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1.
Bull Environ Contam Toxicol ; 105(4): 546-552, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32870331

RESUMO

The heavy metals were studied in water, sediments, algae, and various tissues of Glyptosternon reticulatum and Cyprinus carpio from River Swat, Pakistan, using flame atomic absorption spectrophotometer. The Zn, Cu, Pb and Ni were higher in water at sewage site compared to upstream and downstream sites. In sediments, the Ni and Cd were not detected whereas Cu, Pb and Zn were higher at downstream followed by sewage and upstream sites. The Ni and Zn in algae were higher at upstream and sewage sites compared to downstream site whereas Pb and Cd were higher at upstream site compared to sewage and downstream sites and Cu was found same at all the three sites. The heavy metals (Zn > Cu > Pb and Ni) in tissues (liver > gills > skin > muscles) of G. reticulatum was higher than in C. carpio. This study recommends the proper monitoring of River Swat in order to save its water and inhabitant aquatic life.


Assuntos
Carpas/metabolismo , Peixes-Gato/metabolismo , Sedimentos Geológicos/análise , Metais Pesados/metabolismo , Rios/química , Spirogyra/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Metais Pesados/análise , Paquistão , Especificidade da Espécie , Distribuição Tecidual , Poluentes Químicos da Água/análise
2.
Bull Environ Contam Toxicol ; 105(4): 538-545, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32968836

RESUMO

In the present study, heavy metals (Cd, Cu, Pb, and Zn) level in the water, sediment, and crabs were analyzed from Noyyal and Chinnar Rivers of the Western Ghats in Tamil Nadu, India. Based on our results, Noyyal River is considered as polluted environment due to the discharge of contaminants by various anthropogenic activities, whereas, Chinnar River maintained as unpolluted one due to its tributary nature of Noyyal River located in Western Ghats hills. The results showed that the heavy metals in water and sediments were higher in Noyyal River. Also, the level of bioaccumulation of studied metals and biochemical constituents were higher in the crab Spiralothelphusa hydrodroma sampled from Noyyal River than Barytelphusa cunicularis collected from Chinnar River. The present findings revealed that the crab sampled from Noyyal River had elevated heavy metals which lead to a significant increase in biochemical constituents to overcome the stress.


Assuntos
Braquiúros/metabolismo , Exposição Ambiental , Sedimentos Geológicos/análise , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Bioacumulação , Monitoramento Ambiental , Feminino , Índia , Masculino , Rios/química , Especificidade da Espécie , Inquéritos e Questionários , Poluição Química da Água
3.
PLoS One ; 15(9): e0238349, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32898181

RESUMO

Nowadays, citizen science has become increasingly popular, especially in Western countries. In Hong Kong, citizen science projects are mostly used for public education, while utilizing citizen scientists in published scientific research is very rare. On the other hand, with the increasing threats to global water security, Hong Kong requires new adaptation and strategy in facing the impairment of local freshwater systems. However, unfortunately, the number of full-scale urban river research appears to be declining. In this regard, citizen science can offer an alternative option as one of the new integrated water management strategies in Hong Kong. In this study, the water quality of seven rivers and streams in Hong Kong was studied monthly for two years by a group of citizen scientists. The main goal is to examine the reliability of data collected by citizen scientists by comparing it with the official data from the Environmental Protection Department of Hong Kong (EPD). Results show that the water temperature and conductivity data acquired by the citizen scientists were highly comparable to the official data. Also, moderate to strong correlations in water pH, turbidity, and dissolved oxygen levels were found between citizen scientists and official data. Since the citizen science data remained as high as 70% of relevance to the official data, we believe that this may serve as a supplement to the lacking official or professional water quality monitoring data in Hong Kong. Even though the use of volunteer data in water quality monitoring unavoidably exists with errors and bias, this study demonstrates a successful outcome of utilizing citizen science programme in urban river monitoring in Hong Kong.


Assuntos
Ciência do Cidadão/métodos , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Melhoria de Qualidade , Rios/química , Qualidade da Água/normas , Participação da Comunidade , Hong Kong , Humanos
4.
Bull Environ Contam Toxicol ; 105(4): 626-632, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32959072

RESUMO

The paper presents results of the research on the dynamics of changes in the concentration of mercury in surface waters. The importance of mercury as an environmental pollutant results from specific properties of this metal, many sources of contamination, volatility, mobility, stability and high toxicity of its specific chemical forms. Samples of surface water collected from three rivers: the Bug, the Liwiec and the Muchawka were analysed. The Muchawka River flows into the Liwiec River, which in turn is a tributary of the Bug River. The technique of isotachophoresis was employed, using a solution of a biodegradable and environmentally non-toxic derivative of electrostatically stabilised silanates as the terminating electrolyte. The highest average mercury concentration of 0.89 µg/dm3 was determined in water samples collected from the Bug River in January, whereas the lowest concentration of 0.42 µg/dm3 was recorded in water collected from the Muchawka River in September.


Assuntos
Monitoramento Ambiental , Mercúrio/análise , Poluentes Químicos da Água/análise , Eletrólitos/análise , Rios/química
5.
PLoS One ; 15(9): e0237716, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32886676

RESUMO

Bull trout (Salvelinus confluentus) are challenging to detect as a result of the species cryptic behavior and coloration, relatively low densities in complex habitats, and affinity for cold, high clarity, low conductivity waters. Bull trout are also closely associated with the stream bed, frequently conceal in substrate, and this concealment behavior is poorly understood. Consequently, population assessments are problematic and biologists and managers often lack quantitative information to accurately describe bull trout distributions, estimate abundance, and assess status and trends; particularly for stream-dwelling populations. During controlled laboratory trials, we recorded concealment, resting, and swimming behavior of juvenile wild bull trout in response to: (1) constant and fluctuating water temperature, (2) presence or absence of light, and (3) substrate size. Light level had the strongest influence on wild fish concealment and more fish concealed as light levels increased from darkness to daylight. Wild fish were 14.5 times less likely to conceal in constant darkness and 4.1 times more likely to conceal in 12 h light x 12 h darkness compared to constant light. Wild fish were 6.2 times less likely to conceal in small (26-51 mm) substrate compared to larger (52-102 mm) substrate. As water temperature increased, fewer wild fish concealed. Knowledge of wild bull trout concealment will improve field sampling protocols and increase detection efficiencies. These data also enhance knowledge of bull trout niche requirements which illuminates ecological differences among species and informs conservation and restoration efforts.


Assuntos
Truta/fisiologia , Distribuição Animal , Animais , Comportamento Animal , Fotoperíodo , Rios/química , Natação , Temperatura
6.
Ecotoxicol Environ Saf ; 205: 111314, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956866

RESUMO

Brazilian freshwater ecosystems are continuously exposed to pesticides and domestic sewage. The Uruguay River was chosen for this study because of its international importance, as it flows through Brazil, Argentina, and Uruguay. It receives contaminants such as pesticides and domestic residues. Thus, the aim of this study to assess the accumulation of pesticides in muscle of the fish Astyanax jacuhiensis, its biochemical responses, and the presence of pesticides in water. In total, seven pesticides were registered in water from both river sites. Eight pesticides were detected in fish muscle. The biochemical responses showed that brain lipid peroxidation (LPO) and protein carbonyl (PC) in A. jacuhiensis were higher in the summer. Muscle showed the highest LPO levels in the spring and the highest PC in the summer. Liver LPO and PC levels were higher in the spring and summer. In the gills, the PC was higher in the spring and the LPO in the spring and winter. In the brain and in the gills, glutathione-S-transferase activity was high in the summer and autumn. Catalase activity was lower during the winter and spring. Non-protein thiol (NPSH) levels were lower in the brain in the winter and spring. Muscle tissue showed lower NPSH in the winter (site 1). Liver NPSH showed increased levels in liver in the spring and winter (site 2). The biochemical results clearly is related to pesticides and/or to the presence of other contaminants in the water such as metals or domestic sewage. The accumulation of pesticides in fish muscle added evidence that pesticides have been used in the area surrounding the Uruguay River. In conclusion, the biomarkers assayed in the present study could be used in future investigations considering other sampling sites along Uruguay River.


Assuntos
Characidae/fisiologia , Monitoramento Ambiental , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brasil , Characidae/metabolismo , Caraciformes/metabolismo , Caraciformes/fisiologia , Ecossistema , Brânquias/metabolismo , Peroxidação de Lipídeos , Metais/metabolismo , Praguicidas/análise , Rios/química , Estações do Ano , Poluentes Químicos da Água/análise
7.
Ecotoxicol Environ Saf ; 205: 111322, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32961494

RESUMO

Diatoms respond to toxicants in lotic systems, and they are commonly considered to be sensitive indicators in environmental safety assessment. In addition to the structural characteristics of the algal populations, recent studies have shown that endpoints such as nuclear anomalies or diatom motility measures can be affected quickly by environmental changes. We sought to determine if cell density, cell size, nuclear anomalies and motility of the diatom Nitzschia palea were useful indicators of sediment quality from agricultural streams. For this purpose, we exposed cultures of the diatom to elutriates from sediments of a stream that flows through an intensive agricultural area, and measured the responses of the populations for 7 days in laboratory tests. The bioassays showed that motility measures in Nitzschia palea and the condition of their nuclear membranes rapidly reflected the effects of sediment quality after only 48 h of exposure; mean cell density and length were affected by day 7. The sediment elutriates affected cell movements by shortening the total path length and decreasing cell velocity; they also increased the number of cells with nuclear membrane breakage. Our results from these bioassays show that diatom motility measurements and the condition of the nuclei might be indicators that respond faster to impacts than the traditional structural parameters, such as cell density, specific composition of the assemblage or diversity metrics of the algal communities more often used in biomonitoring.


Assuntos
Agricultura , Diatomáceas/fisiologia , Monitoramento Ambiental/métodos , Movimento Celular , Rios/química
8.
J Chromatogr A ; 1628: 461440, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822980

RESUMO

A selective and highly sensitive high performance liquid chromatography (HPLC) with fluorescence derivatization method was developed for determination of ethinyl estradiol (EE); one of endocrine-disrupting compounds (EDCs). The fluorescence derivatization procedure was based on Sonogashira coupling reaction using 4-(4, 5-diphenyl-1H-imidazole-2-yl) iodobenzene (DIB-I), a fluorescence labeling reagent, to derivatize EE in presence of copper and palladium ions. The formed fluorescent product was separated on Cosmosil 5C18 MS-II by an isocratic elution with a mobile phase composed of acetonitrile: 5.0 mM Tris-HNO3 buffer, pH 7.4 (60:40, v/v %). The detection wavelengths were set at 310 and 400 nm as excitation and emission wavelengths, respectively. Various parameters affecting derivatization reaction were optimized. Further, the proposed method was validated and a good linearity with low detection limit (S/N=3) 7.4 ng L-1 was obtained in water sample after a simple solid-phase disk extraction (C18 SPE disk) method. The proposed method was successfully applied for detection of EE in river water samples in order to monitor EE concentration and to distinguish its effect on the ecosystem and human health.


Assuntos
Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/métodos , Etinilestradiol/análise , Rios/química , Espectrometria de Fluorescência , Disruptores Endócrinos/análise , Fluorescência , Extração em Fase Sólida , Poluentes Químicos da Água/análise
9.
Ecotoxicol Environ Saf ; 204: 111093, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32805502

RESUMO

Phenolic Endocrine Disrupting Chemicals (EDCs) have drawn more and more interest due to their prevalence and persistence in aquatic environment. To study the adsorption of various phenolic EDCs on river sediments under natural conditions, we first sought to analyze the distribution characteristics of phenol and bisphenol A (BPA) in sediment from the Bahe River. The static adsorption experiments contained either single- or dual-contaminant of phenol and/or BPA in the system; they were conducted to characterize the adsorption of these two pollutants in the surface sediments and the main factors affecting the adsorption processes of the dual-contaminant system, including particle size, humic acid (HA) concentration, pH, and temperature. Results showed that in certain seasons, there was a significant correlation between the levels of phenol and BPA in Bahe sediments. When comparing the adsorption behaviors of phenol and BPA on sediments in single- and dual-contaminant systems, we found that the phenol adsorption behavior varied, while that of BPA remained consistent across the different systems. Moreover, different effects were observed with regards to a single factor and the interaction of multiple factors on the adsorption of pollutants. Of the four single factors, only HA concentration had a significant effect on the phenol adsorption in sediment. When considering the interaction of multiple factors, the interaction between HA concentration and temperature significantly promoted the adsorption of phenol. The influence of factors on the adsorption of BPA was in the following order: particle size > HA concentration > pH > temperature. Particle size significantly inhibited BPA adsorption in the sediment, while the interaction between particle size and pH increased BPA adsorption.


Assuntos
Compostos Benzidrílicos/química , Fenol/química , Fenóis/química , Poluentes Químicos da Água/química , Adsorção , Disruptores Endócrinos/análise , Poluentes Ambientais , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Fenóis/análise , Rios/química , Temperatura , Poluentes Químicos da Água/análise
10.
Aquat Toxicol ; 227: 105604, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32846286

RESUMO

River sediment is the ultimate sink for heavy metal pollution. Copper (Cu) and zinc (Zn) are consistently found at environmentally significant levels in sediments worldwide. We hypothesized that the bioavailability and potential ecological risk of Cu and Zn in river sediments may be affected by seasonal variations and spatial distribution. In this study, we tested our hypothesis using highly industrialized river sediments (Laojie River) as an example. The concentration of heavy metals, pollution indexes, and risk indexes were evaluated and multivariate statistical analyses were performed. We found that seasonal variations affect heavy metal contamination, pollution indexes, and potential ecological risk in sediments and this effect was more severe in the dry season. In addition, higher levels of metal contamination, pollution indexes, and potential ecological risk were observed midstream and downstream of the Laojie River. We found that Cu and Zn were the primary contaminants in Laojie River sediments and may originate from common anthropogenic sources. Analysis of the chemical fractions further revealed that Cu and Zn exhibited high mobility and potential bioavailability risk. In addition, a high percentage and amount of Cu and Zn were found in exchangeable fractions, suggesting they pose a great risk to aquatic organisms. Our results indicate that seasonal variations and spatial distribution affect the bioavailability and potential ecological risk of Cu and Zn in river sediments. These findings suggest that seasonal variations and spatial distribution are important parameters to consider for environmental monitoring and environmental management in aquatic environments.


Assuntos
Cobre/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Zinco/análise , Disponibilidade Biológica , China , Poluição Ambiental/análise , Sedimentos Geológicos/química , Metais Pesados/análise , Medição de Risco , Rios/química , Estações do Ano , Poluentes Químicos da Água/toxicidade
11.
J Chromatogr A ; 1626: 461348, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797828

RESUMO

Solid-phase extraction (SPE) is a widely-used and very well-established sample preparation technique for liquid samples. An area of on-going focus for innovation in this field concerns the development of new and improved SPE sorbents that can enhance the sensitivity and/or the selectivity of SPE processes. In this context, mixed-mode ion-exchange sorbents have been developed and commercialised, thereby allowing enhanced capacity and selectivity to be offered by one single material. The ion-selectivity of these materials is such that either anion-exchange or cation-exchange is possible, however one limitation to their use is that more than one sorbent type is required to capture both anions and cations. In this paper, we disclose the design, synthesis and exploitation of a novel SPE sorbent based on microporous polymer microspheres with amphoteric character. We show that it is possible to switch the ion-exchange retention mechanism of the sorbent simply by changing the pH of the loading solution; anion-exchange dominates at low pH, cation-exchange dominates at high pH, and both mechanisms can contribute to retention when the polymer-bound amphoteric species, which are based on the α-amino acid sarcosine (N-methylglycine), are in a zwitterionic state. This is an interesting and useful feature, since it allows distinctly different groups of analytes (acids and bases) to be fractionated using one single amphoteric sorbent with dual-functionality. The sarcosine-based sorbent was applied to the SPE of acidic, basic and amphoteric analytes from ultrapure water, river water and effluent wastewater samples. Under optimised conditions (loading 100 mL of sample at pH 6, washing with 1 mL of MeOH and eluting with an acidic or basic additive in MeOH) the recoveries for most of the compounds were from 57% to 87% for river water and from 61% to 88% for effluent wastewater. We anticipate that these results will lay the basis for the development of a new family of multifunctional sorbents, where two or more separation mechanisms can be embedded within one single, bespoke material optimised for application to challenging chemical separations to give significant selectivity advantages over essentially all other state-of-the-art SPE sorbents.


Assuntos
Ácidos/química , Microesferas , Polímeros/química , Extração em Fase Sólida/métodos , Adsorção , Cátions , Concentração de Íons de Hidrogênio , Troca Iônica , Porosidade , Rios/química , Solventes/química , Águas Residuárias/química , Poluentes Químicos da Água/análise
12.
J Chromatogr A ; 1626: 461359, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797838

RESUMO

The enantiomeric determination of chiral drugs in the environment is of emerging concern since their enantiomers often exhibit stereoselectivity in environmental occurrence, fate and toxicity. In this study a method based on solid-phase extraction followed by chiral liquid chromatography and high-resolution mass spectrometry has been developed for the enantiomeric determination of a group of cathinones in river water and effluent wastewater. The enantioseparation was carried out using a Chiralpak CBH column in reversed-phase mode, and optimised by evaluating the effects of flow rate, buffer concentration and organic modifier. Under optimal conditions, good enantioseparations (Rs ≥1.2) were achieved for all the analytes. Two mixed-mode cation-exchange sorbents (Oasis WCX and Oasis MCX) in solid-phase extraction were evaluated in river water. Oasis MCX sorbent showed better performance with apparent recoveries ranging from 57 to 91% and matrix effect ranging from -10 to 15%. It is worth noting that a shifting of retention times and loss of enantioresolutions in environmental water samples was observed for all the analytes when the Oasis WCX sorbent was used. The method was validated with river water and effluent wastewater samples and its overall performance was satisfactory. The method quantification limits for all the analyte enantiomers ranged from 1.0 to 2.9 ng/L in river water, and from 2.3 to 6.0 ng/L in effluent wastewater. The repeatability and reproducibility values, expressed as% relative standard deviation (n = 5) were less than 15%. The method was then applied to the analysis of river water and effluent wastewater. The racemic methylone and methedrone (EF=0.49 and 0.46, respectively) were detected at low ng/L in some of the river water samples.


Assuntos
Alcaloides/análise , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Alcaloides/química , Alcaloides/isolamento & purificação , Reprodutibilidade dos Testes , Rios/química , Extração em Fase Sólida/métodos , Estereoisomerismo , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
13.
J Chromatogr A ; 1626: 461364, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797843

RESUMO

A new type of restricted access media-imprinted nanomaterials (RAM-MIPs) were successfully prepared on the surface of metal-organic framework by reversible addition fragmentation chain transfer polymerization technology. Then it was applied as a dispersed solid phase extraction (DSPE) material in analysis of fluoroquinolones (ofloxacin, pefloxacin, norfloxacin, enrofloxacin and gatifloxacin) in untreated milk and river water by HPLC-UV detection. The resulted material has a good binding amounts (60.81 mg g-1), rapid binding kinetic (15 min) and satisfactory selectivity as well as has a good ability to eliminate matrix interference. Several major factors affecting DSPE efficiency, pH of sample solution, dosage of RAM-MIPs, adsorption time and volume ratios of elution solvent were primarily optimized. In optimization conditions, RAM-MIPs-DSPE was combined with HPLC-UV to enrich fluoroquinolones in untreated milk and river water, achieving satisfactory linear correlation (R2 > 0.9988), good limits of detection (LOD, 1.02-3.15 µg L-1 for milk and 0.93-2.87 µg L-1 for river water) and better recoveries (80.7-103.5% and 85.1-105.9% with relative standard deviation (RSD) of not higher than 5.3% and 4.7% for milk and river water samples, respectively). The research results illustrate that it provides a simple and efficient method for the direct detection of FQs in complex samples.


Assuntos
Antibacterianos/análise , Fluoroquinolonas/análise , Estruturas Metalorgânicas/química , Leite/química , Nanoestruturas/química , Rios/química , Extração em Fase Sólida/métodos , Adsorção , Animais , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Fluoroquinolonas/isolamento & purificação , Impressão Molecular , Polimerização
14.
Ecotoxicol Environ Saf ; 202: 110938, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800221

RESUMO

The religious mass gathering and bathing can pose a multitude of significant public health challenges and lead to severe alterations in the river microbial ecology. The Pandharpur Wari is an annual pilgrimage of Maharashtra, India, where millions of devotees carry the footprints of the saint-poets and pay their obeisance to Lord Vitthal on the 11th day of moon's waxing phase (Ashadi Ekadashi). As a part of the ritual, the engrossed devotees, walk over 250 km, take a first holy dip in a sacred river Indrayani at Alandi and secondly in Bhima River at Pandharpur. The MinION-based shotgun metagenomic approach was employed to examine the impact of spiritual mass bathing on environmental changes (concerning the river microbial community structure and functions); and public health aspects (in terms of changes in the pathogenic potential and antibiotic resistance). The analysis of bathing and post-bathing samples of both the rivers revealed alterations in the alpha and beta diversity, indicating significant spatiotemporal variations in the overall microbial structure and function. Furthermore, the analysis revealed up to 80% of differences in the abundance of virulence genes between the bathing and post bathing samples. We observed parallel increase of priority skin and enteric pathogens (ranging from 11% to 80%) such as Acinetobacter baumannii, Staphylococcus aureus, Streptococcus pyogenes, Mycobacterium tuberculosis, and Pseudomonas aeruginosa during the bathing event. Moreover, we observed a significant increase in the antibiotic resistance in the bathing samples of Bhima and Indrayani rivers respectively. Altogether, this is the first comprehensive metagenomic study unravelling the influence of religious mass-bathing on the riverine ecosystem.


Assuntos
Monitoramento Ambiental , Rios/química , Poluição da Água/estatística & dados numéricos , Resistência Microbiana a Medicamentos , Ecossistema , Humanos , Índia , Metagenoma , Microbiota , Qualidade da Água
15.
Ecotoxicol Environ Saf ; 202: 110976, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800235

RESUMO

In this study, we first reviewed the current research progress regarding the presence of environmental microplastics (MPs) in environment in China from 2010 to 2019. Results showed that: (1) current research has primarily focused on river and marine environments rather than soils and dusts, mainly located in eastern China, i.e., the Yangtze river, Poyang lake, Dongting lake, Yellow sea, and Bohai sea; (2) the abundance of MPs found in water bodies (sediments) of the rivers in China ranged from 3.9 to 7900 items·m-3 (19.0 × 103-13600.5 × 103 items·km-2), and 20-24300 items·kg-2 (170-5500 × 106 items·km-2) in the sediments, respectively; in lake water the range was 340-8900 items·m-3 (5 × 103-340 × 105 items·km-2) and 8 to 1200 items·m-2/25-300 items·kg-1 in the sediments, respectively; in marine water the range was 0.003-540 items·m-3 (0-380,100 item·km-2) and 1.3-14700 item·kg-1 in the sediments, respectively; in fish, shellfish, and natural planktons from ocean and freshwater, the range was 0-57 items·individuals-1 (0-168 items·g-1); (3) The absorption and toxicological effects of MPs in freshwater and oceans have mainly focused on polyethylene (PE), polypropylene (PP), and polystyrene (PS); (4) the sources of microplastics in soils and dusts primarily come from urban/town activities; for rivers and lakes (estuary), they primarily come from urban activities; for coastal waters, fishing gear and nets, and the maritime activities were the main sources.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Microplásticos/análise , Rios/química , Solo/química , Poluentes Químicos da Água/análise , China , Cidades , Poeira/análise , Estuários , Oceanos e Mares , Polietileno/análise , Polipropilenos/análise , Poliestirenos/análise
16.
J Chromatogr A ; 1628: 461437, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822977

RESUMO

During stoppers production, large amounts of cork by-products (CBPs) are generated, being used as low-value material. This project aims to turn CBPs into smart, natural and sustainable materials (sorbent) for solid-phase extraction (SPE) of pesticides from water. The study describes the use of CBPs for the extraction of 17 fungicides (metalaxyl, cyprodinil, tolylfluanid, procymidone, folpet, fludioxonil, myclobutanil, kresoxim methyl, iprovalicarb, benalaxyl, trifloxystrobin, fenhexamid, tebuconazole, iprodione, pyraclostrobin, azoxystrobin and dimethomorph) followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis. The most critical parameters affecting SPE were optimized by experimental design methodology. Under the optimal conditions, the method was successfully validated in terms of linearity, repeatability, and intermediate precision. Fungicide recovery was assessed in different real water samples including river, fountain, rainwater and spring water at 3 concentration levels (0.1, 0.5 and 10 µg L-1). Recoveries ranged between 70-118% with RSD values lower than 20%, and matrix effects were not observed. Finally, the method was applied to samples from irrigation, rain, and river water, all collected in vineyards areas, revealing the presence of 10 of the 17 fungicides, at concentration up to hundreds of µg L-1. The use of CBPs seems to be a promising low-cost and ecofriendly alternative to be employed as sorbent in SPE techniques to extract fungicides from the aquatic environment.


Assuntos
Fungicidas Industriais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Adsorção , Análise de Variância , Tamanho da Partícula , Chuva , Rios/química , Espectrometria de Massas em Tandem/métodos , Água/química
17.
Ecotoxicol Environ Saf ; 204: 111065, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32784014

RESUMO

In the present study, chemical analysis of contaminants (three classes of organic pollutants and seven metals) and elutriate toxicity test were adopted to evaluate the potential environmental hazards of dredged sediment samples from five sites (SS1-5) along Huangpu River Channel (Shanghai Harbor, China). The metal Pb, Cu, Cr, Zn and the organic pollutants including total hexachlorocyclohexane (HCHs) and total dichlorodiphenyltrichloroethane (DDTs) in the five samples exceeded the threshold for effects level (TEL) to varying degrees. The probable effect concentration quotients (QPECm) of contaminants from the five dredged samples were all above 0.25, which means potential toxicity risks. Elutriate toxicity tests using medaka fish (Oryzias melastigma) and manila clam (Ruditapes philippinarum) showed that SS2 caused mortality to both species and SS1 caused mortality to fish. To explore the molecular biomarkers that may reflect the toxic effects, differential expressed genes were identified by RNA-Seq-based transcriptome profiling from the survived clams exposed to the two polluted elutriates (SS1, SS2). In clams exposed to SS1 and SS2 elutriate, 368 and 860 differential expressed genes (DEGs) were up-regulated, 199 and 1304 genes were down-regulated, respectively. Fourteen DEGs were selected from the enriched pathways that reflect cytotoxicity and responses to xenobiotics for the following quantitative real time PCR analysis. The transcriptomic profiling and the selected gene's expression patterns from clams exposed to SS1 and SS2 showed significant differences with the non-contaminated and control groups. Using the expression data of the selected gene battery in Factor Analysis allowed the discrimination between contaminated and non-contaminated sites and may reflect an influence gradient of sites. The development of the assay of these molecular biomarkers may provide a rapid and high-throughput tool for the quality assessment of the dredging sediments.


Assuntos
Bivalves/efeitos dos fármacos , Monitoramento Ambiental/métodos , Expressão Gênica/efeitos dos fármacos , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/toxicidade , Animais , Bivalves/genética , China , DDT/toxicidade , Hexaclorocicloexano/toxicidade , Metais Pesados/toxicidade , Testes de Toxicidade
18.
Ecotoxicol Environ Saf ; 204: 110952, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32801032

RESUMO

Emerging contaminants such as synthetic musks and UV-filters as ingredients personal care products were widely used in human daily life in Thailand. The occurrence and fate of four synthetic musks and nine UV-filters were investigated in eight full-scale sewage treatment plants (STPs) and their receiving aquatic environments in Bangkok and Pattaya, Thailand. All target compounds were detected in every single sample from STPs and surface water with magnitude from ng/L to µg/L. HHCB-lactone and HMS were found as the predominant musk and UV filter in influent and effluent of STPs, respectively. HHCB-lactone was also found with the highest concentration up to 79501 ng/g (dw) in the sludge. Low removal efficiency range from -37% (HHCB-lactone) to 58% (AHTN) were found for four musks in the STPs. The total emission of Σ4musks and Σ9UV-filters were estimated to be up to 16.7 mg/person/day and 0.28 mg/person/day by the STPs. Three synthetic musks and seven UV-filters were detected in fish from the receiving river. Concentration and emission of musks and UV filters found in this study from Thailand were much higher than those reported in many other countries worldwide. The preliminary ecological risk assessment showed that Musk xylene, 4-MBC and OC may pose high risk to aquatic organisms in the riverine and estuarine environment in Thailand.


Assuntos
Monitoramento Ambiental , Rios/química , Água do Mar/química , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Cidades , Tailândia
19.
Ecotoxicol Environ Saf ; 205: 111113, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32836153

RESUMO

Eutrophication is a global problem, and bacterial diversity and community composition are usually affected by eutrophication. However, limited information on the ecological significance of bacterial community during algae blooms of rivers has been given, more studies should be focused on the bacterial diversity and distribution characteristics in eutrophic rivers. In this study, we explored the spatial variations of bacterial biomass, community structure, and their relationship with environmental factors in the eutrophic Xiangxi River. The content of Chlorophyll (Chl) was about 16 mg/L in the midstream (S2, S3), which was in the range of light eutrophication. Significant spatial variation of bacterial community structure was found at different sites and depths (p < 0.05), and the driving environmental factor was found to be nitrogen, mainly detected as total nitrogen (TN), Kjeldahl nitrogen (KN), and ammonia nitrogen (NH4+) (p < 0.05). The midstream sites had some significantly different bacteria, including algicidal bacteria and dominant lineages during algal blooms. This result was consistent with the functional prediction, where significant higher abundance of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways was associated with algicidal substances in the midstream. At different water depths, some populations adapted to the surface layer, such as the class Flavobacteriia, and others preferred to inhabit in the bottom layer, such as Betaproteobacteria and Acidobacteria. The bacterial biomass was higher in the bottom layer than that in the surface and middle layer, and temperature and pH were found to be the major driving factors. The bacterial diversity increased with the increasing of depths in most sampling sites according to operational taxonomic units (OTUs), Chao1 and ACE indexes, and PO43- was demonstrated to be the most significant factor. In summary, this study offered the evidence for microbial distribution characteristics across different sites and depths in summer, and its relationship with environmental variables in a eutrophic river.


Assuntos
Monitoramento Ambiental/métodos , Eutrofização , Microbiota , Proteobactérias/crescimento & desenvolvimento , Rios , Biomassa , China , Clorofila/análise , Microbiota/genética , Nitrogênio/análise , Fosfatos/análise , Fósforo/análise , Proteobactérias/classificação , Proteobactérias/genética , RNA Ribossômico 16S/genética , Rios/química , Rios/microbiologia , Estações do Ano , Temperatura
20.
PLoS One ; 15(8): e0236410, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797095

RESUMO

The use and management of single use plastics is a major area of concern for the public, regulatory and business worlds. Focusing on the most commonly occurring consumer plastic items present in European freshwater environments, we identified and evaluated consumer-based actions with respect to their direct or indirect potential to reduce macroplastic pollution in freshwater environments. As the main end users of these items, concerned consumers are faced with a bewildering array of choices to reduce their plastics footprint, notably through recycling or using reusable items. Using a Multi-Criteria Decision Analysis approach, we explored the effectiveness of 27 plastic reduction actions with respect to their feasibility, economic impacts, environmental impacts, unintended social/environmental impacts, potential scale of change and evidence of impact. The top ranked consumer-based actions were identified as: using wooden or reusable cutlery; switching to reusable water bottles; using wooden or reusable stirrers; using plastic free cotton-buds; and using refill detergent/ shampoo bottles. We examined the feasibility of top-ranked actions using a SWOT analysis (Strengths, Weaknesses, Opportunities and Threats) to explore the complexities inherent in their implementation for consumers, businesses, and government to reduce the presence of plastic in the environment.


Assuntos
Monitoramento Ambiental , Plásticos/toxicidade , Rios/química , Poluentes Químicos da Água/toxicidade , Comportamento do Consumidor , Técnicas de Apoio para a Decisão , Poluição Ambiental , Humanos , Plásticos/química , Reciclagem , Resíduos/análise , Poluentes Químicos da Água/química
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