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Giarratano E, Trovant B, Hernández-Moresino RD. Asian clam Corbicula fluminea as potential biomonitor of microplastics and metal(oid)s in a Patagonian River. MARINE ENVIRONMENTAL RESEARCH 2024; 198:106548. [PMID: 38733740 DOI: 10.1016/j.marenvres.2024.106548] [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: 02/08/2024] [Revised: 04/08/2024] [Accepted: 05/06/2024] [Indexed: 05/13/2024]
Abstract
This study summarizes the concentration in dry weight (dw) of several metal(oid)s (As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn), as well as the abundance and characteristics of microplastics (MP) in wet weight (ww) of the soft tissues of clam Corbicula fluminea from Chubut River (Patagonia, Argentina). The contents of essential elements were in the following decreasing order: Zn > Mn > Cu > Ni; meanwhile, non-essential elements Cd, Cr and Pb were below the detection limit (<0.5 μg/g dw). A high mean concentration of As (6.1 ± 0.3 μg/g dw) was found, surpassing the maximum allowable limit established by the Argentine Food Code for bivalve molluscs. The number of MP ranged from 0.07 to 1.27 items/ind. and from 0.2 to 2.9 items/g ww. Fibers were the most common shape, mainly transparent. The size of MP ranged from 42 to 1917 μm, accounting for 62 % of MP between 50 and 450 μm. The dominant polymer was PET based on the results of Raman spectroscopy. Based on the widespread distribution of MP in the environment and the wide range of effects on organisms, it is necessary to develop long-term monitoring programs for MP contamination in different environmental matrices. Understanding the bioaccumulation of MP in bivalves is crucial to assess the potential risk to human health through consumption and to the ecosystem. We propose that the widespread Asian clam could serve as a useful biomonitor for MP and As pollution in freshwater and estuarine environments such as the Chubut River.
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Affiliation(s)
- Erica Giarratano
- Centro para el estudio de Sistemas Marinos (CESIMAR - CONICET), Boulevard Brown 2915, U9120ACP Puerto Madryn, Chubut, Argentina.
| | - Berenice Trovant
- Instituto de Diversidad y Evolución Austral (IDEAus - CONICET), Boulevard Brown 2915, U9120ACP Puerto Madryn, Chubut, Argentina.
| | - Rodrigo D Hernández-Moresino
- Centro para el estudio de Sistemas Marinos (CESIMAR - CONICET), Boulevard Brown 2915, U9120ACP Puerto Madryn, Chubut, Argentina.
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Sturla Lompré J, Malanga G, Gil MN, Giarratano E. Biochemical response and tissue-specific accumulation of scallop Aequipecten tehuelchus from Patagonia, Argentina after exposure to inorganic arsenic. CHEMOSPHERE 2024; 349:140946. [PMID: 38103654 DOI: 10.1016/j.chemosphere.2023.140946] [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: 06/26/2023] [Revised: 11/14/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
This study investigates the effects of different inorganic arsenic (As III) concentrations (0, 125, 500 and 1000 μg As/L) following two exposure times (7 and 14 days) on gills, digestive gland and muscle of scallop Aequipecten tehuelchus from Patagonia, Argentina. A biochemical approach was used to investigate oxidative stress-related parameters after different As concentrations and exposure times. Although the accumulation of As was of the same order of magnitude in all tissues, the results showed distinct tissue-specific oxidative responses to this metalloid. Furthermore, the variation in exposure time had no significant effect on As accumulation in any of the three tissues. In gills, despite no reactive oxygen and nitrogen species (RONS) were detected, there was an increase in catalase (CAT) activity and metallothionein (MT) levels. Conversely, digestive gland showed RONS production without a rise in CAT and glutathione S-transferases (GST) activities, but with an increase in MT levels. In muscle, RONS production and CAT activity kept constant or decreased, while MT levels remained unchanged. In addition, exposure time demonstrated its critical role in gills by influencing the response of CAT, GST and MT, particularly at high As concentrations, while exposure time did not affect the biochemical stress parameters in the digestive gland and muscle. Interestingly, neither concentration of As produced lipid damage, showing the effectiveness of the antioxidant mechanisms to avoid it. These results emphasize that A. tehuelchus exhibited no time-dependent effects in response to As exposure, while showing tissue-specific responses characterized by significant concentration-dependent effects of As. This study provides a comprehensive insight by considering the combined effects of time and concentration of a contaminant and distinguishing its effects on specific tissues, a dimension often overlooked in the existing literature. Subsequent studies should prioritize the analysis of additional contaminants in species with increased sensitivity.
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Affiliation(s)
- Julieta Sturla Lompré
- Laboratorio de Química Ambiental y Ecotoxicología, Centro para el Estudio de Sistemas Marinos (CESIMAR-CONICET), Bv. Almte Brown 2915, Puerto Madryn, U9120, Chubut, Argentina; Universidad Nacional de la Patagonia San Juan Bosco (UNPSJB), Bv. Almte Brown 3051, Puerto Madryn, U9120, Chubut, Argentina.
| | - Gabriela Malanga
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Fisicoquímica. Junín 954, Ciudad Autónoma de Buenos Aires C1113 AAD, Buenos Aires, Argentina; Instituto de Bioquímica y Medicina Molecular Dr. A. Boveris (IBIMOL), CONICET-Universidad de Buenos Aires, Junín 954, Ciudad Autónoma de Buenos Aires C1113 AAD, Buenos Aires, Argentina.
| | - Mónica Noemí Gil
- Laboratorio de Química Ambiental y Ecotoxicología, Centro para el Estudio de Sistemas Marinos (CESIMAR-CONICET), Bv. Almte Brown 2915, Puerto Madryn, U9120, Chubut, Argentina; Universidad Nacional de la Patagonia San Juan Bosco (UNPSJB), Bv. Almte Brown 3051, Puerto Madryn, U9120, Chubut, Argentina.
| | - Erica Giarratano
- Laboratorio de Química Ambiental y Ecotoxicología, Centro para el Estudio de Sistemas Marinos (CESIMAR-CONICET), Bv. Almte Brown 2915, Puerto Madryn, U9120, Chubut, Argentina.
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Kirilovsky ER, Anguiano OL, Bongiovanni GA, Ferrari A. Effects of acute arsenic exposure in two different populations of Hyalella curvispina amphipods from North Patagonia Argentina. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2022; 85:71-88. [PMID: 34496719 DOI: 10.1080/15287394.2021.1975589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Arsenic (As) is a toxic metalloid present in high levels in diverse regions of Argentina. The aim of this study was to determine acute As-mediated toxicity in two different populations of autochthonous Hyalella curvispina amphipods from a reference site (LB) and an agricultural one (FO) within North Patagonia Argentina. Previously, both populations exhibited significant differences in pesticide susceptibility. Lab assays were performed to determine acute lethal concentrations, as well as some biochemical parameters. Lethal concentration (LC50) values obtained after 48 and 96 hr As exposure were not significantly different between these populations, although FO amphipods appeared slightly less susceptible. LC50-48 hr values were 3.33 and 3.92 mg/L As, while LC50-96 hr values were 1.76 and 2.14 mg/L As for LB and FO amphipods. The no observed effect concentration (NOEC) values were 0.5 mg/L As. Cholinesterase (ChE) activity was significantly diminished by As acute exposure (0.5-1.5 mg/L As), indicative of a significant neurotoxic action for this metalloid in both amphipod populations. Activities of catalase (CAT) and glutathione S-transferase (GST) and levels of reduced glutathione (GSH) were differentially altered following As exposure. CAT activity was increased after 96 hr As exposure. GST activity and GSH levels were significantly elevated followed by either a decrease or a return to control values after 96 hr treatment. However, additional studies are necessary to understand the mechanisms underlying the As-mediated oxidative effects in H. curvispina. Our findings suggest that measurement of ChE activity in H. curvispina amphipods might serve as a useful biomarker of As exposure and effect.
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Affiliation(s)
- Eva R Kirilovsky
- Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas, PROBIEN, (CONICET- UNCo), Neuquén, Argentina
- Facultad De Ciencias Médicas, Universidad Nacional Del Comahue (UNCo), Río Negro, Argentina
| | - Olga L Anguiano
- Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas, PROBIEN, (CONICET- UNCo), Neuquén, Argentina
- Facultad De Ingeniería, Universidad Nacional Del Comahue (UNCo), Neuquén, Argentina
| | - Guillermina A Bongiovanni
- Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas, PROBIEN, (CONICET- UNCo), Neuquén, Argentina
- Facultad De Ciencias Agrarias, Universidad Nacional Del Comahue (UNCo), Neuquén, Argentina
| | - Ana Ferrari
- Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas, PROBIEN, (CONICET- UNCo), Neuquén, Argentina
- Facultad De Ciencias Médicas, Universidad Nacional Del Comahue (UNCo), Río Negro, Argentina
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Bundschuh J, Schneider J, Alam MA, Niazi NK, Herath I, Parvez F, Tomaszewska B, Guilherme LRG, Maity JP, López DL, Cirelli AF, Pérez-Carrera A, Morales-Simfors N, Alarcón-Herrera MT, Baisch P, Mohan D, Mukherjee A. Seven potential sources of arsenic pollution in Latin America and their environmental and health impacts. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 780:146274. [PMID: 34030289 DOI: 10.1016/j.scitotenv.2021.146274] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/25/2021] [Accepted: 02/28/2021] [Indexed: 06/12/2023]
Abstract
This review presents a holistic overview of the occurrence, mobilization, and pathways of arsenic (As) from predominantly geogenic sources into different near-surface environmental compartments, together with the respective reported or potential impacts on human health in Latin America. The main sources and pathways of As pollution in this region include: (i) volcanism and geothermalism: (a) volcanic rocks, fluids (e.g., gases) and ash, including large-scale transport of the latter through different mechanisms, (b) geothermal fluids and their exploitation; (ii) natural lixiviation and accelerated mobilization from (mostly sulfidic) metal ore deposits by mining and related activities; (iii) coal deposits and their exploitation; (iv) hydrocarbon reservoirs and co-produced water during exploitation; (v) solute and sediment transport through rivers to the sea; (vi) atmospheric As (dust and aerosol); and (vii) As exposure through geophagy and involuntary ingestion. The two most important and well-recognized sources and mechanisms for As release into the Latin American population's environments are: (i) volcanism and geothermalism, and (ii) strongly accelerated As release from geogenic sources by mining and related activities. Several new analyses from As-endemic areas of Latin America emphasize that As-related mortality and morbidity continue to rise even after decadal efforts towards lowering As exposure. Several public health regulatory institutions have classified As and its compounds as carcinogenic chemicals, as As uptake can affect several organ systems, viz. dermal, gastrointestinal, peptic, neurological, respiratory, reproductive, following exposure. Accordingly, ingesting large amounts of As can damage the stomach, kidneys, liver, heart, and nervous system; and, in severe cases, may cause death. Moreover, breathing air with high As levels can cause lung damage, shortness of breath, chest pain, and cough. Further, As compounds, being corrosive, can also cause skin lesions or damage eyes, and long-term exposure to As can lead to cancer development in several organs.
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Affiliation(s)
- Jochen Bundschuh
- UNESCO Chair on Groundwater Arsenic within the 2030 Agenda for Sustainable Development, University of Southern Queensland, West Street, Toowoomba 4350, Queensland, Australia.
| | - Jerusa Schneider
- Department of Geology and Natural Resources, Institute of Geosciences, University of Campinas, 13083-855 Campinas, SP, Brazil; Faculty of Agricultural Sciences, Federal University of Grande Dourados, João Rosa Góes St., 1761, Dourados, Mato Grosso do Sul, 79804-970, Brazil
| | - Mohammad Ayaz Alam
- Departamento de Geología, Facultad de Ingeniería, Universidad de Atacama, Avenida Copayapu 485, Copiapó, Región de Atacama, Chile
| | - Nabeel Khan Niazi
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan
| | - Indika Herath
- UNESCO Chair on Groundwater Arsenic within the 2030 Agenda for Sustainable Development, University of Southern Queensland, West Street, Toowoomba 4350, Queensland, Australia
| | - Faruque Parvez
- Department of Environmental Health Sciences, Columbia University, 60 Haven Ave, B-1, New York, NY 10032, USA
| | - Barbara Tomaszewska
- AGH University of Science and Technology, Mickiewicza 30 Av., 30-059 Kraków, Poland
| | | | - Jyoti Prakash Maity
- Department of Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Min-Hsiung, Chiayi County 62102, Taiwan
| | - Dina L López
- Department of Geological Sciences, Ohio University, 316 Clippinger Laboratories, Athens, OH, USA
| | - Alicia Fernández Cirelli
- University of Buenos Aires, Faculty of Veterinary Sciences, Instituto de Investigaciones en Producción Animal (UBA-CONICET), Centro de Estudios, Transdiciplinarios del Agua (UBA), Av. Chorroarín 280, CABA C1427CWO, Argentina
| | - Alejo Pérez-Carrera
- University of Buenos Aires, Faculty of Veterinary Sciences, Centro de Estudios Transdiciplinarios del Agua (UBA), Instituto de Investigaciones en Producción Animal (UBA-CONICET), Cátedra de Química Orgánica de Biomoléculas, Av. Chorroarín 280, CABA C1427CWO, Argentina
| | - Nury Morales-Simfors
- UNESCO Chair on Groundwater Arsenic within the 2030 Agenda for Sustainable Development, University of Southern Queensland, West Street, Toowoomba 4350, Queensland, Australia; RISE Research Institutes of Sweden, Division ICT-RISE SICS East, Linköping SE-581.83, Sweden
| | - Maria Teresa Alarcón-Herrera
- Departamento de Ingeniería Sustentable, Centro de Investigación en Materiales Avanzados SC Unidad Durango, C. CIMAV # 110, Ejido Arroyo Seco, Durango, Dgo., Mexico
| | - Paulo Baisch
- Laboratório de Oceanografia Geológica, Instituto de Oceanografia, Universidade Federal do Rio Grande (FURG), Campus Carreiros, CP 474, CEP 96203-900 Rio Grande, RS, Brazil
| | - Dinesh Mohan
- UNESCO Chair on Groundwater Arsenic within the 2030 Agenda for Sustainable Development, University of Southern Queensland, West Street, Toowoomba 4350, Queensland, Australia; School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Abhijit Mukherjee
- Department of Geology and Geophysics, Indian Institute of Technology (IIT), Kharagpur, West Bengal 721302, India
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Conti ME, Plà R, Simone C, Jasan R, Finoia MG. Implementing the monitoring breakdown structure: native lichens as biomonitors of element deposition in the southern Patagonian forest connected with the Puyehue volcano event in 2011-a 6-year survey (2006-2012). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:38819-38834. [PMID: 32632679 DOI: 10.1007/s11356-020-10001-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/02/2020] [Indexed: 05/02/2023]
Abstract
This study aims to investigate the airborne elements' deposition by using native Usnea barbata lichens as biomonitors in the forested areas of Tierra del Fuego (TdF, southern Patagonia), an apparently pristine environment. The present study is linked to the volcanic eruption of the Puyehue-Cordón Caulle which started in north Patagonia in June 2011, which gives rise to long-distance transport of pollutants through the atmosphere at 1700 km from our sampling sites. The monitoring breakdown structure (MBS) was applied to three sampling campaigns in 2006 (baseline) ➔ 2011-2012 (3 and 15 months after the volcanic event, respectively). We have on purpose enhanced the information variety endowment: (i) Seventy-one referenced sites were double sampled; (ii) up to 426 composite lichen samples were collected; (iii) twenty-six elements were measured by neutron activation analysis (As, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, U, Yb, Zn) for samples of 2011 and 2012 campaigns; (iv) thirteen common elements (As, Ba, Ca, Co, Cr, Cs, Fe, K, Na, Sb, Se, U, Zn) were determined in 2006 for the baseline comparison. The natural contamination by tephras is reflected by lichens more clearly in the 2011 campaign, where Ba, Cr, Na, Ca, Cs, and U showed higher median levels compared with the baseline campaign (2006). Ca, K, and Na were the most accumulated elements after the volcano event and could be associated with the volcanic ashes' deposition. Rare earth elements (REEs) showed no significant bioaccumulation levels between 2011 and 2012, indicating their association with higher lithogenic inputs than volcanic ashes. Using the Earth's crust as reference, nine elements (As, Ba, Br, Ca, K, Na, Sb, Se, and Zn) presented moderate/significant mean enrichment factor (EF) values (> 5). The usefulness of Usnea barbata as test species for direct biomonitoring oriented kinetic studies in areas characterized by a low human impact is confirmed. Eventually, our results confirm that TdF is not an actual pristine environment as earlier supposed.
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Affiliation(s)
- Marcelo Enrique Conti
- Department of Management, University of Rome, Sapienza, Via del Castro Laurenziano 9, 00161, Rome, Italy.
| | - Rita Plà
- Departamento Química Nuclear, GAATEN, Comisión Nacional de Energía Atómica (CNEA), Av. del Libertador 8250, 1429, Buenos Aires, Argentina
| | - Cristina Simone
- Department of Management, University of Rome, Sapienza, Via del Castro Laurenziano 9, 00161, Rome, Italy
| | - Raquel Jasan
- Departamento Química Nuclear, GAATEN, Comisión Nacional de Energía Atómica (CNEA), Av. del Libertador 8250, 1429, Buenos Aires, Argentina
| | - Maria Grazia Finoia
- Institute for Environmental Protection and Research (ISPRA), Via di Casalotti 300, 00166, Rome, Italy
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Germán A, Andreo V, Tauro C, Scavuzzo CM, Ferral A. A novel method based on time series satellite data analysis to detect algal blooms. ECOL INFORM 2020. [DOI: 10.1016/j.ecoinf.2020.101131] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Villalba E, Tanjal C, Borzi G, Páez G, Carol E. Geogenic arsenic contamination of wet-meadows associated with a geothermal system in an arid region and its relevance for drinking water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137571. [PMID: 32135286 DOI: 10.1016/j.scitotenv.2020.137571] [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: 01/08/2020] [Revised: 02/21/2020] [Accepted: 02/24/2020] [Indexed: 06/10/2023]
Abstract
Arsenic (As) is an important component in thermal springs, which can reach water sources constituting an important hazard for both the environment and people. For this reason, the aim of this paper is to analyze the geologic and geochemical processes that determine the presence and concentration of As in wet-meadows associated to a geothermal field in Patagonia (Argentina) which is used as water supply. To achieve this, during field surveys temperature, pH and electrical conductivity were measured and water and rock samples were taken. Major ions and stable isotopes were determined in water samples while As content was analyzed in both water and rock samples. Due to geological control and chemical analyses, three areas were recognized with respect to major streams in the geothermal field: wet-meadows at headwaters, thermal springs at mid basin and wet-meadows at down basin. Even though, water in wet-meadows have the same origin the obtained results evidence how thermal springs at mid-basin influence the chemistry of these wetlands, particularly those at down basin. In the latter, As raises over two orders of magnitude than the ones at headwaters which surpasses the reference limit, proving that thermal springs are also responsible for the increase of the As content in water changing its quality as a source of potable water. The concentration of this metalloid could be higher but it is retained in travertine and sinter deposits formed near the geothermal discharge area. Understanding processes controlling water quality and the chemistry of As in this type of wetlands is of vital importance, mainly in an arid region where water supply sources are scarce.
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Affiliation(s)
- Esteban Villalba
- Centro de Investigaciones Geológicas, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CIG-UNLP-CONICET), Diagonal 113 #275, La Plata, Argentina.
| | - Carolina Tanjal
- Centro de Investigaciones Geológicas, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CIG-UNLP-CONICET), Diagonal 113 #275, La Plata, Argentina
| | - Guido Borzi
- Centro de Investigaciones Geológicas, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CIG-UNLP-CONICET), Diagonal 113 #275, La Plata, Argentina
| | - Gerardo Páez
- Instituto de Recursos Minerales, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (INREMI-UNLP-CONICET), Belize
| | - Eleonora Carol
- Centro de Investigaciones Geológicas, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (CIG-UNLP-CONICET), Diagonal 113 #275, La Plata, Argentina.
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Zhang J, Zhou F, Liu Y, Huang F, Zhang C. Effect of extracellular polymeric substances on arsenic accumulation in Chlorella pyrenoidosa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 704:135368. [PMID: 31831249 DOI: 10.1016/j.scitotenv.2019.135368] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/01/2019] [Accepted: 11/01/2019] [Indexed: 05/27/2023]
Abstract
Inorganic arsenic (iAs) in its dominant dissolved phase in the environment is known to pose major threats to ecological and human health. While the biological effects in many arsenic-bearing freshwaters have been extensively studied, the behavior and bioaccumulation of dissolved iAS in the presence of extracellular polymeric substances (EPS) still remains to be a critical knowledge gap. In this study, the uptakes and kinetic characteristics of iAs were studied using Chlorella pyrenoidosa (a typical freshwater green algae) by addressing the different effects of EPS on arsenite (AsШ) and arsenate (AsV). The arsenic uptake capacity increased as the exposure concentration increased from 0 to 300 µmol L-1, and the uptake rate constants (Ku) in the Bio-dynamic model were greater for AsV than AsШ (0.63-11.57 L g-1 h-1 vs. 0.44-5.43 L g-1 h-1). The toxic effects as mitigated by EPS were observed through the morphological changes of algal cells by TEM and SEM. When compared with the EPS-free algal cells (EPS-F), EPS-covered cells (EPS-C) had a higher arsenic adsorption capacity through EPS-enhanced surface adsorption and reduced intracellular uptake. The overall decrease (35% and 23.3% for AsШ and AsV, respectively) in the maximum uptake capacity in intact algae cells favors cell's tolerance to the toxic effects of iAs. These observed discrepancies between AsШ and AsV and between EPS-C and EPS-F were further elucidated through morphological images (TEM and SEM) and molecular/atomic spectroscopic data that combine three-dimensional excitation-emission matrix fluorescence spectroscopy (3D-EEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Altogether, the spectroscopic evidence revealed the interactions of iAs with C-O-C, C-O-H and -NH2 functional groups in EPS' tyrosine- and tryptophan-like proteins as the binding sites. Overall, this study for the first time provides comprehensive evidence on the iAs-EPS interactions. Such insights will benefit our understanding of the biogeochemical processes of iAs and the strategic development of bioremediation techniques involving microalgae in the natural and engineered systems.
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Affiliation(s)
- Jianying Zhang
- College of Environmental and Resource Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang Province 310058, China; National Demonstration Center for Experimental Environment and Resources Education (Zhejiang University), Hangzhou 310058, China.
| | - Fang Zhou
- College of Environmental and Resource Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang Province 310058, China
| | - Yaoxuan Liu
- College of Environmental and Resource Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang Province 310058, China
| | - Fei Huang
- College of Environmental and Resource Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang Province 310058, China
| | - Chunlong Zhang
- Department of Environmental Science, University of Houston-Clear Lake, Houston, TX 77058, United States
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