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1.
J Water Health ; 22(6): 1044-1052, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38935455

RESUMO

Current methods for testing water for faecal contamination rely on the culture of faecal indicator bacteria (FIB; Escherichia coli and Enterococci) that take 24-48 h, which leads to delays in taking proactive measures and poses a risk to public health. More rapid methods are therefore required. Here, we have tested a rapid, portable assay (Bacterisk) that detects the bacterial biomarker endotoxin in 30 min to quantify the bacterial biomass present, to evaluate 159 coastal water samples and to compare the results with the traditional culture of FIB. There was a significant correlation between the Bacterisk data given in endotoxin risk (ER) units and FIB culture that could accurately distinguish between poor and sufficient or good quality bathing water using the EU bathing directive values. Receiver operating characteristic analysis was used to determine the optimal ER threshold for coastal water samples, and the area under the curve was 0.9176 with a p-value of <0.0001. The optimal threshold was 7,300 ER units with a sensitivity of 95.45% and a specificity of 83.48%. In conclusion, we have shown that the Bacterisk assay provides a rapid and easy-to-use in situ method to assess bathing water quality.


Assuntos
Endotoxinas , Monitoramento Ambiental , Fezes , Água do Mar , Fezes/microbiologia , Endotoxinas/análise , Monitoramento Ambiental/métodos , Água do Mar/microbiologia , Medição de Risco , Biomarcadores/análise , Microbiologia da Água , Praias/normas , Escherichia coli/isolamento & purificação , Qualidade da Água
2.
Mar Pollut Bull ; 204: 116516, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38833951

RESUMO

This study investigates the presence of microplastics (MPs) in seawater, sediments, and organisms along the coastal areas of Da Nang, Vietnam. The results obtained revealed MP concentrations ranging from 111 to 304 MPs/L in seawater and 2267 to 4600 MPs/kg in sediment. In organisms such as oysters, mussels, crabs, snails, and fish, MP levels ranged from 1.8 to 17.3 MPs/g (wet weight). Fiber MPs were found to be predominant across seawater, sediment, and organisms. The study identified eight, ten, and eleven types of MPs in seawater, sediment, and organisms, respectively, with Nylon, Polytetrafluoroethylene (PTFE), and Ethylene vinyl alcohol (EVOH) being the most prevalent. Notably, MP concentrations were significantly higher in benthic organisms such as oysters, mussels, and crabs compared to fish (t-test, p < 0.05), suggesting habitat dependency. Similar concentrations, shapes, and types of MPs in seawater, sediments, and organisms demonstrate a tendency for MP accumulation in aquatic organisms within the marine environment.


Assuntos
Organismos Aquáticos , Monitoramento Ambiental , Microplásticos , Água do Mar , Poluentes Químicos da Água , Animais , Vietnã , Poluentes Químicos da Água/análise , Água do Mar/química , Microplásticos/análise , Sedimentos Geológicos/química , Braquiúros , Peixes , Bivalves , Ostreidae , Caramujos
3.
Biofouling ; 40(5-6): 366-376, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855912

RESUMO

This research introduces an Artificial Intelligence (AI) based model designed to concurrently optimize energy supply management, biocide dosing, and maintenance scheduling for heat exchangers. This optimization considers energetic, technical, economic, and environmental considerations. The impact of biofilm on heat exchangers is assessed, revealing a 41% reduction in thermal efficiency and a 113% increase in flow frictional resistance of the fluid compared to the initial state. Consequently, the pump's power consumption, required to maintain hydraulic conditions, rises by 9%. The newly developed AI model detects the point at which the heat exchanger's performance begins to decline due to accumulating dirt, marking day 44 of experimentation as the threshold to commence the antifouling biocide dosing. Leveraging this AI model to monitor heat exchanger efficiency represents an innovative approach to optimizing antifouling biocide dosing and reduce the environmental impact stemming from industrial plants.


Assuntos
Inteligência Artificial , Biofilmes , Incrustação Biológica , Desinfetantes , Água do Mar , Água do Mar/química , Biofilmes/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Modelos Teóricos
4.
Ecotoxicol Environ Saf ; 281: 116622, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38917586

RESUMO

Microplastics (MPs) pose one of the major environmental threats to marine organisms and ecosystems on a global scale. The present study investigated MPs in surface water, beach sediments, and fish in two coastal areas of Bangladesh namely Cox's Bazar and Kuakata. The MPs were identified and characterized using three different techniques, including the binocular microscope, the ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy), and SEM-EDS (Scanning Electron Microscopy- Energy Dispersive Spectroscopy). The number of MPs in seawater was 10.1 ± 3.10 and 8.52 ± 3.92 items/100 L and in beach sediment, 13.2 ± 3.68 and 9.48 ± 3.63 items/100 g in Cox's Bazar and Kuakata, respectively. In fish samples, the abundance of MPs was 7.82 ± 1.28 and 6.82 ± 1.87 items/individual species of Cox's Bazar and Kuakata, respectively, where the highest quantities of MP were found in Euthynnus affinisand Sillago sihama and the lowest in Terapon jarbua and Pampus chinensisin Cox's Bazar and Kuakata, respectively. The number of MPs in GITs (Gastrointestinal tracts) was 1.63 ± 0.991 and 1.25 ± 0.546 items/g GIT and in BW (Body Weight) were 0.042 ± 0.014 and 0.037 ± 0.014 items/g BW in Cox's Bazar and Kuakata, respectively. There revealed a positive correlation between MP abundance and GIT weight and body weight in fish species. MPs were predominantly fiber-shaped, white/transparent, and small size. The most common MP polymers were polyethylene and polypropylene. SEM images of MPs demonstrate surface roughness, cracks, mechanical weathering and oxidative weathering, demonstrating their ongoing environmental exposure. The EDS spectrum unearthed that the MPs contained several elements (C, N, O, Na, Al, Fe, and Si). Findings from this study might be useful in coastal plastic particle management and to mitigate the potential risks associated with them.


Assuntos
Ecossistema , Monitoramento Ambiental , Peixes , Microplásticos , Água do Mar , Poluentes Químicos da Água , Bangladesh , Microplásticos/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental/métodos , Água do Mar/química , Sedimentos Geológicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Varredura
5.
Chemosphere ; 359: 142334, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38759811

RESUMO

This study presents a baseline evaluation of the distribution, human and ecotoxicological risk, and the potential interactions of fluoride and boron in the water-sediment interface in 25 locations from incredible Red Sea tourist destinations. Results showed comparable levels of B and F in the water and sediments with previous literature. Significant positive correlation was found between B and F (r = 0.57; P<0.01). Based on the sediment/liquid partition coefficient (Kd), F is more likely to be released from the sediment into seawater (logKd< 3) than B (3< logKd< 4). pH and alkalinity may affect water-sediment interactions of B and F, respectively, while SO42- and Cl- ions had no significant effect on adsorption ability of F and B. The majority of minerals had average saturation Index (SI) > 1 referring to the over saturation of seawater with these minerals and their inability to dissolve. The formation of CF, FAP, and CFAP may be related to the high correlation between Fw (r = 0.928, P< 0.01; r = 0.527, P< 0.01; r = 0.608, P< 0.01) and Bw (r = 0.38, P< 0.05; r = 0.38, P< 0.05; r = 0.397, P< 0.05). Total hazard quotient (THQ) for children and adults were <1, revealing no health risks from exposure to B and F through ingestion and skin contact while swimming. The risk characterization ratio; RCRmix(MEC/PNEC) showed high short-term risks to aquatic organisms. Further investigations might emphasis on emerging mitigation strategies to address these concerns.


Assuntos
Boro , Monitoramento Ambiental , Fluoretos , Sedimentos Geológicos , Água do Mar , Poluentes Químicos da Água , Boro/análise , Boro/química , Poluentes Químicos da Água/análise , Medição de Risco , Egito , Água do Mar/química , Fluoretos/análise , Sedimentos Geológicos/química , Humanos , Oceano Índico , Íons , Adulto
6.
J Environ Manage ; 360: 121192, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781880

RESUMO

The global demand for valuable metals and minerals necessitates the exploration of alternative, sustainable approaches to mineral recovery. Seawater mining has emerged as a promising option, offering a vast reserve of minerals and an environmentally friendly alternative to land-based mining. Among the various techniques, Nanofiltration (NF) has gained significant attention as a preliminary treatment step in Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes. This study focused on the potential of two underexplored commercial polyamide based NF membranes, Synder NFX and Vontron VNF1, with enhanced divalent over monovalent separation factors, in optimizing the extraction of magnesium hydroxide (Mg(OH)2) from seawater and seawater reverse osmosis (SWRO) brines. The research encompassed a thorough characterization of the membranes utilizing advanced physic-chemical analytical techniques, followed by rigorous experimental assessments using synthetic seawater and SWRO brine in concentration configuration. The findings highlighted the superior selectivity of NFX for magnesium recovery from SWRO brine and the promising concentration factors of VNF1 for seawater treatment. Cross-validation of experimental data with a mathematical model demonstrated the model's reliability as a process design tool in predicting membrane performance. A comprehensive techno-economic evaluation demonstrates the potential of NFX, operating optimally at 23 bar pressure and 70% permeate recovery rate, to yield an estimated annual revenue of 5.683 M€/yr through Mg(OH)2 production from SWRO brine for a plant with a nominal capacity of 0.8 Mm3/y. This research shed light on the promising role of NF membranes in enhancing mineral recovery taking benefit of their separation factors and emphasizes the economic viability of leveraging NF technology for maximizing magnesium recovery from seawater and SWRO brines.


Assuntos
Filtração , Magnésio , Água do Mar , Água do Mar/química , Magnésio/química , Filtração/métodos , Membranas Artificiais , Osmose , Sais
7.
Environ Pollut ; 355: 124230, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38810679

RESUMO

Industrial and urban activities are major contributors to metal contamination in coastal systems, often impacting the physiology, distribution and diversity of marine invertebrates. This study assessed metal contaminations in sediments, seawater, algae and invertebrates across four armoured systems (harbours) and two natural sites along the south coast of South Africa. Bioaccumulation factors such as Biosediment (BSAF), Biowater (BWAF), Bioaccumulation (BAF) and bioremediation of metals by invertebrate bioindicators were also determined. Spatial variation in metal concentrations were observed, however, bioaccumulation of metals was site and species-specific. Invertebrates bioaccumulated higher metal concentrations in armoured than natural sites, with filter feeders exhibiting higher concentrations than grazers. Among filter feeders, Octomeris angulosa and Crassostrea gigas bioaccumulated elevated aluminium (Al), arsenic (As), chromium (Cr), zinc (Zn) and copper (Cu), while, Perna perna accumulated elevated nickel (Ni), cadmium (Cd) and lead (Pb). Among grazers, Siphonaria serrata and Scutellastra longicosta bioaccumulated elevated Al, Cr, Cd, cobalt (Co), Cu, Ni and Zn. Bioaccumulation factors indicated that (As, Ni, Zn) were bioaccumulated by algae, and invertebrates from sediment (BSAF>1) and from seawater (BWAF>1). Additionally, invertebrates bioaccumulated metals from their prey item, algae as indicated by (BAF>1). Arsenic Cd and Pb in invertebrates were above the maximum limit set for human consumption by various regulatory bodies. Our findings underscore the significant role of coastal invertebrates in bioaccumulating and bioremediating metals, suggesting a natural mechanism for water quality enhancement, especially in urbanised coastal areas.


Assuntos
Organismos Aquáticos , Monitoramento Ambiental , Sedimentos Geológicos , Invertebrados , Poluentes Químicos da Água , Animais , África do Sul , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Invertebrados/metabolismo , Monitoramento Ambiental/métodos , Medição de Risco , Organismos Aquáticos/metabolismo , Bioacumulação , Metais/metabolismo , Água do Mar/química , Metais Pesados/metabolismo , Metais Pesados/análise
8.
J Environ Sci Health B ; 59(7): 399-416, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38785435

RESUMO

Secondary metabolites produced by Bacillus species from marine sources encompass a variety of compounds such as lipopeptides, isocoumarins, polyketides, macrolactones, polypeptides and fatty acids. These bioactive substances exhibit various biological activities, including antibiotic, antifungal, antiviral, and antitumor properties. This study aimed to isolate and identify a particular species of Bacillus from marine water and organisms that can produce bioactive secondary metabolites. Among the 73 Bacillus isolates collected, only 5 exhibited antagonistic activity against various viral and bacterial pathogens. The active isolates were subjected to 16S rRNA sequencing to determine their taxonomical affiliation. Among them, Bacillus tequilensis CCASU-2024-66 strain no. 42, with the accession number ON 054302 in GenBank, exhibited the highest inhibitory potential. It displayed an inhibition zone of 21 mm against Bacillus cereus while showing a minimum zone of inhibition of 9 mm against Escherichia coli and gave different inhibition against pathogenic fungi, the highest inhibition zone 15 mm against Candida albicans but the lowest inhibition zone 10 mm was against Botrytis cinerea, Fusarium oxysporum. Furthermore, it demonstrated the highest percentage of virucidal effect against the Newcastle virus and influenza virus, with rates of 98.6% and 98.1%, respectively. Furthermore, GC-MS analysis was employed to examine the bioactive substance components, specifically focusing on volatile and polysaccharide compounds. Based on these results, Bacillus tequilensis strain 42 may have the potential to be employed as an antiviral agent in poultry cultures to combat Newcastle and influenza, two extremely destructive viruses, thus reducing economic losses in the poultry production sector. Bacteria can be harnessed for the purpose of preserving food and controlling pathogenic fungi in both human and plant environments. Molecular docking for the three highly active derivatives 2,3-Butanediol, 2TMS, D-Xylopyranose, 4TMS, and Glucofuranoside, methyl 2,3,5,6-tetrakis-O-(trimethylsilyl) was carried out against the active sites of Bacillus cereus, Listeria monocytogenes, Candida albicans, Newcastle virus and influenza virus. The data obtained from molecular docking is highly correlated with that obtained from biology. Moreover, these highly active compounds exhibited excellent proposed ADMET profile.


Assuntos
Bacillus , Cromatografia Gasosa-Espectrometria de Massas , Bacillus/química , Bacillus/metabolismo , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Água do Mar/microbiologia , RNA Ribossômico 16S/genética , Fungos/efeitos dos fármacos , Botrytis/efeitos dos fármacos
9.
J Hazard Mater ; 474: 134754, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38820750

RESUMO

The ubiquitous and adverse effects of estrogens have aroused global concerns. Natural and synthetic estrogens in 255 water samples from the southern Bohai Sea were analyzed over three years. Total estrogen concentrations were 11.0-268 ng/L in river water and 1.98-99.7 ng/L in seawater, with bisphenol A (BPA) and 17α-ethynylestradiol (EE2) being the predominant estrogens, respectively. Estrogen showed the highest concentrations in summer 2018, followed by spring 2021 and spring 2019, which was consistent with the higher estrogen flux from rivers during summer. Higher estrogen concentrations in 2021 than in 2019 were driven by the higher level of BPA, an additive used in personal protective equipment. Estrogen exhibited higher concentrations in the southern coast of the Yellow River Delta and the northeastern coast of Laizhou bay due to the riverine input and aquaculture. Estrogens could disturb the normal endocrine activities of organisms and edict high ecological risks (90th simulated RQT > 1.0) to aquatic organisms, especially to fish. EE2 was the main contributor of estrogenic potency and ecological risk, which requires special concern. This is the first comprehensive study of estrogen spatiotemporal variations and risks in the Bohai Sea, providing insights into the environmental behavior of estrogens in coastal regions.


Assuntos
Monitoramento Ambiental , Estrogênios , Água do Mar , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Medição de Risco , Estrogênios/análise , Água do Mar/química , Água do Mar/análise , China , Animais , Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , Rios/química , Fenóis/análise , Fenóis/toxicidade , Compostos Benzidrílicos/análise , Etinilestradiol/análise , Oceanos e Mares , Estações do Ano
10.
Environ Toxicol Chem ; 43(6): 1442-1457, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38695731

RESUMO

Microplastic pollution threatens some of the world's most iconic locations for marine biodiversity, including the remote Galápagos Islands, Ecuador. Using the Galápagos penguin (Spheniscus mendiculus) as a sentinel species, the present study assessed microplastics and suspected anthropogenic cellulose concentrations in surface seawater and zooplankton near Santa Cruz and Galápagos penguin colonies (Floreana, Isabela, Santiago), as well as in penguin potential prey (anchovies, mullets, milkfish) and penguin scat. On average, 0.40 ± 0.32 microplastics L-1 were found in surface seawater (<10 µm; n = 63 L), while 0.003, 0.27, and 5.12 microplastics individual-1 were found in zooplankton (n = 3372), anchovies (n = 11), and mullets (n = 6), respectively. The highest concentration (27 microplastics individual-1) was observed in a single milkfish. Calculations based on microplastics per gram of prey, in a potential diet composition scenario, suggest that the Galápagos penguin may consume 2881 to 9602 microplastics daily from prey. Despite this, no microplastics or cellulose were identified in 3.40 g of guano collected from two penguins. Our study confirms microplastic exposure in the pelagic food web and endangered penguin species within the UNESCO World Heritage site Galápagos Islands, which can be used to inform regional and international policies to mitigate plastic pollution and conserve biodiversity in the global ocean. Environ Toxicol Chem 2024;43:1442-1457. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Celulose , Monitoramento Ambiental , Cadeia Alimentar , Microplásticos , Spheniscidae , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Equador , Zooplâncton/efeitos dos fármacos , Água do Mar/química
11.
Mar Pollut Bull ; 203: 116470, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38728956

RESUMO

We investigated the health conditions of the Mediterranean mussel Mytilus galloprovincialis recruited in the CO2 vents system of Castello Aragonese at Ischia Island (Mediterranean Sea). Individuals of M. galloprovincialis were sampled in three sites along the pH gradient (8.10, 7.7 and up to <7.4). Untargeted metabolomics and biochemical endpoints related to energetic metabolism, oxidative stress/damage, neurotoxicity and immune defense were analyzed. Corrosion of the valves occurred at low pH. A separation of the metabolome was observed along the pH gradient. Metabolites belonging to amino acids, nucleosides, lipids and organic osmolytes were significantly reduced in the organisms from the most acidified sites. The content of reactive oxygen species and the activity of glutathione peroxidase were reduced in organisms from the acidified sites compared to ambient pH, and no oxidative damage was induced. Overall results suggested the presence of an energy cost underpinning long-term survival in acidified conditions for this species.


Assuntos
Metabolismo Energético , Mytilus , Estresse Oxidativo , Animais , Concentração de Íons de Hidrogênio , Água do Mar/química , Mar Mediterrâneo , Metaboloma , Espécies Reativas de Oxigênio/metabolismo , Acidificação dos Oceanos
12.
Sci Total Environ ; 942: 173585, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38810735

RESUMO

Marine ecosystem has been experiencing multiple stressors caused by anthropogenic activities, including ocean acidification (OA) and nickel (Ni) pollution. Here, we examined the individual/combined effects of OA (pCO2 1000 µatm) and Ni (6 µg/L) exposure on a marine copepod Tigriopus japonicus for six generations (F1-F6), followed by one-generation recovery (F7) in clean seawater. Ni accumulation and several important phenotypic traits were measured in each generation. To explore within-generation response and transgenerational plasticity, we analyzed the transcriptome profile for the copepods of F6 and F7. The results showed that Ni exposure compromised the development, reproduction and survival of copepods during F1-F6, but its toxicity effects were alleviated by OA. Thus, under OA and Ni combined exposure, due to their antagonistic interaction, the disruption of Ca2+ homeostasis, and the inhibition of calcium signaling pathway and oxytocin signaling pathway were not found. However, as a cost of acclimatization/adaption potential to long-term OA and Ni combined exposure, there was a loss of transcriptome plasticity during recovery, which limited the resilience of copepods to previously begin environments. Overall, our work fosters a comprehensive understanding of within- and transgenerational effects of climatic stressor and metal pollution on marine biota.


Assuntos
Copépodes , Níquel , Água do Mar , Transcriptoma , Poluentes Químicos da Água , Animais , Copépodes/efeitos dos fármacos , Copépodes/fisiologia , Níquel/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Água do Mar/química , Concentração de Íons de Hidrogênio , Acidificação dos Oceanos
13.
Ecotoxicology ; 33(3): 239-252, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38573560

RESUMO

Despite the prevalence of discharge of large volumes of heavy-metal-bearing seawater from coal-fired power plants into adjacent seas, studies on the associated ecological risks remain limited. This study continuously monitored concentrations of seven heavy metals (i.e. As, Cd, Cr, Cu, Hg, Pb, and Zn) in surface seawater near the outfall of a coal-fired power plant in Qingdao, China over three years. The results showed average concentrations of As, Cd, Cr, Cu, Hg, Pb, and Zn of 2.63, 0.33, 2.97, 4.63, 0.008, 0.85, and 25.00 µg/L, respectively. Given the lack of data on metal toxicity to local species, this study investigated species composition and biomass near discharge outfalls and constructed species sensitivity distribution (SSD) curves with biological flora characteristics. Hazardous concentrations for 5% of species (HC5) for As, Cd, Cr, Cu, Hg, Pb, and Zn derived from SSDs constructed from chronic toxicity data for native species were 3.23, 2.22, 0.06, 2.83, 0.66, 4.70, and 11.07 µg/L, respectively. This study further assessed ecological risk of heavy metals by applying the Hazard Quotient (HQ) and Joint Probability Curve (JPC) based on long-term heavy metal exposure data and chronic toxicity data for local species. The results revealed acceptable levels of ecological risk for As, Cd, Hg, and Pb, but unacceptable levels for Cr, Cu, and Zn. The order of studied heavy metals in terms of ecological risk was Cr > Cu ≈ Zn > As > Cd ≈ Pb > Hg. The results of this study can guide the assessment of ecological risk at heavy metal contaminated sites characterized by relatively low heavy metal concentrations and high discharge volumes, such as receiving waters of coal-fired power plant effluents.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Monitoramento Ambiental/métodos , Cádmio , Chumbo , Metais Pesados/toxicidade , Água do Mar , Medição de Risco , Centrais Elétricas , China , Carvão Mineral , Solo , Poluentes do Solo/análise
14.
J Hazard Mater ; 470: 134169, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38565022

RESUMO

Microplastic (MP) pollution poses a significant threat to marine ecosystem and seafood safety. However, comprehensive and comparable assessments of MP profiles and their ecological and health in Chinese farming oysters are lacking. This study utilized laser infrared imaging spectrometer (LDIR) to quantify MPs in oysters and its farming seawater at 18 sites along Chinese coastlines. Results revealed a total of 3492 MPs in farmed oysters and seawater, representing 34 MP types, with 20-100 µm MP fragments being the dominant. Polyurethane (PU) emerged as the predominant MP type in oysters, while polysulfones were more commonly detected in seawater. Notably, oysters from the Bohai Sea exhibited a higher abundance of MPs (13.62 ± 2.02 items/g) and estimated daily microplastic intake (EDI, 2.14 ± 0.26 items/g/kg·bw/day), indicating a greater potential health risk in the area. Meanwhile, seawater from the Yellow Sea displayed a higher level (193.0 ± 110.7 items/L), indicating a greater ecological risk in this region. Given the pervasiveness and abundance of PU and its high correlation with other MP types, we proposed PU as a promising indicator for monitoring and assessing the risk MP pollution in mariculture in China. These findings provide valuable insights into the extent and characteristics of MP pollution in farmed oysters and seawater in China.


Assuntos
Aquicultura , Monitoramento Ambiental , Microplásticos , Ostreidae , Água do Mar , Poluentes Químicos da Água , Animais , Água do Mar/análise , China , Poluentes Químicos da Água/análise , Ostreidae/química , Microplásticos/análise , Medição de Risco
15.
J Environ Manage ; 358: 120888, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615399

RESUMO

Oil dispersion, a crucial process in oil transport, involves the detachment of oil droplets from slicks and their introduction into the water column, influencing subsequent oil migration and transformation. This study examines oil dispersion, considering characteristics, stability, and mechanisms, while evaluating the impact of dispersants and salinity. Results show the significant role of surfactant type in dispersants on oil dispersion characteristics, with anionic surfactants exhibiting higher sensitivity to salinity changes compared to nonionic surfactants. The dispersion efficiency varies with salinity, with anionic surfactants performing better in low salinity (<20‰) and nonionic surfactants showing superior performance at 30-35‰ salinities. Rheological analysis illustrates the breakup and coalescence of oil droplets within the shear rates of breaking waves. An increase in interfacial film rigidity impedes the coalescence of oil droplets, contributing to the dynamic stability of the oil-water hybrid system. The use of GM-2, a nonionic dispersant, results in the formation of a solid-like interface, characterized by increased elastic modulus, notably at 20‰ salinity. However, stable droplet size distribution (DSD) at 35‰ salinity for 60 h suggests droplets can remain dispersed in seawater. The enhancement of stability of oil dispersion is interpreted as the result of two mechanisms: stabilizing DSD and developing the strength of viscoelastic interfacial film. These findings offer insights into oil dispersion dynamics, highlighting the importance of surfactant selection and salinity in governing dispersion behavior, and elucidating mechanisms underlying dispersion stability.


Assuntos
Tensoativos , Tensoativos/química , Poluição por Petróleo , Salinidade , Reologia , Petróleo , Água do Mar/química
16.
Sci Total Environ ; 927: 172145, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569974

RESUMO

Copper (Cu) has sparked widespread global concern as one of the most hazardous metals to aquatic animals. Ocean acidification (OA) and warming (OW) are expected to alter copper's bioavailability based on pH and temperature-sensitive effects; research on their effects on copper on marine organisms is still in its infancy. Therefore, under representative concentration pathways (RCP) 2.6, 4.5, and 8.5, we used the multiple linear regression-water quality criteria (MLR-WQC) method to assess the effects of OA and OW on the ecological risk posed by copper in the Ocean of East China (OEC), which includes the Bohai Sea, Yellow Sea, and East China Sea. The results showed that there was a positive correlation between temperature and copper toxicity, while there was a negative correlation between pH and copper toxicity. The short-term water quality criteria (WQC) values were 1.53, 1.41, 1.30 and 1.13 µg·L-1, while the long-term WQC values were 0.58, 0.48, 0.40 and 0.29 µg·L-1 for 2020, 2099-RCP2.6, 2099-RCP4.5 and 2099-RCP8.5, respectively. Cu in the OEC poses a moderate ecological risk. Under the current copper exposure situation, strict intervention (RCP2.6) only increases the ecological risk of copper exposure by 20 %, and no intervention (RCP8.5) will increase the ecological risk of copper exposure by nearly double. The results indicate that intervention on carbon emissions can slow down the rate at which OA and OW worsen the damage copper poses to marine creatures. This study can provide valuable information for a comprehensive understanding of the combined impacts of climate change and copper on marine organisms.


Assuntos
Organismos Aquáticos , Cobre , Monitoramento Ambiental , Oceanos e Mares , Água do Mar , Poluentes Químicos da Água , Cobre/toxicidade , Água do Mar/química , Organismos Aquáticos/efeitos dos fármacos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Concentração de Íons de Hidrogênio , China , Mudança Climática , Aquecimento Global , Animais , Acidificação dos Oceanos
17.
Chemosphere ; 358: 142055, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641292

RESUMO

The impact of desalination brine on the marine environment is a global concern. Regarding this, salinity is generally accepted as the major environmental factor in desalination concentrate. However, recent studies have shown that the influence of organic contaminants in brine cannot be ignored. Therefore, a non-targeted screening method based on comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry (GC × GC-qMS) was developed for identifying organic contaminants in the desalination brine. A total of 404 compounds were tentatively identified from four seawater desalination plants (three reverse osmosis plants and one multiple effect distillation plant) in China. The identified compounds were prioritized based on their persistence, bioaccumulation, ecotoxicity, usage, and detection frequency. Twenty-one (21) compounds (seven phthalates, ten pesticides, four trihalomethanes) were then selected for further quantitative analysis and ecological risk assessment, including compounds from the priority list along with substances from the same chemical classes. Ecologically risky substances in brine include diisobutylphthalate and bis(2-Ethylhexyl) phthalate, atrazine and acetochlor, and bromoform. Most of the contaminants come from raw seawater, and no high risk contaminants introduced by the desalination process have been found except for disinfection by-products. In brine discharge management, people believed that all pollution in raw seawater was concentrated by desalination process. This study shows that not all pollutants are concentrated during the desalination process. In this study, the total concentration of pesticide in the brine increased by 58.42%. The concentration of ∑PAEs decreased by 13.65% in reverse osmosis desalination plants and increased by 10.96% in the multi-effect distillation plant. The concentration of trihalomethane increased significantly in the desalination concentrate. The change in the concentration of pollutants in the desalination concentrate was related to the pretreatment method and the chemical characteristics of the contaminants. The method and results given in this study hinted a new idea to identify and control the environmental impact factors of brine.


Assuntos
Salinidade , Água do Mar , Poluentes Químicos da Água , Purificação da Água , Água do Mar/química , Poluentes Químicos da Água/análise , Medição de Risco , Purificação da Água/métodos , China , Monitoramento Ambiental/métodos , Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas , Sais/química , Ácidos Ftálicos/análise , Trialometanos/análise
18.
Mar Pollut Bull ; 202: 116378, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38678731

RESUMO

Based on the monitoring data of 137Cs and 90Sr in Tian Bay in 2005-2023, the impacts of the operation of Tianwan Nuclear Power Plant on the marine ecosystem were assessed. The 137Cs and 90Sr activity concentrations in the seawater and sediment varied within the background ranges. The radiation dose rates derived from 137Cs and 90Sr for the marine organisms ranged from 2.4 × 10-5 to 2.2 × 10-4 nGy/h, it was far below the most conservative screening dose rate (10 µGy/h). The committed effective dose for humans was 0.070-0.094 µSv, 1/1500th of the world's mean annual effective dose (0.12 mSv) from ingesting food containing uranium and thorium series nuclides. Radiation risk assessment showed no radiation risk for the long-term discharge of nuclear wastes in the future. Overall, the long-term normal operation of TNPPs has almost no radiation impact on the adjacent marine ecosystem.


Assuntos
Organismos Aquáticos , Radioisótopos de Césio , Ecossistema , Centrais Nucleares , Monitoramento de Radiação , Água do Mar , Poluentes Radioativos da Água , Poluentes Radioativos da Água/análise , Radioisótopos de Césio/análise , Água do Mar/química , China , Sedimentos Geológicos/química , Medição de Risco
19.
Mar Pollut Bull ; 202: 116362, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615517

RESUMO

In the current study, an environmental assessment of surface seawater in Tangier Bay was conducted by analyzing physicochemical parameters and trace elements, such as As, Cr, Zn, Cd, Pb, and Cu. The results showed mean concentrations (µg/l) of 22.50 for As, 0.46 for Cr, 8.57 for Zn, 15.41 for Cd, 0.23 for Pb, and 1.83 for Cu. While most trace elements met the guidelines, elevated levels of Cd raised concerns about long-term exposure. Pollution indices, including the contamination factor, degree of contamination, and water quality index, indicate the impact of human activities, dividing sites into arsenic-cadmium contamination, wastewater influence, and low pollution levels. Statistical methods, such as ANOVA, revealed no significant differences in trace element levels across the bay. PCA and HCA revealed that Cr, Cu, and Zn originated from common anthropogenic sources, whereas Pb and Cd originated from distinct sources. As indicates that natural geological processes influence its origin.


Assuntos
Baías , Monitoramento Ambiental , Água do Mar , Oligoelementos , Poluentes Químicos da Água , Oligoelementos/análise , Poluentes Químicos da Água/análise , Água do Mar/química , Mar Mediterrâneo , Medição de Risco , Humanos , Metais Pesados/análise , Arsênio/análise
20.
Environ Sci Technol ; 58(14): 6181-6191, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38536729

RESUMO

Flow-electrode capacitive deionization (FCDI) is a promising technology for sustainable water treatment. However, studies on the process have thus far been limited to lab-scale conditions and select fields of application. Such limitation is induced by several shortcomings, one of which is the absence of a comprehensive process model that accurately predicts the operational performance and the energy consumption of FCDI. In this study, a simulation model is newly proposed with initial validation based on experimental data and is then utilized to elucidate the performance and the specific energy consumption (SEC) of FCDI under multiple source water conditions ranging from near-groundwater to high salinity brine. Further, simulated pilot-scale FCDI system was compared with actual brackish water reverse osmosis (BWRO) and seawater reverse osmosis (SWRO) plant data with regard to SEC to determine the feasibility of FCDI as an alternative to the conventional membrane processes. Analysis showed that FCDI is competent for operation against brackish water solutions under all possible operational conditions with respect to the BWRO. Moreover, its distinction can be extended to the SWRO for seawater conditions through optimization of its total effective membrane area via scale-up. Accordingly, future directions for the advancement of FCDI was suggested to ultimately prompt the commercialization of the FCDI process.


Assuntos
Cloreto de Sódio , Purificação da Água , Filtração , Eletrodos , Água do Mar
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