1
|
Mir Y, Wu S, Ma M, Ran Y, Zhu K, Mangwandi C, Mirza ZA. Mercury contamination in the riparian ecosystem during the reservoir discharging regulated by a mega dam. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2022; 44:4405-4422. [PMID: 35089477 DOI: 10.1007/s10653-022-01205-z] [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: 08/25/2020] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
Mercury (Hg) is extremely poisonous and can be absorbed through touch, inhalation, or consumption. In the living environment, Hg in contaminated sediment can be transferred into grass by the direct absorption through the roots or shoots. The intake of Hg due to Hg emissions may pose a threat to living bodies especially to human beings. The present study aims to provide a novel insight about total mercury (THg) and methyl mercury (MeHg) in a riparian grass (Cynodon dactylon (L).Pers) and sediments during the discharging phase (summertime at 145 m water level) in Three Gorges Reservoir (TGR-China); where C. dactylon is a dominant perennial herb in the riparian zone. Yet, the potential risk of Hg contamination in the riparian ecosystem is not thoroughly assessed in the dam regulated reservoir. This study was conducted in the riparian zones of the reservoir formed by a mega dam (Three Gorge Dam) which regulates the water levels during the summer and winter period in the TGR. Our results showed that riparian sediments were acting as a sink for THg and MeHg. Insignificant correlation of THg and MeHg was found between the amphiphyte C. dactylon and its surrounding sediments in the TGR. Bioconcentration factors values for MeHg were found higher than 1 in all study locations in the riparian zones in TGR, which could be due to action of certain bacteria/purely chemical-based methylation on inorganic form of Hg. Additionally, translocation factor indices also highlighted that the amphiphyte C. dactylon was MeHg accumulator in riparian zones. These results suggested that since riparian sediment was found acting as the sink for THg and MeHg during discharging phase, MeHg contamination in the amphiphyte C. dactylon in riparian zones was not caused by the riparian sediments but by other factors, for instance, the anthropogenic activities in the TGR. Finally, this study leads to conclude that amphiphyte C. dactylon can be used as biomonitoring agent for Hg pollution in the TGR.
Collapse
Affiliation(s)
- Yaseen Mir
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shengjun Wu
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
| | - Maohua Ma
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
| | - Yiguo Ran
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kai Zhu
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
| | - Chirangano Mangwandi
- School of Chemistry and Chemical Engineering, David Kier Building Queen's University Belfast, Belfast, BT95AG, UK
| | - Zakaria Ahmed Mirza
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China.
| |
Collapse
|
2
|
Iordache AM, Nechita C, Zgavarogea R, Voica C, Varlam M, Ionete RE. Accumulation and ecotoxicological risk assessment of heavy metals in surface sediments of the Olt River, Romania. Sci Rep 2022; 12:880. [PMID: 35042928 PMCID: PMC8766583 DOI: 10.1038/s41598-022-04865-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 12/31/2021] [Indexed: 01/30/2023] Open
Abstract
Heavy metal pollution of river freshwater environments currently raises significant concerns due to the toxic effects and the fact that heavy metal behavior is not fully understood. This study assessed the contamination level of eight heavy metals and trace elements (Cr, Ni, Cu, Zn, As, Pb, Cd, and Hg) in the surface sediments of 19 sites in 2018 during four periods (March, May, June, and October) in Olt River sediments. Multivariate statistical techniques were used, namely, one-way ANOVA, person product-moment correlation analysis, principal component analysis, hierarchical cluster analysis, and sediment quality indicators such as the contamination factor and pollution load index. The results demonstrated higher contents of Ni, Cu, Zn, As, Pb, Cd, and Hg, with values that were over 2.46, 4.40, 1.15, 8.28, 1.10, 1.53, and 3.71 times more, respectively, compared with the national quality standards for sediments. We observed a positive significant statistical correlation (p < 0.001) in March between elevation and Pb, Ni, Cu, Cr, and Zn and a negative correlation between Pb and elevation (p = 0.08). Intermetal associations were observed only in March, indicating a relationship with river discharge from spring. The PCA sustained mainly anthropogenic sources of heavy metals, which were also identified through correlation and cluster analyses. We noted significant differences between the Cr and Pb population means and variances (p < 0.001) for the data measured in March, May, June, and October. The contamination factor indicated that the pollution level of heavy metals was high and significant for As at 15 of the 19 sites. The pollution load index showed that over 89% of the sites were polluted by metals to various degrees during the four periods investigated. Our results improve the knowledge of anthropogenic versus natural origins of heavy metals in river surface sediments, which is extremely important in assessing environmental and human health risks and beneficial for decision-maker outcomes for national freshwater management plans.
Collapse
Affiliation(s)
- Andreea Maria Iordache
- National Research and Development Institute for Cryogenics and Isotopic Technologies-ICSI Rm. Valcea, 4 Uzinei Street, 240050 Rm. Valcea, Valcea, Romania.
| | - Constantin Nechita
- National Institute for Research and Development in Forestry "Marin Drăcea" Calea Bucovinei, 73 bis, 725100, Câmpulung Moldovenesc, Romania.
| | - Ramona Zgavarogea
- National Research and Development Institute for Cryogenics and Isotopic Technologies-ICSI Rm. Valcea, 4 Uzinei Street, 240050 Rm. Valcea, Valcea, Romania
| | - Cezara Voica
- National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat St, 400293, Cluj-Napoca, Romania
| | - Mihai Varlam
- National Research and Development Institute for Cryogenics and Isotopic Technologies-ICSI Rm. Valcea, 4 Uzinei Street, 240050 Rm. Valcea, Valcea, Romania
| | - Roxana Elena Ionete
- National Research and Development Institute for Cryogenics and Isotopic Technologies-ICSI Rm. Valcea, 4 Uzinei Street, 240050 Rm. Valcea, Valcea, Romania
| |
Collapse
|
3
|
Assessment of Distribution of Potentially Toxic Elements in Different Environmental Media Impacted by a Former Chlor-Alkali Plant. SUSTAINABILITY 2021. [DOI: 10.3390/su132413829] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Former industrially contaminated sites are a burden from the past that still pose environmental risks. During the second half of the 20th century, the Pavlodar region in North Kazakhstan had been a part of Soviet Union’s industrial system that operated a chlor-alkali plant (CAP). The former CAP discharged approximately 135 t Hg into nearby Lake Balkyldak with total losses to water, soil, and air estimated around 1000 t. Pollution by potentially toxic elements (PTEs) due to former and currently active industrial enterprises is an under-investigated concern in the Pavlodar region. The present study aims to provide a much-needed update on the situation around the CAP area by evaluating the contamination by Hg and other selected PTEs (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Zn) on the surrounding environment of the CAP and in the nearby urban zone. Soil, sediment, surface water, and groundwater samples have been collected in several sampling campaigns carried out in 2018 and 2019. Several samples had Hg concentrations exceeding maximum permissible concentrations (MPC), for soils and sediments (in mg/kg; range: 0.0006 to 24, average: 0.56) and for surface water and groundwater (in µg/L; range: 0.004 to 1340, average: 93). Critically high concentrations were mostly measured in the vicinity of Lake Balkyldak, where the majority of Hg had been discharged by the former CAP, indicating persisting Hg pollution in the studied zone. A comparison of the PTEs concentrations in soil and sediments showed less severe pollution but still some elevated values for As, Ba, Co, Cu, Mn, Ni, and Se. The inter-elemental relationship between Hg and assessed PTEs was weak, indicating the presence of sources independent from Hg emitting sources. Further research on Hg contamination on the exact territory of the former CAP is needed, and a detailed human health risk characterization to identify potential unacceptable risks is strongly recommended.
Collapse
|
4
|
Iordache AM, Nechita C, Pluhacek T, Iordache M, Zgavarogea R, Ionete RE. Past and present anthropic environmental stress reflect high susceptibility of natural freshwater ecosystems in Romania. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 267:115505. [PMID: 32892015 DOI: 10.1016/j.envpol.2020.115505] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 08/11/2020] [Accepted: 08/21/2020] [Indexed: 06/11/2023]
Abstract
The concentrations of twelve heavy metals and trace elements (Cr, Mn, Co, Ni, Cu, As, Cd, Pb, Hg, Zn, Fe, and Al) in bed sediment and river freshwater that received sewage discharge, industrial wastewater inputs and mining residue were discussed. Spatial distribution, intra-annual trends and diffuse flux in 2019 in the middle and lower reaches of Olt River Basin (ORB) were investigated using inductively coupled mass spectrometry (ICP-MS) and atomic absorption spectroscopy (AAS). We applied correlation and principal component analysis (PCA) to quantify metal distribution relationship within environmental factors (pH, air temperature) and organic matter existing in the ORB. Moreover, the 87Sr/86Sr and 206Pb/207Pb isotope ratios analysis was employed to conclude the possible origin of the contamination. PCA analysis categorized metal presence in the four-component model, which explains 91% (May), 92% (July) and 93% (September) of the variance and indicates the potential origins of pollutants. The HCA and correlation analysis emphasized the relationship between trace elements, heavy metals in water and sediments and physicochemical characteristics of water. It was observed a high discrepancy in metal distribution between riverbed sediments and water body. In September, correlation indices highlighted sparse positive relationship with trace elements in water and mainly negative correlation values with trace elements from sediments. The origin of pollutants in sediments and water appear to be both natural and human-related activities. In all seasons increased the total exchangeable concentration of Ni, Cu and Zn in the sediments downstream sewage treatment plants and upstream of dams. The consideration of environmental factors and physicochemical characteristics of water is required to develop strategies for pollution management, assessment and mitigation in the actual condition of climate change. This study evaluated the heavy metals pollution in the Olt River Basin over three periods in 2019 under human-induced changes.
Collapse
Affiliation(s)
- Andreea Maria Iordache
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm, Valcea, 4 Uzinei Street, 240050, Rm. Valcea, Valcea, Romania
| | - Constantin Nechita
- National Research and Development Institute for Forestry "Marin Drăcea" Calea Bucovinei, 73 Bis, 725100, Câmpulung Moldovenesc, Romania.
| | - Tomas Pluhacek
- Department of Analytical Chemistry, Faculty of Science, Palacky University, 17 Listopadu 12, Olomouc, CZ-771 46, Czech Republic
| | - Mihaela Iordache
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm, Valcea, 4 Uzinei Street, 240050, Rm. Valcea, Valcea, Romania
| | - Ramona Zgavarogea
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm, Valcea, 4 Uzinei Street, 240050, Rm. Valcea, Valcea, Romania
| | - Roxana Elena Ionete
- National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm, Valcea, 4 Uzinei Street, 240050, Rm. Valcea, Valcea, Romania
| |
Collapse
|
5
|
Guney M, Akimzhanova Z, Kumisbek A, Beisova K, Kismelyeva S, Satayeva A, Inglezakis V, Karaca F. Mercury (Hg) Contaminated Sites in Kazakhstan: Review of Current Cases and Site Remediation Responses. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E8936. [PMID: 33271828 PMCID: PMC7730887 DOI: 10.3390/ijerph17238936] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/26/2020] [Accepted: 11/27/2020] [Indexed: 01/06/2023]
Abstract
Mercury (Hg) emissions from anthropogenic sources pose a global problem. In Central Asia, Kazakhstan's central and northern regions are among the most severely Hg-contaminated territories. This is due to two former acetaldehyde (in Temirtau) and chlor-alkali (in Pavlodar) plants, discharges from which during the second half of the 20th century were estimated over 2000 tons of elemental Hg. However, the exact quantities of Hg released through atmospheric emissions to the environment, controlled discharges to the nearby aquatic systems, leakages in the cell plant, and contaminated sludge are still unknown. The present review is the initiation of a comprehensive field investigation study on the current state of these contaminated sites. It aims to provide a critical review of published literature on Hg in soils, sediments, water, and biota of the impacted ecosystems (Nura and Irtysh rivers, and Lake Balkyldak and their surrounding areas). It furthermore compares these contamination episodes with selected similar international cases as well as reviews and recommends demercuration efforts. The findings indicate that the contamination around the acetaldehyde plant site was significant and mainly localized with the majority of Hg deposited in topsoils and riverbanks within 25 km from the discharge point. In the chlor-alkali plant site, Lake Balkyldak in North Kazakhstan is the most seriously contaminated receptor. The local population of both regions might still be exposed to Hg due to fish consumption illegally caught from local rivers and reservoirs. Since the present field data is limited mainly to investigations conducted before 2010 and given the persisting contamination and nature of Hg, a recent up-to-date environmental assessment for both sites is highly needed, particularly around formerly detected hotspots. Due to incomplete site remediation efforts, recommendations given by several researchers for the territories of the former chlor-alkali and acetaldehyde plant site include ex-situ soil washing, soil pulping with gravitational separation, ultrasound and transgenic algae for sediments, and electrokinetic recovery for the former and removal and/or confinement of contaminated silt deposits and soils for the latter. However, their efficiency first needs to be validated. Findings and lessons from these sites will be useful not only on the local scale but also are valuable resources for the assessment and management of similar contaminated sites around the globe.
Collapse
Affiliation(s)
- Mert Guney
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Nur-Sultan 010000, Kazakhstan; (Z.A.); (A.K.); (K.B.); (S.K.); (A.S.); (F.K.)
- Environmental Science & Technology Group (ESTg), Department of Civil and Environmental Engineering, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
| | - Zhanel Akimzhanova
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Nur-Sultan 010000, Kazakhstan; (Z.A.); (A.K.); (K.B.); (S.K.); (A.S.); (F.K.)
- Environmental Science & Technology Group (ESTg), Department of Civil and Environmental Engineering, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
| | - Aiganym Kumisbek
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Nur-Sultan 010000, Kazakhstan; (Z.A.); (A.K.); (K.B.); (S.K.); (A.S.); (F.K.)
- Environmental Science & Technology Group (ESTg), Department of Civil and Environmental Engineering, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
| | - Kamila Beisova
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Nur-Sultan 010000, Kazakhstan; (Z.A.); (A.K.); (K.B.); (S.K.); (A.S.); (F.K.)
- Environmental Science & Technology Group (ESTg), Department of Civil and Environmental Engineering, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
| | - Symbat Kismelyeva
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Nur-Sultan 010000, Kazakhstan; (Z.A.); (A.K.); (K.B.); (S.K.); (A.S.); (F.K.)
- Environmental Science & Technology Group (ESTg), Department of Civil and Environmental Engineering, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
| | - Aliya Satayeva
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Nur-Sultan 010000, Kazakhstan; (Z.A.); (A.K.); (K.B.); (S.K.); (A.S.); (F.K.)
- Environmental Science & Technology Group (ESTg), Department of Chemical and Materials Engineering, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
| | - Vassilis Inglezakis
- Chemical and Process Engineering, University of Strathclyde, Glasgow G1 1XQ, UK;
| | - Ferhat Karaca
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Nur-Sultan 010000, Kazakhstan; (Z.A.); (A.K.); (K.B.); (S.K.); (A.S.); (F.K.)
- Environmental Science & Technology Group (ESTg), Department of Civil and Environmental Engineering, Nazarbayev University, Nur-Sultan 010000, Kazakhstan
| |
Collapse
|
6
|
Palanques A, Guillén J, Puig P, Grimalt JO. Effects of flushing flows on the transport of mercury-polluted particulate matter from the Flix Reservoir to the Ebro Estuary. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 260:110028. [PMID: 31941623 DOI: 10.1016/j.jenvman.2019.110028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/17/2019] [Accepted: 12/21/2019] [Indexed: 06/10/2023]
Abstract
Polluted sediments retained in water reservoirs are potential sources of deleterious materials downstream, especially during floods or flushing flows (FFs). Their interaction with these events is important for determining potential risks and evaluating management actions. In the Ebro River, the Flix Reservoir accumulated a deposit of more than 3 × 105 t of industrial waste with high Hg concentrations. Because suspended particulate matter (SPM) is the main driver of Hg pollution downriver, this study analyses the transport of particulate matter and Hg pollution from the Flix Reservoir to the Ebro Estuary during FFs. Time series of currents, turbidity and downward particulate matter fluxes were obtained by current meters, turbidimeters and sediment traps assembled in benthic tripods. They were deployed in the reservoir and at two locations in the estuary during two recording periods that each captured a flushing flow (FF) event. In addition, SPM samples were collected during the study period at several locations along the river course, from upstream of the Flix Reservoir down to the river mouth, to measure the suspended particulate matter and associated Hg mobilized downstream. A continuous background level of Hg pollution was observed during the deployment periods, but the Hg and particulate matter fluxes increased by between one and two orders of magnitude during FFs. Though the two events reached similar water discharges, the first FF was after the wet season and generated lower particulate matter concentrations and fluxes, but higher Hg contents than the second, which occurred after the dry season. The higher available particulate matter in the second event diluted the polluted Hg particle load more than the first event. Thus, similar FFs may result in different Hg concentration and sediment transport episodes, largely depending on the previous hydrological regime and the river sediment availability. These findings should be considered for FF management.
Collapse
Affiliation(s)
- Albert Palanques
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona, 08003, Spain.
| | - Jorge Guillén
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona, 08003, Spain
| | - Pere Puig
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona, 08003, Spain
| | - Joan O Grimalt
- Institute of Environmental Assessment and Water Research (CSIC), Jordi Girona, 18, Barcelona, 08034, Spain
| |
Collapse
|
7
|
Varol M, Canpolat Ö, Eriş KK, Çağlar M. Trace metals in core sediments from a deep lake in eastern Turkey: Vertical concentration profiles, eco-environmental risks and possible sources. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 189:110060. [PMID: 31821939 DOI: 10.1016/j.ecoenv.2019.110060] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/28/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
The contents of 12 trace metals (Hg, As, Pb, Cd, Ni, Cr, Zn, Cu, Co, Mn, Al and Fe) in two sediment cores (Hz11-P02 and Hz11-P09) from the Lake Hazar, one of the deepest natural lakes in Turkey, were examined to evaluate vertical concentration profiles, possible sources, pollution status and eco-environmental risks of these metals. The highest concentrations of Cd and As were detected in the upper part (0-10 cm depths) of core Hz11-P02, while Hg concentration was at a maximum in the upper part of core Hz11-P09. The concentrations of other metals except Cr were the highest in the bottom layer (depths below 100 cm) of both cores. Among trace metals (TMs), Cr, Ni, Al and Mn in core Hz11-P02 and Mn in core Hz11-P09 showed statistically significant correlations with core depth (p < 0.01). The mean concentrations of Hg, Pb, Cd, Cu, Zn, Co, Mn, Al and Fe in core Hz11-P02 were significantly higher than those in core Hz11-P09 (p < 0.01). Also, the mean enrichment factor, geoaccumulation index and contamination factor values of As, Cu, Cd, Zn, Pb and Hg were higher in core Hz11-P02. The ecological risk index (RI) values for core Hz11-P02 were between 150 and 300 in 40.3% of the samples, indicating "moderate ecological risk", whereas the RI values for core Hz11-P09 were <150 in 100% of the samples, indicating "low ecological risk". Factor, cluster and correlation analyses, and contamination indices indicated that As and Hg in core Hz11-P02 predominantly originated from anthropogenic sources, while 12 trace metals in core Hz11-P09 derived from natural sources.
Collapse
Affiliation(s)
- Memet Varol
- Malatya Turgut Özal University, Faculty of Fisheries, Malatya, Turkey.
| | | | - Kürşad Kadir Eriş
- İTÜ EMCOL and Geological Engineering Department, Faculty of Mining, İstanbul, Turkey
| | - Metin Çağlar
- Fırat University, Faculty of Fisheries, Elazığ, Turkey
| |
Collapse
|
8
|
Hsu-Kim H, Eckley CS, Achá D, Feng X, Gilmour CC, Jonsson S, Mitchell CPJ. Challenges and opportunities for managing aquatic mercury pollution in altered landscapes. AMBIO 2018; 47:141-169. [PMID: 29388127 PMCID: PMC5794684 DOI: 10.1007/s13280-017-1006-7] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The environmental cycling of mercury (Hg) can be affected by natural and anthropogenic perturbations. Of particular concern is how these disruptions increase mobilization of Hg from sites and alter the formation of monomethylmercury (MeHg), a bioaccumulative form of Hg for humans and wildlife. The scientific community has made significant advances in recent years in understanding the processes contributing to the risk of MeHg in the environment. The objective of this paper is to synthesize the scientific understanding of how Hg cycling in the aquatic environment is influenced by landscape perturbations at the local scale, perturbations that include watershed loadings, deforestation, reservoir and wetland creation, rice production, urbanization, mining and industrial point source pollution, and remediation. We focus on the major challenges associated with each type of alteration, as well as management opportunities that could lessen both MeHg levels in biota and exposure to humans. For example, our understanding of approximate response times to changes in Hg inputs from various sources or landscape alterations could lead to policies that prioritize the avoidance of certain activities in the most vulnerable systems and sequestration of Hg in deep soil and sediment pools. The remediation of Hg pollution from historical mining and other industries is shifting towards in situ technologies that could be less disruptive and less costly than conventional approaches. Contemporary artisanal gold mining has well-documented impacts with respect to Hg; however, significant social and political challenges remain in implementing effective policies to minimize Hg use. Much remains to be learned as we strive towards the meaningful application of our understanding for stakeholders, including communities living near Hg-polluted sites, environmental policy makers, and scientists and engineers tasked with developing watershed management solutions. Site-specific assessments of MeHg exposure risk will require new methods to predict the impacts of anthropogenic perturbations and an understanding of the complexity of Hg cycling at the local scale.
Collapse
Affiliation(s)
- Heileen Hsu-Kim
- Department of Civil & Environmental Engineering, Duke University, 121 Hudson Hall, Box 90287, Durham, NC 27708 USA
| | - Chris S. Eckley
- U.S. Environmental Protection Agency, Region-10, 1200 6th Ave, Seattle, WA 98101 USA
| | - Dario Achá
- Unidad de Calidad Ambiental, Instituto de Ecología, Carrera de Biología, Universidad Mayor de San Andrés, P.O. Box 10077, La Paz, Bolivia
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002 China
| | - Cynthia C. Gilmour
- Smithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD 21037-0028 USA
| | - Sofi Jonsson
- Department of Environmental Science and Analytical Chemistry, Stockholm University, Svante Arrhenius väg 8, 11418 Stockholm, Sweden
| | - Carl P. J. Mitchell
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C 1A4 Canada
| |
Collapse
|
9
|
Dranguet P, Cosio C, Le Faucheur S, Beauvais-Flück R, Freiburghaus A, Worms IAM, Petit B, Civic N, Docquier M, Slaveykova VI. Transcriptomic approach for assessment of the impact on microalga and macrophyte of in-situ exposure in river sites contaminated by chlor-alkali plant effluents. WATER RESEARCH 2017; 121:86-94. [PMID: 28521238 DOI: 10.1016/j.watres.2017.05.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 05/02/2017] [Accepted: 05/08/2017] [Indexed: 06/07/2023]
Abstract
Water quality degradation is a worldwide problem, but risk evaluation of chronic pollution in-situ is still a challenge. The present study aimed to evaluate the potential of transcriptomic analyses in representative aquatic primary producers to assess the impact of environmental pollution in-situ: the microalga Chlamydomonas reinhardtii and the macrophyte Elodea nuttallii were exposed 2 h in the Babeni Reservoir of the Olt River impacted by chlor-alkali plant effluent release resulting in increased concentrations of Hg and NaCl in receiving water. The response at the transcriptomic level was strong, resulting in up to 5485, and 8700 dysregulated genes (DG) for the microalga and for the macrophyte exposed in the most contaminated site, respectively. Transcriptomic response was congruent with the concentrations of Hg and NaCl in the water of the impacted reservoir. Genes involved in development, energy metabolism, lipid metabolism, nutrition, and RedOx homeostasis were dysregulated during in-situ exposure of both organisms. In addition, genes involved in the cell motility of C. reinhardtii and development of the cell wall of E. nuttallii were affected. DG were in line with adverse outcome pathways and transcriptomic studies reported after exposure to high concentrations of Hg and NaCl under controlled conditions in the laboratory. Transcriptomic response provided a sensitive measurement of the exposure as well as hints on the tolerance mechanisms of environmental pollution, and is thus promising as an early-warning tool to assess water quality degradation.
Collapse
Affiliation(s)
- Perrine Dranguet
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environment Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, 66 Bvd. Carl-Vogt, 1211 Geneva 4, Switzerland
| | - Claudia Cosio
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environment Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, 66 Bvd. Carl-Vogt, 1211 Geneva 4, Switzerland.
| | - Séverine Le Faucheur
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environment Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, 66 Bvd. Carl-Vogt, 1211 Geneva 4, Switzerland
| | - Rebecca Beauvais-Flück
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environment Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, 66 Bvd. Carl-Vogt, 1211 Geneva 4, Switzerland
| | - Aline Freiburghaus
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environment Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, 66 Bvd. Carl-Vogt, 1211 Geneva 4, Switzerland
| | - Isabelle A M Worms
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environment Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, 66 Bvd. Carl-Vogt, 1211 Geneva 4, Switzerland
| | - Brice Petit
- iGE3 Genomics Platform, University of Geneva Medical School - CMU, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Natacha Civic
- iGE3 Genomics Platform, University of Geneva Medical School - CMU, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Mylène Docquier
- iGE3 Genomics Platform, University of Geneva Medical School - CMU, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Vera I Slaveykova
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environment Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, 66 Bvd. Carl-Vogt, 1211 Geneva 4, Switzerland.
| |
Collapse
|
10
|
Dranguet P, Cosio C, Le Faucheur S, Hug Peter D, Loizeau JL, Ungureanu VG, Slaveykova VI. Biofilm composition in the Olt River (Romania) reservoirs impacted by a chlor-alkali production plant. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2017; 19:687-695. [PMID: 28379244 DOI: 10.1039/c7em00033b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Freshwater biofilms can be useful indicators of water quality and offer the possibility to assess contaminant effects at the community level. The present field study examines the effects of chlor-alkali plant effluents on the community composition of biofilms grown in the Olt River (Romania) reservoirs. The relationship between ambient water quality variables and community composition alterations was explored. Amplicon sequencing revealed a significant modification of the composition of microalgal, bacterial and fungal communities in the biofilms collected in the impacted reservoirs in comparison with those living in the uncontaminated control reservoir. The abundance corrected Simpson index showed lower richness and diversity in biofilms collected in the impacted reservoirs than in the control reservoir. The biofilm bacterial communities of the impacted reservoirs were characterized by the contaminant-tolerant Cyanobacteria and Bacteroidetes, whereas microalgal communities were predominantly composed of Bacillariophyta and fungal communities of Lecanoromycetes and Paraglomycetes. A principal component analysis revealed that major contaminants present in the waste water of the chlor-alkali production plant, i.e. Na+, Ca2+, Cl- and Hg, were correlated with the alteration of biofilm community composition in the impacted reservoirs. However, the biofilm composition was also influenced by water quality variables such as NO3-, SO42-, DOC and Zn from unknown sources. The results of the present study imply that, even when below the environmental quality standards, typical contaminants of chlor-alkali plant releases may affect biofilm composition and that their impacts on the microbial biodiversity might be currently overlooked.
Collapse
Affiliation(s)
- P Dranguet
- University of Geneva, Faculty of Sciences, Earth and Environmental Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Uni Carl Vogt, 66 Bvd. Carl Vogt, CH-1211, Geneva, Switzerland.
| | | | | | | | | | | | | |
Collapse
|
11
|
Navrátil T, Šimeček M, Shanley JB, Rohovec J, Hojdová M, Houška J. The history of mercury pollution near the Spolana chlor-alkali plant (Neratovice, Czech Republic) as recorded by Scots pine tree rings and other bioindicators. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 586:1182-1192. [PMID: 28237461 DOI: 10.1016/j.scitotenv.2017.02.112] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 02/13/2017] [Accepted: 02/13/2017] [Indexed: 05/21/2023]
Abstract
We assessed >100years of mercury (Hg) pollution recorded in the tree rings of Scots Pine near a Czech chlor-alkali plant operating since 1941. Hg concentrations in tree rings increased with the launching of plant operations and decreased when Hg emissions decreased in 1975 due to an upgrade in production technology. Similar to traditional bioindicators of pollution such as pine needles, bark and forest floor humus, Hg concentrations in Scots Pine boles decreased with distance from the plant. Mean Hg in pine bole in the 1940s ranged from 32.5μg/kg Hg at a distance of 0.5km from the plant to 5.4μg/kg at a distance of >4.7km, where tree ring Hg was the same as at a reference site, and other bioindicators also suggest that the effect of the plant was no longer discernible. Tree ring Hg concentrations decreased by 8-29μg/kg since the 1940s at all study sites including the reference site. The lack of exact correspondence between changes at the plant and tree ring Hg indicated some smearing of the signal due to lateral translocation of Hg from sapwood to heartwood. Bole Hg concentrations reflected local and regional atmospheric Hg concentrations, and not Hg wet deposition.
Collapse
Affiliation(s)
- Tomáš Navrátil
- Institute of Geology of CAS, v.v.i., Rozvojová 269, 165 00 Prague 6, Czech Republic.
| | - Martin Šimeček
- Institute of Geology of CAS, v.v.i., Rozvojová 269, 165 00 Prague 6, Czech Republic
| | | | - Jan Rohovec
- Institute of Geology of CAS, v.v.i., Rozvojová 269, 165 00 Prague 6, Czech Republic
| | - Maria Hojdová
- Institute of Geology of CAS, v.v.i., Rozvojová 269, 165 00 Prague 6, Czech Republic
| | - Jakub Houška
- Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamýcká 129, 165 21 Prague 6, Czech Republic
| |
Collapse
|
12
|
Dranguet P, Le Faucheur S, Cosio C, Slaveykova VI. Influence of chemical speciation and biofilm composition on mercury accumulation by freshwater biofilms. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2017; 19:38-49. [PMID: 27942649 DOI: 10.1039/c6em00493h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Mercury (Hg) is a pollutant of high concern for aquatic systems due to the biomagnification of its methylated form along the food chain. However, in contrast to other metals, gaining knowledge of its bioavailable forms for aquatic microorganisms remains challenging, making Hg risk assessment difficult. Ubiquitous and sessile freshwater biofilms are well known to accumulate and to transform Hg present in their ambient environment. The present study thus aims to evaluate whether non-extractable (proxy of intracellular) Hg accumulated by biofilms could be a good indicator of Hg bioavailability for microorganisms in freshwater. To that end, the link between Hg concentration and speciation, as well as biofilm composition (percentage of abiotic, biotic, chlorophyll and phycocyanin-fractions and abundance of dsrA, gcs, merA and hgcA bacterial genes) and biofilm Hg accumulation was examined. The studied biofilms were grown on artificial substrata in four reservoirs along the Olt River (Romania), which was contaminated by Hg coming from chlor-alkali plant effluents. The 0.45 μm-filterable Hg concentrations in ambient waters were measured and inorganic IHg speciation was modelled. Biofilms were analyzed for their non-extractable IHg and methylmercury (MeHg) contents as well as for their composition. The non-extractable IHg content was related, but not significantly, to the concentration of total IHg (r2 = 0.88, p = 0.061) whereas a significant correlation was found with the predicted IHg concentration that is not bound to dissolved organic matter (r2 = 0.95, p = 0.027), despite its extremely low concentrations (10-25 M), showing a limitation of the thermodynamic Hg modelling to predict Hg bioavailability. The studied biofilms were different in biomass and composition and a principal component analysis showed that the non-extractable IHg content correlated with the abundance of the merA and hgcA genes, while MeHg accumulation was only linked with the abundance of the rRNA 16S gene. The present study suggests that non-extractable IHg concentrations in biofilms are a useful proxy of IHg bioavailable forms in waters whereas the hgcA and merA genes are good biomarkers of both biofilm IHg exposure and bioavailability.
Collapse
Affiliation(s)
- P Dranguet
- University of Geneva, Faculty of Science, Earth and Environmental Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Uni Carl Vogt, 66 Bvd. Carl Vogt, CH-1211 Geneva, Switzerland.
| | - S Le Faucheur
- University of Geneva, Faculty of Science, Earth and Environmental Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Uni Carl Vogt, 66 Bvd. Carl Vogt, CH-1211 Geneva, Switzerland.
| | - C Cosio
- University of Geneva, Faculty of Science, Earth and Environmental Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Uni Carl Vogt, 66 Bvd. Carl Vogt, CH-1211 Geneva, Switzerland.
| | - V I Slaveykova
- University of Geneva, Faculty of Science, Earth and Environmental Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Uni Carl Vogt, 66 Bvd. Carl Vogt, CH-1211 Geneva, Switzerland.
| |
Collapse
|
13
|
Le Faucheur S, Vasiliu D, Catianis I, Zazu M, Dranguet P, Beauvais-Flück R, Loizeau JL, Cosio C, Ungureanu C, Ungureanu VG, Slaveykova VI. Environmental quality assessment of reservoirs impacted by Hg from chlor-alkali technologies: case study of a recovery. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:22542-22553. [PMID: 27557957 DOI: 10.1007/s11356-016-7405-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 08/04/2016] [Indexed: 06/06/2023]
Abstract
Mercury (Hg) pollution legacy of chlor-alkali plants will be an important issue in the next decades with the planned phase out of Hg-based electrodes by 2025 within the Minamata convention. In such a context, the present study aimed to examine the extent of Hg contamination in the reservoirs surrounding the Oltchim plant and to evaluate the possible improvement of the environmental quality since the closure of its chlor-alkali unit. This plant is the largest chlor-alkali plant in Romania, which partly switched to Hg-free technology in 1999 and definitely stopped the use of Hg electrolysis in May 2012. Total Hg (THg) and methylmercury (CH3Hg) concentrations were found to decrease in the surface waters and sediments of the reservoirs receiving the effluents of the chlor-alkali platform since the closure of Hg units. Hence, calculated risk quotients (RQ) indicated no adverse effect of Hg for aquatic organisms from the ambient water exposure. RQ of Hg in sediments were mostly all higher than 1, showing important risks for benthic organisms. However, ecotoxicity testing of water and sediments suggest possible impact of other contaminants and their mixtures. Hg hotspots were found in soils around the platform with RQ values much higher than 1. Finally, THg and CH3Hg concentrations in fish were below the food safety limit set by the WHO, which contrasts with previous measurements made in 2007 revealing that 92 % of the studied fish were of high risk of consumption. Discontinuing the use of Hg electrodes greatly improved the surrounding environment of chlor-alkali plants within the following years and led to the decrease environmental exposure to Hg through fish consumption. However, sediment and soil still remained highly contaminated and problematic for the river reservoir management. The results of this ecological risk assessment study have important implications for the evaluation of the benefits as well as limits of the Minamata Convention implementation.
Collapse
Affiliation(s)
- Séverine Le Faucheur
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Institute F.-A. Forel, Environmental Biogeochemistry and Ecotoxicology, Uni Carl Vogt, 66 Bvd Carl-Vogt, 1211, Geneva 4, Switzerland.
| | - Dan Vasiliu
- National Institute for Research and Development of Marine Geology and Geoecology (GeoEcoMar), 23-25 Dimitrie Onciul Street, 024053, Bucharest, Romania
| | - Irina Catianis
- National Institute for Research and Development of Marine Geology and Geoecology (GeoEcoMar), 23-25 Dimitrie Onciul Street, 024053, Bucharest, Romania
| | - Mariana Zazu
- National Institute for Research and Development of Marine Geology and Geoecology (GeoEcoMar), 23-25 Dimitrie Onciul Street, 024053, Bucharest, Romania
| | - Perrine Dranguet
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Institute F.-A. Forel, Environmental Biogeochemistry and Ecotoxicology, Uni Carl Vogt, 66 Bvd Carl-Vogt, 1211, Geneva 4, Switzerland
| | - Rebecca Beauvais-Flück
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Institute F.-A. Forel, Environmental Biogeochemistry and Ecotoxicology, Uni Carl Vogt, 66 Bvd Carl-Vogt, 1211, Geneva 4, Switzerland
| | - Jean-Luc Loizeau
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Institute F.-A. Forel, Environmental Biogeochemistry and Ecotoxicology, Uni Carl Vogt, 66 Bvd Carl-Vogt, 1211, Geneva 4, Switzerland
| | - Claudia Cosio
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Institute F.-A. Forel, Environmental Biogeochemistry and Ecotoxicology, Uni Carl Vogt, 66 Bvd Carl-Vogt, 1211, Geneva 4, Switzerland
| | - Costin Ungureanu
- National Institute for Research and Development of Marine Geology and Geoecology (GeoEcoMar), 23-25 Dimitrie Onciul Street, 024053, Bucharest, Romania
| | - Viorel Gheorghe Ungureanu
- National Institute for Research and Development of Marine Geology and Geoecology (GeoEcoMar), 23-25 Dimitrie Onciul Street, 024053, Bucharest, Romania
| | - Vera I Slaveykova
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Institute F.-A. Forel, Environmental Biogeochemistry and Ecotoxicology, Uni Carl Vogt, 66 Bvd Carl-Vogt, 1211, Geneva 4, Switzerland.
| |
Collapse
|
14
|
Bravo AG, Loizeau JL, Dranguet P, Makri S, Björn E, Ungureanu VG, Slaveykova VI, Cosio C. Persistent Hg contamination and occurrence of Hg-methylating transcript (hgcA) downstream of a chlor-alkali plant in the Olt River (Romania). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:10529-10541. [PMID: 26662302 DOI: 10.1007/s11356-015-5906-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 11/30/2015] [Indexed: 05/16/2023]
Abstract
Chlor-alkali plants using mercury (Hg) cell technology are acute point sources of Hg pollution in the aquatic environment. While there have been recent efforts to reduce the use of Hg cells, some of the emitted Hg can be transformed to neurotoxic methylmercury (MeHg). Here, we aimed (i) to study the dispersion of Hg in four reservoirs located downstream of a chlor-alkali plant along the Olt River (Romania) and (ii) to track the activity of bacterial functional genes involved in Hg methylation. Total Hg (THg) concentrations in water and sediments decreased successively from the initial reservoir to downstream reservoirs. Suspended fine size particles and seston appeared to be responsible for the transport of THg into downstream reservoirs, while macrophytes reflected the local bioavailability of Hg. The concentration and proportion of MeHg were correlated with THg, but were not correlated with bacterial activity in sediments, while the abundance of hgcA transcript correlated with organic matter and Cl(-) concentration, indicating the importance of Hg bioavailability in sediments for Hg methylation. Our data clearly highlights the importance of considering Hg contamination as a legacy pollutant since there is a high risk of continued Hg accumulation in food webs long after Hg-cell phase out.
Collapse
Affiliation(s)
- Andrea G Bravo
- Limnology/Department of Ecology and Genetics, Uppsala University, Norbyvägen 18D, 75236, Uppsala, Sweden
| | - Jean-Luc Loizeau
- Institute F.-A. Forel, Earth and Environmental Sciences, University of Geneva, 10, Route de Suisse, 1290, Versoix, Switzerland
| | - Perrine Dranguet
- Institute F.-A. Forel, Earth and Environmental Sciences, University of Geneva, 10, Route de Suisse, 1290, Versoix, Switzerland
| | - Stamatina Makri
- Institute F.-A. Forel, Earth and Environmental Sciences, University of Geneva, 10, Route de Suisse, 1290, Versoix, Switzerland
| | - Erik Björn
- Department of Chemistry, Umeå University, SE-90187, Umeå, Sweden
| | - Viorel Gh Ungureanu
- Faculty of Geology and Geophysics, University of Bucharest, Bucharest, Romania
- GeoEcoMar, National Research and Development Institute for Marine Geology and Geoecology, Bucharest, Romania
| | - Vera I Slaveykova
- Institute F.-A. Forel, Earth and Environmental Sciences, University of Geneva, 10, Route de Suisse, 1290, Versoix, Switzerland
| | - Claudia Cosio
- Institute F.-A. Forel, Earth and Environmental Sciences, University of Geneva, 10, Route de Suisse, 1290, Versoix, Switzerland.
| |
Collapse
|
15
|
Palanques A, Grimalt J, Belzunces M, Estrada F, Puig P, Guillén J. Massive accumulation of highly polluted sedimentary deposits by river damming. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 497-498:369-381. [PMID: 25146906 DOI: 10.1016/j.scitotenv.2014.07.091] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/22/2014] [Accepted: 07/23/2014] [Indexed: 05/12/2023]
Abstract
Uncontrolled dumping of anthropogenic waste in rivers regulated by dams has created contaminated deposits in reservoirs that have remained unidentified for decades. The Flix Reservoir is located in the Ebro River, the second largest river flowing into the NW Mediterranean, has been affected by residue dumping from a chlor-alkali electrochemical plant for decades. High-resolution seismic profiles, bathymetric data, surficial sediment samples and sediment cores were obtained in the Flix Reservoir to study the characteristics of the deposit accumulated by this dumping. These data were used to reconstruct the waste deposit history. Since the construction of the Flix Dam in 1948, more than 3.6×10(5) t of industrial waste has accumulated in the reservoir generating a delta-like deposit formed by three sediment lobes of fine-grained material highly contaminated by Hg, Cd, Zn and Cr (max: 640, 26, 420 and 750 mg kg(-1), respectively). This contamination was associated with the Hg that was used for the cathode in the electrochemical plant from 1949 and with the production of phosphorite derivatives from 1973. After the construction of two large dams only a few kilometres upstream during the 1960s, the solids discharged from the industrial complex became the main sediment source to the Flix Reservoir. The deposit has remained in the reservoir forming a delta that obstructs about 50% of the river water section. Its stability only depended on the flow retention by the Flix Dam. At present, this contaminated waste deposit is being removed from the water reservoir as it is a cause of concern for the environment and for human health downriver.
Collapse
Affiliation(s)
- Albert Palanques
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona 08003, Spain.
| | - Joan Grimalt
- Institute of Environmental Assessment and Water Research (CSIC), Jordi Girona, 18, Barcelona 08034, Spain
| | - Marc Belzunces
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona 08003, Spain
| | - Ferran Estrada
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona 08003, Spain
| | - Pere Puig
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona 08003, Spain
| | - Jorge Guillén
- Institute of Marine Sciences (CSIC), Passeig Maritim de la Barceloneta, 37-49, Barcelona 08003, Spain
| |
Collapse
|
16
|
Bravo AG, Cosio C, Amouroux D, Zopfi J, Chevalley PA, Spangenberg JE, Ungureanu VG, Dominik J. Extremely elevated methyl mercury levels in water, sediment and organisms in a Romanian reservoir affected by release of mercury from a chlor-alkali plant. WATER RESEARCH 2014; 49:391-405. [PMID: 24216231 DOI: 10.1016/j.watres.2013.10.024] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 09/17/2013] [Accepted: 10/09/2013] [Indexed: 05/25/2023]
Abstract
We examined mercury (Hg) biogeochemistry and biomagnification in the Babeni Reservoir, a system strongly affected by the release of Hg from a chlor-alkali plant. Total mercury (THg) concentrations in river water reached 88 ng L(-1) but decreased rapidly in the reservoir (to 9 ng L(-1)). In contrast, monomethylmercury (MMHg) concentrations increased from the upstream part of the reservoir to the central part (0.7 ng L(-1)), suggesting high methylation within the reservoir. Moreover, vertical water column profiles of THg and MMHg indicated that Hg methylation mainly occurred deep in the water column and at the sediment-water interface. The discharge of Hg from a chlor-alkali plant in Valcea region caused the highest MMHg concentrations ever found in non-piscivorous fish worldwide. MMHg concentrations and bioconcentration factors (BCF) of plankton and macrophytes revealed that the highest biomagnification of MMHg takes place in primary producers.
Collapse
Affiliation(s)
- Andrea Garcia Bravo
- Institute F.-A. Forel, University of Geneva, 10, Route de Suisse, 1290 Versoix, Switzerland.
| | - Claudia Cosio
- Institute F.-A. Forel, University of Geneva, 10, Route de Suisse, 1290 Versoix, Switzerland
| | - David Amouroux
- Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, IPREM UMR 5254 CNRS - Université de Pau et des Pays de l'Adour, Hélioparc, 64053 Pau, France
| | - Jakob Zopfi
- Environmental Geosciences, University of Basel, Bernoullistrasse 30, 4056 Basel, Switzerland
| | | | - Jorge E Spangenberg
- Institute of Earth Sciences, University of Lausanne, 1015 Lausanne, Switzerland
| | | | - Janusz Dominik
- Institute F.-A. Forel, University of Geneva, 10, Route de Suisse, 1290 Versoix, Switzerland
| |
Collapse
|
17
|
Regier N, Baerlocher L, Münsterkötter M, Farinelli L, Cosio C. Analysis of the Elodea nuttallii transcriptome in response to mercury and cadmium pollution: development of sensitive tools for rapid ecotoxicological testing. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:8825-8834. [PMID: 23802634 DOI: 10.1021/es401082h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Toxic metals polluting aquatic ecosystems are taken up by inhabitants and accumulate in the food web, affecting species at all trophic levels. It is therefore important to have good tools to assess the level of risk represented by toxic metals in the environment. Macrophytes are potential organisms for the identification of metal-responsive biomarkers but are still underrepresented in ecotoxicology. In the present study, we used next-generation sequencing to investigate the transcriptomic response of Elodea nuttallii exposed to enhanced concentrations of Hg and Cd. We de novo assembled more than 60 000 contigs, of which we found 170 to be regulated dose-dependently by Hg and 212 by Cd. Functional analysis showed that these genes were notably related to energy and metal homeostasis. Expression analysis using nCounter of a subset of genes showed that the gene expression pattern was able to assess toxic metal exposure in complex environmental samples and was more sensitive than other end points (e.g., bioaccumulation, photosynthesis, etc.). In conclusion, we demonstrate the feasibility of using gene expression signatures for the assessment of environmental contamination, using an organism without previous genetic information. This is of interest to ecotoxicology in a wider sense given the possibility to develop specific and sensitive bioassays.
Collapse
Affiliation(s)
- Nicole Regier
- Institut F.-A. Forel, University of Geneva , 10 route de Suisse, CP416, 1290 Versoix, Switzerland
| | | | | | | | | |
Collapse
|
18
|
Forensic Assessment of Metal Contaminated Rivers in the 21st Century Using Geochemical and Isotopic Tracers. MINERALS 2013. [DOI: 10.3390/min3020192] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
19
|
Li HB, Yu S, Li GL, Deng H, Xu B, Ding J, Gao JB, Hong YW, Wong MH. Spatial distribution and historical records of mercury sedimentation in urban lakes under urbanization impacts. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 445-446:117-125. [PMID: 23327992 DOI: 10.1016/j.scitotenv.2012.12.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 12/07/2012] [Accepted: 12/15/2012] [Indexed: 06/01/2023]
Abstract
China is assumed one of the largest contributors to the world's total mercury (Hg) emissions, with a rapid increase in anthropogenic Hg emissions. However, little is known about Hg fate and transport in urban areas of China. In this study, total Hg contents in surface (0-5 cm) sediments from lakes in 14 parks (3 in the central urban core (CUC) area, 5 in the developed urban (DDU) area, 2 in the developing urban (DIU) area, and 4 in the suburban (SU) area) and (210)Pb-dated sediment cores from lakes in 5 parks (3 in the CUC and 2 in the DDU) in Shanghai were assessed to compare current patterns (urbanization effect) with the historical records of Hg emissions over the past century. Total Hg content in surface sediments showed a clear urbanization pattern. Dated sediment cores revealed a 2-3 fold increase in total Hg content, while Hg fluxes exponentially increased from ~1900 to present and accelerated since 1990 when China's economy and urbanization booms started. Anthropogenic Hg fluxes in post-2000 ranged from 253 to 1452 μg m(-2) yr(-1), 2-7 times greater than preindustrial (pre-1900) Hg fluxes. Total Hg and Pb contents in both surface sediments and sediment cores were highly correlated and Hg flux in sediment cores also significantly correlated with annual coal consumption in the period 1949-2008. The significant correlations suggest that coal combustion is a major source of Hg emission in Shanghai.
Collapse
Affiliation(s)
- Hong-Bo Li
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Regier N, Larras F, Bravo AG, Ungureanu VG, Amouroux D, Cosio C. Mercury bioaccumulation in the aquatic plant Elodea nuttallii in the field and in microcosm: accumulation in shoots from the water might involve copper transporters. CHEMOSPHERE 2013; 90:595-602. [PMID: 23021383 DOI: 10.1016/j.chemosphere.2012.08.043] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 08/06/2012] [Accepted: 08/08/2012] [Indexed: 06/01/2023]
Abstract
Previous studies suggest that macrophytes might participate in bioaccumulation and biomagnification of toxic mercury (Hg) in aquatic environment. Hg bioaccumulation and uptake mechanisms in macrophytes need therefore to be studied. Amongst several macrophytes collected in an Hg contaminated reservoir in Romania, Elodea nuttallii showed a high organic and inorganic Hg accumulation and was then further studied in the laboratory. Tolerance and accumulation of Hg of this plant was also high in the microcosm. Basipetal transport of inorganic Hg was predominant, whereas acropetal transport of methyl-Hg was observed with apparently negligible methylation or demethylation in planta. Hg concentrations were higher in roots>leaves>stems and in top>middle>bottom of shoots. In shoots, more than 60% Hg was found intracellularly where it is believed to be highly available to predators. Accumulation in shoots was highly reduced by cold, death and by competition with Cu(+). Hg in E. nuttallii shoots seems to mainly originate from the water column, but methyl-Hg could also be remobilized from the sediments and might drive in part its entry in the food web. At the cellular level, uptake of Hg into the cell sap of shoots seems linked to the metabolism and to copper transporters. The present work highlights an important breakthrough in our understanding of Hg accumulation and biomagnifications: the remobilization of methyl-Hg from sediments to aquatic plants and differences in uptake mechanisms of inorganic and methyl-Hg in a macrophyte.
Collapse
Affiliation(s)
- Nicole Regier
- Institute F.-A. Forel, University of Geneva, 10 route de Suisse, CP 416, CH-1290 Versoix, Switzerland
| | | | | | | | | | | |
Collapse
|
21
|
Regier N, Frey B, Converse B, Roden E, Grosse-Honebrink A, Bravo AG, Cosio C. Effect of Elodea nuttallii roots on bacterial communities and MMHg proportion in a Hg polluted sediment. PLoS One 2012; 7:e45565. [PMID: 23029102 PMCID: PMC3444453 DOI: 10.1371/journal.pone.0045565] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 08/20/2012] [Indexed: 11/19/2022] Open
Abstract
The objective of this study was to assess the effect of a rooted macrophyte Elodea nuttallii on rhizosphere bacterial communities in Hg contaminated sediments. Specimens of E. nuttallii were exposed to sediments from the Hg contaminated Babeni reservoir (Olt River, Romania) in our microcosm. Plants were allowed to grow for two months until they occupied the entirety of the sediments. Total Hg and MMHg were analysed in sediments where an increased MMHg percentage of the total Hg in pore water of rhizosphere sediments was found. E. nuttallii roots also significantly changed the bacterial community structure in rhizosphere sediments compared to bulk sediments. Deltaproteobacteria dominated the rhizosphere bacterial community where members of Geobacteraceae within the Desulfuromonadales and Desulfobacteraceae were identified. Two bacterial operational taxonomic units (OTUs) which were phylogenetically related to sulfate-reducing bacteria (SRB) became abundant in the rhizosphere. We suggest that these phylotypes could be potentially methylating bacteria and might be responsible for the higher MMHg percentage of the total Hg in rhizosphere sediments. However, SRB were not significantly favoured in rhizosphere sediments as shown by qPCR. Our findings support the hypothesis that rooted macrophytes created a microenvironment favorable for Hg methylation. The presence of E. nuttallii in Hg contaminated sediments should therefore not be overlooked.
Collapse
Affiliation(s)
- Nicole Regier
- F.-A. Forel Institute, Geneva University, Versoix, Switzerland
| | - Beat Frey
- Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - Brandon Converse
- Department of Geoscience, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Eric Roden
- Department of Geoscience, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | | | | | - Claudia Cosio
- F.-A. Forel Institute, Geneva University, Versoix, Switzerland
- * E-mail:
| |
Collapse
|
22
|
Bravo AG, Loizeau JL, Bouchet S, Richard A, Rubin JF, Ungureanu VG, Amouroux D, Dominik J. Mercury human exposure through fish consumption in a reservoir contaminated by a chlor-alkali plant: Babeni reservoir (Romania). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2010; 17:1422-1432. [PMID: 20411344 DOI: 10.1007/s11356-010-0328-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Accepted: 03/18/2010] [Indexed: 05/29/2023]
Abstract
PURPOSE Chlor-alkali plants are one of the most important point sources of mercury to aquatic environment. The problem of Hg contamination has been studied in a region, Rm Valcea (Romania), impacted by the wastewater discharge of a chlor-alkali plant. The purpose of the present study is to evaluate the current status of mercury pollution in the Babeni reservoir (Olt River) and the exposure of local population via fish consumption to mercury originating from the chlor-alkali plant. METHODS Sediments were collected from Valcea, Govora and Babeni reservoirs. Grain size distribution, organic content and total mercury (THg) concentrations were analysed in sediments. Fish were purchased from local anglers, and the scalp hair was collected from volunteers. THg in sediment, fish and hair samples was determined using an atomic absorption spectrophotometer for Hg determination. Monomethylmercury (MMHg) was analysed in the muscle and liver tissues by species-specific isotope dilution and capillary gas chromatography hyphenated to inductively coupled plasma mass spectrometer. RESULTS High mercury concentrations were found in the sediments and in fish from Babeni reservoir, with a median of 2.1 mg/kg (IQR = 3.2) in sediments and a mean value of 1.8 +/- 0.8 mg/kg_ww in fish muscle. MMHg concentrations in fish were well above the WHO guidelines for fish consumption. Local population consuming fish from the Babeni reservoir had THg concentrations in hair significantly higher than those consuming fish from upstream reservoirs and/or from the shops and reached a median value of 2.5 mg/kg (IQR = 3.6). CONCLUSIONS The remnant pollution in the fish of this reservoir, and probably many other lakes and reservoirs receiving Hg polluted wastewater, represents a considerable health risk for the local fish consumers.
Collapse
|
23
|
Dufault R, Schnoll R, Lukiw WJ, LeBlanc B, Cornett C, Patrick L, Wallinga D, Gilbert SG, Crider R. Mercury exposure, nutritional deficiencies and metabolic disruptions may affect learning in children. BEHAVIORAL AND BRAIN FUNCTIONS : BBF 2009; 5:44. [PMID: 19860886 PMCID: PMC2773803 DOI: 10.1186/1744-9081-5-44] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2009] [Accepted: 10/27/2009] [Indexed: 12/27/2022]
Abstract
Among dietary factors, learning and behavior are influenced not only by nutrients, but also by exposure to toxic food contaminants such as mercury that can disrupt metabolic processes and alter neuronal plasticity. Neurons lacking in plasticity are a factor in neurodevelopmental disorders such as autism and mental retardation. Essential nutrients help maintain normal neuronal plasticity. Nutritional deficiencies, including deficiencies in the long chain polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid, the amino acid methionine, and the trace minerals zinc and selenium, have been shown to influence neuronal function and produce defects in neuronal plasticity, as well as impact behavior in children with attention deficit hyperactivity disorder. Nutritional deficiencies and mercury exposure have been shown to alter neuronal function and increase oxidative stress among children with autism. These dietary factors may be directly related to the development of behavior disorders and learning disabilities. Mercury, either individually or in concert with other factors, may be harmful if ingested in above average amounts or by sensitive individuals. High fructose corn syrup has been shown to contain trace amounts of mercury as a result of some manufacturing processes, and its consumption can also lead to zinc loss. Consumption of certain artificial food color additives has also been shown to lead to zinc deficiency. Dietary zinc is essential for maintaining the metabolic processes required for mercury elimination. Since high fructose corn syrup and artificial food color additives are common ingredients in many foodstuffs, their consumption should be considered in those individuals with nutritional deficits such as zinc deficiency or who are allergic or sensitive to the effects of mercury or unable to effectively metabolize and eliminate it from the body.
Collapse
Affiliation(s)
| | - Roseanne Schnoll
- Department of Health and Nutrition Sciences, Brooklyn College of CUNY, Brooklyn, NY, USA
| | - Walter J Lukiw
- Departments of Neuroscience and Ophthalmology, LSU Neuroscience Center. Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | | | - Charles Cornett
- Department of Chemistry and Engineering Physics, University of Wisconsin-Platteville, Platteville, WI, USA
| | - Lyn Patrick
- Contributing Editor, Alternative Medicine Review, Durango, CO, USA
| | - David Wallinga
- Institute for Agriculture and Trade Policy, Minneapolis, MN, USA
| | - Steven G Gilbert
- Institute of Neurotoxicology and Neurological Disorders, 8232 14th Avenue NE, Seattle, WA, USA
| | | |
Collapse
|
24
|
Giger W, Bloesch J, Zobrist J. ESTROM 2008 International Conference. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2009; 16 Suppl 1:S9-S13. [PMID: 19543760 DOI: 10.1007/s11356-009-0206-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Accepted: 05/28/2009] [Indexed: 05/27/2023]
Affiliation(s)
- Walter Giger
- GRC-Giger Research Consulting, Zurich, Switzerland.
| | | | | |
Collapse
|
25
|
Giger W, Panin N. ESTROM, Environmental Science and Technology in Romania-programme overview. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2009; 16 Suppl 1:S3-S8. [PMID: 19533194 DOI: 10.1007/s11356-009-0202-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Accepted: 05/28/2009] [Indexed: 05/27/2023]
Affiliation(s)
- Walter Giger
- GRC, Giger Research Consulting, Zurich, Switzerland.
| | | |
Collapse
|