Pub Date : 2022-06-01DOI: 10.3389/fenvc.2022.905170
J. Uwayezu, L. Yeung, M. Bäckström
Perfluorooctane sulfonic acid (PFOS) has been produced in large quantities for the use in various applications. As a consequence, PFOS is ubiquitous in the environment. Managing transportation of PFOS requires a clear understanding of PFOS mobilization in soils and their interactions with different soil components. The current study investigated a pH-dependent sorption of PFOS isomers onto soil and the effect of dissolved humic substances and Na2SO4. Sorption experiments of PFOS isomers was conducted on top and subsoils to assess their capacity to retain PFOS. Topsoil and subsoil samples were sampled from two areas in Kvarntorp, Kumla, Sweden. Sorption experiments were performed by shaking a mixture of soil and soil solutions spiked with PFOS isomers. One way ANOVA showed that linear PFOS (L-PFOS) and branched PFOS (Br-PFOS) isomers showed different sorption behavior onto soils. Calculated logarithmic partition coefficients revealed that L-PFOS is readily sorbed onto soils sampled at area 1) at very low pH (<4.5) whereas it was the least sorbed onto soils collected at area 2) under the studied pH range. Electrostatic interactions governed the sorption of PFOS isomers during acidic conditions whereas other mechanism controlled the sorption during neutral to alkaline conditions. The presence of humic acid enhanced the sorption of all PFOS isomers whereas fulvic acid inhibited their sorption onto soil. Sorption results revealed that the topsoil had a high capacity to sorb all PFOS isomers compared to the subsoil from the same area. For soils collected from an area covered by young oak trees, a high sorption on the topsoil was attributed to a high organic content [measured as loss on ignition (LOI)] and cation exchange capacity (CEC). However, there was no correlation between sorption capacity and LOI or CEC content for soil collected from another area covered by spruce forest. This suggested that the sorption on latter soils was controlled by other physicochemical properties.
{"title":"Sorption of Perfluorooctane Sulfonic Acid Including Its Isomers to Soils: Effects of pH, Natural Organic Matter and Na2SO4","authors":"J. Uwayezu, L. Yeung, M. Bäckström","doi":"10.3389/fenvc.2022.905170","DOIUrl":"https://doi.org/10.3389/fenvc.2022.905170","url":null,"abstract":"Perfluorooctane sulfonic acid (PFOS) has been produced in large quantities for the use in various applications. As a consequence, PFOS is ubiquitous in the environment. Managing transportation of PFOS requires a clear understanding of PFOS mobilization in soils and their interactions with different soil components. The current study investigated a pH-dependent sorption of PFOS isomers onto soil and the effect of dissolved humic substances and Na2SO4. Sorption experiments of PFOS isomers was conducted on top and subsoils to assess their capacity to retain PFOS. Topsoil and subsoil samples were sampled from two areas in Kvarntorp, Kumla, Sweden. Sorption experiments were performed by shaking a mixture of soil and soil solutions spiked with PFOS isomers. One way ANOVA showed that linear PFOS (L-PFOS) and branched PFOS (Br-PFOS) isomers showed different sorption behavior onto soils. Calculated logarithmic partition coefficients revealed that L-PFOS is readily sorbed onto soils sampled at area 1) at very low pH (<4.5) whereas it was the least sorbed onto soils collected at area 2) under the studied pH range. Electrostatic interactions governed the sorption of PFOS isomers during acidic conditions whereas other mechanism controlled the sorption during neutral to alkaline conditions. The presence of humic acid enhanced the sorption of all PFOS isomers whereas fulvic acid inhibited their sorption onto soil. Sorption results revealed that the topsoil had a high capacity to sorb all PFOS isomers compared to the subsoil from the same area. For soils collected from an area covered by young oak trees, a high sorption on the topsoil was attributed to a high organic content [measured as loss on ignition (LOI)] and cation exchange capacity (CEC). However, there was no correlation between sorption capacity and LOI or CEC content for soil collected from another area covered by spruce forest. This suggested that the sorption on latter soils was controlled by other physicochemical properties.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41606411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-20DOI: 10.3389/fenvc.2022.847682
Kamal K. Maharjan, Philip B. Jørgensen, M. Rezaei, M. Johnson
Carbon dioxide is a waste product of human metabolism that is unwanted in the indoor atmosphere. Here we test advanced materials that could be used to pump away carbon dioxide and thereby improve indoor air quality. Metal-organic framework (MOF) structures have a variety of properties that make them attractive for direct air capture (DAC) of CO2. In this study, Mg2 (dobpdc4- = 4,4-dioxidobiphenyl-3,3-dicarboxylate) and m-2-m-Mg2(dobpdc) were evaluated for their ability to adsorb and desorb CO2 at ambient atmospheric conditions via a thermal swing. The Mg2(dobpdc) sample did not show appreciable interaction with CO2 in contrast to the diamine-appended version. The molar occupancy of CO2 on the active sites of m-2-m-Mg2 (dobpdc) (m-2-m = N,N-dimethylethylenediamine) during adsorption and desorption was in the range of 5.6–11.8%. These experiments showed the rapid ad- and de-sorption of CO2 by the MOF. Relative humidity was seen to be an important variable and the performance of the tested structures decreased slightly after several cycles of use.
{"title":"Diamine-Appended Metal Oxide Framework Materials for Thermal-Swing Ad- and Desorption of Carbon Dioxide at Ambient Conditions","authors":"Kamal K. Maharjan, Philip B. Jørgensen, M. Rezaei, M. Johnson","doi":"10.3389/fenvc.2022.847682","DOIUrl":"https://doi.org/10.3389/fenvc.2022.847682","url":null,"abstract":"Carbon dioxide is a waste product of human metabolism that is unwanted in the indoor atmosphere. Here we test advanced materials that could be used to pump away carbon dioxide and thereby improve indoor air quality. Metal-organic framework (MOF) structures have a variety of properties that make them attractive for direct air capture (DAC) of CO2. In this study, Mg2 (dobpdc4- = 4,4-dioxidobiphenyl-3,3-dicarboxylate) and m-2-m-Mg2(dobpdc) were evaluated for their ability to adsorb and desorb CO2 at ambient atmospheric conditions via a thermal swing. The Mg2(dobpdc) sample did not show appreciable interaction with CO2 in contrast to the diamine-appended version. The molar occupancy of CO2 on the active sites of m-2-m-Mg2 (dobpdc) (m-2-m = N,N-dimethylethylenediamine) during adsorption and desorption was in the range of 5.6–11.8%. These experiments showed the rapid ad- and de-sorption of CO2 by the MOF. Relative humidity was seen to be an important variable and the performance of the tested structures decreased slightly after several cycles of use.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49658498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-11DOI: 10.3389/fenvc.2022.905303
J. Thery, Capucine Bialais, Maria Kazour, M. Moreau, Dylan Dufour, S. Benali, R. Amara, S. Monchy, J. Raquez, S. Souissi
This study investigates several methods to identify microplastics (MPs) of small size ranges (<10 µm) in the copepod Eurytemora affinis collected in the Seine estuary (France) and identified using epifluorescence microscopy and Raman microspectroscopy. In order to calibrate the methodology, copepods obtained from cultures were used. Firstly, we labelled three types of MPs (i.e., Polystyrene, Polyethylene, and Polylactic acid) with Nile Red and confirmed their ingestion by E. affinis with epifluorescence microscopy. Considering the convenient detection of Nile Red labelled MPs using epifluorescence observation, we tried to pair this method with Raman microspectroscopy. For this, we developed an enzymatic digestion method consisting of copepods digestion using Proteinase K followed by sonication in order to fragment their cuticle. The lysate was then vacuum filtered on black polycarbonate membrane filters that were the most appropriate for epifluorescence microscopy. Potential MPs were dyed with Nile Red directly on the filter, which allowed a relatively rapid visual detection. However, results showed that black polycarbonate membrane filters induced a significant background fluorescence during Raman identification of MPs and hence particles smaller than 10 µm could not be characterized. In this case, we were not able to link staining method with micro-Raman for the size range of MPs targeted in this study. Thus, aluminum oxide filters were tested, and staining method was replaced by a classical observation with stereomicroscopic magnifier to delimit areas of observation for Raman microscopic identification. Aluminum oxide filters induced less fluorescence, allowing the detection of MPs (as small as 1 µm diameter) on copepods from laboratory cultures exposed with MPs. We applied this method on copepods collected in the natural environment. Within a pool of 20 copepods of three replicates, we identified 17 MPs (average of 0.28 MPs/copepod) composed of eight different polymer types and six colors. These MPs corresponded to 59% of fibres with 14.1 ± 9.4 µm diameter and 391.6 ± 600.4 µm length along with 41% of fragments with an average diameter of 13.2 µm ± 9.5 µm. This study reports a novel approach to detect the presence of small particles of MPs ingested by copepods in the natural environment.
{"title":"A New Method for Microplastics Identification in Copepods","authors":"J. Thery, Capucine Bialais, Maria Kazour, M. Moreau, Dylan Dufour, S. Benali, R. Amara, S. Monchy, J. Raquez, S. Souissi","doi":"10.3389/fenvc.2022.905303","DOIUrl":"https://doi.org/10.3389/fenvc.2022.905303","url":null,"abstract":"This study investigates several methods to identify microplastics (MPs) of small size ranges (<10 µm) in the copepod Eurytemora affinis collected in the Seine estuary (France) and identified using epifluorescence microscopy and Raman microspectroscopy. In order to calibrate the methodology, copepods obtained from cultures were used. Firstly, we labelled three types of MPs (i.e., Polystyrene, Polyethylene, and Polylactic acid) with Nile Red and confirmed their ingestion by E. affinis with epifluorescence microscopy. Considering the convenient detection of Nile Red labelled MPs using epifluorescence observation, we tried to pair this method with Raman microspectroscopy. For this, we developed an enzymatic digestion method consisting of copepods digestion using Proteinase K followed by sonication in order to fragment their cuticle. The lysate was then vacuum filtered on black polycarbonate membrane filters that were the most appropriate for epifluorescence microscopy. Potential MPs were dyed with Nile Red directly on the filter, which allowed a relatively rapid visual detection. However, results showed that black polycarbonate membrane filters induced a significant background fluorescence during Raman identification of MPs and hence particles smaller than 10 µm could not be characterized. In this case, we were not able to link staining method with micro-Raman for the size range of MPs targeted in this study. Thus, aluminum oxide filters were tested, and staining method was replaced by a classical observation with stereomicroscopic magnifier to delimit areas of observation for Raman microscopic identification. Aluminum oxide filters induced less fluorescence, allowing the detection of MPs (as small as 1 µm diameter) on copepods from laboratory cultures exposed with MPs. We applied this method on copepods collected in the natural environment. Within a pool of 20 copepods of three replicates, we identified 17 MPs (average of 0.28 MPs/copepod) composed of eight different polymer types and six colors. These MPs corresponded to 59% of fibres with 14.1 ± 9.4 µm diameter and 391.6 ± 600.4 µm length along with 41% of fragments with an average diameter of 13.2 µm ± 9.5 µm. This study reports a novel approach to detect the presence of small particles of MPs ingested by copepods in the natural environment.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42589607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-12DOI: 10.3389/fenvc.2022.834191
A. S. Wright, M. Doblin, P. Scanes
Constructed wetlands (CWs) are an effective means to treat nutrient and sediment pollution in urban stormwater runoff to minimise impact on receiving waterways. Maintenance of devices is recognised as a major contributing factor to performance. There is a lack of evidence-based guidance on maintenance activities to optimise treatment, due to a paucity of data from long-term field studies into CW performance before and after maintenance. In this study, the nutrient and sediment removal efficiency (% RE) of a CW was evaluated by calculating removal efficiencies of nitrogen (N), phosphorus (P) and total suspended sediment (TSS) following a long-term sampling program under baseflow and event flow conditions. Sampling was carried out before, during and after maintenance. Maintenance involved removing all aquatic vegetation and 200–300 mm of sediments over a 3-week period, aiming to improve the wetland’s performance. Assessment of dissolved and particulate nutrient fractions allowed a comprehensive investigation into drivers of nutrient removal efficiency. Under baseflow conditions differences in inflow and outflow pollutant concentrations were used to calculate removal efficiency and pollutant loads were used during event flow conditions. Before maintenance, during baseflow conditions the wetland was removing total N (36% RE) but exporting total P (-52% RE) and total sediment (-94% RE). During event-flow conditions all target pollutants were being removed (total N 63% RE, total P 25% RE and TSS 69% RE). phosphorusDuring maintenance, the device continued to remove total N (18% RE) but the physical disturbance of the maintenance resulted in mass export of total P (-120% RE) and total sediment (−2,000% RE) over a short time period, effectively undoing previous treatment. After maintenance, during baseflow conditions, the wetlands’ ability to treat total N decreased (28% RE), improved for total P (1% RE), and became a chronic source of suspended sediment (−127% RE). During event flow conditions, total N was no longer being treated (−19%) but total P and total suspended sediment were being retained (74%, 80% RE respectively). This study showed that the physical disturbance resulting from large-scale maintenance activities can potentially reverse years’ worth of treatment if not adequately planned and carried out with suitable controls.
{"title":"Improper Maintenance Activities Alter Benefits of Urban Stormwater Treatment in a Temperate Constructed Wetland in NSW, Australia","authors":"A. S. Wright, M. Doblin, P. Scanes","doi":"10.3389/fenvc.2022.834191","DOIUrl":"https://doi.org/10.3389/fenvc.2022.834191","url":null,"abstract":"Constructed wetlands (CWs) are an effective means to treat nutrient and sediment pollution in urban stormwater runoff to minimise impact on receiving waterways. Maintenance of devices is recognised as a major contributing factor to performance. There is a lack of evidence-based guidance on maintenance activities to optimise treatment, due to a paucity of data from long-term field studies into CW performance before and after maintenance. In this study, the nutrient and sediment removal efficiency (% RE) of a CW was evaluated by calculating removal efficiencies of nitrogen (N), phosphorus (P) and total suspended sediment (TSS) following a long-term sampling program under baseflow and event flow conditions. Sampling was carried out before, during and after maintenance. Maintenance involved removing all aquatic vegetation and 200–300 mm of sediments over a 3-week period, aiming to improve the wetland’s performance. Assessment of dissolved and particulate nutrient fractions allowed a comprehensive investigation into drivers of nutrient removal efficiency. Under baseflow conditions differences in inflow and outflow pollutant concentrations were used to calculate removal efficiency and pollutant loads were used during event flow conditions. Before maintenance, during baseflow conditions the wetland was removing total N (36% RE) but exporting total P (-52% RE) and total sediment (-94% RE). During event-flow conditions all target pollutants were being removed (total N 63% RE, total P 25% RE and TSS 69% RE). phosphorusDuring maintenance, the device continued to remove total N (18% RE) but the physical disturbance of the maintenance resulted in mass export of total P (-120% RE) and total sediment (−2,000% RE) over a short time period, effectively undoing previous treatment. After maintenance, during baseflow conditions, the wetlands’ ability to treat total N decreased (28% RE), improved for total P (1% RE), and became a chronic source of suspended sediment (−127% RE). During event flow conditions, total N was no longer being treated (−19%) but total P and total suspended sediment were being retained (74%, 80% RE respectively). This study showed that the physical disturbance resulting from large-scale maintenance activities can potentially reverse years’ worth of treatment if not adequately planned and carried out with suitable controls.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44136465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-04DOI: 10.3389/fenvc.2022.874342
Fudong Liu, X. Weng, Qiguang Dai
Department of Civil, Environmental, and Construction Engineering, Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT), NanoScience Technology Center (NSTC), University of Central Florida, Orlando, FL, United States, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, China
{"title":"Editorial: Secondary Pollution in the Environmental Pollution Control Process: Production, Environmental Risks and Reduction","authors":"Fudong Liu, X. Weng, Qiguang Dai","doi":"10.3389/fenvc.2022.874342","DOIUrl":"https://doi.org/10.3389/fenvc.2022.874342","url":null,"abstract":"Department of Civil, Environmental, and Construction Engineering, Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT), NanoScience Technology Center (NSTC), University of Central Florida, Orlando, FL, United States, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, China","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48006693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-22DOI: 10.3389/fenvc.2022.844633
C. Goedecke, P. Eisentraut, K. Altmann, A. Elert, C. Bannick, M. Ricking, Nathan Obermaier, Anne-Katrin Barthel, T. Schmitt, M. Jekel, U. Braun
An investigation of microplastic (MP) occurrence in a municipal wastewater treatment plant (WWTP) effluent with tertiary treatment was carried out. Representative sample volumes of 1 m3 were taken by applying a fractionated filtration method (500, 100, and 50 µm mesh sizes). The detection of MP mass fractions by thermal extraction desorption–gas chromatography/mass spectrometry (TED-GC/MS) was achieved without the previously required additional sample pretreatment for the first time. Different types of quantification methods for the evaluation of TED-GC/MS data were tested, and their accuracy and feasibility have been proven for real samples. Polyethylene, polystyrene, and polypropylene were identified in effluent samples. The polymer mass content varied significantly between 5 and 50 mg m−3. A correlation between the MP load and the quantity of suspended matter in the WWTP effluents, particle size distribution, particle type, and operation day (i.e., weekday, season, and capacity) was not found. It can be concluded that a meaningful assessment of WWTPs requires a comprehensive sampling campaign with varying operation conditions. Graphical Abstract
{"title":"Development of a Routine Screening Method for the Microplastic Mass Content in a Wastewater Treatment Plant Effluent","authors":"C. Goedecke, P. Eisentraut, K. Altmann, A. Elert, C. Bannick, M. Ricking, Nathan Obermaier, Anne-Katrin Barthel, T. Schmitt, M. Jekel, U. Braun","doi":"10.3389/fenvc.2022.844633","DOIUrl":"https://doi.org/10.3389/fenvc.2022.844633","url":null,"abstract":"An investigation of microplastic (MP) occurrence in a municipal wastewater treatment plant (WWTP) effluent with tertiary treatment was carried out. Representative sample volumes of 1 m3 were taken by applying a fractionated filtration method (500, 100, and 50 µm mesh sizes). The detection of MP mass fractions by thermal extraction desorption–gas chromatography/mass spectrometry (TED-GC/MS) was achieved without the previously required additional sample pretreatment for the first time. Different types of quantification methods for the evaluation of TED-GC/MS data were tested, and their accuracy and feasibility have been proven for real samples. Polyethylene, polystyrene, and polypropylene were identified in effluent samples. The polymer mass content varied significantly between 5 and 50 mg m−3. A correlation between the MP load and the quantity of suspended matter in the WWTP effluents, particle size distribution, particle type, and operation day (i.e., weekday, season, and capacity) was not found. It can be concluded that a meaningful assessment of WWTPs requires a comprehensive sampling campaign with varying operation conditions. Graphical Abstract","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48394437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-02-24DOI: 10.3389/fenvc.2022.797966
Osamu Udagawa, S. Hirano
The existence of membrane-less organelles in the cells has been known for a relatively long time. Of the membrane-less organelles, stress granules, processing bodies, and PML-NBs have been intensively investigated in relation to arsenic. The membrane-less organelles, which concentrate biomolecules (proteins, nucleic acids), have recently been shown to self-organize by means of phase separation/transition. These biomolecular condensates (membrane-less organelles) can provide local enhancement of the efficiency of specific reactions. The biomolecular condensates have attracted dramatic attention over the last decade because highly organized biochemical complexes in the cell have long been understood by the membrane-dependent compartmentalization. In this mini review, we highlight the initiation of phase separation for each biomolecular condensate in which arsenic could be involved. We further reflect on the adequacy of the arsenic-dependent ROS levels for the formation of biomolecular condensates. These perspectives led us to re-evaluate the biological action of arsenic from a biophysical and bio-rheological point of view.
{"title":"How Arsenic, an Inorganic Pollutant, is Involved in the Physiology of Biomolecular Condensates in the Cell","authors":"Osamu Udagawa, S. Hirano","doi":"10.3389/fenvc.2022.797966","DOIUrl":"https://doi.org/10.3389/fenvc.2022.797966","url":null,"abstract":"The existence of membrane-less organelles in the cells has been known for a relatively long time. Of the membrane-less organelles, stress granules, processing bodies, and PML-NBs have been intensively investigated in relation to arsenic. The membrane-less organelles, which concentrate biomolecules (proteins, nucleic acids), have recently been shown to self-organize by means of phase separation/transition. These biomolecular condensates (membrane-less organelles) can provide local enhancement of the efficiency of specific reactions. The biomolecular condensates have attracted dramatic attention over the last decade because highly organized biochemical complexes in the cell have long been understood by the membrane-dependent compartmentalization. In this mini review, we highlight the initiation of phase separation for each biomolecular condensate in which arsenic could be involved. We further reflect on the adequacy of the arsenic-dependent ROS levels for the formation of biomolecular condensates. These perspectives led us to re-evaluate the biological action of arsenic from a biophysical and bio-rheological point of view.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42184356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-02-14DOI: 10.3389/fenvc.2022.784385
L. Artigue, V. Chavagnac, C. Destrigneville, B. Ferron, C. Cathalot
Lithium (Li) and strontium (Sr) are two economically relevant chemical elements whose oceanic biogeochemical cycles are not fully constrained. In particular, how they disperse and behave from hydrothermal sources into the water column is understudied while hydrothermal systems on the global mid-ocean ridge network (∼67,000 km) represent one of the main sources of Li. This study aims to provide new insights on the dissolved Li (DLi) and Sr (DSr) behavior in the water column. Here, we present for the first time the DLi and DSr elemental and isotopic (δ7Li, and 87Sr/86Sr) profiles from six casts distributed over the Lucky Strike hydrothermal vent field (LSHF, Mid-Atlantic Ridge). The DLi and DSr results reflect a hydrothermal contribution to the water column up to ∼300 m above the seafloor that can be quantified by up to 10% based on the DLi dataset. For increasing hydrothermal contribution the δ7Li values of the water column become heavier most likely due to mineral–seawater interactions, i.e., manganese oxide formed during the mixing of hydrothermal fluid and seawater. Contrarily to the DLi, DSr, and δ7Li datasets, the hydrothermal contribution to the water column is not evidenced by the 87Sr/86Sr ratios that fall within the range of oligotrophic oceanic waters. Surprisingly, some geographically distant casts display at the same depth identical DLi and DSr concentrations or similar δ7Li signatures. We attribute these features to the current dynamics above the LSHF, suggesting that the hydrothermal signature of the western casts can overprint those of the eastern and center casts in less than 1 h at the LSHF km-scale. Overall, this study highlights that 1) as for many elements, DLi, DSr, and δ7Li can be used to track the hydrothermal signature to the water column at a km-scale whereas 87Sr/86Sr cannot, 2) local currents play a major role in advecting the hydrothermal contribution away from the hydrothermal sources, and 3) mineral–seawater interaction processes are at play during the mixing between hydrothermal fluid and seawater and impact the δ7Li hydrothermal signature. Our study suggests that chemical tracers of hydrothermal input have to be chosen depending on the spatial scale of the studied area.
{"title":"Tracking the Lithium and Strontium Isotope Signature of Hydrothermal Plume in the Water Column: A Case Study at the EMSO-Azores Deep-Sea Observatory","authors":"L. Artigue, V. Chavagnac, C. Destrigneville, B. Ferron, C. Cathalot","doi":"10.3389/fenvc.2022.784385","DOIUrl":"https://doi.org/10.3389/fenvc.2022.784385","url":null,"abstract":"Lithium (Li) and strontium (Sr) are two economically relevant chemical elements whose oceanic biogeochemical cycles are not fully constrained. In particular, how they disperse and behave from hydrothermal sources into the water column is understudied while hydrothermal systems on the global mid-ocean ridge network (∼67,000 km) represent one of the main sources of Li. This study aims to provide new insights on the dissolved Li (DLi) and Sr (DSr) behavior in the water column. Here, we present for the first time the DLi and DSr elemental and isotopic (δ7Li, and 87Sr/86Sr) profiles from six casts distributed over the Lucky Strike hydrothermal vent field (LSHF, Mid-Atlantic Ridge). The DLi and DSr results reflect a hydrothermal contribution to the water column up to ∼300 m above the seafloor that can be quantified by up to 10% based on the DLi dataset. For increasing hydrothermal contribution the δ7Li values of the water column become heavier most likely due to mineral–seawater interactions, i.e., manganese oxide formed during the mixing of hydrothermal fluid and seawater. Contrarily to the DLi, DSr, and δ7Li datasets, the hydrothermal contribution to the water column is not evidenced by the 87Sr/86Sr ratios that fall within the range of oligotrophic oceanic waters. Surprisingly, some geographically distant casts display at the same depth identical DLi and DSr concentrations or similar δ7Li signatures. We attribute these features to the current dynamics above the LSHF, suggesting that the hydrothermal signature of the western casts can overprint those of the eastern and center casts in less than 1 h at the LSHF km-scale. Overall, this study highlights that 1) as for many elements, DLi, DSr, and δ7Li can be used to track the hydrothermal signature to the water column at a km-scale whereas 87Sr/86Sr cannot, 2) local currents play a major role in advecting the hydrothermal contribution away from the hydrothermal sources, and 3) mineral–seawater interaction processes are at play during the mixing between hydrothermal fluid and seawater and impact the δ7Li hydrothermal signature. Our study suggests that chemical tracers of hydrothermal input have to be chosen depending on the spatial scale of the studied area.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47834978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-02-14DOI: 10.3389/fenvc.2022.767202
Marianna Pinzone, Alice Cransveld, G. De Boeck, J. Shrivastava, E. Tessier, S. Bérail, Joseph G. Schnitzler, D. Amouroux, K. Das
Seafood has a great ecological and nutritional value for human and wildlife communities. However, accumulation of mercury (Hg) in fish is a concern to animal and human health. There is a crucial need to understand Hg speciation in marine organisms through controlled feeding experiments. This study represents a first assessment of the biological processes that may influence Hg bioaccumulation and dynamics in a marine predatory fish. We conducted a feeding experiment to investigate the dynamics of MeHg and iHg, as well as Hg isotopes in the liver and muscles of captive juvenile seabass (Dicentrarchus labrax). Three groups of juvenile seabass were fed in captivity during 3 weeks of acclimatization and 6 weeks of experiment. Each group was fed with pellets containing environmentally relevant MeHg concentrations (Control, 200 and 500 ng g−1 dw). We monitored the evolution of MeHg and iHg concentrations as well as Hg isotopic values in liver and muscle. We determined Hg dynamics with respect to the contamination level in the fish diet. Muscle δ202Hg and Δ199Hg turnover rates ranged between 33 and 14 days (Low diet) to 5 and 9 days (Mod diet). Liver δ202Hg and Δ199Hg turnover rates ranged between 3 and 7 days (Low diet) to 3 and 2 days (Mod diet), respectively. Hg species concentrations and δ202Hg varied over time between diet groups and tissues, showing the occurrence of internal mass-dependent fractionation (MDF). No significant intra-tissue and temporal Hg mass-independent fractionation (MIF) was observed. The results of our experiment are strongly in favor of the existence of MeHg demethylation in a coastal predatory fish exposed to low to moderate concentrations of environmental Hg. The decrease over time of δ202Hg in muscle of seabass from the most contaminated diet was accompanied by a temporal increase in iHg, pointing to possible Hg detoxification processes occurring in this tissue when dietary Hg exposure is high. The absence of Hg MDF and different turnover between muscle and liver in seabass exposed to 500 ng Hg g−1 confirmed that Hg speciation and bioaccumulation in juvenile fish are controlled by Hg levels and speciation in their diet.
海鲜对人类和野生动物社区具有巨大的生态和营养价值。然而,鱼类中汞的积累是动物和人类健康的一个问题。迫切需要通过控制饲养实验来了解海洋生物中汞的物种形成。这项研究首次评估了可能影响汞在海洋掠食性鱼类中的生物累积和动态的生物过程。我们进行了一项饲养实验,以研究圈养幼年鲈鱼(Dicentrarchus labrax)肝脏和肌肉中甲基汞和汞的动态,以及汞同位素。在3周的驯化和6周的实验期间,三组幼年鲈鱼被圈养喂养。每组喂食含有环境相关甲基汞浓度的颗粒(对照组,200和500 ng g−1 dw)。我们监测了肝脏和肌肉中甲基汞和iHg浓度的演变以及汞同位素值。我们确定了汞与鱼类饮食中污染水平的关系。肌肉δ202Hg和Δ199Hg的转换率在33和14天(低日粮)到5和9天(Mod日粮)之间。肝脏δ202Hg和Δ199Hg的转换率分别在3和7天(低日粮)到3和2天(Mod日粮)之间。汞物种浓度和δ202Hg在饮食组和组织之间随时间变化,显示出内部质量依赖性分馏(MDF)的发生。未观察到显著的组织内和时间内汞质量无关分级(MIF)。我们的实验结果强烈支持暴露于中低浓度环境汞的沿海掠食性鱼类存在甲基汞去甲基化。随着时间的推移,受污染最严重的饮食中鲈鱼肌肉中δ202Hg的减少伴随着iHg的暂时增加,这表明当饮食中汞暴露量高时,该组织可能会发生汞解毒过程。暴露于500 ng Hg g−1的鲈鱼不存在汞MDF,肌肉和肝脏之间的周转率不同,这证实了幼鱼体内汞的物种形成和生物累积受其饮食中汞水平和物种形成的控制。
{"title":"Dynamics of Dietary Mercury Determined by Mercury Speciation and Isotopic Composition in Dicentrarchus labrax","authors":"Marianna Pinzone, Alice Cransveld, G. De Boeck, J. Shrivastava, E. Tessier, S. Bérail, Joseph G. Schnitzler, D. Amouroux, K. Das","doi":"10.3389/fenvc.2022.767202","DOIUrl":"https://doi.org/10.3389/fenvc.2022.767202","url":null,"abstract":"Seafood has a great ecological and nutritional value for human and wildlife communities. However, accumulation of mercury (Hg) in fish is a concern to animal and human health. There is a crucial need to understand Hg speciation in marine organisms through controlled feeding experiments. This study represents a first assessment of the biological processes that may influence Hg bioaccumulation and dynamics in a marine predatory fish. We conducted a feeding experiment to investigate the dynamics of MeHg and iHg, as well as Hg isotopes in the liver and muscles of captive juvenile seabass (Dicentrarchus labrax). Three groups of juvenile seabass were fed in captivity during 3 weeks of acclimatization and 6 weeks of experiment. Each group was fed with pellets containing environmentally relevant MeHg concentrations (Control, 200 and 500 ng g−1 dw). We monitored the evolution of MeHg and iHg concentrations as well as Hg isotopic values in liver and muscle. We determined Hg dynamics with respect to the contamination level in the fish diet. Muscle δ202Hg and Δ199Hg turnover rates ranged between 33 and 14 days (Low diet) to 5 and 9 days (Mod diet). Liver δ202Hg and Δ199Hg turnover rates ranged between 3 and 7 days (Low diet) to 3 and 2 days (Mod diet), respectively. Hg species concentrations and δ202Hg varied over time between diet groups and tissues, showing the occurrence of internal mass-dependent fractionation (MDF). No significant intra-tissue and temporal Hg mass-independent fractionation (MIF) was observed. The results of our experiment are strongly in favor of the existence of MeHg demethylation in a coastal predatory fish exposed to low to moderate concentrations of environmental Hg. The decrease over time of δ202Hg in muscle of seabass from the most contaminated diet was accompanied by a temporal increase in iHg, pointing to possible Hg detoxification processes occurring in this tissue when dietary Hg exposure is high. The absence of Hg MDF and different turnover between muscle and liver in seabass exposed to 500 ng Hg g−1 confirmed that Hg speciation and bioaccumulation in juvenile fish are controlled by Hg levels and speciation in their diet.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43275726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-24DOI: 10.3389/fenvc.2021.795632
Juan Sánchez-Castellón, Iván D. Urango-Cardenas, Germán Enamorado-Montes, Saudith Burgos-Núñez, J. Marrugo-Negrete, S. Díez
Discharge of metals into the environment generates significant impact upon human health and biological cycles. Some microorganisms such as fungi are known for their high metal adsorption capacity. The aim of this work was to evaluate the capacity for Penicillium sp. molds in the removal of Pb, Cd, and Hg from aqueous solutions by isolating the fungal strain from an artisanal gold mine soil. The biosorption experiments showed that optimum conditions for metal removal were noted at 150 min, acidic pH (4–5), 60 °C, and 2 g of biomass. The accomplished removal was 92.4% for Pb, 80% for Cd, and 99.6% for Hg, at a concentration of 51.5 mg/L. Kinetic analyses and isotherms best fit the pseudo–second-order and Langmüir models, respectively. Infrared spectra show functional groups (–OH, –NH, C-N, C-H, N-H, and C=O) that play an essential role in the adsorption of Pb, Hg, and Cd on fungal biomass.
{"title":"Removal of Mercury, Cadmium, and Lead Ions by Penicillium sp.","authors":"Juan Sánchez-Castellón, Iván D. Urango-Cardenas, Germán Enamorado-Montes, Saudith Burgos-Núñez, J. Marrugo-Negrete, S. Díez","doi":"10.3389/fenvc.2021.795632","DOIUrl":"https://doi.org/10.3389/fenvc.2021.795632","url":null,"abstract":"Discharge of metals into the environment generates significant impact upon human health and biological cycles. Some microorganisms such as fungi are known for their high metal adsorption capacity. The aim of this work was to evaluate the capacity for Penicillium sp. molds in the removal of Pb, Cd, and Hg from aqueous solutions by isolating the fungal strain from an artisanal gold mine soil. The biosorption experiments showed that optimum conditions for metal removal were noted at 150 min, acidic pH (4–5), 60 °C, and 2 g of biomass. The accomplished removal was 92.4% for Pb, 80% for Cd, and 99.6% for Hg, at a concentration of 51.5 mg/L. Kinetic analyses and isotherms best fit the pseudo–second-order and Langmüir models, respectively. Infrared spectra show functional groups (–OH, –NH, C-N, C-H, N-H, and C=O) that play an essential role in the adsorption of Pb, Hg, and Cd on fungal biomass.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42019010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}