Vol. 337 No. 7 (2026)

DOI https://doi.org/10.18799/24131830/2026/7/5203

Environmental risks of pollution of the Modonkul River bottom sediments, South-Western Transbaikalia

The planning of water management measures in the Modonkul River Basin require a comprehensive studying the heavy metal pollution of bottom sediments flowing through the drainage runoff area of ​​ore deposits and waste from their development.  Aim. To determine the environmental risks of pollution of bottom sediments, which can be a source of secondary pollution of surface waters and toxicity to biota. Object. The bottom sediments of the Modonkul River. Method. X-ray fluorescence analysis. Results and conclusions. It was established that when compared the mouth with the upper reaches of the river, the environmental risks of pollution of bottom sediments increase downstream. The accumulation of Cd in bottom sediments increases by 6.3, Cu – 3.2, As – 2.0, Co – 1.5, Pb – 1.8, Mn – 1.5 times. According to the value of the geoaccumulation index, Cd accumulations vary from weak to strong pollution, Pb – from weak to moderate pollution, Cu – weak pollution. The indicators of total pollution and additional load of heavy metals in bottom sediments increase by 3.63 times. According to the classification of the degree of pollution by heavy metals, bottom sediments are characterized as objects of strong pollution. The ecological risk of toxicity of bottom sediments increases by 4.6–5.4 times. During the formation of bottom sediments, the lithogenic contribution decreases for Cd, Pb, Cu to 4–17%, for As, Ni, Zn, Mn to 40–67%. The lithogenic contribution of Co varies within 77–90%.

For citation: Khazheeva Z.I., Doroshkevich S.G., Plyusnin A.M. Environmental risks of pollution of the Modonkul River bottom sediments, South-West Transbaikalia. Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2026, vol. 337, no. 7, pp. 49-57. https://doi.org/10.18799/24131830/2026/7/5203

Keywords:

heavy metals, bottom sediment pollution, additional load, environmental risks, toxicity

Authors:

Zinaida I. Khazheeva

Svetlana G. Doroshkevich

Alexey M. Plyusnin

References:

1. Airiyants A.A., Bortnikova S.B. Storage of sulfide-containing enrichment waste as a source of heavy metals (Zn, Pb, Cu, Cd) in the environment. Chemistry for Sustainable Development, 2000, no. 8, pp. 315–326. (In Russ.)

2. Bortnikova S.B., Gaskova O.L., Bessonova E.P. Geochemistry of technogenic systems. Novosibirsk, Academic Publishing House ¨GEO", 2006. 169 p. (In Russ.)

3. Plyusnin A.M., Garipova E.R., Ukraintsev A.V., Dabaeva V.V. Toxic elements in surface and underflow waters of the rivers of the Dzhida natural-technogenic system. Bulletin of the Voronezh State University. Series: Geography. Geoecology, 2025, no. 11, pp. 150–160. (In Russ.) DOI: 10.17308/geo/1609-0683/2025/1/150-160.

4. Plyusnin A.M., Voronina Yu.S., Ukraintsev A.V., Chernyavskii M.K., Peryazeva E.G., Chebykin E.P. Atmospheric pollution from a storage of tungsten–molybdenum ore mining and processing wastes. Geochemistry International, 2023, vol. 61, pp. 1293–1307. DOI: 10.1134/S0016702923110095.

5. Voronina Yu.S., Plyusnin A.M., Chudinova O.N. Chemical and mineral composition of solid snow sediment on the territory of the Dzhida tungsten-molybdenum plant. Geospheric studies, 2025, no. 4, pp. 35–48. (In Russ.)

6. Fuentes-López J.M., Olías M., León R., Basallote M.D., Macías F., Moreno-González R., Cánovas C.R. Stream-pit lake interactions in an abandoned mining area affected by acid drainage (Iberian Pyrite Belt). Science of the Total Environment, 2022, vol. 833, p. 155224. DOI: 10.1016/j.scitotenv.2022.155224.

7. Rybnikova L.S., Rybnikov P.A., Navolokina V.Yu. Migration of chemical elements in groundwater of a mining area. Bulletin of Tomsk Polytechnic University. Geo Assets Engineering, 2024, vol. 335, no. 9, pp. 137–147. (In Russ.) DOI: 10.18799/24131830/2024/9/4465.

8. Adimalla N., Gao Y., Wang Z., Quan H. Spatial distribution, contamination characteristics and potential ecological risk assessment of trace metals in surface soils of south-central stretch of India. Water Air and Soil Pollution, 2024, vol. 235, p. 522. DOI: 10.1007/s11270-024-07344-6.

9. Peng J.Y., Zhang S., Han Y.Y., Bate B., Ke H., Chen Y.M. Soil heavy metal pollution of industrial legacies in China and health risk assessment. Science of the Total Environment, 2022, vol. 816, p. 151632. DOI: 10.1016/j.scitotenv.2021.151632.

10. Gordienko I.V., Filimonov A.V., Minina O.R., Gornova M.A., Medvedev A.Ya., Klimuk V.S., Elbaev A.L., Tomurtogoo O. Dzhida island-arc system of the Paleo-Asian ocean: structure and main stages of geodynamic evolution in the Vendian-Paleozoic. Geology and Geophysics, 2007, vol. 48, no. 1, pp. 120–140. (In Russ.)

11. Mats D.V., Ufimtsev G.F., Mandelbaum M.M. Cenozoic of the Baikal rift basin. Structure and geological history. Novosibirsk, Siberian Branch of the Russian Academy of Sciences Publ. house, 2001. 252 p. (In Russ.)

12. Smirnova O.K., Plyusnin A.M. Dzhidinsky ore region (environmental issues). Ulan-Ude, Publishing house of BSC SB RAS, 2013. 181 p. (In Russ.)

13. Damdinova L.B., Damdinov B.B., Xiao-Wen Huang, Bryansky N.V., Khybanov V.B., Yudin D.S. Age, Conditions of formation and fluid composition of the Pervomaiskoe molybdenum deposit (Dzhidinskoe Ore Field, South-Western Transbaikalia, Russia). Minerals, 2019, no. 9, pp. 572–592. DOI: 10.3390/min11070725.

14. Surface Water Resources of the USSR, Angara-Yenisei Region. Iss. 3. Lake Baikal Basin (Transbaikalia). Leningrad, Gidrometeoizdat Publ., 1973. Vol. 16, 400 p. (In Russ.)

15. Khazheeva Z.I. Chemical composition of the Modonkul River water in modern conditions. Mining Information and Analytical Bulletin, 2017, no. 6, pp. 183–187. (In Russ.)

16. Khazheeva Z.I., Plyusnin A.M., Smirnova O.K., Peryazeva E.G., Zhambalova D.I., Doroshkevich S.G., Dabaeva V.V. Mining activities and the chemical composition of R. Modonkul, Transbaikalia. Water (Switzerland), 2020, vol. 12, no 4, pp. 979–998. DOI: 10.3390/W12040979.

17. Khazheeva Z.I., Plyusnin A.M., Dampilova B.V. Changes in the water quality of the Modonkul River according to the combinatorial pollution index. Water Resources, 2024, vol. 51, no. 4, pp. 485–497. (In Russ.) DOI: 10.1134/S0097807824700921.

18. Kiełbasa A., Buszewski B. River bottom sediment from the Vistula as matrix of candidate for a new reference material. Ecotoxicology and Environmental Safety, 2017, vol. 142, pp. 237–242. DOI: 10.1016/j.ecoenv.2017.03.007

19. Qiu Y.W. Bioaccumulation of heavy metals both in wild and mariculture food chains in Day Bay, South China. Estuar. Coast. Shelf Sci., 2015, vol. 512, pp. 143–153. DOI: 10.1016/j.ecss.2015.05.036

20. Gitau M.W., Chen J., Ma Z. Water quality indices as tools for decision making and management. Water Resours. Manag., 2016, vol. 30, pp. 2591–2610. DOI: 10.1007/s11269-016-1311-0

21. Reshetnyak O.S., Zakrutkin V.E. Bottom sediments as a source of secondary pollution of river waters with metals (according to laboratory experiment data). News of Higher Education Institutions. North Caucasian Region. Natural Sciences, 2016, no. 4, pp. 102–109. (In Russ.)

22. Tereshchenko N.N., Chuzhikova-Proskurina O.D., Proskurin V.Yu. Heavy metals and metalloids in water and bottom sediments in the rivers of the Can Gio Biosphere Reserve (Vietnam). Water Resources, 2023, vol. 50, no. 2, pp. 232–246. (In Russ.) DOI: 10.31857/S0321059623020153

23. Ecological and geographical atlas-monograph "Selenga-Baikal". Ed. by N.S. Kasimov. Moscow, Faculty of Geography, Moscow State University Publ., 2019. 288 p. (In Russ.)

24. Müller G. Index of geoaccumulation in the sediments of the Rhine River. Geo J., 1969, vol. 2, pp. 108–118.

25. Hakanson L. An ecological risk index for aquatic pollution control. A sedimentological approach. Water Res., 1980, vol. 14, pp. 975–1001. DOI: 10.1016/0043-1354(80)90143-8.

26. Abrahim G.M., Parker R.J. Assessment of heavy metal enrichment factors and the degree of contamination in marine sediments from Tamaki Estuary, Auckland, New Zealand. Environ. Monit. Assess., 2008, vol. 136, pp. 227–238. DOI: 10.1007/s10661-007-9678-2.

27. Çevik F., Göksu M.Z.L., Derici O.B., Findik Ö. An assessment of metal pollution in surface sediments of Seyhan dam by using enrichment factor, geoaccumulaiton index and statistical analyses. Environ. Monit. Assess., 2009, vol. 152, pp. 309–317. DOI: 10.1007/s10661-008-0317-3.

28. Zhang W., Jin X., Di Z., Zhu X., Shan B. Heavy metals in surface sediments of the shallow lakes in eastern China: their relations with environmental factors and anthropogenic activities. Environ. Sci. Pollut. Res., 2016, vol. 23, pp. 25364–25373. DOI: 10.1007/s11356-016-7643-8.

29. Varol M. Assessment of heavy metal contamination in sediments of the Tigris River (Turkey) using pollution indices and multivariate statistical techniques. J. Hazard Mater., 2011, vol. 195, pp. 355–364. DOI: 10.1016/j.jhazmat.2011.08.051.

30. Forstner U., Ahlf W., Calmano W. Sediment quality objectives and criteria development in Germany. Water Sci. Technol. 1993, vol. 28, pp. 307–316. DOI: 10.2166/wst.1993.0629.

31. Singh M., Müller G., Singh I.B. Heavy metals in freshly deposited stream sediments of rivers associated with urbanization of the Ganga Plain, India. Water Air Soil Poll., 2002, vol. 141, pp. 35–54. DOI: 10.1023/A:1021339917643.

32. Liu S., Tian S., Li K., Wang L., Liang T. Heavy metal bioaccessibility and health risks in the contaminated soil of an abandoned, small-scale lead and zinc mine. Environ. Sci. Pollut. Res., 2018, vol. 25, pp. 15044–15056. DOI: 10.1007/s11356-018-1660-8.

33. Spurgeon D.J., Rowland P., Ainsworth G., Rothery P., Long S., Black H.I. Geographical and pedological drivers of distribution and risks to soil fauna of seven metals (Cd, Cu, Cr, Ni, Pb, V and Zn) in British soils. Environ. Pollut., 2008, vol. 153, pp. 273–283. DOI: 10.1016/j.envpol.2007.08.027.

34. Qian Y., Zheng M., Gao L., Zhang B., Liu W., Jiao W., Zhao X., Xiao K. Heavy metal contamination and its environmental risk assessment in surface sediments from Lake Dongting, People’s Republic of China. Bull. Environ. Contam. Toxicol., 2005, vol. 75, pp. 204–210. DOI: 10.1007/s00128-005-0739-3.

35. Wang Y., Chen P., Cui R., Si W., Zhang Y., Ji W. Heavy metal concentrations in water, sediment, and tissues of two fish species (Triplohysa pappenheimi, Gobio hwanghensis) from the Lanzhou section of the Yellow River, China. Environ. Monit. Assess., 2010, vol. 165, pp. 97–102. DOI: 10.1007/s 10661-009-0929-2.