Arsenic and fluoride co-enrichment of groundwater in the loess areas and associated human health risks: A case study of Dali County in the Guanzhong Basin

Abstract

This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin. Key findings are as follows: (1) Groundwater samples with high arsenic and fluoride concentrations collected from the loess area and the terraces of the Weihe River accounted for 26% and 30%, respectively, of the total samples, with primary hydrochemical type identified as HCO₃-Na. The karst and sand areas exhibit relatively high groundwater quality, serving as preferred sources for water supply. It is recommended that local governments fully harness groundwater in these areas; (2) groundwater with high arsenic and fluoride concentrations in the loess area and the alluvial plain of rivers in Dali County is primarily distributed within the Guanzhong Basin, which represents the drainage zone of groundwater; (3) arsenic and fluoride in groundwater originate principally from natural and anthropogenic sources; (4) the human health risk assessments reveal that long-term intake of groundwater with high arsenic and fluoride concentrations pose cancer or non-cancer risks, which are more serious to kids compared to adults. This study provides a theoretical basis for the prevention and treatment of groundwater with high arsenic and fluoride concentrations in loess areas.

Keywords

Arsenic / Fluoride / Groundwater / Cancer risk / Kid and adult / Human health risk assessment / Hydrogeological survey engineering / Environmental geological survey engineering / Loess areas

CRediT authorship contribution statement

Rui-ping Liu and Jian-Gang Jiao wrote the manuscript. Others helped Rui-ping Liu conceive the original idea of this study. El-Wardany RM polished this manuscript.

Declaration of competing interest

The authors declare no conflict of interest.

Acknowledgment

This study was funded by the ministry-province cooperation-based pilot project entitled A Technological System for Ecological Remediation Evaluation of Open-Pit Mines initiated by the Ministry of Natural Resources in 2023 (2023-03), survey projects of the Land and Resources Investigation Program ([2023]06-03-04, 1212010634713), and a key R&D projects of Shaanxi Province in 2023 (2023-ZDLSF-63). The authors would like to extend their gratitude to the Experiment and Testing Laboratory of Xi'an Center, China Geological Survey for the statistical data analyses.

References

[1] Berger T, Mathurin FA, Drake H, Åström ME. 2016. Fluoride abundance and controls in fresh groundwater in Quaternary deposits and bedrock fractures in an area with fluorine-rich granitoid rocks. Science of the Total Environment, 569-570, 948-960. doi: 10.1016/j.scitotenv.2016.06.002.

[2] Chen HH, Chen HW, He JT. 2006. Health-based risk assessment of contaminated sites: Principles and methods. Earth Science Frontiers, 13(1), 216-223 doi: 10.1016/S1872-2040(06)60041-8. (in Chinese with English abstract).

[3] Chen J, Qian H, Wu H. 2017. Health risk assessment of water environment in drinking groundwater well fields based on triangular fuzzy number theory. South - to - North Water Transfers and Water Science and Technology, 15(03), 80-85 doi: 10.13476/j.cnki.nsbdqk.2017.03.014. (in Chinese with English abstract).

[4] Chen J, Qian H, Wu H. Gao Y, Li X. 2017. Assessment of arsenic and fluoride pollution in groundwater in Dawukou area, Northwest China, and the associated health risk for inhabitants. Environmental Earth Sciences, 76, 314. doi: 10.1007/s12665-017-6629-2.

[5] Dong SG, Liu BW, Chen Y, Ma MY, Liu XB, Wang C. 2022. Hydrogeochemical control of high arsenic and fluoride groundwater in arid and semi-arid areas: A case study of Tumochuan Plain, China. Chemosphere, 301, 134657. doi: 10.1016/j.chemosphere.2022.134657.

[6] Deng AQ, Dong ZM, Gao Q, Hu JY. 2017. Health risk assessment of arsenic in groundwater across China. China Environmental Science, 37(9), 3556-3565.

[7] Estrada-Capetillo BL, Ortiz-Perez MD, Salgado-Bustamante M, Calderón-Aranda E, Rodríguez-Pinala CJ, Reynaga-Hernández E, Corral-Fernandez NE, González-Amaro R, Portales-Perez DP. 2014. Arsenic and fluoride co-exposure affects the expression of apoptotic and inflammatory genes and proteins in mononuclear cells from children. Mutation Research, 731, 27-34. doi: 10.1016/j.mrgentox.2014.01.006.

[8] Gao YY, Qian H, Wang HK, Chen J, Ren WH, Yang FX. 2020. Assessment of background levels and pollution sources for arsenic and fluoride in the phreatic and confined groundwater of Xi'an city, Shaanxi, China. Environmental Science and Pollution Research, 27, 34702-34714. doi: 10.1007/s11356-019-06791-7.

[9] Gao YY. 2020. Spatio-temporal evolution of hydrochemical components and human health risk assessment of groundwater in Guanzhong Plain. A dissertation submitted for the degree of doctor of Chang'an University. 1-196 doi: 10.26976/d.cnki.gchau.2020.000029. (in Chinese with English abstract).

[10] Guo HM, Ni P, Jia YF. 2014. Types, chemical characteristics, and genesis of geogenic high-arsenic groundwater in the world. Earth Science Frontiers, 21(4), 1-12. doi: 10.13745/j.esf.2014.04.001.

[11] He XD, Li PY, Ji YJ, Wang YH, Su ZM, Elumalai V. 2020. Groundwater arsenic and fluoride and associated arsenicosis and fluorosis in China: Occurrence, distribution and management. Exposure and Health 12, 355-368. doi: 10.1007/s12403-020-00347-8.

[12] Hossain M, Patra PK. 2020. Contamination zoning and health risk assessment of trace elements in groundwater through geostatistical modelling. Ecotoxicology and Environmental Safety, 189, 110038. doi: 10.1016/j.ecoenv.2019.110038.

[13] Institute of Geology and Geophysics, China Academy of Sciences. 2020. Global Distribution and Hazards of High Arsenic Groundwater http://www.igg.cas.cn/xwzx/cutting_edge/202008/t20200824_5671956.html. (in Chinese).

[14] IPCS (International Programme on Chemical Safety). 2001. Arsenic and arsenic compounds. http://www.inchem.org/documents/ehc/ehc/ehc224.html.

[15] Liu RP. 2009. Study on transference and transform simulation of fluoride in groundwater and relation between fluoride and human body health in Dali Region, Guanzhong Basin. Xi'an, Chang'an University, Master' thesis, 1-65. (in Chinese with English abstract).

[16] Liu RP, Zhu H, Yang BC, Zhao AN. 2008. Occurrence pattern and hydrochemistry cause of the shallow groundwater fluoride in the Dali County, Shaanxi Province. Northwestern Geology, 41(4), 134-141 doi: 10.3969/j.issn.1009-6248.2008.04.010. (in Chinese with English abstract).

[17] Liu RP, Zhu H, Liu F, Dong Y, El-Wardany RM. 2021. Current situation and human health risk assessment of fluoride enrichment in groundwater in the Loess Plateau: A case study of Dali County, Shaanxi Province, China. China Geology, 3(3), 487-497. doi: 10.31035/cg2021051.

[18] Li YM. 2021. Distribution and harm of high arsenic groundwater in the world, http://www.igg.cas.cn/xwzx/cutting_edge/202008/t20200824_5671956.html. (in Chinese)

[19] Ministry of Environment Protection. 2013. Exposure factors hand book of Chinese population. adult volume. Beijing, China Environmental Science Press, 1-265.

[20] Rehman IU, Ishag M, Ali L. 2018. Enrichment, spatial distribution of potential ecological and human health risk assessment via toxic metals in soil and surface water ingestion in the vicinity of Sewakht mines, district Chitral, Northern Pakistan. Ecotoxicology and Environmental Safety, 154: 127-136. doi: https://doi.org/10.1016/j.ecoenv.2018.02.033.

[21] Ren Y, Cao WG, Pan D. 2021. Evolution characteristics and change mechanism of arsenic and fluorine in shallow groundwater from a typical irrigation area in the lower reaches of the Yellow River (Henan) in 2010-2020. Rock and Mineral Analysis, 40 (6), 846-859 doi: 10.15898/j.cnki.11-2131/td.202110090143. (in Chinese with English abstract).

[22] Su X, Wang H, Zhang Y. 2013. Health risk assessment of nitrate contamination in groundwater: A case study of an agricultural area in northeast China. Water Resources Management, 27(8), 3025-3034. doi: https://doi.org/10.1007/s11356-019-07075-w.

[23] Sun Y, Zhou JL, Yang FY. 2022. Distribution and co-enrichment genesis of arsenic, fluorine, and iodine in groundwater of the oasis belt in the southern margin of Tarim Basin. Earth Science Frontiers, 29 (3), 099-114. doi: 10.13745/j.esf.sf.2022.1.33.

[24] US EPA. 2011. Exposure Factors Handbook (2011 Edition). Washington:U.S. Environmental Protection Agency. USEPA.1993. Reference Dose (RfD): Description and Use in Health Risk Assessments. Background Document 1A. https://www.epa.gov/iris/reference-dose-rfd-description-and-use-health-risk-assessments#main-content. March, 1993.

[25] USEPA. 2005. Guidelines for carcinogen risk assessment. Risk assessment forum. United States Environmental Protection Agency, Washington, DC. EPA/630/P-03/001F. March, 2005.

[26] USEPA. 2024. Regional Screening Levels (RSLs) - Generic Tables. https://www.epa.gov/risk/regional-screening-levels-rsls-generic-tables. May 2024.

[27] Wang D. 2016. Spatial distribution and factors of fluoride groundwater in Chengcheng County, Shaanxi Province, Jilin University, Changchun, Master's thesis, 1-86 (in Chinese with English abstract).

[28] Wang YY, Cao WG, Pan D, Wang S, Ren Y, Li ZY. 2022. Distribution and origin of high arsenic and fluoride in groundwater of the north Henan Plain. Rock and Mineral Analysis, 41(6), 1095-1109 doi:10.15898/j.cnki.11-2131/td.202110090141. (in Chinese with English abstract).

[29] Wang Z, Chai L, Wang YY, Yang Z, Wang H, Wu X. 2011. Potential health risk of arsenic and cadmium in groundwater near Xiangjiang River, China: A case study for risk assessment and management of toxic substances. Environmental Monitoring and Assessment, 175(1-4), 167-173. doi: 10.1007/s10661-010-1503-7.

[30] Wu J, Li J, Teng Y, Chen H, Wang Y. 2020. A partition computingbased positive matrix factorization (PC-PMF) approach for the source apportionment of agricultural soil heavy metal contents and associated health risks. Journal of Hazardous Materials, 121766 doi: 10.1016/j.jhazmat.2019.121766. (in Chinese with English abstract).

[31] WHO World Health Organization. 2011. Arsenic in drinking-water: Background document for development of WHO guidelines for drinking-water quality. Switzerland, WHO Press.

[32] Wang YX, Li JX, Ma T. 2021. Genesis of geogenic contaminated groundwater: As, F and I. Critical Reviews in Environmental Science and Technology, 51(24), 2895-2933. doi: 10.1080/10643389.2020.1807452.

[33] Xiong J, Han ZW, Wu P, Zeng, X, Luo G, Yang W. 2020. Spatial distribution characteristics, contamination evaluation and health risk assessment of arsenic and antimony in soil around an antimony smelter of Dushan County. Acta Scientiae Circumstantiae, 40(2), 655-664. doi: 10.13671/j.hjkxxb.2019.0387.

[34] Xue CZ, Xiao L, Wu QF, Li DY, Wang KX, Li HG, Wang R. 1986. Studies of Background Values of Ten Chemical Elements in Major Agricultural Soils in Snaanxi Province, 14(3), 1-24.

[35] Yu Q, Zhang Y, Dong T, Wu GW, Li P. 2023. Effect of Surface WaterGroundwater Interaction on Arsenic Transport in Shallow Groundwater of Jianghan Plain. Earth Science. 48(09), 3420-3431 https://kns.cnki.net/kcms/detail/42.1874.P.20220506.1102.010.html. (in Chinese with English abstract).

[36] Zango MS, Sunkari ED, Abu M. 2019. Hydrogeochemical controls and human health risk assessment of groundwater fluoride and boron in the semi-arid North East region of Ghana. Journal of Geochemical Exploration, 207, 106363. doi: 10.1016/j.gexplo.2019.106363.

[37] Zhang ZJ, Fei NH, Chen ZY. 2009. Investigation and evaluation of sustainable utilization of groundwater in North China Plain. Beijing, Geological Publishing House, 35-40 (in Chinese).

[38] Zhou YZ, Guo HM, Zhang Z. 2018. Characteristics and implication of stable carbon isotope in high arsenic groundwater systems in the northwest Hetao Basin, Inner Mongolia, China. Journal of Asian Earth Sciences, 163, 70-79. doi: 10.1016/j.jseaes.2018.05.018.

[39] Zeng SY, Ma J, Yang YJ. 2019. Spatial assessment of farmland soil pollution and its potential human health risks in China. Science of the Total Environment, 687, 642-653. doi: 10.1016/j.scitotenv.2019.05.291.

[40] Zhou JM, Jiang ZC, Xu GL, Qin XQ. Huang QB, Zhang LK. 2019. Distribution and health risk assessment of metals in groundwater around iron mine. China Environmental Science, 39(5), 1934-1944. doi: 10.19674/j.cnki.issn1000-6923.2019.0230.

[41] Zhu H, Yang BC, Zhao AN, Ke HL, Qiao G. 2010. The formation regularity of high-fluorine groundwater in Dali County, Shaanxi Province. Geology in China, 37(03), 672-676 doi: 10. 1016/S1876-3804(11)60004-9. (in Chinese with English abstract).