1
|
Jung E, Park S, Kim H, Han S. Spatiotemporal variation in methylmercury and related water quality variables in a temperate river under highly dynamic hydrologic conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 932:173090. [PMID: 38729360 DOI: 10.1016/j.scitotenv.2024.173090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 04/14/2024] [Accepted: 05/07/2024] [Indexed: 05/12/2024]
Abstract
The understanding of the essential environmental factors affecting the spatiotemporal variation in methylmercury (MeHg) in river water is limited to date, despite its importance for predicting the effect of ongoing climate change on MeHg accumulation in freshwater ecosystems. This study aimed to explore the variation in MeHg concentration and related environmental factors in the downstream zone of the Yeongsan River under highly dynamic hydrologic conditions by using water quality and hydrologic data collected from 1997 to 2022, and Hg and MeHg data collected from 2017 to 2022. The mean concentration of unfiltered MeHg was 35.7 ± 13.7 pg L-1 (n = 24) in summer and 26.7 ± 7.43 pg L-1 (n = 24) in fall. Dissolved oxygen (DO), conductivity, nitrate, and dissolved organic carbon (DOC) were determined to be the most influential variables in terms of MeHg variation based on the partial least squares regression model, and their effects on the MeHg concentration were negative, except for DOC. Heatmaps representing the similarity distances between temporal trends of hydrologic and water quality variables were constructed to determine fundamental factors related to the time-based variations in DO, conductivity, nitrate, and DOC using a dynamic time warping algorithm. The heatmap cluster analysis showed that the temporal trends of these variables were closely related to rainfall variation rather than irradiance or water temperature. Overall, biogeochemical factors directly related to in situ methylation rate of Hg(II)-rather than transport of Hg(II) and MeHg from external sources-mainly control the spatiotemporal variation of MeHg in the downstream zone of the Yeongsan River.
Collapse
Affiliation(s)
- Eunji Jung
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea; Research Center for Innovative Energy and Carbon Optimized Synthesis for Chemicals, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Sungsook Park
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea; Research Center for Innovative Energy and Carbon Optimized Synthesis for Chemicals, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Hyunji Kim
- National Institute of Environmental Research (NIER), Incheon 22689, Republic of Korea
| | - Seunghee Han
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea; Research Center for Innovative Energy and Carbon Optimized Synthesis for Chemicals, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.
| |
Collapse
|
2
|
Asuku AO, Ayinla MT, Ajibare AJ, Olajide TS. Mercury chloride causes cognitive impairment, oxidative stress and neuroinflammation in male Wistar rats: The potential protective effect of 6-gingerol-rich fraction of Zingiber officinale via regulation of antioxidant defence system and reversal of pro-inflammatory markers increase. Brain Res 2024; 1826:148741. [PMID: 38157955 DOI: 10.1016/j.brainres.2023.148741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/19/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
This study investigated the effects of 6-gingerol-rich fraction of Zingiber officinale (6-GIRIFZO) on mercury chloride (HgCl2)-induced neurotoxicity in Wistar rats. Thirty -five male Wistar rats weighing between (150-200 g) were divided randomly into five groups (n = 7): group 1: control, received 0.5 mL of normal saline, group 2: received HgCl2 (5 mg/kg), group 3: received N-acetylcysteine (NAC) (50 mg/kg) as well as HgCl2 (5 mg/kg), group 4: received 6-GIRIFZO (100 mg/kg) and HgCl2 (5 mg/kg), group 5: had 6-GIRIFZO (200 mg/kg) and HgCl2 (5 mg/kg), consecutively for 14 days. On the day14, the rats were subjected to behavioural tests using a Morris water maze and novel object recognition tests. The rats were then euthanized to obtain brain samples for the determination of biochemical parameters (acetylcholinesterase (AchE), nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione (GSH), tumor necrosis factor- alpha (TNF-α), nuclear factor kappa-B (NF-κB), interleukin-1β (IL-1β) and interleukin-6 (IL-6)) using standard methods. The result revealed a significant increase in escape latency and a significant decrease in recognition ratio in the rats that were exposed to HgCl2 only. However, 6-GIRIFZO produced a significant reduction in the escape latency and (p < 0.05) increase in the recognition ratio. Similarly, HgCl2 exposure caused a significant (p < 0.05) decrease in the brain SOD, GPx, CAT, GSH with increased brain levels of MDA, NO, AchE, TNF-α, NF-κB, IL-1β and IL-6. Similarly to the standard drug, NAC, 6-GIRIFZO (100 and 200 mg/kg) significantly (p < 0.05) increased brain SOD, GPx, CAT, and GSH levels with decreased concentrations of MDA, NO, AchE, TNF-α, NF-κB, IL-1β and IL-6. Also, pre-treatment with 6-GIRIFZO prevented the HgCl2-induced morphological aberrations in the rats. This study concludes that 6-GIRIFZO prevents HgCl2-induced cognitive deficit via reduction of brain inflammation as well as oxidative stress in rats.
Collapse
Affiliation(s)
- Abraham Olufemi Asuku
- Bioresources Development Centre, National Biotechnology Development Agency (NABDA), Ogbomoso, Nigeria; Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Ilorin, Nigeria.
| | - Maryam Tayo Ayinla
- Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Ilorin, Nigeria
| | - Ayodeji Johnson Ajibare
- Department of Physiology, Faculty of Basic Medical Sciences, College of Medicine, Lead City University, Ibadan, Oyo State, Nigeria
| | - Tobiloba Samuel Olajide
- Department of Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Ilorin, Nigeria
| |
Collapse
|
3
|
Wei R, Wei P, Yuan H, Yi X, Aschner M, Jiang YM, Li SJ. Inflammation in Metal-Induced Neurological Disorders and Neurodegenerative Diseases. Biol Trace Elem Res 2024:10.1007/s12011-023-04041-z. [PMID: 38206494 DOI: 10.1007/s12011-023-04041-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 12/23/2023] [Indexed: 01/12/2024]
Abstract
Essential metals play critical roles in maintaining human health as they participate in various physiological activities. Nonetheless, both excessive accumulation and deficiency of these metals may result in neurotoxicity secondary to neuroinflammation and the activation of microglia and astrocytes. Activation of these cells can promote the release of pro-inflammatory cytokines. It is well known that neuroinflammation plays a critical role in metal-induced neurotoxicity as well as the development of neurological disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). Initially seen as a defense mechanism, persistent inflammatory responses are now considered harmful. Astrocytes and microglia are key regulators of neuroinflammation in the central nervous system, and their excessive activation may induce sustained neuroinflammation. Therefore, in this review, we aim to emphasize the important role and molecular mechanisms underlying metal-induced neurotoxicity. Our objective is to raise the awareness on metal-induced neuroinflammation in neurological disorders. However, it is not only just neuroinflammation that different metals could induce; they can also cause harm to the nervous system through oxidative stress, apoptosis, and autophagy, to name a few. The primary pathophysiological mechanism by which these metals induce neurological disorders remains to be determined. In addition, given the various pathways through which individuals are exposed to metals, it is necessary to also consider the effects of co-exposure to multiple metals on neurological disorders.
Collapse
Affiliation(s)
- Ruokun Wei
- Toxicology Department, School of Public Health, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, China
- Guangxi Key Laboratory of Environment and Health Research, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, Guangxi, China
| | - Peiqi Wei
- Toxicology Department, School of Public Health, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, China
- Guangxi Key Laboratory of Environment and Health Research, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, Guangxi, China
| | - Haiyan Yuan
- Toxicology Department, School of Public Health, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, China
- Guangxi Key Laboratory of Environment and Health Research, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, Guangxi, China
| | - Xiang Yi
- Toxicology Department, School of Public Health, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, China
- Guangxi Key Laboratory of Environment and Health Research, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, Guangxi, China
| | - Michael Aschner
- The Department of Molecular Pharmacology at Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Yue-Ming Jiang
- Toxicology Department, School of Public Health, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, China.
- Guangxi Key Laboratory of Environment and Health Research, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, Guangxi, China.
| | - Shao-Jun Li
- Toxicology Department, School of Public Health, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, China.
- Guangxi Key Laboratory of Environment and Health Research, Guangxi Medical University, 22 Shuang-yong Rd., Nanning, 530021, Guangxi, China.
| |
Collapse
|
4
|
Ci Z, Tang X, Shen W, Chen B. Coastal streams and sewage outfalls: Hot spots of mercury discharge, pollution and cycling in nearshore environments. MARINE POLLUTION BULLETIN 2023; 195:115536. [PMID: 37708606 DOI: 10.1016/j.marpolbul.2023.115536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 09/04/2023] [Accepted: 09/08/2023] [Indexed: 09/16/2023]
Abstract
The coastal streams (CSs) and sewage outfalls (SOs) are widely distributed and direct anthropogenic stress on global coastal ecosystems. However, the CS/SO-associated mercury (Hg) discharge, pollution and cycle in nearshore environment are less quantified. Here, we report that total Hg (THg) and methylmercury (MMHg) concentrations in waters of CSs (n = 8) and SOs (n = 15) of the northern China were ∼102 to 103 times of coastal surface waters and 10 to 102 times of major rivers in China and other regions. The CS/SO discharges resulted in the increase of total organic carbon (TOC) contents, THg and MMHg concentrations and TOC-normalized THg and MMHg concentrations in sediments of CS/SO-impacted coasts. The laboratory experiments further illustrated that the CS/SO-impacted sediments characterized with high potentials of dissolved THg and MMHg productions and releases. Our findings indicate that the layout optimization of SOs is able to reduce the Hg risk in coastal environment.
Collapse
Affiliation(s)
- Zhijia Ci
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-sen University, Zhuhai 519082, China.
| | - Xiong Tang
- Guangdong Eco-Engineering Polytechnic, Guangzhou 510520, China
| | - Wenjie Shen
- School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai 519082, China; Guangdong Key Laboratory of Geological Process and Mineral Resources Exploration, Zhuhai 519082, China
| | - Baowei Chen
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-sen University, Zhuhai 519082, China
| |
Collapse
|
5
|
Abdelhamid MS, El Bohi KM, Sherif MH, Abdelhamid MS, Abdel-Daim MM, Elewa YHA, Metwally MMM, Albadrani GM, Najda A, El Abdel-Hamid S, Abu-Zeid EH. Apitoxin alleviates methyl mercury-induced peripheral neurotoxicity in male rats by regulating dorsal root ganglia neuronal degeneration and oxidative stress. Biomed Pharmacother 2023; 161:114521. [PMID: 36921536 DOI: 10.1016/j.biopha.2023.114521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/02/2023] [Accepted: 03/09/2023] [Indexed: 03/16/2023] Open
Abstract
Methylmercury (MeHg) toxicity is associated with extensive neuronal degeneration of dorsal root ganglia (DRG). This study aimed to assess the ameliorative effect of bee venom (BV) on methyl mercury chloride (MeHgCl)-induced peripheral neurotoxicity using DRGs in rats. Forty-eight adult male Sprague Dawley rats were allocated into four equal groups: G I: control (gavaged MilliQ water 1 ml/rat), G II: subcutaneously injected with BV (0.5 mg/kg b.wt), G III: gavaged MeHgCl (6.7 mg/kg b.wt), and G IV: received MeHgCl+BV. Dosing was done five times/week for 2 weeks. Ataxic behavior and visual impairments were significantly increased, whereas the movement behavior and motility gait were suppressed in the MeHgCl group. MeHgCl significantly decreased total antioxidant capacity (TAC) in DRG and significantly decreased the serum levels of glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). Tumor necrosis factor-alpha (TNF-α) and interleukin 1β (IL-1β) levels were significantly elevated, whereas interleukin 10 (IL-10) levels were significantly decreased in the MeHgCl group compared with the control group. DRGs of the MeHgCl-exposed rats showed pyknotic shrunken neurons with perineural vacuolations, demyelination of nerve axons, and proliferation of the satellite cells. MeHgCl significantly induced a higher positive index ratio of Iba-1, SOX10, neurofilament, pan-neuron, and vimentin immunostaining in the DRG. BV administration significantly mitigated the MeHgCl-induced alterations in oxidative stress-related indices. BV modified the immunostaining of Iba-1, SOX10, neurofilament, pan-neuron, and vimentin-positive index ratio in the DRG of the MeHgCl group. Our findings acknowledged that BV could enhance in vivo neuroprotective effects against MeHgCl-induced DRGs damage in male rats.
Collapse
Affiliation(s)
- Moustafa S Abdelhamid
- Biochemistry division, Chemistry Department, Faculty of Science, Zagazig University, 44511, Egypt
| | - Khlood M El Bohi
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Zagazig University, 44511, Egypt
| | - Mohamed H Sherif
- Biochemistry division, Chemistry Department, Faculty of Science, Zagazig University, 44511, Egypt
| | - Manar S Abdelhamid
- Biochemistry division, Chemistry Department, Faculty of Science, Zagazig University, 44511, Egypt
| | - Mohamed M Abdel-Daim
- Department of Pharmaceutical Sciences, Pharmacy Program, Batterjee Medical College, P.O. Box 6231, Jeddah 21442, Saudi Arabia; Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Yaser H A Elewa
- Department of Histology and Cytology, Faculty of Veterinary Medicine, Zagazig University, 44511, Egypt; Laboratory of Anatomy, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Mohamed M M Metwally
- Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44511, Egypt
| | - Ghadeer M Albadrani
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, B.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Agnieszka Najda
- Department of Vegetable Crops and Medicinal Plants University of Life Sciences in Lublin, 50 A Doświadczalna Street, 20-280 Lublin, Poland.
| | - Shereen El Abdel-Hamid
- Department of Behavior and Management of Animal, Poultry and Aquatics, Faculty of Veterinary Medicine, Zagazig University, 44511, Egypt
| | - Ehsan H Abu-Zeid
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Zagazig University, 44511, Egypt.
| |
Collapse
|
6
|
Bradford MA, Mallory ML, O'Driscoll NJ. The Complex Interactions Between Sediment Geochemistry, Methylmercury Production, and Bioaccumulation in Intertidal Estuarine Ecosystems: A Focused Review. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2022; 110:26. [PMID: 36571620 DOI: 10.1007/s00128-022-03653-w] [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: 07/20/2022] [Accepted: 11/20/2022] [Indexed: 06/17/2023]
Abstract
Due to their natural geochemistry, intertidal estuarine ecosystems are vulnerable to bioaccumulation of methylmercury (MeHg), a neurotoxin that readily bioaccumulates in organisms. Determining MeHg concentrations in intertidal invertebrates at the base of the food web is crucial in determining MeHg exposure in higher trophic level organisms like fish and birds. The processes that govern the production of MeHg in coastal ecosystems are influenced by many geochemical factors including sulfur species, organic matter, and salinity. The interactions of these factors with mercury are complex, and a wide variety of results have been reported in the literature. This paper reviews conceptual models to better clarify the various geochemical and physical factors that impact MeHg production and bioavailability in intertidal ecosystems.
Collapse
Affiliation(s)
| | - Mark L Mallory
- Biology Department, Acadia University, Wolfville, NS, Canada
| | - Nelson J O'Driscoll
- Earth and Environmental Science Department, Acadia University, Wolfville, NS, Canada
| |
Collapse
|
7
|
Qu P, Pang M, Wang P, Ma X, Zhang Z, Wang Z, Gong Y. Bioaccumulation of mercury along continuous fauna trophic levels in the Yellow River Estuary and adjacent sea indicated by nitrogen stable isotopes. JOURNAL OF HAZARDOUS MATERIALS 2022; 432:128631. [PMID: 35306412 DOI: 10.1016/j.jhazmat.2022.128631] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/14/2022] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
Mercury (Hg), and its organic forms, are some of the most hazardous elements, with strong toxicity, persistence, and biological accumulation in marine organisms. Hg accumulation in continuous trophic levels (TL) in marine food chains remains unclear. In this study, individual invertebrate and fish samples collected from the Yellow River Estuary adjacent sea were grouped into continuous TL ranges, and the bioaccumulations of total Hg (THg) and methylmercury (MeHg) were analyzed. The trophic magnification factor in invertebrates and fish was 1.40 and 1.72 for THg, and 2.56 and 2.17 for MeHg, indicating that both THg and MeHg were significantly biomagnified with increasing TL in both invertebrates and fish through trophic transfer. To evaluate the health risk of seafood consumption, the target hazard quotient (THQ) was calculated. Increasing THQ values indicated that the health risks of invertebrate and fish consumption in humans, especially children, were both elevated with increasing TL. THQ values > 1 indicated that consumption of invertebrates at a TL above 4.0 and fish above 4.5 may pose a relatively higher risk for children. Therefore, the consumption of both individual invertebrates and fish at high trophic positions may present greater health risk, especially in young children.
Collapse
Affiliation(s)
- Pei Qu
- Observation and Research Station of Bohai Eco-Corridor & Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources of the People's Republic of China, No. 6, Xianxialing Road, Qingdao, China; Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 168, Wenhaizhong Road, Jimo District, Qingdao City, Shandong, China
| | - Min Pang
- Observation and Research Station of Bohai Eco-Corridor & Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources of the People's Republic of China, No. 6, Xianxialing Road, Qingdao, China; Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 168, Wenhaizhong Road, Jimo District, Qingdao City, Shandong, China.
| | - Penggong Wang
- China Certification & Inspection Group Shandong Testing Co., LTD., Jiaozhou District, Qingdao City, Shandong, China
| | - Xuli Ma
- China Certification & Inspection Group Shandong Co., LTD., Shinan District, Qingdao City, Shandong, China
| | - Zhaohui Zhang
- Observation and Research Station of Bohai Eco-Corridor & Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources of the People's Republic of China, No. 6, Xianxialing Road, Qingdao, China; Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 168, Wenhaizhong Road, Jimo District, Qingdao City, Shandong, China
| | - Zongling Wang
- Observation and Research Station of Bohai Eco-Corridor & Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources of the People's Republic of China, No. 6, Xianxialing Road, Qingdao, China; Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 168, Wenhaizhong Road, Jimo District, Qingdao City, Shandong, China
| | - Yuchen Gong
- The Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao City, Shandong, China
| |
Collapse
|
8
|
Wu Z, Li Z, Shao B, Zhang Y, He W, Lu Y, Gusvitskii K, Zhao Y, Liu Y, Wang X, Tong Y. Impact of dissolved organic matter and environmental factors on methylmercury concentrations across aquatic ecosystems inferred from a global dataset. CHEMOSPHERE 2022; 294:133713. [PMID: 35074323 DOI: 10.1016/j.chemosphere.2022.133713] [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: 10/14/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 06/14/2023]
Abstract
Mercury (Hg) input into ecosystems is estimated to have increased by twofold to fivefold since the industrial revolution. In aquatic ecosystems, methylmercury (MeHg) receives the most attentions of all the Hg species due to its neurotoxicity and strong bioaccumulation capacity in food chain. Dissolved organic matter (DOM) is crucial in impacting aquatic Hg transformation. However, only few spatially constrained studies have attempted to quantify the relative importance of DOM and other factors (e.g., Hg availability, temperature, pH, and land-use type) on MeHg concentration. In this study, we collected data of 585 water samples at 373 sites globally, including lakes, rivers, estuaries, and wetlands, and characterized the global pattern of MeHg distribution and environmental drivers of aquatic MeHg concentration. Our results showed that MeHg concentrations ranged from detection limits to 11 (geometric mean 0.11 and average 0.29) ng/L, and the highest MeHg concentration and Hg methylation potential were observed in wetlands. A positive relationship was observed between MeHg fraction in the total mercury (THg) and DOM for all the aquatic ecosystems. Using the structural equation modeling, we found that Hg availability was a dominant factor in impacting water MeHg concentration followed by DOM. According to 129 samples of specific DOM source information, we found that the percentage of THg as MeHg (%MeHg) in water dominated by the autochthonous DOM was higher than that dominated by the allochthonous DOM. Our results could advance understanding of aquatic Hg cycling and their environmental drivers, which are fundamental for predicting and mitigating MeHg productions and its potential health risks for humans.
Collapse
Affiliation(s)
- Zhengyu Wu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Zhike Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Bo Shao
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Yiyan Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Wei He
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, China
| | - Yiren Lu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Kair Gusvitskii
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Yurong Liu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xuejun Wang
- College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Yindong Tong
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China.
| |
Collapse
|
9
|
Wang T, Obrist D. Inorganic and methylated mercury dynamics in estuarine water of a salt marsh in Massachusetts, USA. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 294:118657. [PMID: 34890749 DOI: 10.1016/j.envpol.2021.118657] [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: 05/21/2021] [Revised: 11/06/2021] [Accepted: 12/06/2021] [Indexed: 05/26/2023]
Abstract
Salt marsh estuaries serve as sources and sinks for nutrients and elements to and from estuarine water, which enhances and alleviates watershed fluxes to the coastal ocean. We assessed sources and sinks of mercury in the intertidal Plum Island Sound estuary in Massachusetts, the largest salt marsh estuary of New England, using 25-km spatial water sampling transects. Across all seasons, dissolved (FHg) and total (THg) mercury concentrations in estuarine water were highest and strongly enhanced in upper marshes (1.31 ± 0.20 ng L-1 and 6.56 ± 3.70 ng L-1, respectively), compared to riverine Hg concentrations (0.86 ± 0.17 ng L-1 and 0.88 ± 0.34 ng L-1, respectively). Mercury concentrations declined from upper to lower marshes and were lowest in ocean water (0.38 ± 0.10 ng L-1 and 0.56 ± 0.25 ng L-1, respectively). Conservative mixing models using river and ocean water as endmembers indicated that internal estuarine Hg sources strongly enhanced estuarine water Hg concentrations. For FHg, internal estuarine Hg contributions were estimated at 26 g yr-1 which enhanced Hg loads from riverine sources to the ocean by 44%. For THg, internal sources amounted to 251 g yr-1 and exceeded riverine sources six-fold. Proposed sources for internal estuarine mercury contributions include atmospheric deposition to the large estuarine surface area and sediment re-mobilization, although sediment Hg concentrations were low (average 23 ± 2 μg kg-1) typical of uncontaminated sediments. Soil mercury concentrations under vegetation, however, were ten times higher (average 200 ± 225 μg kg-1) than in intertidal sediments suggesting that high soil Hg accumulation might drive lateral export of Hg to the ocean. Spatial transects of methylated Hg (MeHg) showed no concentration enhancements in estuarine water and no indication of internal MeHg sources or formation. Initial mass balance considerations suggest that atmospheric deposition may either be in similar magnitude, or possibly exceed lateral tidal export which would be consistent with strong Hg accumulation observed in salt marsh soils sequestering Hg from current and past atmospheric deposition.
Collapse
Affiliation(s)
- Ting Wang
- Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts Lowell, Lowell, MA, 01854, USA.
| | - Daniel Obrist
- Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts Lowell, Lowell, MA, 01854, USA.
| |
Collapse
|
10
|
Tercier-Waeber ML, Confalonieri F, Abdou M, Dutruch L, Bossy C, Fighera M, Bakker E, Graziottin F, van der Wal P, Schäfer J. Advanced multichannel submersible probe for autonomous high-resolution in situ monitoring of the cycling of the potentially bioavailable fraction of a range of trace metals. CHEMOSPHERE 2021; 282:131014. [PMID: 34118619 DOI: 10.1016/j.chemosphere.2021.131014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/19/2021] [Accepted: 05/26/2021] [Indexed: 06/12/2023]
Abstract
We report here on the development and application of a submersible, compact, low power consumption, integrated multichannel trace metal sensing probe (TracMetal). This probe is unique in that it allows high-resolution, simultaneous in-situ measurements of the potentially bioavailable (so-called dynamic) fraction of Hg(II), As(III), Cd(II), Pb(II), Cu(II), Zn(II). The TracMetal incorporates nanostructured Au-plated and Hg-plated gel-integrated microelectrode arrays. In addition to be selective to the fraction of metal potentially bioavailable, they offer protection against fouling and ill-controlled convective interferences. Sensitivities in the low pM for Hg(II) and sub-nM for the other target trace metals is achieved with precision ≤ 12%. The TracMetal is capable of autonomous operation during deployment, with routines for repetitive measurements (1-2 h-1), data storage and management, data computer visualization, and wireless data transfer. The system was successfully applied in the Arcachon Bay, to study the temporal variation of the dynamic fraction of the trace metals targeted. The in situ autonomous TracMetal measurements were combined with in situ measurements of the master bio-physicochemical parameters and sample collection for complementary measurements of the dissolved metal concentrations, organic matter concentrations and proxy for biological activities. The integration of all data revealed that various biotic and abiotic processes control the temporal variation of the dynamic fractions of the target metals (Medyn). The difference in the percentage of the dynamic forms of the metals studied and the short-term processes influencing their variation highlight the TracMetal potentiality as metal bioavailability-assessment sentinel to achieve comprehensive environmental monitoring of dynamic aquatic systems.
Collapse
Affiliation(s)
- Mary-Lou Tercier-Waeber
- University of Geneva, Dept. of Inorganic and Analytical Chemistry, 1211 Geneva 4, Switzerland.
| | | | - Melina Abdou
- University of Geneva, Dept. of Inorganic and Analytical Chemistry, 1211 Geneva 4, Switzerland; University of Bordeaux, UMR CNRS 5805 EPOC, 33615 Pessac, France
| | - Lionel Dutruch
- University of Bordeaux, UMR CNRS 5805 EPOC, 33615 Pessac, France
| | - Cécile Bossy
- University of Bordeaux, UMR CNRS 5805 EPOC, 33615 Pessac, France
| | - Marianna Fighera
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Eric Bakker
- University of Geneva, Dept. of Inorganic and Analytical Chemistry, 1211 Geneva 4, Switzerland
| | | | - Peter van der Wal
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Jörg Schäfer
- University of Bordeaux, UMR CNRS 5805 EPOC, 33615 Pessac, France
| |
Collapse
|
11
|
Pavoni E, Petranich E, Signore S, Fontolan G, Covelli S. The Legacy of the Idrija Mine Twenty-Five Years after Closing: Is Mercury in the Water Column of the Gulf of Trieste Still an Environmental Issue? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:10192. [PMID: 34639493 PMCID: PMC8508114 DOI: 10.3390/ijerph181910192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/16/2021] [Accepted: 09/23/2021] [Indexed: 01/03/2023]
Abstract
Mercury (Hg) contamination in the Gulf of Trieste (northern Adriatic Sea) due to mining activity in Idrija (Slovenia) still represents an issue of environmental concern. The Isonzo/Soča River's freshwater inputs have been identified as the main source of Hg into the Gulf, especially following periods of medium-high discharge. This research aims to evaluate the occurrence and distribution of dissolved (DHg) and particulate (PHg) Hg along the water column in the northernmost sector of the Gulf, a shallow and sheltered embayment suitable for the accumulation of fine sediments. Sediment and water samples were collected under unperturbed and perturbed environmental conditions induced by natural and anthropogenic factors. Mercury in the sediments (0.77-6.39 µg g-1) and its relationship to grain size were found to be consistent with previous research focused on the entire Gulf, testifying to the common origin of the sediment. Results showed a notable variability of DHg (
Collapse
Affiliation(s)
- Elena Pavoni
- Dipartimento di Matematica e Geoscienze, Università Degli Studi di Trieste, Via Weiss 2, 34128 Trieste, Italy; (E.P.); (E.P.); (G.F.)
| | - Elisa Petranich
- Dipartimento di Matematica e Geoscienze, Università Degli Studi di Trieste, Via Weiss 2, 34128 Trieste, Italy; (E.P.); (E.P.); (G.F.)
| | - Sergio Signore
- Autorità di Sistema Portuale del Mare Adriatico Orientale-Porto di Trieste, Via Karl Ludwig Von Bruck 3, 34144 Trieste, Italy;
| | - Giorgio Fontolan
- Dipartimento di Matematica e Geoscienze, Università Degli Studi di Trieste, Via Weiss 2, 34128 Trieste, Italy; (E.P.); (E.P.); (G.F.)
| | - Stefano Covelli
- Dipartimento di Matematica e Geoscienze, Università Degli Studi di Trieste, Via Weiss 2, 34128 Trieste, Italy; (E.P.); (E.P.); (G.F.)
| |
Collapse
|
12
|
Different Mercury Species Partitioning and Distribution in the Water and Sediment of a Eutrophic Estuary in Northern Taiwan. WATER 2021. [DOI: 10.3390/w13182471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The total Hg and methyl Hg in waters and sediments, as well as particulate total Hg (PTHg), were analyzed to study their distribution and partitioning in the Danshuei River Estuary (DRE), northern Taiwan. TOC and grain size were also determined in the sediment samples. The dissolved total Hg (DTHg) in waters ranged from 24.0 to 45.8 ng/L. The dissolved methyl Hg (DMeHg) concentrations contributed 0.6–30.4% of the DTHg pool, with the higher percentage appearing in the upper estuary. The DMeHg concentration positively correlated with the Chl.a within the estuary, suggesting that phytoplankton plays an important role in influencing the DMeHg concentration. The partitioning results indicated that DTHg chiefly dominates the THg (DTH + PTHg) pool, especially at a salinity of >15 psu region. The value of partition coefficient, log(KD), was within a range of 3.54 to 4.68, and the value linearly decreased with increasing salinity. The sediment total Hg (STHg) concentrations ranged from 80 to 379 ng/g, and most data exceeded the NOAA guidelines value (ERL < 150 ng/g), indicating that the DRE is contaminated with Hg. The STHg concentrations inversely and positively correlated with the grain size and TOC content, respectively, suggesting that sediment Hg distributions are strongly influenced by the both parameters.
Collapse
|
13
|
Legacy of Past Mining Activity Affecting the Present Distribution of Dissolved and Particulate Mercury and Methylmercury in an Estuarine Environment (Nalón River, Northern Spain). APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11104396] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
At the Nalón River estuary (Asturias, Northern Spain), the occurrence of Hg is due to historical mining activity which has resulted in environmental issues of great concern. Although several studies have investigated the sediment compartment regarding Hg contamination, no information is currently available on the fate of Hg and MeHg in the water column. Considering different hydrodynamic/seasonal conditions, water samples were collected along the estuary to evaluate Hg and MeHg distribution and partitioning behaviour between solid and aqueous phases. The complementary effect of the river discharge and tidal currents contributed to the prevalence of the dissolved (4.02 ± 1.33 ng L−1) or particulate (8.37 ± 4.20 ng L−1) Hg under different conditions of discharge in summer and autumn, respectively. Conversely, particulate MeHg prevailed when the river flow was low, especially at the estuary mouth (25.8 ± 19.1 pg L−1) and most likely due to the resuspension of fine particles promoted by a stronger tidal current. In comparison with the total Hg concentration, extremely low amounts of dissolved and particulate MeHg were observed, and strong interactions between MeHg and organic carbon highlighted a negligible risk of increased mobility and potential bioaccumulation of MeHg.
Collapse
|
14
|
Tercier-Waeber ML, Abdou M, Fighera M, Kowal J, Bakker E, van der Wal P. In Situ Voltammetric Sensor of Potentially Bioavailable Inorganic Mercury in Marine Aquatic Systems Based on Gel-Integrated Nanostructured Gold-Based Microelectrode Arrays. ACS Sens 2021; 6:925-937. [PMID: 33599131 DOI: 10.1021/acssensors.0c02111] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The development and field validation of newly designed nanostructured gold-plated gel-integrated microelectrode (Au-GIME) arrays applied to the direct in situ square wave anodic stripping voltammetry (SWASV) quantification of the potentially bioavailable inorganic mercury (Hg(II)) species in the coastal area are presented. The Au-GIME consists of arrays of 100-500 interconnected iridium (Ir)-based microdisks that are electroplated with renewable Au nanoparticles (AuNPs) or Au nanofilaments (AuNFs) and covered with an agarose gel. The gel protects the sensor surface from fouling and ensures that mass transport of analytes toward the sensor surface is by pure diffusion only and therefore independent of the ill-controlled convective conditions of the media. The responses of these sensors to direct SWASV measurements of inorganic Hg(II) at near-neutral pH were investigated first in synthetic media and then in UV-irradiated marine samples. The analytical responses were found to be correlated to the number of interconnected microelectrodes and the morphology of the nanostructured Au deposits and independent of the media composition for chloride concentration ≥0.2 M (salinity S ≥ 13) and pH ranging from 7 to 8.5. The AuNF-GIMEs have detection and quantification limits at a low pM level, fulfilling the requirement of sentinel tools for real-time monitoring of the dynamic fraction of Hg(II) in coastal area. The AuNF-GIMEs were incorporated in an in-house advanced multichannel sensing probe for remote in situ high-resolution trace metal monitoring. Field evaluation and validation were successfully performed as a part of a field study in Arcachon Bay (France), from which environmental data are presented. This work marks the first time that an autonomous electrochemical sensing probe successfully measures Hg(II) and its hourly temporal variation in situ without chemical modification of the sample.
Collapse
Affiliation(s)
- Mary-Lou Tercier-Waeber
- Department of Inorganic and Analytical Chemistry, University of Geneva, 1211 Geneva 4, Switzerland
| | - Melina Abdou
- Department of Inorganic and Analytical Chemistry, University of Geneva, 1211 Geneva 4, Switzerland
| | - Marianna Fighera
- Ecole Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel 2, Switzerland
| | - Justyna Kowal
- Department of Inorganic and Analytical Chemistry, University of Geneva, 1211 Geneva 4, Switzerland
| | - Eric Bakker
- Department of Inorganic and Analytical Chemistry, University of Geneva, 1211 Geneva 4, Switzerland
| | - Peter van der Wal
- Ecole Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel 2, Switzerland
| |
Collapse
|
15
|
Novo JP, Martins B, Raposo RS, Pereira FC, Oriá RB, Malva JO, Fontes-Ribeiro C. Cellular and Molecular Mechanisms Mediating Methylmercury Neurotoxicity and Neuroinflammation. Int J Mol Sci 2021; 22:ijms22063101. [PMID: 33803585 PMCID: PMC8003103 DOI: 10.3390/ijms22063101] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/06/2021] [Accepted: 03/15/2021] [Indexed: 02/06/2023] Open
Abstract
Methylmercury (MeHg) toxicity is a major environmental concern. In the aquatic reservoir, MeHg bioaccumulates along the food chain until it is consumed by riverine populations. There has been much interest in the neurotoxicity of MeHg due to recent environmental disasters. Studies have also addressed the implications of long-term MeHg exposure for humans. The central nervous system is particularly susceptible to the deleterious effects of MeHg, as evidenced by clinical symptoms and histopathological changes in poisoned humans. In vitro and in vivo studies have been crucial in deciphering the molecular mechanisms underlying MeHg-induced neurotoxicity. A collection of cellular and molecular alterations including cytokine release, oxidative stress, mitochondrial dysfunction, Ca2+ and glutamate dyshomeostasis, and cell death mechanisms are important consequences of brain cells exposure to MeHg. The purpose of this review is to organize an overview of the mercury cycle and MeHg poisoning events and to summarize data from cellular, animal, and human studies focusing on MeHg effects in neurons and glial cells. This review proposes an up-to-date compendium that will serve as a starting point for further studies and a consultation reference of published studies.
Collapse
Affiliation(s)
- João P. Novo
- Institute for Clinical and Biomedical Research (iCBR), Center for Innovative Biomedicine and Biotechnology (CIBB), and Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal; (J.P.N.); (B.M.); (R.S.R.); (F.C.P.)
| | - Beatriz Martins
- Institute for Clinical and Biomedical Research (iCBR), Center for Innovative Biomedicine and Biotechnology (CIBB), and Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal; (J.P.N.); (B.M.); (R.S.R.); (F.C.P.)
| | - Ramon S. Raposo
- Institute for Clinical and Biomedical Research (iCBR), Center for Innovative Biomedicine and Biotechnology (CIBB), and Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal; (J.P.N.); (B.M.); (R.S.R.); (F.C.P.)
- Experimental Biology Core, University of Fortaleza, Health Sciences, Fortaleza 60110-001, Brazil
| | - Frederico C. Pereira
- Institute for Clinical and Biomedical Research (iCBR), Center for Innovative Biomedicine and Biotechnology (CIBB), and Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal; (J.P.N.); (B.M.); (R.S.R.); (F.C.P.)
| | - Reinaldo B. Oriá
- Laboratory of Tissue Healing, Ontogeny and Nutrition, Department of Morphology and Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza 60430-270, Brazil;
| | - João O. Malva
- Institute for Clinical and Biomedical Research (iCBR), Center for Innovative Biomedicine and Biotechnology (CIBB), and Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal; (J.P.N.); (B.M.); (R.S.R.); (F.C.P.)
- Correspondence: (J.O.M.); (C.F.-R.)
| | - Carlos Fontes-Ribeiro
- Institute for Clinical and Biomedical Research (iCBR), Center for Innovative Biomedicine and Biotechnology (CIBB), and Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal; (J.P.N.); (B.M.); (R.S.R.); (F.C.P.)
- Correspondence: (J.O.M.); (C.F.-R.)
| |
Collapse
|
16
|
Mao L, Liu X, Wang B, Lin C, Xin M, Zhang BT, Wu T, He M, Ouyang W. Occurrence and risk assessment of total mercury and methylmercury in surface seawater and sediments from the Jiaozhou Bay, Yellow Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 714:136539. [PMID: 31981874 DOI: 10.1016/j.scitotenv.2020.136539] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 01/03/2020] [Accepted: 01/03/2020] [Indexed: 06/10/2023]
Abstract
The Jiaozhou Bay is a semi-enclosed bay located in the middle of the Yellow Sea. Effluents from wastewater treatment plants have been carried into the bay, which has significantly increased the deposition of mercury. The spatial distributions of total mercury (THg) and methylmercury (MeHg) in dissolved state, in suspended matters of seawater and surface sediments at 26 locations inside the Jiaozhou Bay and five surrounding rivers in April 2018 were examined. The contents of THg and MeHg found along the eastern coast were higher than those found along the western coast, which indicated the impact of human activities (river input) on the Jiaozhou Bay. The partition coefficient (LogKd) was used to express the distribution relationships of THg and MeHg in suspended matters and dissolved state, and it was concluded that suspended matter was the main reservoir of mercury in Jiaozhou Bay seawater. The correlations between contents and physicochemical properties of seawater showed that THg and MeHg concentrations in seawater decreased with increasing salinity and pH. The effects of the mean grain diameter (MGD) and sediment organic matter (SOM) on the THg and MeHg in surface sediments were also discussed. Principal component analysis (PCA) was used to obtain the factors determining the methylation proportion in the surface sediments, indicating that the combination of human activities and natural processes affected the degree of methylation in the sediments. The spatial distribution of THg, MeHg and MeHg% was suggested to be disturbed by the interaction of natural processes and human activities (river input) by the correlation analysis of the corresponding pollutant concentrations among seawater and. Although the concentrations of THg and MeHg in seawater and sediments of the Jiaozhou Bay did not exceed the Chinese regulatory standards, the pollution levels of THg and MeHg were comparable to those in other bays in the world.
Collapse
Affiliation(s)
- Lulu Mao
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Xitao Liu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Baodong Wang
- The First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China
| | - Chunye Lin
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Ming Xin
- The First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China
| | - Bo-Tao Zhang
- College of Water Sciences, Beijing University, Beijing 100875, China
| | - Tingting Wu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Mengchang He
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Wei Ouyang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| |
Collapse
|
17
|
Lei P, Zhong H, Duan D, Pan K. A review on mercury biogeochemistry in mangrove sediments: Hotspots of methylmercury production? THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 680:140-150. [PMID: 31112813 DOI: 10.1016/j.scitotenv.2019.04.451] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 04/30/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Wetlands are highly productive and biologically diverse environments that provide numerous ecosystem services, but can also be sources of methylmercury (MeHg) production and export. Mangrove wetlands contribute up to 15% of the coastal sediment carbon storage and ~10% of the particulate terrestrial carbon exported to the ocean. Thus, mercury (Hg) methylation in mangrove sediments and subsequent MeHg output to adjacent waters could have a great impact on global Hg cycling. In this review, we provide a comprehensive analysis of the literature on worldwide Hg concentrations in mangrove ecosystems, and the results reveal that a large range of total Hg (THg) and MeHg concentrations is detected in mangrove systems. Then, we discuss the potential roles of organic matter (OM) in controlling the Hg biogeochemistry in mangrove sediments. The intense OM decomposition by anoxic reduction (e.g., sulfate reduction) drastically affects sediment chemistries, such as redox potential, pH, and sulfur speciation, all of which may have a great impact on MeHg production. While the outwelling of carbon from mangroves has been extensively examined, little is known about their roles in exporting MeHg to adjacent waters. Our understanding of Hg biogeochemical processes in mangrove systems is constrained by the limited MeHg data and a lack of in-depth studies on the Hg methylation potential in this ecologically important environment. More efforts are needed to gain better insights into the contributions mangrove wetlands to the global Hg cycle.
Collapse
Affiliation(s)
- Pei Lei
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China; State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210046, China
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210046, China; Environmental and Life Science Program (EnLS), Trent University, Peterborough, Ontario, Canada
| | - Dandan Duan
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Ke Pan
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.
| |
Collapse
|
18
|
La Colla NS, Botté SE, Marcovecchio JE. Mercury cycling and bioaccumulation in a changing coastal system: From water to aquatic organisms. MARINE POLLUTION BULLETIN 2019; 140:40-50. [PMID: 30803660 DOI: 10.1016/j.marpolbul.2018.12.051] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 11/14/2018] [Accepted: 12/27/2018] [Indexed: 06/09/2023]
Abstract
This study evaluated -for the first time- the occurrence and distribution of total Hg in abiotic (dissolved and particulate water fractions) and biotic (gills and muscle tissues of six commercial fish species) compartments within a South American coastal environment with anthropogenic pressure. This study dealt with environmental issues on developing countries which, as they are in continuous growth, face the highest rate of coastal transformation. Total Hg content was determined by acid digestion and measured using a cold vapor atomic absorption spectrophotometer. Results revealed that dissolved Hg exceeded the recommended levels for superficial saline waters in 67% of the cases. Hg concentrations varied among fish species and its tissues. The results suggested that metal burden in fishes achieved a mean maximum accumulation towards the muscle, with concentrations below the international maximum permitted values. The estimated daily intakes calculated suggest that people would not experience significant health risks through fish consumption.
Collapse
Affiliation(s)
- Noelia S La Colla
- Instituto Argentino de Oceanografía (IADO - CONICET/UNS), Carrindanga km. 7.5, Bahía Blanca, 8000, Argentina.
| | - Sandra E Botté
- Instituto Argentino de Oceanografía (IADO - CONICET/UNS), Carrindanga km. 7.5, Bahía Blanca, 8000, Argentina; Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, Bahía Blanca 8000, Argentina.
| | - Jorge E Marcovecchio
- Instituto Argentino de Oceanografía (IADO - CONICET/UNS), Carrindanga km. 7.5, Bahía Blanca, 8000, Argentina; Universidad de la Fraternidad de Agrupaciones Santo Tomás de Aquino, Gascón 3145, Mar del Plata 7600, Argentina; Universidad Tecnológica Nacional - FRBB, 11 de Abril 445, Bahía Blanca 8000, Argentina.
| |
Collapse
|