans-title-group></journal-title-group><issn publication-format="print">1728-0869</issn><issn publication-format="electronic">2949-1444</issn><publisher><publisher-name xml:lang="en">Eco-Vector</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">633016</article-id><article-id pub-id-type="doi">10.17816/humeco633016</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>ORIGINAL STUDY ARTICLES</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ ИССЛЕДОВАНИЯ</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Mineral composition and type of saliva microcrystallization in residents of major industrial regions</article-title><trans-title-group xml:lang="ru"><trans-title>Минеральный состав и тип микрокристаллизации слюны у жителей крупных промышленных регионов</trans-title></trans-title-group><trans-title-group xml:lang="zh"><trans-title>大型工业地区居民的唾液矿物成分与微结晶类型</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4918-6937</contrib-id><contrib-id contrib-id-type="spin">9161-0264</contrib-id><name-alternatives><name xml:lang="en"><surname>Sarf</surname><given-names>Elena A.</given-names></name><name xml:lang="ru"><surname>Сарф</surname><given-names>Елена Александровна</given-names></name><name xml:lang="zh"><surname>Sarf</surname><given-names>Elena A.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><email>sarf_ea@omgpu.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5503-4898</contrib-id><contrib-id contrib-id-type="spin">7940-6589</contrib-id><name-alternatives><name xml:lang="en"><surname>Stepanova</surname><given-names>Lyudmila V.</given-names></name><name xml:lang="ru"><surname>Степанова</surname><given-names>Людмила Васильевна</given-names></name><name xml:lang="zh"><surname>Stepanova</surname><given-names>Lyudmila V.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Assistant Professor</p></bio><bio xml:lang="ru"><p>доцент</p></bio><bio xml:lang="zh"><p>Assistant Professor</p></bio><email>slyudmila@mail.ru</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9552-447X</contrib-id><contrib-id contrib-id-type="spin">8008-5580</contrib-id><name-alternatives><name xml:lang="en"><surname>Kolenchukova</surname><given-names>Oksana A.</given-names></name><name xml:lang="ru"><surname>Коленчукова</surname><given-names>Оксана Александровна</given-names></name><name xml:lang="zh"><surname>Kolenchukova</surname><given-names>Oksana A.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Dr. Sci. (Biology), Assistant Professor</p></bio><bio xml:lang="ru"><p>д-р биол. наук, доцент</p></bio><bio xml:lang="zh"><p>Dr. Sci. (Biology), Assistant Professor</p></bio><email>Kalina-chyikova@mail.ru</email><xref ref-type="aff" rid="aff2"/><xref ref-type="aff" rid="aff3"/><xref ref-type="aff" rid="aff4"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-6147-4854</contrib-id><contrib-id contrib-id-type="spin">4189-7899</contrib-id><name-alternatives><name xml:lang="en"><surname>Bel'skaya</surname><given-names>Lyudmila V.</given-names></name><name xml:lang="ru"><surname>Бельская</surname><given-names>Людмила Владимировна</given-names></name><name xml:lang="zh"><surname>Bel'skaya</surname><given-names>Lyudmila V.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Cand. Sci. (Chemistry)</p></bio><bio xml:lang="ru"><p>канд. хим. наук</p></bio><bio xml:lang="zh"><p>Cand. Sci. (Chemistry)</p></bio><email>belskaya@omgpu.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Omsk State Pedagogical University</institution></aff><aff><institution xml:lang="ru">Омский государственный педагогический университет</institution></aff><aff><institution xml:lang="zh">Omsk State Pedagogical University</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Siberian Federal University</institution></aff><aff><institution xml:lang="ru">Сибирский федеральный университет</institution></aff><aff><institution xml:lang="zh">Siberian Federal University</institution></aff></aff-alternatives><aff-alternatives id="aff3"><aff><institution xml:lang="en">Scientific Research Institute of Medical Problems of the North of the Krasnoyarsk Scientific Center of the Siberian Branch of the Russian Academy of Sciences</institution></aff><aff><institution xml:lang="ru">Научно-исследовательский институт медицинских проблем Севера Красноярского научного центра Сибирского отделения Российской академии наук</institution></aff><aff><institution xml:lang="zh">Scientific Research Institute of Medical Problems of the North of the Krasnoyarsk Scientific Center of the Siberian Branch of the Russian Academy of Sciences</institution></aff></aff-alternatives><aff-alternatives id="aff4"><aff><institution xml:lang="en">Krasnoyarsk State Agricultural University</institution></aff><aff><institution xml:lang="ru">Красноярский государственный аграрный университет</institution></aff><aff><institution xml:lang="zh">Krasnoyarsk State Agricultural University</institution></aff></aff-alternatives><pub-date date-type="preprint" iso-8601-date="2025-02-02" publication-format="electronic"><day>02</day><month>02</month><year>2025</year></pub-date><pub-date date-type="pub" iso-8601-date="2024-12-26" publication-format="electronic"><day>26</day><month>12</month><year>2024</year></pub-date><volume>31</volume><issue>7</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><issue-title xml:lang="zh"/><fpage>521</fpage><lpage>531</lpage><history><date date-type="received" iso-8601-date="2024-05-30"><day>30</day><month>05</month><year>2024</year></date><date date-type="accepted" iso-8601-date="2025-01-12"><day>12</day><month>01</month><year>2025</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2024, Eco-Vector</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2024, Эко-Вектор</copyright-statement><copyright-statement xml:lang="zh">Copyright ©; 2024,</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="en">Eco-Vector</copyright-holder><copyright-holder xml:lang="ru">Эко-Вектор</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-nc-nd/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://hum-ecol.ru/1728-0869/article/view/633016">https://hum-ecol.ru/1728-0869/article/view/633016</self-uri><abstract xml:lang="en"><p><bold>BACKGROUND</bold>: The negative impact of environmental factors affects human health, leading to an increase in disease rates associated with unfavorable living conditions. Assessing environmental quality remains highly relevant, as each major industrial center has its own regional characteristics.</p> <p><bold>AIM</bold>: To compare the cationic and anionic composition and types of saliva microcrystallization in residents of major industrial centers, using Omsk and Krasnoyarsk as examples.</p> <p><bold>MATERIALS AND METHODS</bold>:<bold> </bold>A cross-sectional study was conducted using saliva samples from residents of Omsk (n = 82) and Krasnoyarsk (n = 86), aged 18–22 years. All samples were analyzed for ammonium, potassium, sodium, magnesium, calcium, chlorides, sulfates, fluorides, and phosphates using capillary electrophoresis, and the types of saliva microcrystallization were compared. Statistical analysis was performed using nonparametric methods, including the Mann–Whitney test for two-group comparisons and the Kruskal–Wallis test for comparisons involving three or more groups.</p> <p><bold>RESULTS</bold>: Significant regional differences were observed for all parameters except sulfate concentration in saliva. Residents of Krasnoyarsk had higher levels of ammonium, potassium, calcium, and all anions in their saliva compared to those from Omsk, whereas sodium and magnesium concentrations were higher in Omsk residents. In all parameters except calcium, increased concentrations were observed in male subgroups, regardless of region. No differences in saliva microcrystallization patterns were identified between the two cities.</p> <p><bold>CONCLUSION</bold>: The element concentrations in saliva differ between residents of Omsk and Krasnoyarsk. When planning studies using saliva as a biological substrate, it is essential to consider regional factors that influence its composition, which are determined by varying geochemical and industrial factors. Therefore, it is necessary to refine the normal reference values for saliva parameters specific to each city.</p></abstract><trans-abstract xml:lang="ru"><p><bold>Обоснование</bold>. Негативное влияние факторов окружающей среды отражается на состоянии организма человека, что ведёт к повышению показателей заболеваемости, зависимых от неблагоприятных факторов среды обитания. Оценка качества окружающей среды не теряет своей значимости, для каждого из крупных промышленных центров характерны свои региональные особенности.</p> <p><bold>Цель</bold>. Сравнение катионного и анионного состава и типов микрокристаллизации слюны жителей крупных промышленных центров на примере Омска и Красноярска.</p> <p><bold>Материалы и методы</bold>. Для поперечного исследования использовали образцы слюны жителей Омска (<italic>n</italic>=82) и Красноярска (<italic>n</italic>=86) 18–22 лет. Во всех пробах определяли содержание аммония, калия, натрия, магния, кальция, хлоридов, сульфатов, фторидов, фосфатов методом капиллярного электрофореза, а также проводили сравнение типов микрокристаллизации слюны. Статистическую обработку данных выполняли непараметрическим методом с использованием критерия Манна–Уитни при сравнении двух групп и критерия Краскела–Уоллиса при сравнении трёх и более групп.</p> <p><bold>Результаты</bold>. Между регионами наблюдаются статистически значимые различия по всем показателям, кроме содержания сульфатов в слюне. У жителей Красноярска концентрации ионов аммония, калия, кальция и всех анионов в слюне выше, чем у жителей Омска. Концентрация натрия и магния, напротив, выше у жителей Омска. Для всех показателей, кроме кальция, наблюдается повышение концентрации в подгруппе мужчин, независимо от региона. Различий в показателях микрокристаллизации слюны между городами не выявлено.</p> <p><bold>Заключение</bold>. Установлено, что концентрации элементов в составе слюны жителей Омска и Красноярска различны. При планировании исследований с использованием слюны в качестве биосубстрата необходимо учитывать региональные особенности, влияющие на состав слюны, обусловленные различными геохимическими и промышленными условиями. Таким образом, необходимо уточнение нормальных значений соответствующих показателей слюны для каждого города.</p></trans-abstract><trans-abstract xml:lang="zh"><p>背景。 环境因素的不利影响会对人体健康造成损害，导致受环境不良因素影响的相关疾病发病率上升。环境质量评估仍然具有重要意义，每个大型工业中心都具有其特定的区域特征。</p> <p>研究目的。 比较大型工业城市居民（以鄂木斯克，Omsk 和克拉斯诺亚尔斯克，Krasnoyarsk 为例）的唾液阳离子和阴离子成分及微结晶类型。</p> <p>材料与方法。采用横断面研究方法，收集鄂木斯克（n=82）和克拉斯诺亚尔斯克（n=86） 18-22 岁居民的唾液样本。通过毛细管电泳法检测所有样本中铵、钾、钠、镁、钙、氯离子、硫酸盐、氟化物和磷酸盐的含量，并对唾液的微结晶类型进行比较。数据的统计分析采用非参数方法，对两组数据进行曼-惠特尼（Mann–Whitney）检验，对三组及以上数据进行克拉斯克尔–沃利斯（Kruskal–Wallis）检验。</p> <p>结果。除唾液中硫酸盐含量外，其他所有指标在不同地区间均存在统计学显著差异。克拉斯诺亚尔斯克居民的唾液中铵、钾、钙和所有阴离子的浓度高于鄂木斯克居民，而鄂木斯克居民的钠和镁浓度更高。除钙外，所有指标在男性亚组中均呈现出更高的浓度，且这一趋势不受地区影响。两座城市间的唾液微结晶类型未见显著差异。</p> <p>结论。研究发现，鄂木斯克和克拉斯诺亚尔斯克居民唾液中的矿物元素含量存在差异。在以唾液作为生物基质进行研究时，应考虑因不同地球化学和工业条件所导致的区域特征对唾液成分的影响。因此，有必要针对不同城市进一步明确相应的唾液正常参考值。</p></trans-abstract><kwd-group xml:lang="en"><kwd>saliva</kwd><kwd>capillary electrophoresis</kwd><kwd>cations</kwd><kwd>anions</kwd><kwd>microcrystallization</kwd><kwd>monitoring</kwd><kwd>mineral composition</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>слюна</kwd><kwd>капиллярный электрофорез</kwd><kwd>катионы</kwd><kwd>анионы</kwd><kwd>микрокристаллизация</kwd><kwd>мониторинг</kwd><kwd>минеральный состав</kwd></kwd-group><kwd-group xml:lang="zh"><kwd>唾液</kwd><kwd>毛细管电泳</kwd><kwd>阳离子</kwd><kwd>阴离子</kwd><kwd>微结晶</kwd><kwd>监测</kwd><kwd>矿物成分</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Lyakhovenko OI, Chulkov DI. The main environmental problems of Russian cities and the strategy for resolving them. Russian Political Science. 2017;(3):21–26. (In Russ.) EDN: YRGRDZ</mixed-citation></ref><ref id="B2"><label>2.</label><mixed-citation>Korotkov PA, Trubyanov AB, Gismieva AI, et al. Relationship between the incidence of socially significant diseases and sanitary and ecological parameters of the environment throughout municipal entities in the Mari El Republic. Ekologiya cheloveka (Human ecology). 2022;29(8):577–585. doi: 10.17816/humeco89724 EDN: QCOMDU</mixed-citation></ref><ref id="B3"><label>3.</label><mixed-citation>Karelin AO, Lomtev AYu, Volkodaeva MV, Yeremin GB. The improvement of approaches to the assessment of effects of the anthropogenic air pollution on the population in order to management the risk for health. Gigiena i Sanitaria (Hygiene and Sanitation, Russian journal). 2019;98(1):82–86. doi: 10.18821/0016-9900-2019-98-1-82-86 EDN: YWAHHV</mixed-citation></ref><ref id="B4"><label>4.</label><mixed-citation>Klepikov OV, Samoylov AS, Ushakov IB, et al. Comprehensive assessment of the industrial environment of the industrial city. Gigiena i Sanitaria (Hygiene and Sanitation, Russian journal). 2018;97(8):686–692. doi: 10.18821/0016-9900-2018-97-8-686-692 EDN: YBKAWT</mixed-citation></ref><ref id="B5"><label>5.</label><mixed-citation>Fadeev VA, Kochurov BI, Ermolaev IK, Lobkovsky VA. On the possible change in the dynamic balance of the environment to improve the ecological situation in the Krasnoyarsk and Omsk regions. Problems of regional ecology. 2018;(6):144–148. doi: 10.24411/1728-323X-2019-16144 EDN: PNSYUJ</mixed-citation></ref><ref id="B6"><label>6.</label><mixed-citation>Kolycheva IV, Rychagova OA, Lizarev AV. Impact of labour activity factors on sodium level in saliva of firefighters. Gigiena i Sanitaria (Hygiene and Sanitation, Russian journal). 2015;94(4):44–47. EDN: UHKWAP</mixed-citation></ref><ref id="B7"><label>7.</label><mixed-citation>Savinov SS, Drobyshev AI. Influence of individual and subpopulation factors on the concentration of major and trace elements in saliva. Ekologiya cheloveka (Human ecology). 2022;29(10):689–698. doi: 10.17816/humeco109909 EDN: NAEGBU</mixed-citation></ref><ref id="B8"><label>8.</label><mixed-citation>Markova EO, Koryakina YuP, Farashchuk NF, Kigan MA. Influence of drinking water chemical substances on public health. Vestnik of the Smolensk State Medical Academy. 2023;22(1):239–249. doi: 10.37903/vsgma.2023.1.31 EDN: WBSRHP</mixed-citation></ref><ref id="B9"><label>9.</label><mixed-citation>Sanguos CL, García LG, Suárez OL, et al. Non-invasive biomonitoring of infant exposure to environmental organic pollutants in north-western Spain based on hair analysis. Identification of potential sources. Environmental Pollution. 2023;339:122705. doi: 10.1016/j.envpol.2023.122705</mixed-citation></ref><ref id="B10"><label>10.</label><mixed-citation>Malathi N, Mythili S, Vasanthi HR. Salivary diagnostics: a brief review. ISRN Dentistry. 2014;2014:158786. doi: 10.1155/2014/158786</mixed-citation></ref><ref id="B11"><label>11.</label><mixed-citation>Song M, Bai H, Zhang P, et al. Promising applications of human-derived saliva biomarker testing in clinical diagnostics. International Journal of Oral Science. 2023;15(1):2. doi: 10.1038/s41368-022-00209-w</mixed-citation></ref><ref id="B12"><label>12.</label><mixed-citation>Huang Z, Yang X, Huang Y, et al. Saliva — a new opportunity for fluid biopsy. Clin Chem Lab Med. 2022;61(1):4–32. doi: 10.1515/cclm-2022-0793</mixed-citation></ref><ref id="B13"><label>13.</label><mixed-citation>Sarf EA, Dergacheva MV, Zharkikh LA, Bel'skaya LV. Environmental monitoring using adolescents’ saliva in Omsk. Ekologiya cheloveka (Human ecology). 2021;28(11):12–19. doi: 10.33396/1728-0869-2021-11-12-19 EDN: CYIQXC</mixed-citation></ref><ref id="B14"><label>14.</label><mixed-citation>Kazakova YM, Savostsikava VS. Diagnostic possibilities of studying the crystal structure of biological fluids under various pathological conditions of the organism. Meditsinskiye Novosti. 2023;(2):21–24. EDN: NDODZN</mixed-citation></ref><ref id="B15"><label>15.</label><mixed-citation>Vagner VD, Sarf EA, Belskaya LV, et al. Prognostic significance of oral fluid fluoride measurement in acute pericoronitis. Bulletin of Russian State Medical University. 2022;(4):57–64. doi: 10.24075/vrgmu.2022.042 EDN: GTMSYH</mixed-citation></ref><ref id="B16"><label>16.</label><mixed-citation>Barer GM, Denisov AB. Crystallographic method for studying saliva. Moscow: VUNMC Roszdrav; 2008. (In Russ.) EDN: QKRGUF</mixed-citation></ref><ref id="B17"><label>17.</label><mixed-citation>Belskaya LV. Saliva as an object of clinical laboratory diagnostics. Omsk: Omskblankizdat; 2015. (In Russ.) EDN: XWFHIK</mixed-citation></ref><ref id="B18"><label>18.</label><mixed-citation>Sazonova OV, Sergeev AK, Chupakhina LV, et al. Analyzing health risks caused by contaminated drinking water (experience gained in Samara region). Health Risk Analysis. 2021;(2):41–51. doi: 10.21668/health.risk/2021.2.04 EDN: EFWWCD</mixed-citation></ref><ref id="B19"><label>19.</label><mixed-citation>Belokonova NA, Polushina LG, Lelekova RP. Monitoring the status of water and electrolyte balance of the body. Public Health and Life Environment. 2016;(7):8–11. EDN: WFFZTN</mixed-citation></ref><ref id="B20"><label>20.</label><mixed-citation>Khalatov V.A., Nevzorova E.V., Gulin A.V. Using saliva as test object, ecological-analytical monitoring of trace elements. Tambov University Reports. Series: Natural and Technical Sciences. 2013;18(6-2):3250–3252. EDN: RTWNHL</mixed-citation></ref><ref id="B21"><label>21.</label><mixed-citation>Baryshnikova GA, Chorbinskaya SA, Stepanova II, Blokhina OE. Potassium and magnesium deficiency, its role in cardiovascular disease development and possibilities of correction. Consilium Medicum. 2019;21(1):67–73. doi: 10.26442/20751753.2019.1.19024 EDN: LUGJYU</mixed-citation></ref><ref id="B22"><label>22.</label><mixed-citation>Grigus YaI, Mikhaylova OD, Gorbunov AYu, Vakhrushev YaM. Significance of magnesium in phisiology and pathology of the digestive system. Experimental and Clinical Gastroenterology Journal. 2015;(6):89–94. EDN: UHYNNR</mixed-citation></ref><ref id="B23"><label>23.</label><mixed-citation>Ministry of Natural Resources and Ecology of the Omsk Region. Report on the environmental situation in the Omsk region for 2022. Omsk: Omskblankizdat; 2023. (In Russ.)</mixed-citation></ref><ref id="B24"><label>24.</label><mixed-citation>Ministry of Ecology and Rational Natural Resources Management of the Krasnoyarsk Territory. State report on the state and protection of the environment in the Krasnoyarsk Territory in 2022. Krasnoyarsk: KGBU TsRMPiOOS; 2023. (In Russ.)</mixed-citation></ref><ref id="B25"><label>25.</label><mixed-citation>Yahyaev MA, Salikhov ShK, Abdulkadyrova SO, et al. Contents of magnesium in the environment and population morbidity rate of arterial hypertension. Gigiena i Sanitaria (Hygiene and Sanitation, Russian journal). 2019;98(5):494–497. doi: 10.18821/0016-9900-2019-98-5-4 EDN: DNTINT</mixed-citation></ref><ref id="B26"><label>26.</label><mixed-citation>Boiko VS, Timokhin AYu, Mikhailov VV. Fertility of irrigated lands in the south forest-steppe of the Omsk Region. Taurida Herald of the Agrarian Sciences. 2021;(4):40–49. doi: 10.33952/2542-0720-2021-4-28-40-49 EDN: ZLZCYG</mixed-citation></ref><ref id="B27"><label>27.</label><mixed-citation>Sokolov AV, Kostina DA, Marinchev SS, et al. The significance of detection of nitrites in oral fluid of healthy people. Clinical Laboratory Diagnostics. 2018;63(4):215–219. doi: 10.18821/0869-2084-2018-63-4-215-219 EDN: YXJGRC</mixed-citation></ref><ref id="B28"><label>28.</label><mixed-citation>Michalke B, Rossbach B, Göen T, et al. Saliva as a matrix for human biomonitoring in occupational and environmental medicine. Int Arch Occup Environ Health. 2015;88(1):1–44. doi: 10.1007/s00420-014-0938-5</mixed-citation></ref><ref id="B29"><label>29.</label><mixed-citation>Yadykina TK, Mikhailova NN, Kochergina TV, Zhukova AG. Associations of the 283 A&gt;G (BSMI) polymorphism of the VDR gene with mineral bone tissue density in aluminum industry workers. Russian Journal of Occupational Health and Industrial Ecology. 2022;62(9):579–587. doi: 10.31089/1026-9428-2022-62-9-579-587 EDN: AJTYAB</mixed-citation></ref><ref id="B30"><label>30.</label><mixed-citation>Kudaeva IV, Dyakovich OA, Beygel EA, et al. Clinical, biochemical and allergological indices characterizing occupational diseases of the bronchial and pulmonary system in employees at aluminium production. Gigiena i Sanitaria (Hygiene and Sanitation, Russian journal). 2016;95(12):1142–1145. doi: 10.18821/0016-9900-2016-95-12-1142-1145 EDN: XQRZPD</mixed-citation></ref><ref id="B31"><label>31.</label><mixed-citation>Saeed OAS. Differences in the microcrystallization of the oral fluid of patients with bacterial and viral infections. Meditsinskiye Novosti. 2022;(4):52–54. EDN: WPCSWL</mixed-citation></ref></ref-list></back></article>
