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Pu T, Kong Y, Kang S, Wang S, Guo J, Jia J, Wu K, Shi X, Wang K, Sun S, Li W. Mercury export from a glacier-fed river of Mt. Meili, southeastern Tibetan Plateau. JOURNAL OF HAZARDOUS MATERIALS 2024; 477:135306. [PMID: 39067291 DOI: 10.1016/j.jhazmat.2024.135306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 07/10/2024] [Accepted: 07/21/2024] [Indexed: 07/30/2024]
Abstract
Mercury (Hg), a global contaminant, can sink into cryosphere and be released into runoff through meltwater. The Tibetan Plateau (TP) has been witnessing ongoing shrinkage of alpine glaciers. However, the export of Hg from melting glacier is still sparsely reported. From October 16, 2020 to October 15, 2021, we conducted daily observations to study the variation in total Hg concentrations and its export to the Mingyong River, a glacier-fed river in southeastern TP. Results showed that the Hg concentrations were high during the monsoon season but low during the non-monsoon period. The Hg in runoff correlated with the concentrations of total suspended particulates (TSP) and dissolved inorganic carbon (DIC) during both monsoon and non-monsoon seasons (p < 0.01), and the correlation of Hg with other parameters showed seasonal variations. The input from meltwater, precipitation, and groundwater to riverine Hg were 8.3 g, 264.4 g, and 71.0 g, respectively, and the total export was 211.0 g (yield: 4.3 g/km2/year) in the hydrological year, indicating that Mingyong catchment act as a sink for Hg. For the entire TP, the annual export of Hg from glacier runoff was estimated to be 947.7 kg/year. Our study highlights the necessity for further investigations on Hg dynamics to understand the changes in the Hg cycle within glaciated aquatic ecosystems.
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Affiliation(s)
- Tao Pu
- Yulong Snow Mountain Cryosphere and Sustainable Development Field Science Observation and Research Station/Key Laboratory of Cryospheric Sciences and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
| | - Yanlong Kong
- Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.
| | - Shichang Kang
- Yulong Snow Mountain Cryosphere and Sustainable Development Field Science Observation and Research Station/Key Laboratory of Cryospheric Sciences and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Shijin Wang
- Yulong Snow Mountain Cryosphere and Sustainable Development Field Science Observation and Research Station/Key Laboratory of Cryospheric Sciences and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Junming Guo
- Yulong Snow Mountain Cryosphere and Sustainable Development Field Science Observation and Research Station/Key Laboratory of Cryospheric Sciences and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Jia Jia
- College of Geography and Environment Sciences, Zhejiang Normal University, Jinhua 321000, China
| | - Kunpeng Wu
- Yunnan University, Kunming 650000, China
| | - Xiaoyi Shi
- College of Geography and Environment Sciences, Zhejiang Normal University, Jinhua 321000, China
| | - Ke Wang
- Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Shiwei Sun
- Yulong Snow Mountain Cryosphere and Sustainable Development Field Science Observation and Research Station/Key Laboratory of Cryospheric Sciences and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Wenjie Li
- China University of Mining & Technology, Beijing, Beijing 100029, China
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Li R, Yan J, Wang C, Yang S, Zhang L, Peng T, Zhu W, Li P, Zhang L, Feng X. Mercury sources, transport, and transformation in rainfall-runoff processes: Mercury isotope approach. WATER RESEARCH 2024; 261:122044. [PMID: 38972237 DOI: 10.1016/j.watres.2024.122044] [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: 03/21/2024] [Revised: 06/25/2024] [Accepted: 07/02/2024] [Indexed: 07/09/2024]
Abstract
Mercury (Hg) in runoff water poses significant ecological risks to aquatic ecosystems that can affect organisms. However, accurately identifying the sources and transformation processes of Hg in runoff water is challenging due to complex natural conditions. This study provides a comprehensive investigation of Hg dynamics in water from rainfall to runoff. The Hg isotope fractionation in water was characterized, which allows accurate quantification of Hg sources, transport, and transformations in rainfall-runoff processes. Δ200Hg and corrected Δ199Hg values can serve as reliable tracers for identifying Hg sources in the runoff water and the variation of δ202Hg can be explained by Hg transformation processes. During runoff migration processes, Hg from rainfall is rapidly absorbed on the land surface, while terrestrial Hg entering the water by the dissolution process becomes the primary component of dissolved mercury (DHg). Besides the dissolution and adsorption, microbial Hg(II) reduction and demethylation of MeHg were dominant processes for DHg in the runoff water that flows through the rice paddies, while photochemical Hg(II) reduction was the dominant process for DHg in the runoff water with low water exchange rates. Particulate Hg (PHg) in runoff water is dominantly originated by the terrestrial material and derived from the dissolution and adsorption process. Tracking sources and transformations of Hg in runoff water during the rainfall-runoff process provides a basis for studying Hg pollution in larger water bodies under complex environmental factors.
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Affiliation(s)
- Ruolan Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junyao Yan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chuan Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shaochen Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Lin Zhang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Puding Karst Ecosystem Research Station, Chinese Academy of Sciences, Puding 562100, China
| | - Tao Peng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Puding Karst Ecosystem Research Station, Chinese Academy of Sciences, Puding 562100, China
| | - Wei Zhu
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå SE-90183, Sweden
| | - Ping Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Leiming Zhang
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto M3H5T4, Canada
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Cai S, Shen Z, Zhou S, Wang Q, Cheng J, Yan X, Tan M, Tu G, Cen Y. Health risk assessment and potential sources of metals in riparian soils of the Wujiang River, China. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2024; 46:106. [PMID: 38446315 DOI: 10.1007/s10653-024-01919-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 02/15/2024] [Indexed: 03/07/2024]
Abstract
In order to understand the pollution status of metals in the riparian soils along the Wujiang River, 26 sampling sites in the mainstream and tributary streams were selected for investigation. The geo-accumulation index (Igeo), Nemerow integrated pollution index, and potential ecological risk index were applied to evaluate the contamination status and ecological risks of metals. Results revealed that the average concentrations of As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn were 12.20, 0.51, 84.01, 57.42, 922.57, 38.37, 38.06, and 127.82 mg/kg, respectively. The metal contamination degree and ecological risks in the upper reaches were significantly higher than those in the middle and lower reaches of the Wujiang River. Cd was the dominant contamination metal. Significant non-carcinogenic and carcinogenic risks of metals were found in children based on the hazard index and carcinogenic risk. As was the main non-carcinogenic and carcinogenic pollutant metal in both adults and children. According to principal component analysis, hierarchical clustering analysis, and absolute principal component scores-multiple linear regression, anthropogenic sources (mining and agricultural activities) contributed most to Zn, Pb, Cr, Cd, Cu, and Ni, with contribution rates of 89.14, 82.32, 74.46, 72.12, 68.52, and 61.02%, respectively. Natural sources contributed most to Mn, with a contribution rate of 83.07%. Unidentified sources contributed most to As, with a contribution rate of 47.27%.
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Affiliation(s)
- Shenwen Cai
- College of Resources and Environment, Zunyi Normal University, Zunyi, China.
| | - Ziwei Shen
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Shaoqi Zhou
- College of Resources and Environment Engineering, Guizhou University, Guiyang, China
| | - Qinghe Wang
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Junwei Cheng
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Xiong Yan
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Mingjie Tan
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Guojing Tu
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Yi Cen
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
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Zhang X, Kang H, Zhao L, Guo J, Zhang Y, Xie C, Dong X, Kang S, Liu X. Climate and industrial pollution determine the seasonal and spatial mercury variations in the China's Weihe River. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168555. [PMID: 37979855 DOI: 10.1016/j.scitotenv.2023.168555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/23/2023] [Accepted: 11/11/2023] [Indexed: 11/20/2023]
Abstract
Natural processes and human activities impact mercury (Hg) pollution in rivers. Investigating the individual contributions and interactions of factors affecting variations in Hg concentrations, particularly under climate change, is crucial for safeguarding watershed ecosystems and human health. We collected 381 water samples from China's Weihe River Basin (WRB) during dry and wet seasons to assess the total Hg (THg) concentration. Results revealed high Hg concentrations in the WRB (0.1-2200.9 ng/L, mean 126.2 ± 335.5 ng/L), with higher levels during the wet season (wet season: 249.1 ± 453.5 ng/L, dry season: 12.7 ± 14.0 ng/L), particularly in the mainstream and southern tributaries of the Weihe River. Industrial pollution (contributing 26.2 %) and precipitation (contributing 33.5 %) drove spatial heterogeneity in THg concentrations during the dry and wet seasons, respectively. Notably, combined explanatory power increased to 47.9 % when interaction was considered, highlighting the amplifying effect of climate change, particularly precipitation, on the impact of industrial pollution. The middle and downstream of the Weihe River, especially the Guanzhong urban agglomeration, were identified as high-risk regions for Hg pollution. With ongoing climate change the risk of Hg exposure in the WRB is expected to escalate. This study lays a robust scientific foundation for the effective management of Hg pollution in analogous river systems worldwide.
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Affiliation(s)
- Xinyu Zhang
- School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China
| | - Huhu Kang
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Liangju Zhao
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710069, China
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Yu Zhang
- School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China; State Environmental Protection Key Laboratory of Urban Ecological Environment Simulation and Protection, South China Institute of Environmental Sciences, MEE, Guangzhou 510530, China
| | - Cong Xie
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710069, China
| | - Xiying Dong
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710069, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaohong Liu
- School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China; State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
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Cai S, Shen Z, Wang Q, Cheng J, Yan X, Zeng B. Bioaccumulation and Health Risk Assessment of Metals in Small-Sized Fish (Rhodeus sinensis, Ctenogobius giurinus) and Mussel (Cristaria plicata) from a River Reservoir, Southwest China. Biol Trace Elem Res 2023; 201:5401-5414. [PMID: 36753037 DOI: 10.1007/s12011-023-03590-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 01/31/2023] [Indexed: 02/09/2023]
Abstract
In order to assess the bioaccumulation and health risk of metals in a river reservoir, concentrations of copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in the water, sediments, two small-sized fish, and a freshwater mussel from the Zhoubai reservoir were examined. The results indicated that all of these metals conform with class one of environmental quality standards for surface water (State Environmental Protection Administration of China, GB 3838-2002). There were no significant differences for total metal concentrations in sediment between the three sampling sites (p > 0.05), but the bioavailable concentrations in S3 were the lowest. The Cd was dominated with exchangeable fraction and showed considerable risk. All metal concentrations except for Pb in Rhodeus sinensis were significantly higher than those in Ctenogobius giurinus (p < 0.05). The metal concentrations in Cristaria plicata showed a similar pattern of bioavailable metals in sediment, indicating that the metal concentrations in aquatic organisms were determined by the bioavailable forms of metals. Negative correlations were observed between the size of fish and concentrations of Cu, Zn, Pb, Cd, and As. However, significant positive correlations were found between the size of mussel and concentrations of Cd (p < 0.01), As (p < 0.05), and Hg (p < 0.01). Zn had the highest BCF values in fish and mussel. The aquatic organisms showed lower ability of metal bioaccumulation from the sediment. Low values of target hazard quotient (THQ), hazard index (HI), and carcinogenic risk (CR) indicated that these metals do not pose a health risk to public through fish and mussel consumption in this study area.
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Affiliation(s)
- Shenwen Cai
- College of Resources and Environment, Zunyi Normal University, Zunyi, China.
| | - Ziwei Shen
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Qinghe Wang
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Junwei Cheng
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Xiong Yan
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Boping Zeng
- College of Biology and Agriculture, Zunyi Normal University, Zunyi, China
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Cai S, Zhou S, Yan X, Xiao Y, Cheng J, Wang Q, Zeng B. Comparative study on metal concentrations in water, sediments, and two fish species (Cyprinus carpio and Pelteobagrus fulvidraco) from the Wujiang River, China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:44845-44860. [PMID: 36701068 DOI: 10.1007/s11356-023-25533-4] [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: 09/11/2022] [Accepted: 01/19/2023] [Indexed: 06/17/2023]
Abstract
In order to assess the metal pollution in the Wujiang River, concentrations of Cu, Zn, Fe, Mn, Pb, Cd, As, and Hg in the water, sediments, and two fish species Cyprinus carpio and Pelteobagrus fulvidraco from the middle reaches (Tuomugang, TMG) and lower reaches (Wulong, WL) of the Wujiang River were examined. The results indicated that all metal concentrations were lower than the values for grade one water quality according to the Environment Quality Standard for Surface Water of China (GB 3838-2002). The bioavailable fraction concentrations of Zn, Fe, Mn, Pb, and Hg in WL were significantly higher than those in TMG (p < 0.05), indicating that these metals in sediments of WL have higher bioavailability and mobility. The Cu, Zn, Fe, Pb, As, and Hg were mainly related to the residual fraction, while the Mn and Cd were mainly associated with the non-residual fraction. The risk assessment code (RAC) and the secondary phase to the primary phase (RSP) values indicated that Mn and Cd have a high risk of secondary release. The mean metal concentrations in the liver of the two fish species were higher than those in muscle. The higher metal concentrations of fish in WL suggested that bioaccumulation of metals in fish could be influenced by metal bioavailability. No identical relationships between metal concentrations and fish length were manifested in the present study. The values of target hazard quotient (THQ) and hazard index (HI), and carcinogenic risk (CR) of metals for the consumption of C. carpio and P. fulvidraco indicated that the anglers would likely not experience significant non-carcinogenic risk, but the carcinogenic risk of As cannot be ignored. Thanks to prohibited commercial fishing in the Wujiang River, the metal pollution will probably not pose a health risk to the general public for wild fish consumption.
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Affiliation(s)
- Shenwen Cai
- College of Resources and Environment, Zunyi Normal University, Zunyi, China.
| | - Shaoqi Zhou
- College of Resources and Environment Engineering, Guizhou University, Guiyang, China
| | - Xiong Yan
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Ye Xiao
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Junwei Cheng
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Qinghe Wang
- College of Resources and Environment, Zunyi Normal University, Zunyi, China
| | - Boping Zeng
- College of Biology and Agriculture, Zunyi Normal University, Zunyi, China
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Branco JM, Hingst-Zaher E, Jordan-Ward R, Dillon D, Siegrist J, Fischer JD, Schiesari L, von Hippel FA, Buck CL. Interrelationships among feather mercury content, body condition and feather corticosterone in a Neotropical migratory bird, the Purple Martin (Progne subis subis). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120284. [PMID: 36206890 DOI: 10.1016/j.envpol.2022.120284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 09/09/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Purple Martins (Progne subis) are migratory birds that breed in North America and overwinter and complete their molt in South America. Many of the breeding populations are declining. The eastern North American subspecies of Purple Martin (P. subis subis) comprises >90% of all Purple Martins. This subspecies overwinters and molts in the Amazon Basin, a region that is high in mercury (Hg) contamination, which raises the possibility that observed declines in Purple Martins could be linked to Hg exposure. Exposure to Hg results in numerous and systemic negative health outcomes, including endocrine disruption. Corticosterone (CORT) is a primary modulator of the stress and metabolic axes of vertebrates; thus, it is important in meeting metabolic and other challenges of migration. Because feathers accumulate Hg and hormones while growing, quantification of Hg and CORT in feathers provides an opportunity to retrospectively assess Hg exposure and adrenal activity of birds using minimally invasive methods. We evaluated interrelationships among concentrations of total Hg (THg) and CORT in feathers that grew in the Amazon Basin and body condition (mass, fat score) of these birds in North America. Concentrations of THg in Purple Martin feathers ranged from 1.103 to 8.740 μg/g dw, levels associated with negative physiological impacts in other avian species. Concentrations of CORT did not correlate with THg concentration at the time of feather growth. However, we found evidence that THg concentration may negatively impact the ability of Purple Martins to accumulate fat, which could impair migratory performance and survivorship due to the high energy requirements of migration. This finding suggests potential carryover effects of Hg contamination at the wintering grounds in the Amazon to the summer breeding grounds in North America.
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Affiliation(s)
- Jonathan M Branco
- Departmento de Ecologia, Universidade de São Paulo, Rua do Matao, 321 - Trav. 14, São Paulo, CEP 05508090, Brazil.
| | - Erika Hingst-Zaher
- Museu Biologico, Instituto Butantan - Av Vital Brasil 1500, São Paulo, CEP 05503-900, Brazil
| | - Renee Jordan-Ward
- Department of Biological Sciences, Northern Arizona University - 617 S Beaver, Flagstaff, AZ, 86011, USA
| | - Danielle Dillon
- Department of Biological Sciences, Northern Arizona University - 617 S Beaver, Flagstaff, AZ, 86011, USA
| | - Joe Siegrist
- Purple Martin Conservation Association - 301 Peninsula Drive, Suite 6 Erie, PA, 16505, USA
| | - Jason D Fischer
- Disney's Animals, Science and Environment, Lake Buena Vista, FL, 32830, USA
| | - Luis Schiesari
- Escola de Artes, Ciências e Humanidades, Universidade de São Paulo - Rua Arlindo Bettio, 1000, São Paulo, CEP 03828-000, Brazil
| | - Frank A von Hippel
- Department of Community, Environment and Policy, University of Arizona - 1295 N. Martin Avenue, Tucson, AZ, 85724, USA
| | - C Loren Buck
- Department of Biological Sciences, Northern Arizona University - 617 S Beaver, Flagstaff, AZ, 86011, USA
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He K, Wang J, Chen Q, Wu F, Yang X, Chen J. Effects of cascade dams on the occurrence and distribution of microplastics in surface sediments of Wujiang river basin, Southwestern China. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 240:113715. [PMID: 35659701 DOI: 10.1016/j.ecoenv.2022.113715] [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: 11/22/2021] [Revised: 05/23/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
The influence of cascade dams on the migration of microplastics (MPs) was conducted by analyzing the spatial distribution of MPs in sediments of the Wujiang river basin (Wujiang river basin) in Southwest China. The results showed that the abundance of MPs in Wujiang river basin sediments ranged from 310 to 2620 items/kg dw (mean: 1354 items/kg dw, a high level compared with aquatic sediments worldwide). The main chemical components of these MPs were polypropylene and polyethylene. High abundance of MPs in tributary sediments suggested that tributary inputs contributed to the main stream and reservoirs. Statistical analysis showed that gross domestic product (GDP) and the basin area of cascade reservoirs, rather than hydraulic retention time and reservoir age, were the dominating factors in the distribution of MPs in the Wujiang river basin. The accumulation of MPs in cascade reservoirs implied the interception effect of cascade dams. The rapid development of cascade dam systems and the interception effect of dams should be taken into account when predicting the flux of MPs from rivers to the ocean. Heavy metals found on the surface of the MPs showed the compound pollution of MPs and heavy metals in dammed rivers and cascade reservoirs. Our results deepen the understanding of the migration of MPs in rivers alongside intensive cascade hydropower development.
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Affiliation(s)
- Kangkang He
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, PR China
| | - Jingfu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Quan Chen
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Fengxue Wu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, PR China
| | - Xiaohong Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, PR China
| | - Jingan Chen
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
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9
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Ma H, Chen Y, Chen Q, Liu D, Zhang J, Tonina D. Dam cascade unveils sediment methylmercury dynamics in reservoirs. WATER RESEARCH 2022; 212:118059. [PMID: 35124561 DOI: 10.1016/j.watres.2022.118059] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 12/21/2021] [Accepted: 01/09/2022] [Indexed: 06/14/2023]
Abstract
Methylmercury (MeHg) can be bioaccumulated through food chains and adversely affect human health. Reservoirs are reported to stimulate MeHg production, however, the characteristics of MeHg dynamics in cascade reservoirs and the associated relations to sedimentation as well as reservoir properties remained unclear. Here we investigated sediment MeHg dynamics in eight cascade reservoirs in the upper Mekong River. We found significant differences in sediment MeHg concentration between the reservoirs, showing an increase with fluctuations along the reservoirs cascade. However, a novel relationship was found between sediment%MeHg (MeHg/Hg) and the ratio of reservoir hydraulic residence time (HRT) to reservoir age. This relationship is formed by the joint effects of the original deposit of Hg and organic carbon (OC) before impoundment and the subsequent sedimentation of Hg and OC after impoundment. The original deposit is continuously transformed as the reservoir ages, whereas the latter is driven by the annual hydrological cycle and HRT, of which the HRT is dominant. This finding cannot be easily revealed in a single reservoir or by comparing multiple reservoirs in different rivers. The discovery is of great significance to understand Hg geochemical cycling in reservoirs, which is quickly increasing in rivers worldwide.
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Affiliation(s)
- Honghai Ma
- State Key Laboratory of Hydrology-Water Resources & Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, 210029, China; Center for Eco-Environmental Research, Nanjing Hydraulic Research Institute, Nanjing 210029, China
| | - Yuchen Chen
- Center for Eco-Environmental Research, Nanjing Hydraulic Research Institute, Nanjing 210029, China
| | - Qiuwen Chen
- State Key Laboratory of Hydrology-Water Resources & Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, 210029, China; Yangtze Institute for Conservation and Green Development, Nanjing, 210029, China; Center for Eco-Environmental Research, Nanjing Hydraulic Research Institute, Nanjing 210029, China.
| | - Dongsheng Liu
- Center for Eco-Environmental Research, Nanjing Hydraulic Research Institute, Nanjing 210029, China
| | - Jianyun Zhang
- State Key Laboratory of Hydrology-Water Resources & Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, 210029, China; Yangtze Institute for Conservation and Green Development, Nanjing, 210029, China.
| | - Daniele Tonina
- Center for Ecohydraulics Research, University of Idaho, Boise, ID, 83702, USA
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Jung E, Kim H, Yun D, Rahman MM, Lee JH, Kim S, Kim CK, Han S. Importance of hydraulic residence time for methylmercury accumulation in sediment and fish from artificial reservoirs. CHEMOSPHERE 2022; 293:133545. [PMID: 34998844 DOI: 10.1016/j.chemosphere.2022.133545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 12/30/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
Excessive methylmercury (MeHg) accumulation in dietary fish is a global concern due to its harmful effects on human health, however, environmental factors affecting MeHg accumulation in reservoir ecosystems are not clearly known. In this study, we aim to identify the main sources of MeHg in the water column and the critical factors related to MeHg concentration and methylation rate constant (km) in sediment and total Hg concentration in fish using five-year (2016-2020) monitoring data of the five artificial reservoirs. The preliminary mass budgets constructed using the measurement and online data showed that sediment transport dominated over runoff in the long residence time reservoirs (400-475 days), while runoff dominated over sediment transport in the short residence time reservoirs (10 days). Whereas the sediment km showed a comparable variation with the algal biomass, the sediment MeHg concentration and the length-normalized Hg concentration in the barbel steed and bluegill increased in the longer residence time reservoirs with lower algal biomass. As MeHg accumulation in sediment and fish tends to increase in the slowly overturning reservoirs, the hydraulic residence time should be carefully managed to meet the best protection of human health from chronic Hg exposure by fish consumption.
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Affiliation(s)
- Eunji Jung
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Hyogyeong Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Daseul Yun
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Md Moklesur Rahman
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Jong-Hyeon Lee
- Environmental Human Research & Consulting (EHR&C), Incheon, 22689, Republic of Korea
| | - Suhyun Kim
- Environmental Human Research & Consulting (EHR&C), Incheon, 22689, Republic of Korea
| | - Chan-Kook Kim
- Marine Environment Research Institute, OCEANIC C&T Co., Ltd, Kangwon, 25601, Republic of Korea
| | - Seunghee Han
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea.
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11
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He K, Wang J, Liao P, Sun Q, Yang X, Jin Z, Chen J. Effects of cascade dam on the distribution of heavy metals and biogenic elements in sediments at the watershed scale, Southwest China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:8970-8979. [PMID: 34494191 DOI: 10.1007/s11356-021-16363-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 09/01/2021] [Indexed: 06/13/2023]
Abstract
Cascade dam has important effects on the magnitude and dynamics of sediment particles, heavy metals, and biogenic elements in reservoirs. However, systematic studies on the interception effect of cascade dam on the various elements that occur in rivers at the watershed scale are lacking. The aims of this study were to (1) assess the interception effect of a cascade dam on heavy metals and biogenic elements and (2) investigate the key factors of these effects of the cascade dam. Surface sediments were collected from 29 sites distributed in the Wujiang River Basin (WRB, a watershed scale in Southwest China), including from tributaries (7 sites), the main stream (13 sites), and cascade reservoirs (9 sites). In addition, the particle sizes, heavy metals (Fe, Mn, Zn, Cr, Cu, As, Pb, and Cd), and biogenic elements (TOC, TN, and TP) of sediments were analyzed. Compared with the tributaries, D50 (median particle size) was significantly reduced by 56.8% of cascade reservoirs. The proportion of 63-2,000 μm decreased from 13.78 to 1.34%, indicating that more coarse particles were intercepted in the cascade reservoirs. The contents of heavy metals (Fe, Zn, Cu, As, and Cd) declined significantly along the way. On the whole, the contents of TOC, TN, and TP were highest in the midstream and lower in the upstream and downstream. The hydrological condition (reservoir age, HRT, and flow) and the basin area and internal and external inputs of cascade reservoirs are important factors. The findings deepen the current understanding of the mechanisms by which cascade dam affects the river transport of heavy metals and biogenic elements at the watershed scale and provide an important reference for establishing hydropower developments along rivers and developing aquatic environment management strategies.
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Affiliation(s)
- Kangkang He
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, People's Republic of China
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
| | - Jingfu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China.
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
| | - Peng Liao
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Qingqing Sun
- Institute of Surface Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, People's Republic of China
| | - Xiaohong Yang
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, People's Republic of China
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
| | - Zuxue Jin
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Jingan Chen
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China.
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
- CAS Center for Excellence in Quaternary Science and Global Change, Xi'an, 710061, People's Republic of China.
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12
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Analysis of Runoff Variation Characteristics and Influencing Factors in the Wujiang River Basin in the Past 30 Years. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 19:ijerph19010372. [PMID: 35010631 PMCID: PMC8750757 DOI: 10.3390/ijerph19010372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/10/2021] [Accepted: 12/21/2021] [Indexed: 11/17/2022]
Abstract
Changes in climate and the underlying surface are the main factors affecting runoff. Quantitative assessment of runoff characteristics, and determination of the climate and underlying surface contribution to changes in runoff are critical to water resources management and protection. Based on the runoff data from the Wulong Hydrological Station, combined with the Mann-Kendall test, Indicators of Hydrologic Alteration (IHA), Budyko hypothesis, and changes in climate and the underlying surface, this study comprehensively analyzed the runoff in the Wujiang River Basin (WRB). The results showed that: (1) The annual runoff of Wujiang River showed a downward trend, and an abrupt change occurred in 2005. (2) The overall hydrological change in WRB is 46%, reaching a moderate change. (3) The contribution rates of precipitation (P), potential evaporation (ET0), and underlying surface to runoff changes are 61.5%, 11.4%, and 26.9%, respectively. (4) After 2005, the WRB has become more arid, human activities have become more active, vegetation coverage has increased, and the built-up land has increased significantly.
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13
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Ni FJ, Bhavsar SP, Poirier D, Branfireun B, Petro S, Arts MT, Chong-Kit R, Mitchell CPJ, Arhonditsis GB. Impacts of water level fluctuations on mercury concentrations in hydropower reservoirs: A microcosm experiment. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 220:112354. [PMID: 34116335 DOI: 10.1016/j.ecoenv.2021.112354] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 04/02/2021] [Accepted: 05/15/2021] [Indexed: 06/12/2023]
Abstract
Hydropower generation, a renewable source of electricity, has been linked to elevated methylmercury (MeHg) concentrations in impoundments and aquatic biota. This study investigates the impact of water level fluctuations (WLF) on MeHg concentrations in water, sediment, and fish. Using a set of controlled microcosm experiments emulating the drawdown/refill dynamics and subsequent sediment exposure to air experienced in reservoirs, we demonstrate that less frequent WLFs, and/or increased exposure of sediment to air, can lead to elevated MeHg concentrations in sediment, and total mercury (THg) and MeHg concentrations in water. In examining the effects of WLF frequency (two-day, weekly, and monthly), the monthly treatment displayed the highest THg and MeHg water levels, while the weekly treatment was characterized by the highest MeHg levels in the sediment. Our work supports emerging evidence that longer duration between WLF creates a larger surface area of sediment exposed to air leading to conditions conducive to higher MeHg concentrations in sediments and water. In contrast, THg, MeHg, and fatty acid trends in fish were largely inconclusive characterized by similar among-treatment effects and minimal temporal variability over the course of our experiment. This result could partly be attributed to overall low mercury levels and simple "worm-forage fish" food web in our experiment. To elucidate the broader impacts of water fluctuations on aquatic chemistry and biota, other factors (e.g., longer WLF cycles, dissolved organic matter, temperature, more complex food webs) which modulate both methylation rates and food web dynamics must be considered.
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Affiliation(s)
- Felicity J Ni
- Department of Physical & Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Satyendra P Bhavsar
- Department of Physical & Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada; Ontario Ministry of Environment, Conservation, and Parks, Toronto, Ontario M9P 3V6, Canada.
| | - David Poirier
- Ontario Ministry of Environment, Conservation, and Parks, Toronto, Ontario M9P 3V6, Canada
| | - Brian Branfireun
- Department of Biology and Centre for Environment & Sustainability, Western University, London, Ontario N6A 3K7, Canada
| | - Steve Petro
- Ontario Ministry of Environment, Conservation, and Parks, Toronto, Ontario M9P 3V6, Canada
| | - Michael T Arts
- Department of Chemistry & Biology, Ryerson University, Toronto, Ontario M5B 2K3, Canada
| | - Richard Chong-Kit
- Ontario Ministry of Environment, Conservation, and Parks, Toronto, Ontario M9P 3V6, Canada
| | - Carl P J Mitchell
- Department of Physical & Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - George B Arhonditsis
- Department of Physical & Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada.
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14
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Xie Q, Wang Y, Li S, Zhang C, Tian X, Cheng N, Zhang Y, Wang D. Total mercury and methylmercury in human hair and food: Implications for the exposure and health risk to residents in the Three Gorges Reservoir Region, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 282:117041. [PMID: 33838440 DOI: 10.1016/j.envpol.2021.117041] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/23/2021] [Accepted: 03/27/2021] [Indexed: 06/12/2023]
Abstract
Three Gorges Dam (TGD) is the largest hydroelectric construction in the world, and its potential impacts on the ecological environment and human health risks have invoked considerable global concern. However, as a mercury (Hg) sensitive system, limited work was conducted on the Hg exposure level of local residents around the Three Gorges Reservoir (TGR). Thus, 540 human hair samples and 22 species of local food samples were collected to assess the Hg exposure and human health risk to the residents located in the Three Gorges Reservoir Region (TGRR) and to investigate their dietary exposure to Hg. The results showed that the geometric mean concentrations of total mercury (THg) and methylmercury (MeHg) in hair were 0.42 ± 0.43 μg g-1 and 0.23 ± 0.32 μg g-1, respectively, lower than the reference level (1.0 μg g-1) recommended by the United States Environmental Protection Agency (US EPA), indicating a low level Hg exposure for residents around the TGR. No significant difference in the accumulation of Hg in hair between the gender subgroups was observed, whereas age difference, smoking and alcohol drinking behavior, and fish consumption frequency were significant predictors of hair Hg level. Besides, THg and MeHg of all the investigated food samples did not exceed the corresponding Chinese national standard. The average probable daily intakes (PDIs) of THg and MeHg were 0.032 μg kg-1 day-1 and 0.007 μg kg-1 day-1, which were obviously below the recommended values of 0.57 μg kg-1 day-1 and 0.1 μg kg-1 day-1, respectively. The cereal (mainly rice) contribution of THg (76.0%) and MeHg (74.4%) intakes to the local residents around the TGR was much higher than that of fish (10.7% and 22.9%, respectively) due to the considerable rice consumption. Overall, residents around the TGR were at a low Hg exposure and rice consumption was the major pathway for Hg exposure.
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Affiliation(s)
- Qing Xie
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Yongmin Wang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Shouying Li
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Cheng Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Xiaosong Tian
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Nan Cheng
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Yongjiang Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China; Department of Environment and Quality Test, Chongqing Chemical Industry Vocational College, Chongqing, 401220, China
| | - Dingyong Wang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing, 400715, China.
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15
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Zhu J, Tang L, Qiao S, Wang L, Feng Y, Wang L, Wu Q, Ding P, Zhang Z, Li L. Low-dose methylmercury exposure impairs the locomotor activity of zebrafish: Role of intestinal inositol metabolism. ENVIRONMENTAL RESEARCH 2020; 190:110020. [PMID: 32777273 DOI: 10.1016/j.envres.2020.110020] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/26/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
Methylmercury (MeHg) is a ubiquitous environmental toxicant with neurotoxic effects. Although its neurotoxicity had been more studied, the role of gut microbiota remains unclear. In this study, adult zebrafish and larvae were exposed to MeHgCl at the dose of 0, 1 and 10 ng/mL. MeHgCl exposure impaired the locomotor activity via upregulation of apoptosis and autophagy related genes in the brain. Intestinal and cerebral metabolome indicated that phosphatidylinositol signaling system and inositol phosphate metabolism pathways were significantly impacted in adult zebrafish upon MeHgCl exposure. The levels of myo-inositol (MI) in the intestine and brain were decreased and positively correlated. 16 S rRNA sequencing data from adult zebrafish showed that MeHgCl exposure also shifted the structure of gut microbiota and reduced the relative abundance of Bacteroidetes and Proteobacteria, which were further identified at genus level as Aeromonas and Cetobacterium. Further functional analysis indicated that MeHgCl disrupted inositol phosphate metabolism of gut microbiota. Notably, MI supplementation restored the impairment of locomotor activity and inhibited the upregulation of apoptosis and autophagy related genes, such as bcl-2 and atg5. Thus, this study not only revealed the key role of gut microbiota in MeHgCl-mediated neurotoxicity but also gave new insights into antagonizing its toxicity.
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Affiliation(s)
- Jun Zhu
- Center for Global Health, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China
| | - Lei Tang
- Center for Global Health, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China
| | - Shanlei Qiao
- Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China
| | - Lijuan Wang
- Center for Global Health, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China
| | - Yiming Feng
- Center for Global Health, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China
| | - Li Wang
- Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China
| | - Qian Wu
- Center for Global Health, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China
| | - Ping Ding
- Xiang Ya School of Public Health, Central South University, Changsha, Hunan, 410078, PR China
| | - Zhan Zhang
- Center for Global Health, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China; Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China.
| | - Lei Li
- Center for Global Health, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China; Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Nanjing, Jiangsu, 211166, PR China.
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16
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Li Q, Tang L, Qiu G, Liu C. Total mercury and methylmercury in the soil and vegetation of a riparian zone along a mercury-impacted reservoir. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:139794. [PMID: 32806376 DOI: 10.1016/j.scitotenv.2020.139794] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 06/11/2023]
Abstract
The Baihua Reservoir (Guizhou Province, Southwest China) has a history of mercury contamination associated with past acetic acid production activities at the Guizhou Organic Chemical Plant (GOCP). Soil and plant samples collected from riparian zones were analyzed for total Hg (THg) and methylmercury (MeHg) using cold vapor atomic fluorescence spectroscopy. The concentrations of THg and MeHg in soil samples were in the range of 109-371 ng g-1 and 0.32-1.80 ng g-1, respectively. Soils in the riparian zones close to the pollution source (the GOCP) presented higher Hg contamination, with relatively light Hg contamination in remote areas. This suggests a decreasing trend of THg concentrations along the riparian zones, with higher concentrations closer to the pollution source. Significant correlations were found between MeHg and soil organic matter (n = 24, p = 0.01). THg concentrations varied 11.3-161 ng g-1 in aboveground areas and 11.3-193 ng g-1 in underground areas. MeHg concentrations ranged from 0.23 to 1.06 ng g-1 in aboveground areas to 0.13-1.51 ng g-1 in the below ground areas. The vegetation studied showed different concentrations of THg and MeHg and can be considered to be impacted by Hg contamination. Different concentrations of total and methyl mercury were found among the different plant species. The high Hg concentrations in soils and vegetation suggests that the ability of Hg to bioaccumulate in riparian plants is affected by plant physiological characteristics and soil mercury concentrations. Although the bioaccumulation factors (BCFs) of the studied plants were low, their transfer factors (TFs) were >1. Our findings suggest that vegetation exhibiting TFs for THg >1 have the potential for phytoextraction in Hg-impacted riparian zones.
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Affiliation(s)
- Qiuhua Li
- Key Laboratory for Information System of Mountainous Area and Protection of Ecological Environment of Guizhou Province, Guizhou Normal University, Guiyang 550001, China; Guizhou International Science & Technology Cooperation Base-International Joint Research Centre for Aquatic Ecology, Guizhou Normal University, Guiyang 550001, China.
| | - Li Tang
- Key Laboratory for Information System of Mountainous Area and Protection of Ecological Environment of Guizhou Province, Guizhou Normal University, Guiyang 550001, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry Chinese Academy of Sciences, Guiyang 550081, China
| | - Chunhong Liu
- Faculty of Foreign Studies, Beijing Language and Culture University, Beijing 100083, China
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17
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Baldwin AK, Poulin BA, Naymik J, Hoovestol C, Clark GM, Krabbenhoft DP. Seasonal Dynamics and Interannual Variability in Mercury Concentrations and Loads through a Three-Reservoir Complex. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:9305-9314. [PMID: 32667810 DOI: 10.1021/acs.est.9b07103] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The Hells Canyon Complex (HCC) along the Snake River (Idaho-Oregon border, U.S.A.) encompasses three successive reservoirs that seasonally stratify, creating anoxic conditions in the hypolimnion that promote methylmercury (MeHg) production. This study quantified seasonal dynamics and interannual variability in mercury concentrations (inorganic divalent mercury (IHg) and MeHg) and loads at four reservoir inflow and outflow locations through the HCC (2014-2017). We observed (1) that the HCC is a net sink for both IHg and MeHg, (2) interannual variability in IHg and MeHg loads largely reflecting streamflow conditions, and (3) seasonal variability in particulate IHg loading at the inflow (greatest from February to April) and MeHg export from the outflow (greatest from September to December) of the HCC. Seasonal export of MeHg was evidenced by increases in monthly mean concentrations of unfiltered MeHg (approximately 2-fold) and the percentage of total mercury (THg) as MeHg (≥4-fold) coincident with reservoir destratification. Despite evidence of seasonal export of MeHg from the HCC, annual loads indicate a 42% decrease in unfiltered MeHg from HCC inflow to outflow. Results from this study improve the understanding of seasonal variability in mercury transport through and transformation within a reservoir complex.
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Affiliation(s)
- Austin K Baldwin
- U.S. Geological Survey, 230 Collins Road, Boise, Idaho 83702, United States
| | - Brett A Poulin
- U.S. Geological Survey, 3215 Marine Street, Suite E127, Boulder, Colorado 80303, United States
- Department of Environmental Toxicology, University of California Davis, 1 Shields Avenue, Davis, CA 95616, United States
| | - Jesse Naymik
- Idaho Power Company, 1221 West Idaho Street, Boise, Idaho 83702, United States
| | - Charles Hoovestol
- Idaho Power Company, 1221 West Idaho Street, Boise, Idaho 83702, United States
| | - Gregory M Clark
- U.S. Geological Survey, 230 Collins Road, Boise, Idaho 83702, United States
| | - David P Krabbenhoft
- U.S. Geological Survey, 8505 Research Way, Middleton, Wisconsin 53562, United States
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18
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Li Y, Gao B, Xu D, Peng W, Liu X, Qu X, Zhang M. Hydrodynamic impact on trace metals in sediments in the cascade reservoirs, North China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 716:136914. [PMID: 32045762 DOI: 10.1016/j.scitotenv.2020.136914] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/19/2020] [Accepted: 01/22/2020] [Indexed: 06/10/2023]
Abstract
Cascade reservoirs facilitate the effective use of water resources and help to alleviate existing problems of water shortage in drought-prone regions. However, the geochemical behavior and controlling mechanisms of trace metals in response to the operation of cascade reservoirs are relatively unknown. Here, trace metals (As, Cr, Cu, Li, Ni, Pb and Zn) from thirty sediment cores from cascade reservoirs (Panjiakou and Daheiting Reservoirs) in China were evaluated. Multiple methods including geochemical baseline, geostatistical analysis, factor analysis (FA), and positive matrix factorization (PMF), were combined to assess pollution status, identify and quantify potential anthropogenic sources, and determine the influence of hydrodynamic conditions on trace metals distribution. The results indicate that minor enrichment of trace metals appeared in both cascade reservoirs. However, trace metal concentrations exhibited spatial heterogeneity between two cascade reservoirs, and diverse hotspots of different metals were unexpectedly observed. This can be explained by the following three aspects: (1) Metal hotspots were detected upstream of the cascade dams via geostatistical analysis and FA, particularly for naturally sourced metals (As and Li) where dam interception resulted in higher concentrations in the upstream reservoir. (2) PMF analysis identified agricultural, industrial, and natural sources to account for 23.44%, 41.61%, and 34.95%, respectively, to the metal concentrations in the downstream reservoir. Anthropogenic emissions were the dominant factors influencing the spatial variability of Cu, Pb, and Zn between the cascade reservoirs, with higher concentrations observed in the downstream reservoir. (3) The hydrological regime also influenced the redistribution of human-derived metals, where slower flow velocities at river bends resulted in higher deposition of metal-bearing particles. This study shed light on the spatial distribution of trace metals in response to the construction and operation of cascade reservoirs, and it suggests that trace metal hotspots should be monitored to prevent potential contamination in sediments.
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Affiliation(s)
- Yanyan Li
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Bo Gao
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China.
| | - Dongyu Xu
- Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Wenqi Peng
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Xiaobo Liu
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Xiaodong Qu
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Min Zhang
- Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
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19
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Zhang Y, Chen J, Zheng W, Sun R, Yuan S, Cai H, Yang DA, Yuan W, Meng M, Wang Z, Liu Y, Liu J. Mercury isotope compositions in large anthropogenically impacted Pearl River, South China. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 191:110229. [PMID: 31986456 DOI: 10.1016/j.ecoenv.2020.110229] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 06/10/2023]
Abstract
Rivers integrate natural and anthropogenic mercury (Hg), and are important vectors of terrestrial Hg to the oceans. Here, we report the total Hg concentration and Hg isotope compositions of dissolved load in the Pearl River, the second largest river in China, in order to understand the processes and sources affecting Hg systematics in large anthropogenically-impacted river water. The dissolved Hg showed a concentration varying from 0.45 to 2.44 ng/L, within the range reported for natural background lake and river waters. All river water samples showed significantly negative δ202Hg (-2.89‰ to -0.57‰), slightly positive Δ200Hg (-0.05‰ to 0.52‰), and mostly positive Δ199Hg (0.10‰ to 0.57‰), except for three extremely negative values (-2.25‰ to -0.76‰). Combined with other geochemical parameters, we suggest that the influence of in-river processes, such as sorption and reduction, on the Hg isotope compositions is very limited, and the dissolved Hg in the Pearl River mainly comes from atmospheric precipitation and surface soil weathering. Although the whole river basin is largely affected by urban, industrial and mining activities, unlike other heavy metals, their direct contributions to dissolved Hg seem limited. It is worth noting that the three samples with very negative Δ199Hg values (down to -2.25‰) are derived from special source which attribute to the input of Hg released from the local incineration of electronic wastes. This study demonstrates that isotope approach is a powerful tool for tracing sources and pathways of Hg in large complex river systems.
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Affiliation(s)
- Yuanyuan Zhang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jiubin Chen
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou, 550081, China; Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China.
| | - Wang Zheng
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Ruoyu Sun
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Shengliu Yuan
- Chemistry Department, Trent University, Peterborough, Ontario, K9J7B8, Canada
| | - Hongming Cai
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - David Au Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wei Yuan
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Mei Meng
- Institute of Surface-Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Zhongwei Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yulong Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jianfeng Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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Jing M, Lin D, Wu P, Kainz MJ, Bishop K, Yan H, Wang R, Wang Q, Li Q. Effect of aquaculture on mercury and polyunsaturated fatty acids in fishes from reservoirs in Southwest China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 257:113543. [PMID: 31753634 DOI: 10.1016/j.envpol.2019.113543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 10/16/2019] [Accepted: 10/29/2019] [Indexed: 06/10/2023]
Abstract
Aquaculture can affect the polyunsaturated fatty acids (PUFA) and mercury (Hg) in fish by altering their diet. Here, planktivorous (silver carp and bighead carp), omnivorous and carnivorous fish with different dietary strategies were selected from two reservoirs, one with on-going aquaculture (WJD) and another without aquaculture (HF) in Southwest China. We compared the total mercury (THg), methylmercury (MeHg) contents and PUFA profiles of fish and their potential diets in these two reservoirs. THg and MeHg contents in omnivorous and carnivorous fish were lower from the WJD Reservoir, which is related to the lower THg and MeHg contents in the artificial fish food. THg and MeHg contents in silver carp from the WJD Reservoir were lower than those from the HF Reservoir, while they were similar in bighead carps from the two reservoirs. The Hg variation in planktivorous fish were inconsistent with that in plankton. THg contents in phyto- and zooplankton from the HF Reservoir were higher than those from the WJD Reservoir, yet their MeHg contents were similar. Artificial fish food which contained higher total PUFA eicosapentaenoic (EPA; 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), significantly increased the total PUFA and EPA + DHA contents in carnivorous fish, but had less effect on that in omnivorous fish from the WJD Reservoir. Eutrophication caused by aquaculture reduced total PUFA and EPA + DHA contents of plankton in WJD, yet did not reduce those in planktivorous fish. The impacts of aquaculture on Hg and PUFA accumulated in fish were varied among different fish species, and the mechanism needs further exploration.
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Affiliation(s)
- Min Jing
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Dan Lin
- School of Public Health, Guizhou Medical University, Guiyang 550025, PR China
| | - Pianpian Wu
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Sweden
| | - Martin J Kainz
- WasserCluster - Biologische Station Lunz, Inter-University Center for Aquatic Ecosystem Research, Lunz am See, Austria
| | - Kevin Bishop
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Sweden
| | - Haiyu Yan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, PR China.
| | - Rui Wang
- College of Environmental Science and Engineering, Tong ji University, Shanghai 20092, PR China
| | - Qing Wang
- Institute of Hydrobiology, Jinan University, Guangzhou 510000, PR China
| | - Qiuhua Li
- Key Laboratory for Information System of Mountainous Area and Protection of Ecological Environment of Guizhou Province Guizhou Normal University, Guiyang, 550000, PR China
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Jiang T, Bravo AG, Skyllberg U, Björn E, Wang D, Yan H, Green NW. Influence of dissolved organic matter (DOM) characteristics on dissolved mercury (Hg) species composition in sediment porewater of lakes from southwest China. WATER RESEARCH 2018; 146:146-158. [PMID: 30243058 DOI: 10.1016/j.watres.2018.08.054] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 08/20/2018] [Accepted: 08/25/2018] [Indexed: 06/08/2023]
Abstract
The origin and composition of dissolved organic matter (DOM) in porewater of lake sediments is intricate and decisive for fate of pollutants including mercury (Hg). While there are many reports on the relationship between dissolved organic carbon concentration (DOC) and mercury (Hg) concentrations in aquatic systems, there are few in which DOM compositional properties, that may better explain the fate of Hg, have been the focus. In this study, porewaters from sediments of three lakes, Caihai Lake (CH), Hongfeng Lake (HF) and Wujiangdu Lake (WJD), all located in southwest China, were selected to test the hypothesis that DOM optical properties control the fate of Hg in aquatic ecosystems. Porewater DOM was extracted and characterized by UV-Vis absorption and fluorescence spectroscopy. A two end-member (autochthonous and allochthonous DOM) mixing model was used to unveil the origin of DOM in porewaters of the three lakes. Our results show a higher input of terrestrial DOM in the pristine lake CH, as compared to lakes HF and WJD lakes, which were both influenced by urban environments and enriched in autochthonous DOM. While the relationships between the concentrations of DOC and the different chemical forms of Hg forms were quite inconsistent, we found important links between specific DOM components and the fate of Hg in the three lakes. In particular, our results suggest that allochthonous, terrestrial DOM inhibits Hg(II) availability for Hg methylating micro-organisms. In contrast, autochthonous DOM seems to have been stimulated MeHg formation, likely by enhancing the activity of microbial communities. Indeed, DOM biodegradation experiments revealed that differences in the microbial activity could explain the variation in the concentration of MeHg. While relationships between concentrations of DOC and Hg vary among different sites and provide little information about Hg cycling, we conclude that the transport and transformation of Hg (e.g. the methylation process) are more strongly linked to DOM chemical composition and reactivity.
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Affiliation(s)
- Tao Jiang
- Department of Environment Science and Engineering, College of Resources and Environment, Southwest University, Chongqing, 400716, China; Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå SE-90183, Sweden
| | - Andrea G Bravo
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish National Research Council (CSIC), Barcelona, 08034, Spain
| | - Ulf Skyllberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå SE-90183, Sweden
| | - Erik Björn
- Department of Chemistry, Umeå University, SE-901-87, Umeå, Sweden
| | - Dingyong Wang
- Department of Environment Science and Engineering, College of Resources and Environment, Southwest University, Chongqing, 400716, China
| | - Haiyu Yan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
| | - Nelson W Green
- School of Chemical and Biomolecular Engineering, Atlanta, GA, 30332, United States
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Tao Z, Bian R, Chai X. Methylmercury levels in cover soils from two landfills in Xi'an and Shanghai, China: Implications for mercury methylation potentials. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 78:331-336. [PMID: 32559919 DOI: 10.1016/j.wasman.2018.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 05/22/2018] [Accepted: 06/05/2018] [Indexed: 06/11/2023]
Abstract
Landfills are considered important sources of mercury for surrounding ecosystems. Methylmercury (MeHg) levels in waste layers have been studied extensively; however, the levels of MeHg in cover soils remain undefined. Here, total mercury (THg) and MeHg concentrations in surface cover soils and soil cores from two landfills in China and possible factors affecting Hg methylation were studied. The mean MeHg concentration in surface cover soils from both landfills was 0.048 ng g-1, suggesting that cover soil layers are not active sites of MeHg production. Soil MeHg concentrations in both landfills were affected little by closure time. In the Jiangcungou landfill, no correlations between MeHg concentration and the measured environmental factors (e.g., THg, soil pH, organic matter (OM), and S) were observed that indicated that these parameters might have indirect effects on MeHg concentration. However, in the Laogang landfill, significant correlations were found between MeHg concentration and the measured environmental factors. The results showed that MeHg concentration in the surface cover soil from area D of the Laogang landfill is regulated mainly by soil pH, OM, and S, and that its vertical distribution in areas C and D is regulated mainly by soil pH and soil OM, respectively. These findings fill a knowledge gap regarding MeHg levels in cover soils and they advance our understanding of Hg cycling in landfills, presenting positive implications for landfill management and risk assessment of MeHg.
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Affiliation(s)
- Zhengkai Tao
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, PR China
| | - Rongxing Bian
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, PR China
| | - Xiaoli Chai
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, PR China.
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Noh S, Kim J, Hur J, Hong Y, Han S. Potential contributions of dissolved organic matter to monomethylmercury distributions in temperate reservoirs as revealed by fluorescence spectroscopy. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:6474-6486. [PMID: 29250731 DOI: 10.1007/s11356-017-0913-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 12/01/2017] [Indexed: 06/07/2023]
Abstract
The monomethylmercury (MMHg) concentrations, water quality parameters (e.g., pH, suspended particles, total phosphorus, sulfate, and chlorophyll-a), and compositions of dissolved organic matter (DOM) were analyzed to understand how the quality of DOM is related to the MMHg distributions in the surface waters of 14 reservoirs. The excitation-emission matrix (EEM) fluorescence spectroscopy identified six fluorescence peaks, and a parallel factor analysis (PARAFAC) of EEM spectra identified three components of DOM: microbial humic-like (C1), terrestrial humic-like (C2), and protein-like DOM (C3). Using the observation data, the principal component analysis (PCA) were carried out to understand the relative importance of the fluorescence properties of DOM, representing DOM quality, on the MMHg distribution. The loading plot of PCA showed a strong positive correlation between the MMHg and protein regions of the EEM spectra and no correlation between MMHg and the terrestrial humic regions of the EEM, suggesting that autochthonous DOM production is a key factor in increasing MMHg concentration in reservoir water. The preliminary mass flux estimation, which was carried out to identify the major sources of MMHg in Okjeong reservoir, revealed that the major sources are sediment diffusion and water column methylation. Because the studied reservoirs are located remotely from a large-sized river and industrial region, most MMHg in reservoir water is likely diffused from the surface sediment or produced in the water column, and these sources tend to increase in reservoirs enriched with autochthonous DOM. It is suggested that EEM fluorescence can improve our ability to trace the major sources of MMHg in diverse reservoirs.
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Affiliation(s)
- Seam Noh
- Division of Chemical Research, National Institute of Environmental Research (NIER), Incheon, 22689, Republic of Korea
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Jihee Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Jin Hur
- Department of Environment and Energy, Sejong University, Seoul, 05006, Republic of Korea
| | - Yongseok Hong
- Department of Environmental Engineering, Daegu University, Daegu, 38453, Republic of Korea
| | - Seunghee Han
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea.
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Study on Mercury Distribution and Speciation in Urban Road Runoff in Nanjing City, China. WATER 2017. [DOI: 10.3390/w9100779] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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