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1.
Environ Pollut ; 292(Pt A): 118255, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34600061

RESUMEN

Seven organophosphate esters (OPEs) in atmospheric particles and surface seawater were observed during a cruise in the western South China Sea (SCS) in 2014. The median concentrations of ∑OPEs were 688 pg/m3 and 5.55 ng/L for particle and seawater samples, respectively. Total OPEs were dominated by tris(1-chloro-2-propyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP). The spatial distribution of OPEs indicates that the OPEs in particle phase were mainly influenced by the air masses originating from China, Indochina Peninsula and Malay Archipelago, showing the significant contribution of anthropogenic sources from these regions. Significant positive correlations between Tri-n-butylphosphate (TnBP) and organic carbon (P < 0.05) in particle phase over the western SCS suggests that it might be a potential tracer for the source regions of Indochina Peninsula and Malay Archipelago. The spatial distribution of OPEs in seawater was contributed by freshwater inputs associating with variations of human activities as well as salinity. Seawater pollution levels of OPEs in the eastern coast of Vietnam were increased compared to those measured in the northern SCS. The loadings of ∑OPEs transported to the vast area of western SCS vias atmospheric deposition and air-seawater gas exchange were estimated to be 59 tons/year and 105 tons/year, respectively. This work highlights the importance of transport processes and air-seawater interface behavior of OPEs in the oceanic area.


Asunto(s)
Retardadores de Llama , China , Monitoreo del Ambiente , Ésteres , Retardadores de Llama/análisis , Humanos , Organofosfatos , Agua de Mar
2.
Environ Pollut ; 292(Pt A): 118337, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34644624

RESUMEN

Marine microplastics have received considerable attention as a global environmental issue. However, despite the constant accumulation of microplastics in the ocean, their transport processes and mechanisms remain poorly understood. This study investigated microplastics in the sediments of seagrass meadows and nearby regions without seagrass along the Shandong coast and found that the sediment in the seagrass meadows was a sink for microplastics. Subsequently, we evaluated the influence of eelgrass (Zostera marina), a common coastal seagrass, on the sedimentation of suspended polystyrene microplastics. The results showed that 0.5, 1.0, and 2.0 g/L eelgrass leaves decreased the abundance of microplastics in seawater in a dose-dependent manner over a period of 3-48 h under shaking conditions at 120 rpm at 22 °C. After 48 h of shaking, microplastic abundances in the 0.5, 1.0, and 2.0 g/L eelgrass groups significantly decreased by 46.9%, 53.1%, and 88.4%, respectively. Microplastics can adhere to eelgrass leaves and form biofilms, which promoted the formation of white floc that traps the suspended microplastics, causing them to sink. Furthermore, two epiphytic bacteria (Vibrio and Exiguobacterium) isolated from the eelgrass leaves decreased the abundances of suspended microplastics by 95.7% and 94.5%, respectively, in 48 h by accelerating the formation of biofilms on the microplastics. Therefore, eelgrass and its epiphytic bacteria facilitated the sinking of microplastics and increased the accumulation of microplastics in the sediments of seagrass meadows in coastal regions.


Asunto(s)
Zosteraceae , Bacterias , Microplásticos , Plásticos , Agua de Mar
3.
Environ Pollut ; 292(Pt B): 118275, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34626717

RESUMEN

The lack of standardization on the definition and methods in microplastic (MP) research has limited the overall interpretation and intercomparison of published data. This has presented different solutions to assess the presence of these pollutants in the natural environment, bringing the science forward. Microplastics have been reported worldwide across different biological levels and environmental compartments. In the Mediterranean Sea, numerous research efforts have been dedicated to defining the MP pollution levels. The reported MP concentrations are comparable to those found in the convergence zone of ocean gyres, pointing to this basin as one of the world's greatest plastic accumulation areas. However, to what extent are the data produced limited by the methods? Here, we present the results of a systematic review of MP research methods and occurrence targeting the seawater and sediment bodies of the Mediterranean Sea. Based on this dataset, we 1) assess the discrepancies and similarities in the methods, 2) analyze how these differences affect the reported concentrations, and 3) identify the limitations of the data produced for the Mediterranean Sea. Moreover, we reaffirm the pressing need of developing a common reporting terminology, and call for international collaboration between Mediterranean countries, especially with North African countries, to provide a complete picture of the MP pollution status in this basin.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Mar Mediterráneo , Plásticos , Agua de Mar , Contaminantes Químicos del Agua/análisis
4.
Environ Pollut ; 292(Pt B): 118329, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34634406

RESUMEN

Since the last decade, several studies have reported the presence and effects of pharmaceutical residues in the marine environment, especially those of the antihypertensive class, such as losartan. However, there is little knowledge about the physiological effects of losartan in marine invertebrates regarding its behavior under possible coastal ocean acidification scenarios. The objective of this study was to evaluate biological effects on marine organisms at different levels of the biological organization caused by the compound losartan in water and sediment under coastal ocean acidification scenarios. Water and sediment samples were collected at five sites around the Santos Submarine Sewage outfall (SSO) and two sites around the Guarujá Submarine Sewage Outfall (GSO). Losartan was found in concentrations ranging from

Asunto(s)
Agua de Mar , Contaminantes Químicos del Agua , Animales , Antihipertensivos , Organismos Acuáticos , Concentración de Iones de Hidrógeno , Losartán/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
5.
Sci Total Environ ; 804: 150208, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34798741

RESUMEN

European sea bass (Dicentrarchus labrax) migrate towards habitats where salinity can reach levels over 60‰, notably in Mediterranean lagoons. D. labrax are genetically subdivided in Atlantic and Mediterranean lineages and have evolved in slightly different salinities. We compared Atlantic and West-Mediterranean populations regarding their capacity to tolerate hypersalinity with a focus on the involvement of the intestine in solute-driven water reabsorption. Fish were analyzed following a two-week transfer from seawater (SW, 36‰) to either SW or hypersaline water (HW, 55‰). Differences among lineages were observed in posterior intestines of fish maintained in SW regarding NKA activities and mRNA expressions of nkaα1a, aqp8b, aqp1a and aqp1b with systematic higher levels in Mediterranean sea bass. High salinity transfer triggered similar responses in both lineages but at different magnitudes which may indicate slight different physiological strategies between lineages. High salinity transfer did not significantly affect the phenotypic traits measured in the anterior intestine. In the posterior intestine however, the size of enterocytes and NKA activity were higher in HW compared to SW. In this tissue, nka-α1a, nkcc2, aqp8ab and aqp8aa mRNA levels were higher in HW compared to SW as well as relative protein expression of AQP8ab. For aqp1a, 1b, 8aa and 8b, an opposite trend was observed. The sub-apical localization of AQP8ab in enterocytes suggests its role in transepithelial water reabsorption. Strong apical NKCC2/NCC staining indicates an increased Na+ and Cl- reuptake by enterocytes which could contribute to solute-coupled water reuptake in cells where AQP8ab is expressed.


Asunto(s)
Lubina , Animales , Lubina/metabolismo , Branquias/metabolismo , Intestinos , Osmorregulación , Salinidad , Agua de Mar , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
6.
Sci Total Environ ; 802: 149807, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34450439

RESUMEN

It is expected that by 2050 human population will exceed nine billion leading to increased pressure on marine ecosystems. Therefore, it is conjectured various levels of ecosystem functioning starting from individual to population-level, species distribution, food webs and trophic interaction dynamics will be severely jeopardized in coming decades. Ocean warming and acidification are two prime threats to marine biota, yet studies about their cumulative effect on marine fish and shellfishes are still in its infancy. This review assesses existing information regarding the interactive effects of global environmental factors like warming and acidification in the perspective of marine capture fisheries and aquaculture industry. As climate change continues, distribution pattern of species is likely to be altered which will impact fisheries and fishing patterns. Our work is an attempt to compile the existing literatures in the biological perspective of the above-mentioned stressors and accentuate a clear outline of knowledge in this subject. We reviewed studies deciphering the biological consequences of warming and acidification on fish and shellfishes in the light of a molecule to ecosystem perspective. Here, for the first time impacts of these two global environmental drivers are discussed in a holistic manner taking into account growth, survival, behavioural response, prey predator dynamics, calcification, biomineralization, reproduction, physiology, thermal tolerance, molecular level responses as well as immune system and disease susceptibility. We suggest urgent focus on more robust, long term, comprehensive and ecologically realistic studies that will significantly contribute to the understanding of organism's response to climate change for sustainable capture fisheries and aquaculture.


Asunto(s)
Ecosistema , Agua de Mar , Animales , Cambio Climático , Calentamiento Global , Humanos , Concentración de Iones de Hidrógeno , Océanos y Mares , Mariscos
7.
Sci Total Environ ; 802: 149787, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34464796

RESUMEN

This study aimed to determine the effect of the climatic change on the phototrophic communities of hypersaline microbial mats. Ocean acidification and warming were simulated alone and together on microbial mats placed into mesocosms. As expected, the temperature in the warming treatments increased by 4 °C from the initial temperature. Surprisingly, no significance difference was observed between the water pH of the different treatments despite of a decrease of 0.4 unit pH in the water reserves of acidification treatments. The salinity increased on the warming treatments and the dissolved oxygen concentration increased and was higher on the acidification treatments. A total of 37 pigments were identified belonging to chlorophylls, carotenes and xanthophylls families. The higher abundance of unknown chlorophyll molecules called chlorophyll derivatives was observed in the acidification alone treatment with a decrease in chlorophyll a abundance. This change in pigmentary composition was accompanied by a higher production of bound extracellular carbohydrates but didn't affect the photosynthetic efficiency of the microbial mats. A careful analysis of the absorption properties of these molecules indicated that these chlorophyll derivatives were likely bacteriochlorophyll c contained in the chlorosomes of green anoxygenic phototroph bacteria. Two hypotheses can be drawn from these results: 1/ the phototrophic communities of the microbial mats were modified under acidification treatment leading to a higher relative abundance of green anoxygenic bacteria, or 2/ the highest availability of CO2 in the environment has led to a shift in the metabolism of green anoxygenic bacteria being more competitive than other phototrophs.


Asunto(s)
Bacterioclorofilas , Cambio Climático , Clorofila , Clorofila A , Humanos , Concentración de Iones de Hidrógeno , Agua de Mar
8.
J Hazard Mater ; 421: 126711, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34332489

RESUMEN

Understanding the interactions between oil and other particles in shoreline can help determine the environmental risk and cleanup strategy after oil spill. Nevertheless, far less has been known regarding the impact of aged MPs on oil behavior in the shoreline environment. In this study, the aging course of polyethylene (PE) in shaking seawater and ultraviolet (UV) radiation conditions was investigated. The seawater aging mainly affected the physical properties of MPs, increasing its surface pores and hydrophilicity. UV aging significantly affected both the physical and chemical properties of MPs, which increased its hydrophilicity and crystallinity, decreased its mean particle size and introduced oxygen-containing functional groups onto MPs. The two-dimensional correlation spectroscopy (2D COS) analysis confirmed the evolution of oxygen-containing functional groups from C-O to CO. The effects of aged MPs on oil behavior in water-sand system were further explored. The oil remaining percentages were non-linearly changed with the increasing aging degree of MPs. The particle size of the aqueous phase after washing was inversely related to the oil remaining percentage. Further FTIR analysis revealed that C-O and C-H functional groups played an important role in the process of oil adsorbed on MPs.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Polietileno , Agua de Mar , Contaminantes Químicos del Agua/análisis
9.
J Environ Manage ; 301: 113922, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34731960

RESUMEN

While water is a key resource required to sustain life, freshwater sources and aquifers are being depleted at an alarming rate. As a mitigation strategy, saline water desalination is commonly used to supplement the available water resources beyond direct water supply. This is achieved through effective advanced water purification processes enabled to handle complex matrix of saline wastewater. Membrane technology has been extensively evaluated for water desalination. This includes the use of reverse osmosis (RO) (the most mature membrane technology for desalination), pervaporation (PV), electrodialysis (ED), membrane distillation (MD), and membrane crystallization (MCr). Though nanofiltration (NF) is not mainly applied for desalination purposes, it is included in the reviewed processes because of its ability to reach 90% salt rejection efficiency for water softening. However, its comparison with other technologies is not provided since NF cannot be used for removal of NaCl during desalination. Remarkably, membrane processes remain critically affected by several challenges including membrane fouling. Moreover, capital expenditure (CAPEX) and operating expenditure (OPEX) are the key factors influencing the establishment of water desalination processes. Therefore, this paper provides a concise and yet comprehensive review of the membrane processes used to desalt saline water. Furthermore, the successes and failures of each process are critically reviewed. Finally, the CAPEX and OPEX of these water desalination processes are reviewed and compared. Based on the findings of this review, MD is relatively comparable to RO in terms of process performance achieving 99% salt rejections. Also, high salt rejections are reported on ED and PV. The operation and maintenance (O&M) costs remain lower in ED. Notably, the small-scale MD OPEX falls below that of RO. However, the large-scale O&M in MD is rarely reported due to its slow industrial growth, thus making RO the most preferred in the current water desalination markets.


Asunto(s)
Agua de Mar , Purificación del Agua , Costos y Análisis de Costo , Ósmosis , Tecnología
10.
J Hazard Mater ; 421: 126780, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34358974

RESUMEN

The microbial colonization profiles on microplastics (MPs) in marine environments have recently sparked global interest. However, many studies have characterized plastisphere microbiomes without considering the ecological processes that underly microbiome assembly. Here, we carried out a three-timepoint exposure experiment at 1-, 4-, and 8-week and investigated the colonization dynamics for polyethylene, polypropylene, polystyrene, polyvinyl chloride, and acrylonitrile-butadiene-styrene MP pellets in natural coastal water. Using high-throughput sequencing of 16S rRNA, we found diversity and evenness were higher (p < 0.05) in the plastisphere communities than those in seawater, and microorganisms colonizing were co-influenced by environmental factors, polymer types, and exposure duration. Functional potential and co-occurrence network analysis revealed that MP exposure enriched the xenobiotic biodegradation potential and reduced the complexity of the MP microbial network. Simultaneously, null-model analyses indicated that stochastic processes contributed a bigger role than deterministic processes in shaping plastisphere microbial community structure with dispersal limitations contributing to a greater extent to microbial succession trajectories. These results implied the plastic surface had a more important role as a raft onto which microbes attach rather than selectively recruiting plastic-specific microbial colonizers. Our work strengthened the understanding of the ecological mechanisms by which microbial community patterns are controlled during colonization by plastic-associated microbes.


Asunto(s)
Microbiota , Plásticos , Biodegradación Ambiental , ARN Ribosómico 16S/genética , Agua de Mar
11.
Chemosphere ; 286(Pt 1): 131588, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34293555

RESUMEN

Non-targeted analysis for the monitoring of organic pollutants resulting from agricultural and industrial practices, plastics and pharmaceutical products of seawater from the Mar Menor lagoon (SE Spain) is proposed using dispersive liquid-liquid microextraction (DLLME) and gas chromatography-mass spectrometry (GC-MS). Initially, a home-made MS database including 118 environmental organic pollutants, whose presence in different ecosystems has already been reported, was created. The analytical method was applied for the analysis of 42 samples and a total of 18 pollutants were detected and identified. Samples were obtained from different sites around the Mar Menor in three sampling campaigns, enabling the assessment of impact of rain on the input of the detected chemicals and their distribution. In addition, this methodology was validated using a standard mixture containing 54 of the environmental pollutants included in the database, allowing the quantification of the 9 of the identified compounds (dibutyl phthalate, diisobutyl phthalate, diethyl phthalate, bis(2-ethylhexyl) phthalate, anthracene, 2-methylnaphthalene, hexachlorocyclopentadiene, bis(2-ethylhexyl) adipate and oleamide) with concentration between 3 and 271 µg L-1.


Asunto(s)
Contaminantes Ambientales , Microextracción en Fase Líquida , Ecosistema , Contaminantes Ambientales/análisis , Cromatografía de Gases y Espectrometría de Masas , Agua de Mar
12.
Chemosphere ; 286(Pt 1): 131514, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34311394

RESUMEN

A baseline study on anthropogenic radioactivity in the Namibian marine ecosystem, which is part of the northern Benguela upwelling system, known as one of the most productive ocean areas in the world, has been performed. A scientific cruise carried out in 2014 covering inshore and offshore areas, exhibiting different oceanographic features, has provided a basis for better understanding the distributions, ratios and inventories of six anthropogenic radionuclides (90Sr, 137Cs, 238Pu, 239Pu, 240Pu and 241Am) in seawater. Although 3H was also measured, due to extremely low levels, its behaviour was not studied. The main source of 90Sr, 137Cs, 239Pu, 240Pu and 241Am in the samples analysed was proven to be global fallout, a finding further confirmed by 240Pu/239Pu and 90Sr/137Cs ratios. Furthermore, the 238Pu SNAP-9A satellite accident signal was confirmed once again through the determination of the 238Pu/239+240Pu activity ratio. Inshore and offshore samples showed different patterns due to the unique oceanographic features of this upwelling system. The levels of anthropogenic radionuclides, comprehensively assessed for the first time in this region, are comparable with the few existing data and filled a critical gap for the Southern Atlantic Ocean.


Asunto(s)
Plutonio , Monitoreo de Radiación , Contaminantes Radiactivos del Agua , Radioisótopos de Cesio/análisis , Ecosistema , Namibia , Plutonio/análisis , Agua de Mar , Radioisótopos de Estroncio , Contaminantes Radiactivos del Agua/análisis
13.
Chemosphere ; 286(Pt 1): 131609, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34315074

RESUMEN

The systematic analysis of groundwater in the Greek island of Skiathos revealed a seasonal increase of total mercury concentrations after the extensive groundwater abstraction during the busy and heavily touristic summer months. This contamination was accompanied by a corresponding increase of the chloride content of groundwater, attributed to seawater intrusion into the freshwater-depleted aquifer within mercury-rich bedrock. The effects of elevated concentrations of chloride anions in the mobilization of mercury and its speciation were addressed by geochemical equilibrium modeling, considering cinnabar (HgS) as the mineral source of mercury. Adsorption onto hydrous ferric oxide (Fe2O3·H2O) was a necessary ingredient of the geochemical model for bringing the calculated concentrations in agreement with field measurements, after optimization of the cinnabar/adsorbent mass ratio to a value of 4.9 × 10-8. The speciation of mercury was found to depend on the acidity and redox status as well as on the chloride content of groundwater. Mercury concentrations in the groundwater of Skiathos rise above the World Health Organization limit of 1 µg L-1 for a seawater intrusion higher than 3 %, with HgCl2 being the dominant species followed by HgClOH, HgCl3- and HgCl42-. The assumed concentration of dissolved organic matter in groundwater had a negligible impact on the mercury speciation and its mobilization by chloride.


Asunto(s)
Agua Subterránea , Mercurio , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Agua Dulce , Mercurio/análisis , Agua de Mar , Contaminantes Químicos del Agua/análisis
14.
Chemosphere ; 286(Pt 1): 131626, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34346333

RESUMEN

Extraction uranium from complicated aqueous solutions (seawater and nuclear wastewater) has been promoting the development of multi-functional adsorbents with high adsorption capacities and high selectivity. Here, we proposed a co-immobilization approach to preparing uranium adsorbents. Due to specific recognition and binding between functional groups, bayberry tannin (BT) and hydrous titanium oxide (HTO) were co-immobilized onto nano collagen fibrils (NCFs). The adsorption performances of NCFs-HTO-BT to uranium were systematically investigated in two aqueous systems, including nuclear wastewater and seawater. Results proved that NCFs-HTO-BT possessed the remarkable adsorption capacities and affinities for uranium in wastewater (393.186 mg g-1) and spiked seawater (14.878 mg g-1) with the uranium concentration of 320 mg g-1 and 8 mg g-1, respectively. Based on characteristic analysis of the adsorbent before and after uranium adsorption, the hydroxyl groups of HTO, the adjacent phenolic hydroxyl groups of BT, and nitrogen-containing and oxygen-containing functional groups of NCFs were active sites for uranium adsorption.


Asunto(s)
Myrica , Uranio , Adsorción , Agua de Mar , Taninos , Titanio , Aguas Residuales
15.
Chemosphere ; 286(Pt 1): 131677, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34346336

RESUMEN

China is considered to account for nearly a third of all plastic waste discharging from land to the ocean. To overall assess microplastic pollution status in Chinese coastal and marginal seas, this study summarized the abundance and characteristics of microplastics in the seawater, sediments and marine organisms. The results showed that the abundance of microplastics in the seawater of four major seas of China was 0.13-545 items/m³, and microplastic abundance in the sediments from the estuaries was 20-7900 items/kg, which are at middle level or even lower than those detected in other countries. By contrast, severe microplastic pollution was recorded in the estuaries, suggesting that plastic waste and microplastic interception measures should be conducted on the rivers to prevent the input of microplastics. In addition, microplastics were widely detected in marine fishes, mollusks, zooplankton, mammals and birds, which highlights the potential impacts of microplastic pollution on the whole marine ecosystem. Compared to the dry season, higher microplastic abundance was found in the rainy season, revealing that plastic waste recycling should be strengthened before the onset of rainy season. We suggest that all countries respond actively to the ubiquitous microplastic pollution through practical policies and measures to prevent microplastics from further damaging the marine ecosystem.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , China , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Océanos y Mares , Plásticos , Agua de Mar , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
16.
Chemosphere ; 286(Pt 2): 131675, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34358890

RESUMEN

Caffeine has been identified as emerging contaminant of concern due to its widespread occurrence in the aquatic environment and potential to be biologically active. Recently, these concerns have been translated in an increasing research on its occurrence and effects on biota. However, there is still a limited knowledge on seawater matrices and the implications of caffeine presence in coastal and marine ecosystems are not fully known. The present review aims to fill these knowledge gaps, analysing the existing literature regarding the occurrence, effects and potential risks of caffeine residues to coastal ecosystems, contributing to the risk assessment of this psychoactive drug in the aquatic environment. The analysed literature reported caffeine concentrations in the coastal ecosystems, raising high concerns about the potential adverse impacts on the ecological safety and human health. Caffeine has been found in tissues from coastal and marine biota including microalgae, coral reefs, bivalves and fish due to bioaccumulation after chronic, long-term exposures in a contaminated environment. Additionally, caffeine residues had been demonstrated to have adverse impacts on aquatic organisms, at environmentally realistic concentrations, inducing oxidative stress and lipid peroxidation, neurotoxicity, changing energy reserves and metabolic activity, affecting reproduction and development and, in some cases, causing mortality. Considering the increasing adverse impacts of caffeine pollution in the coastal environment, this review highlights the urgent need to minimize the increasing load of caffeine to the aquatic ecosystems; being imperative the implementation of scientific programs and projects to classify effectively the caffeine as a high-priority environmentally hazardous emerging pollutant.


Asunto(s)
Bivalvos , Contaminantes Químicos del Agua , Animales , Cafeína/análisis , Cafeína/toxicidad , Ecosistema , Humanos , Agua de Mar , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
17.
Chemosphere ; 286(Pt 2): 131711, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34340115

RESUMEN

The levels, fate, and potential sources of 22 organochlorine pesticides (OCPs) in coral tissues and the surrounding air-seawater system from the South China Sea (SCS) were elucidated for the first time. ∑22OCPs (total concentration of 22 OCPs) (16.1-223 pg L-1) was relatively higher in coastal seawater than in offshore seawater, which may be the widespread influence of coastal pollution inputs under the western boundary current. The atmospheric ∑22OCPs were predominantly distributed in the gas phase (48.0-2264 pg m-3) and were mainly influenced by continental air mass origins. The air-seawater exchange of selected OCPs showed that OCPs tended to migrate from the atmosphere to seawater. The distribution of ∑22OCPs in coral tissues (0.02-52.2 ng g-1 dw) was significantly correlated with that in air samples, suggesting that OCPs may have a migration pattern of atmosphere-ocean corals in the SCS. Corals exhibited higher bioaccumulation ability (Log BAFs: 2.42-7.41) for OCPs. Source analysis showed that the new application of technical Chlordanes (CHLs) was primarily responsible for the current levels of CHLs in the surrounding environment over the SCS, while historical residues were the primary sources of other OCPs.


Asunto(s)
Antozoos , Hidrocarburos Clorados , Plaguicidas , Animales , China , Monitoreo del Ambiente , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Agua de Mar
18.
Chemosphere ; 286(Pt 3): 131751, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34399257

RESUMEN

Oil spills in Arctic marine environments are expected to increase concurrently with the expansion of shipping routes and petroleum exploitation into previously inaccessible ice-dominated regions. Most research on oil biodegradation focusses on the bulk oil, but the fate of the water-accommodated fraction (WAF), mainly composed of toxic aromatic compounds, is largely underexplored. To evaluate the bacterial degradation capacity of such dissolved aromatics in Greenlandic seawater, microcosms consisting of 0 °C seawater polluted with WAF were investigated over a 3-month period. With a half-life (t1/2) of 26 days, m-xylene was the fastest degraded compound, as measured by gas chromatography - mass spectrometry. Substantial slower degradation was observed for ethylbenzene, naphthalenes, phenanthrene, acenaphthylene, acenaphthene and fluorenes with t1/2 of 40-105 days. Colwellia, identified by 16S rRNA gene sequencing, was the main potential degrader of m-xylene. This genus occupied up to 47 % of the bacterial community until day 10 in the microcosms. Cycloclasticus and Zhongshania aliphaticivorans, potentially utilizing one-to three-ringed aromatics, replaced Colwellia between day 10 and 96 and occupied up to 6 % and 23 % of the community, respectively. Although most of the WAF can ultimately be eliminated in microcosms, our results suggest that the restoration of an oil-impacted Arctic environment may be slow as most analysed compounds had t1/2 of over 2-3 months and the detrimental effects of a spill towards the marine ecosystem likely persist during this time.


Asunto(s)
Contaminación por Petróleo , Petróleo , Contaminantes Químicos del Agua , Regiones Árticas , Biodegradación Ambiental , Ecosistema , Gammaproteobacteria , Hidrocarburos , Contaminación por Petróleo/análisis , ARN Ribosómico 16S/genética , Agua de Mar , Agua , Contaminantes Químicos del Agua/análisis
19.
Sci Total Environ ; 803: 150002, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34482143

RESUMEN

Dimethyl sulfide (DMS) produced by marine algae represents the largest natural emission of sulfur to the atmosphere. The oxidation of DMS is a key process affecting new particle formation that contributes to the radiative forcing of the Earth. In this study, atmospheric DMS and its major oxidation products (methanesulfonic acid, MSA; non-sea-salt sulfate, nss-SO42-) and particle size distributions were measured at King Sejong station located in the Antarctic Peninsula during the austral spring-summer period in 2018-2020. The observatory was surrounded by open ocean and first-year and multi-year sea ice. Importantly, oceanic emissions and atmospheric oxidation of DMS showed distinct differences depending on source regions. A high mixing ratio of atmospheric DMS was observed when air masses were influenced by the open ocean and first-year sea ice due to the abundance of DMS producers such as pelagic phaeocystis and ice algae. However, the concentrations of MSA and nss-SO42- were distinctively increased for air masses originating from first-year sea ice as compared to those originating from the open ocean and multi-year sea ice, suggesting additional influences from the source regions of atmospheric oxidants. Heterogeneous chemical processes that actively occur over first-year sea ice tend to accelerate the release of bromine monoxide (BrO), which is the most efficient DMS oxidant in Antarctica. Model-estimates for surface BrO confirmed that high BrO mixing ratios were closely associated with first-year sea ice, thus enhancing DMS oxidation. Consequently, the concentration of newly formed particles originated from first-year sea ice, which was a strong source area for both DMS and BrO was greater than from open ocean (high DMS but low BrO). These results indicate that first-year sea ice plays an important yet overlooked role in DMS-induced new particle formation in polar environments, where warming-induced sea ice changes are pronounced.


Asunto(s)
Cubierta de Hielo , Agua de Mar , Regiones Antárticas , Sulfuros/análisis
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120474, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34689088

RESUMEN

A new fluorescent sensing microtiter plate (MTP) was developed for high sensitivity monitoring of anthracene in seawater samples. For this purpose, two ternary complexes of Tb(III) ions with dibenzoylmethane and neocuproine [Tb(DBM)2(MePhen)] or with dibenzoylmethane and bathocuproine [Tb(DBM)2(PhMePhen)] were synthesized. Elemental analysis, energy dispersive X-ray analysis, X-ray diffraction, infrared and ultraviolet-visible emission, and thermal analysis were conducted on the Tb(III) complexes. The limits of detection (DL) were 0.14 and 1.05 µmol L-1 for [Tb(DBM)2(MePhen)] and [Tb(DBM)2(PhMePhen)], respectively. [Tb(DBM)2(PhMePhen)] MTP is embedded in a membrane made of cellulose acetate. The first high-throughput anthracene sensor MTP, based on [Tb(DBM)2(PhMePhen)] sensor showed a linear range, from 0.2 to 20 µmol L-1. [Tb(DBM)2(PhMePhen)] MTP was validated for accurate and precise monitoring of anthracene using gas chromatography. The selectivity of the [Tb(DBM)2(PhMePhen)] MTP toward anthracene was examined. The data indicated that [Tb(DBM)2(PhMePhen)] MTP is suitable for rapid and direct detection of anthracene.


Asunto(s)
Antracenos , Terbio , Iones , Agua de Mar , Difracción de Rayos X
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