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Huang Z, Wang C, Liu G, Yang L, Luo X, Liang Y, Wang P, Zheng M. Unintentionally-produced persistent organic pollutants in the aquatic environment contaminated from historical chlor-alkali production. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 361:124882. [PMID: 39241952 DOI: 10.1016/j.envpol.2024.124882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 08/30/2024] [Accepted: 09/01/2024] [Indexed: 09/09/2024]
Abstract
Historical chlor-alkali production has led to substantial concentrations of persistent organic pollutant residues in the environment. This study systematically investigated the distribution of polycyclic aromatic hydrocarbons (PAHs), chlorinated/brominated-PAHs (Cl/Br-PAHs), polychlorinated naphthalenes (PCNs), and hexachlorobutadiene (HCBD) in sediment, lotus (Nelumbo nucifera), and fish samples from Ya-Er Lake, which is a site in China with historical chlor-alkali contamination. The average concentrations [(4.97-1.47) × 103 ng/g dry weight (dw)] of these pollutants in backfill sediments, which were dredged from the lake after chlor-alkali production stopped, were 2.68-70.87 times those in fresh lake sediments (0.622-218 ng/g dw) and reported concentrations in other areas. Correlation analyses indicated that Cl-PAHs, Br-PAHs, and PCNs likely originated from halogenation of parent PAHs in the study area, and the chlorination ratios were larger than those of bromination. The Cl(1/2/3)-PAHs/PAHs and Br(1)-PAHs/PAHs ratios were higher than those for PAHs with more halogen atoms. This contamination extended into the biota, with notable pollutant burdens found in lotus (Nelumbo nucifera, 0.305-77.3 ng/g dw) and even higher concentrations in fish (2.20-345 ng/g lipid weight). Estimated biological soil accumulation factors revealed significant enrichment in lotus organs (mean: 7.19) and fish muscle (mean: 10.65), especially the latter, which highlighted bioaccumulation and potential food chain transfer risks. The estimated daily intakes of PAHs, Cl/Br-PAHs, and HCBD through fish consumption currently pose negligible risks, while dietary intake of PCNs may present health concerns. Continuous monitoring and impact assessments are crucial for developing appropriate risk management strategies to safeguard public health.
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Affiliation(s)
- Zichun Huang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Institute of Environment and Health, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, 310024, China; College of Resource and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chu Wang
- Changjiang Survey, Planning, Design and Research Co., Ltd, Wuhan, 430010, China
| | - Guorui Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Institute of Environment and Health, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, 310024, China; College of Resource and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lili Yang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Institute of Environment and Health, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, 310024, China; College of Resource and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xi Luo
- Changjiang Survey, Planning, Design and Research Co., Ltd, Wuhan, 430010, China
| | - Yong Liang
- Jianghan University, Hubei, 430056, China
| | - Pu Wang
- Jianghan University, Hubei, 430056, China
| | - Minghui Zheng
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Institute of Environment and Health, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, 310024, China; College of Resource and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
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Tang Y, Tao D, Li G, Ye C, Bu Z, Shen R, Lin Y, Lv W. Formation behavior of PCDD/Fs during waste pyrolysis and incineration: Effect of temperature, calcium oxide addition, and redox atmosphere. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 350:124011. [PMID: 38641034 DOI: 10.1016/j.envpol.2024.124011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/13/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
The clean and efficient utilization of municipal solid waste (MSW) has attracted increasing concerns in recent years. Pyrolysis of MSW is one of the promising options due to the production of high-value intermediates and the inhibition of pollutants at reducing atmosphere. Herein, the formation behavior of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during MSW pyrolysis and incineration was experimentally investigated and compared. The influence of reaction temperature, CaO addition, and redox atmosphere on PCDD/Fs formation were compared and discussed. The results showed as the pyrolysis temperature increased, the mass concentration and international toxicity equivalence quantity of PCDD/Fs initially peaked at ∼750 °C before declining. Most of the generated PCDD/Fs were concentrated in the liquid and gaseous products, accounting for ∼90% of the total. Among liquid products, octachlorodibenzo-p-dioxin (O8CDD), 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,4,6,7,8-heptachlorodibenzofuran (H7CDF) were the most crucial mass concentration contributors, while in gas products, high-chlorinated PCDD/Fs, such as O8CDD, octachlorodibenzofuran (O8CDF) and 1,2,3,4,6,7,8-H7CDF were predominant. Compared to incineration, the formation of PCDD/Fs was 7-20 times greater than that from pyrolysis. This discrepancy can be attributed to the hydrogen-rich and oxygen-deficient atmosphere during pyrolysis, which effectively inhibited the Deacon reaction and the formation of C-Cl bonds, thereby reducing the active chlorine in the system. The addition of in-situ CaO additives also decreased the active chlorine content in the system, bolstering the inhibiting of PCDD/Fs formation during MSW pyrolysis.
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Affiliation(s)
- Yuanjun Tang
- Department of Energy and Environment System Engineering, Zhejiang University of Science and Technology, Hangzhou, 310023, China.
| | - Dongsheng Tao
- Zhejiang Ecowell Energy Management Technology Co., Ltd. Hangzhou, Zhejiang, 310012, China
| | - Guoneng Li
- Department of Energy and Environment System Engineering, Zhejiang University of Science and Technology, Hangzhou, 310023, China
| | - Chao Ye
- Department of Energy and Environment System Engineering, Zhejiang University of Science and Technology, Hangzhou, 310023, China
| | - Zhongming Bu
- Department of Energy and Environment System Engineering, Zhejiang University of Science and Technology, Hangzhou, 310023, China
| | - Rong Shen
- Department of Energy and Environment System Engineering, Zhejiang University of Science and Technology, Hangzhou, 310023, China
| | - Yonghui Lin
- Zhejiang Ecowell Energy Management Technology Co., Ltd. Hangzhou, Zhejiang, 310012, China
| | - Wei Lv
- Zhejiang Ecowell Energy Management Technology Co., Ltd. Hangzhou, Zhejiang, 310012, China
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Xie W, Li W, Wang P, Hao Y, Chen B, Hu L, Wang T, Zhang Q, Liang Y, Jiang G. Unexpected Dioxin Formation During Digestion of Soil with Oxidizing Acids. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:14717-14725. [PMID: 37682840 DOI: 10.1021/acs.est.3c03682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
Dioxins, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), are among the most toxic unintentionally produced persistent organic pollutants, and their emission is of great concern. Herein, we discovered abundant dioxin formation in soil and various organic carbon-containing matrices after digestion with aqua regia. Σ17PCDD/Fs concentrations were in the range of 66.6-142,834 pg/g dw (5.6-17,021 pg WHO2005-TEQ/g dw) in 19 soil samples after digestion with aqua regia for 6 h. Σ17PCDD/Fs concentration was significantly and positively correlated with soil organic carbon content (R2 = 0.89; p < 0.01). Compared with cellulose and lignin, humic acid served as an important organic matter component that was converted to PCDD/Fs during soil digestion. Strong oxidation and production of reactive chlorine by aqua regia may be the key factors in the formation of PCDD/Fs. The yearly emission of PCDD/Fs due to digestion with strong acids by the inspection and testing industry was estimated to be 83.8 g TEQ in China in 2021 based on the highest level, which was ∼0.9% of the total dioxin inventory in China. Great attention should be paid to unexpected dioxin formation during digestion processes considering the potential risk of release from laboratories and enterprises.
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Affiliation(s)
- Wenjing Xie
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Wenjuan Li
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Pu Wang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Yanfen Hao
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Bolei Chen
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Ligang Hu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Thanh Wang
- Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping 58183, Sweden
- Department of Thematic Studies─Environmental Change (TemaM), Linköping University, Linköping 58183, Sweden
| | - Qinghua Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yong Liang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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Liu J, Peng J, Yang J, Wang J, Peng X, Yan W, Zhao L, Peng L, Zhou Y. Comparative Analysis of the Physicochemical Properties and Metabolites of Farinose and Crisp Lotus Roots ( Nelumbo nucifera Gaertn.) with Different Geographical Origins. Foods 2023; 12:2493. [PMID: 37444231 DOI: 10.3390/foods12132493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/18/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023] Open
Abstract
Lotus roots are widely consumed vegetables because of their great taste and abundant nutrients, but their quality varies with the environments and cultivar. This study systematically compared farinose (Elian No. 5) and crisp (Elian No. 6) lotus root cultivars from three geographical origins. Pasting and texture characteristics verified that Elian No. 5 possessed lower hardness and lower ability to withstand shear stress and heating during cooking compared with Elian No. 6. Untargeted metabolite profiling was first performed using ultrahigh-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) combined with a Zeno trap. In total, 188 metabolites were identified based on the matching chemistry database. Multivariate analysis demonstrated that lotus roots from different cultivars and origins could be adequately distinguished. Sixty-one differential metabolites were identified among three Elian No. 5 samples, and 28 were identified among three Elian No. 6 samples. Isoscopoletin, scopoletin, and paprazine were the most differential metabolites between Elian No. 5 and Elian No. 6. These results can inform future research on the discrimination and utilization of lotus roots.
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Affiliation(s)
- Jiao Liu
- Hubei Key Laboratory of Nutritional Quality and Safety of Agro-Products, Institute of Quality Standard and Testing Technology for Agro-Products, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Jiawen Peng
- Hubei International Scientific and Technological Cooperation Base of Traditional Fermented Foods, College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jie Yang
- Hubei Key Laboratory of Nutritional Quality and Safety of Agro-Products, Institute of Quality Standard and Testing Technology for Agro-Products, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Jing Wang
- Hubei Key Laboratory of Nutritional Quality and Safety of Agro-Products, Institute of Quality Standard and Testing Technology for Agro-Products, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Xitian Peng
- Hubei Key Laboratory of Nutritional Quality and Safety of Agro-Products, Institute of Quality Standard and Testing Technology for Agro-Products, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Wei Yan
- Hubei Key Laboratory of Nutritional Quality and Safety of Agro-Products, Institute of Quality Standard and Testing Technology for Agro-Products, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | | | - Lijun Peng
- Hubei Key Laboratory of Nutritional Quality and Safety of Agro-Products, Institute of Quality Standard and Testing Technology for Agro-Products, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Youxiang Zhou
- Hubei Key Laboratory of Nutritional Quality and Safety of Agro-Products, Institute of Quality Standard and Testing Technology for Agro-Products, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
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Li Q, Li X, Ren Z, Du M, Yang J, Yang L, He W, Yang H, Zhao Y, Gu W, Liu W, Zhao W, Li Y. In-silico analysis of atmospheric diffusion, crop planting degrading scheme, and health risk of dioxins from a domestic waste incineration plant. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 160:59-68. [PMID: 36791511 DOI: 10.1016/j.wasman.2023.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
Based on a domestic waste incineration power generation project, the dioxin emission from the waste incineration plant (WIP), phytoextraction and microbial degradation of dioxins, and dioxins human health risks reduction were investigated through in-silico methods. Based on the dioxins concentrations in soil (9.97 × 10-9-7.00 × 10-5ng/g) predicted by atmospheric dispersion model system and the Level-III fugacity model, planting schemes under different wind directions were designed considering the dioxin absorption capacity and the economic benefits for crops (i.e., barley, peanut, pea, maize and wheat). The dioxins in soils can be further degraded by five crops' rhizosphere microorganisms and fertilizers, simulated through molecular dynamic simulations. The enhanced degradation rates of dioxin by rhizosphere microorganisms of five crops reached 15.70 %-28.66 %. Finally, healthy dietary plans were developed to reduce the risk of dioxin exposure to the sensitive populations living around WIP. Results showed that the consumption of maize, fungus, mushroom and bamboo fungus could effectively reduce dioxins toxicity to humans by 58.13 %. The systematic approach developed in this study provided theoretical support for soil remediation and human health risk control of dioxins-contaminated sites.
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Affiliation(s)
- Qing Li
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Xixi Li
- Center for Environmental Health Risk Assessment and Research, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Northern Region Persistent Organic Pollution Control (NRPOP) Laboratory, Faculty of Engineering and Applied Science, Memorial University, St. John's, NL A1B 3X5, Canada.
| | - Zhixing Ren
- College of Forestry, Northeast Forestry University, Harbin 150040, China.
| | - Meijn Du
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Jiawen Yang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Luze Yang
- College of New Energy and Environment, Jilin University, Changchun 130012, China.
| | - Wei He
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Hao Yang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Yuanyuan Zhao
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Wenwen Gu
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Wei Liu
- School of Environment, Beijing Normal University, 100875, China.
| | - Wenjin Zhao
- College of New Energy and Environment, Jilin University, Changchun 130012, China.
| | - Yu Li
- College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
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Yu M, Chen L, Tao H, Cao M, Zhang X, Liang Y, Shi J. Pollution status and risk assessment of heavy metals in the sediment of a historically contaminated lake treated by oxidation pond in China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:41794-41805. [PMID: 36639589 DOI: 10.1007/s11356-023-25205-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 01/04/2023] [Indexed: 01/15/2023]
Abstract
Sediment plays an important role in controlling biogeochemical cycling of heavy metals in aquatic environment. The Ya-Er Lake is a typical lake which was historically contaminated by heavy metals in Hubei province, China. After industries surrounding the Ya-Er Lake being shut down, oxidation pond treatment and dredging program were conducted for pollution management since 1970s. To date, the Ya-Er Lake has been used for aquaculture for several decades. However, the status of heavy metal levels and ecological risks in this lake remains unclear. Herein, concentrations, chemical fractions, and risk assessment of heavy metals were investigated in the Ya-Er Lake sediment. Results showed that concentrations of heavy metals in the Ya-Er Lake sediment were higher than other reported lake systems, suggesting that heavy metal pollution in the Ya-Er Lake is still serious. Relatively higher proportions of carbonates bound form of Cd and Ni indicated high-risk potential of these two heavy metals, and Cd and Ni should be listed as the primary heavy metal pollutants in the Ya-Er Lake according to the results of potential ecological risk index (PERI) and sediment quality guidelines (SQGs). The risk assessment code (RAC) analysis showed that Ni and Cd poses higher bioavailability and mitigation potential, and may affect the Ya-Er Lake ecosystem and downstream aquatic environment. These findings reflected that oxidation pond treatment and dredging sediment to near place are not effective to control heavy metal pollution, and a long-term ecological risk is still posed to surrounding aquatic environment. Our study provides scientific basis on pollution control and management in aquatic system contaminated by heavy metals.
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Affiliation(s)
- Mingyue Yu
- State Key Laboratory of Precision Blasting, Jianghan University, Wuhan, 430056, China
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan, 430056, China
| | - Lufeng Chen
- State Key Laboratory of Precision Blasting, Jianghan University, Wuhan, 430056, China
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan, 430056, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Hui Tao
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan, 430056, China
| | - Mengxi Cao
- State Key Laboratory of Precision Blasting, Jianghan University, Wuhan, 430056, China
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan, 430056, China
| | - Xing Zhang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan, 430056, China.
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Science, Northwest University, Xi'an, 710127, China.
| | - Yong Liang
- State Key Laboratory of Precision Blasting, Jianghan University, Wuhan, 430056, China
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan, 430056, China
| | - Jianbo Shi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
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Assessment of Distribution of Potentially Toxic Elements in Different Environmental Media Impacted by a Former Chlor-Alkali Plant. SUSTAINABILITY 2021. [DOI: 10.3390/su132413829] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Former industrially contaminated sites are a burden from the past that still pose environmental risks. During the second half of the 20th century, the Pavlodar region in North Kazakhstan had been a part of Soviet Union’s industrial system that operated a chlor-alkali plant (CAP). The former CAP discharged approximately 135 t Hg into nearby Lake Balkyldak with total losses to water, soil, and air estimated around 1000 t. Pollution by potentially toxic elements (PTEs) due to former and currently active industrial enterprises is an under-investigated concern in the Pavlodar region. The present study aims to provide a much-needed update on the situation around the CAP area by evaluating the contamination by Hg and other selected PTEs (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Zn) on the surrounding environment of the CAP and in the nearby urban zone. Soil, sediment, surface water, and groundwater samples have been collected in several sampling campaigns carried out in 2018 and 2019. Several samples had Hg concentrations exceeding maximum permissible concentrations (MPC), for soils and sediments (in mg/kg; range: 0.0006 to 24, average: 0.56) and for surface water and groundwater (in µg/L; range: 0.004 to 1340, average: 93). Critically high concentrations were mostly measured in the vicinity of Lake Balkyldak, where the majority of Hg had been discharged by the former CAP, indicating persisting Hg pollution in the studied zone. A comparison of the PTEs concentrations in soil and sediments showed less severe pollution but still some elevated values for As, Ba, Co, Cu, Mn, Ni, and Se. The inter-elemental relationship between Hg and assessed PTEs was weak, indicating the presence of sources independent from Hg emitting sources. Further research on Hg contamination on the exact territory of the former CAP is needed, and a detailed human health risk characterization to identify potential unacceptable risks is strongly recommended.
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