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1.
J Chromatogr A ; 1626: 461346, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797826

RESUMO

A molecularly imprinted polymer was synthesized and characterized to be used as solid-phase extraction sorbent for simultaneous chlorpyrifos and diazinon and their oxon derivatives. Several imprinted polymers were prepared and evaluated in a retention study of these analytes compared with a non-printed polymer. Several parameters affecting the extraction of imprinted polymer such as washing solvent, composition and volume of the eluting solvent and sample volume, were also investigated. Under the optimum conditions, the developed method provided satisfactory limits of detection ranging between 0.07 µg L-1 to 0.12 µg L-1 and the material showed an excellent reusability (> 50 reuses). The method was applied to the extraction and preconcentration of these analytes in water samples. The average recoveries ranged from 79 ± 6 to 104 ± 3 %.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Impressão Molecular , Praguicidas/análise , Clorpirifos/análise , Clorpirifos/isolamento & purificação , Diazinon/análise , Diazinon/isolamento & purificação , Água Doce/análise , Limite de Detecção , Praguicidas/isolamento & purificação , Polímeros/química , Extração em Fase Sólida , Espectrofotometria Ultravioleta
2.
J Chromatogr A ; 1626: 461324, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797817

RESUMO

Sorption of PFASs onto surfaces of laboratory materials has been frequently reported. Due to the often complex and poorly understood nature of such sorption, workarounds have often included use of whole samples only, accompanied by sample vessel rinsing to desorb active surfaces. The resulting methods tend to require considerable sample preparation times and preclude typical activities such as aliquoting and dilution of water samples prior to extraction. This manuscript reports an approach for PFAS analysis which uses subsampling of water matrices from vessels including centrifuge tubes and autosampler vials, through the optimized use of solvent to reduce PFAS retention on subsampling vessels. Online solid phase extraction (SPE) using a weak anion exchange resin is then used to concentrate sample aliquots to improve sensitivity and allow for removal of matrix interferences. With the technique of ultra performance liquid chromatography (UPLC) coupled to isotope dilution tandem mass spectrometry, statistically based quantitation limits ranged from sub ng/L to single digit ng/L for carboxylate, sulfonate, and sulfonamide PFASs analytes from C4 to C12. Linear calibration ranges were from 0.25 to 4000 ng/L. Matrix effects relevant for drinking water treatment studies, such as cations, organic carbon, and competing PFAS compounds, were evaluated and found to not impact method performance within QC criteria consistent with study data quality objectives.


Assuntos
Fluorcarbonetos/análise , Indicadores e Reagentes/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão , Fluorcarbonetos/isolamento & purificação , Água Doce/análise , Indicadores e Reagentes/isolamento & purificação , Marcação por Isótopo , Sais/química , Extração em Fase Sólida , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
3.
J Chromatogr A ; 1626: 461386, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797858

RESUMO

In this study, the microcrystalline cellulose/metal-organic framework 199 hybrid (MCC/MOF-199) was applied as sorbent for the dispersive micro-solid phase-extraction (D-µSPE) of chlorophenols. The D-µSPE method combined with high-performance liquid chromatography- ultraviolet detection (HPLC-UV) was employed to determine of four chlorophenols including 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2,3-dichlorophenol (2,3-DCP), and 2,5-dichlorophenol (2,5-DCP) in aqueous. The main parameters of the D-µSPE process that influence the extraction (i.e. the amount of sorbent, elution condition, extraction time, and pH) were investigated and optimized. Based on the outputs, the presence of MCC on the surface of MOF-199 leads to improve the properties of MOF-199 and the MCC/MOF-199 has the highest sorption capacity, durability, and porosity in comparison with MCC and MOF-199. According to the validation study at the optimized conditions, the linearity for the analytes was achieved in the range from 0.1 to 200 ng mL-1 for 2-CP and 4-CP and 0.15 to 200 ng mL-1 for 2,3-DCP and 2,5-DCP with correlation coefficients between 0.9928 and 0.9965. The limits of detection calculated at S/N=3 were in the range of 0.03-0.05 ng mL-1. Besides, the relative standard deviations (RSDs) for three spiking levels (0.2, 10,100 ng mL-1) do not exceed 6.8% and extraction recoveries are between 81.0% and 88.3%. Finally, the D-µSPE-HPLC-UV method was successfully applied to the analysis of CPs in real water samples (mineral, river and wastewater samples) with good recoveries (95.8 to 99.5%) and satisfactory precisions (RSD < 6.8%).


Assuntos
Celulose/química , Clorofenóis/análise , Estruturas Metalorgânicas/química , Microextração em Fase Sólida/métodos , Clorofenóis/química , Clorofenóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Água Doce/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Rios/química , Espectrofotometria Ultravioleta , Águas Residuárias/análise
4.
Environ Pollut ; 265(Pt B): 115038, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32599325

RESUMO

Organic pollution of urban rivers caused by stormwater discharge is a global problem. Traditional bioremediation of organic matters (OM) by aerobes could be restrained in anaerobic environments, which usually occurr in polluted river sediments. In this study, an anaerobic remediation technology has been developed to enhance the in-situ removal of organic matters in river sediments, humic-reducing sludge (HRS) was adapted from traditional activated sludge; it exhibited a strong humic-reducing ability. Nitrate and biostimulants were used to stimulate HRS. The change of microbial community between AQDS-adapted and non-AQDS-adapted was analyzed, and the effect of HRS augmentation and Nitrate/biostimulant addition on TOM removal were discussed from the perspective of light and heavy fraction organic matters (LFOM and HFOM). The results have indicated that, after adaptation, HRS had increased the bacterial population of Anaerolineales and Desulfuromonadales, which was related to the carbon metabolism and electron-transfer ability. On the other hand, the adaptation decreased the population of bacteria related to the sulfur/sulfate circulation. This characteristic of the HRS was potentially benificial to reducing the occurrence of black-odor phenomenon. Also, the removal efficiency of TOM in sediment was significantly improved by using HRS because HRS could facilitate the removal of HFOM. Fourier Transform Infrared Spectroscopy (FTIR) analysis indicated that the advantage of decomposing HFOM using HRS resulted from the fact that the HFOM contained redox mediators to facilitate humic-reducing respiration. In addition, nitrate appeared to be crucial for the enhancement of HRS in sediments. These findings have allowed for the development of a technology for in-situ anaerobic remediation of urban river sediments. They could also help to understand humic-reducing mechanism in the sediment during anaerobic bioremediation.


Assuntos
Sedimentos Geológicos , Esgotos , Biodegradação Ambiental , Água Doce/análise , Rios
5.
PLoS One ; 15(6): e0234853, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555679

RESUMO

A new method to evaluate archaeological wetland sites in a more objective way was tested. Different wetland environments have been sampled in areas of a nature reserve and their macroremain content analysed to build a modern analogue dataset. This dataset was then used to characterise archaeological samples from a navigation channel from the Roman port city Lattara. In the modern analogue samples, the different wetland types (saline/brackish or fresh water) could be differentiated in the correspondence analysis. Within these groups, the sampled area of the littoral (submerged, shoreline, unsubmerged) could also be differentiated. This dataset can therefore provide a basis for the interpretation of the nature and degree of aquatic influence and layer formation processes in archaeobotanical records of coastal sites. In the tested archaeological samples from the navigation channel of Lattara, changes in space and time could be tracked using the modern analogue dataset and geoarchaeological information. The channel lost its fresh water supply and silted up over a short period of time (approx. 100 years).


Assuntos
Água Doce/análise , Sedimentos Geológicos/análise , Plantas , Águas Salinas/análise , Áreas Alagadas , Arqueologia , Conjuntos de Dados como Assunto , França , Mar Mediterrâneo
6.
Ecotoxicol Environ Saf ; 201: 110821, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32544746

RESUMO

Primary production (PP) is a key variable to evaluate the quality of the ecological services provided by freshwater bodies because it gives information on the amount of oxygen and organic matter incorporated into the system. We analysed the impact of a mixture of commercial formulations of glyphosate- and 2,4-D-based herbicides (Roundup Max® and AsiMax 50®, respectively) on freshwater primary production. Primary production was studied through the oxygen exchange method. Four measurements were made during a 23-day experiment in outdoor mesocosms using the light and dark bottle method. High and low concentrations of the active ingredients were assayed to evaluate a concentration-dependent effect. Our results indicated that the mixture of Roundup Max® and AsiMax 50® acted mostly additively on gross and net primary production. Moreover, we found a concentration-dependent effect of each herbicide on PP. Thus, AsiMax 50® at low and Roundup Max® at high concentration induced a significant early decrease in respiration and gross primary production 4 h after application, attributable to physiological responses. Besides, significant increases in primary production were simultaneously recorded with increases in chlorophyll a concentration and micro + nano-phytoplankton abundance 7 days after the application of Roundup Max® at high concentration. This study contributes to the knowledge of the impact of widely used herbicides on freshwater ecosystems.


Assuntos
Água Doce/química , Herbicidas/toxicidade , Microbiota/efeitos dos fármacos , Fitoplâncton/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Ácido 2,4-Diclorofenoxiacético/análise , Ácido 2,4-Diclorofenoxiacético/toxicidade , Animais , Clorofila A/metabolismo , Relação Dose-Resposta a Droga , Água Doce/análise , Glicina/análogos & derivados , Glicina/análise , Glicina/toxicidade , Herbicidas/análise , Fitoplâncton/metabolismo , Poluentes Químicos da Água/análise
7.
Sci Total Environ ; 738: 139727, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32535285

RESUMO

The development of analytical methods for the detection and accurate quantification of algal toxins is of importance to assess the health risk of exposure to algal toxins in freshwater sources. This study established a sensitive and accurate analytical method for the quantification of 13 algal toxins (microcystins and nodularin) based on solid phase extraction (SPE) coupled with UPLC-MS/MS, in which 15N-microcystins were used as surrogate/internal standards. SPE method was optimized to extract the target algal toxins in freshwater samples. Good SPE efficiencies (84-96%) were achieved for the overwhelming majority of the investigated algal toxins when SPE was performed using HLB (500 mg, 6 mL) under alkaline conditions (pH 11). An accurate quantitative analysis of the algal toxins in real freshwater samples was performed by using 15N-labelled microcystins as isotopically labelled internal standards (ILISs), which compensated for the loss of target toxins during the whole analytical process. In addition, ILISs also helped to correct the effects of environmental matrices and instrument fluctuation in UPLC-MS/MS analysis. The limit of method quantification (MQL) for the algal toxins was <2.0 ng/L that is sensitive enough to quantify extremely low levels of target toxins in freshwater samples.


Assuntos
Microcistinas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Água Doce/análise
8.
Sci Total Environ ; 731: 139014, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32428751

RESUMO

Analytical methods based on direct injection (DI) and solid phase extraction (SPE) coupled with ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC- MS/MS) were developed for the determination of anatoxin-a (ATX-a), cylindrospermopsin (CYN), and homoanatoxin-a (HATX-a) in freshwater samples impacted with cyanobacterial blooms. The presence of CYN in freshwater samples was detected and quantified based on direct injection method, while ATX-a and HATX-a could be determined by both DI and SPE-based methods. Matrix effects (ME) on the signal intensity of the cyanotoxins were systematically evaluated for both direct injection and SPE extract samples. CYN, ATX-a, and HATX-a suffered a significant suppression during UPLC-MS/MS. The selection of internal standards (ISs) for compensating/correcting the losses of target cyanotoxins during sample preparation and matrix effects in UPLC-MS/MS analyses were systematically evaluated. Acetaminophen-d4 (an isotopically labelled acetaminophen) is a suitable internal standard for correcting the ME on the signal intensity of ATX-a and HATX-a, while the use of L-phenylalanine-d5 or caffeine-d9 as IS for correcting ME of these toxins was not efficient, as expected. The method detection limit (MDL) for the target cyanotoxins ranged from 0.6 to 15 ng/L, which is sensitive enough to detect the presence of these toxins in cyanobacterial bloom freshwater. The developed methods were successfully applied for routine monitoring of the occurrence of these cyanotoxins in a local water body. Monitoring results depicted that ATX-a, CYN and HATX-a were ubiquitously detected in water samples, at concentrations ranging from 70 to 24,600 ng/L.


Assuntos
Extração em Fase Sólida , Espectrometria de Massas em Tandem , Toxinas Bacterianas , Compostos Bicíclicos Heterocíclicos com Pontes , Cromatografia Líquida , Água Doce/análise , Microcistinas , Tropanos , Uracila/análogos & derivados
9.
Bull Environ Contam Toxicol ; 104(5): 689-700, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32303813

RESUMO

In this study, the hydrolysis of amisulbrom in buffer solutions and natural water samples were investigated. Effects of pH and temperature were tested in buffer solutions. Amisulbrom was stable in acidic and neutral aqueous solutions at 25°C, while quickly hydrolyzed with a half-life of 4.5 days (25°C) at pH 9.0. The kinetics rate equation was determined as k = 1.0234 × 1010 exp (-61.3760/R·T) (R2 = 0.9642) for hydrolysis of amisulbrom at pH 9.0. The pH, ionic strength, and solubility were important factors influencing the hydrolysis of amisulbrom in natural water samples. Furthermore, three hydrolysis products were separated and identified in buffer solution (pH 9.0) and natural water samples. A tentative transformation mechanism of amisulbrom was proposed to rationalize the formation of HPs (hydrolysis products) based on their structural identification, DFT (density functional theory), and hydrolysis profiles. Toxicity prediction using the quantitative structure-activity relationship model revealed that the HP-I, and HP-II were more toxic than the parent amisulbrom. This investigation was the first to evaluate the behavior of amisulbrom hydrolysis in aquatic systems.


Assuntos
Água Doce/química , Indóis/química , Modelos Químicos , Praguicidas/química , Triazóis/química , Poluentes Químicos da Água/química , Tampões (Química) , Água Doce/análise , Concentração de Íons de Hidrogênio , Hidrólise , Indóis/análise , Cinética , Modelos Moleculares , Estrutura Molecular , Concentração Osmolar , Praguicidas/análise , Solubilidade , Soluções , Temperatura , Triazóis/análise , Poluentes Químicos da Água/análise
10.
Food Chem ; 322: 126749, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283371

RESUMO

A simple method combining ultrasound assisted cloud point extraction (UA-CPE) and dispersive µ-solid phase extraction (D-µ-SPE) was developed for preconcentration of As, Cd, Cr, Co, Sb, Pb and Tl to inductively coupled plasma optical emission spectrometric (ICP-OES). At optimum conditions, the linearity, limits of detection and limits of quantification were 0.20-1000 µg L-1, 90-150 ng L-1 and 200-500 ng L-1, respectively. The intraday (n = 20) and intraday (n = 5) precisions reported as the relative standard deviation ranged from 1.5 to 3.5% and 1.9-4.5%. The trueness of the method was investigated using CRM BCR679, NIST SRM 1573a, and SRM 1640a, as well as spiked recovery experiments. Satisfactory recoveries and relative errors ranging from 97 to 99.3% and -4.0 to 2.4% were obtained. The proposed UA-CPE-D-µ-SPE/ICP-OES method was successfully applied for various real samples such as groundwater, bottled mineral water, river water and borehole water and food samples.


Assuntos
Água Doce/análise , Microextração em Fase Sólida/métodos , Espectrofotometria/métodos , Oligoelementos/análise , Verduras/química , Água Potável/análise , Limite de Detecção , Nanotubos de Carbono/química , Sonicação , Oligoelementos/isolamento & purificação , Verduras/metabolismo
11.
Food Chem ; 322: 126757, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283378

RESUMO

In the present work, for the first time, the filamentous fungus Fusarium sp. was utilized for devising a novel method for pre-concentration and determination of trace amounts of Pb(II), Cu(II), Cd(II), and Zn(II) ions, using a mini-column packed with Fusarium-coated multi-walled carbon nanotubes and inductively coupled plasma-optical emission spectrometry. Optimal analytical conditions including pH, ionic strength, elution solution, sample and eluent flow rates, and sample volume were determined. The detection limits were 0.39, 0.060, 0.021, and 0.025 ng mL-1 for Pb(II), Cu(II), Cd(II), and Zn(II) cations, respectively. This new method demonstrated a high performance for the analytes, and their adsorption was not affected by the different co-existing ions. The present procedure was validated by the analysis of standard reference materials, since the obtained data were in close agreement with reference values. Finally, this new procedure was successfully applied to analysis of heavy metal cations in natural food and water samples.


Assuntos
Fusarium/química , Metais Pesados/análise , Nanotubos de Carbono/química , Extração em Fase Sólida , Espectrofotometria/métodos , Adsorção , Cátions/química , Células Imobilizadas/química , Cobre/análise , Água Doce/análise , Concentração de Íons de Hidrogênio , Chumbo/análise , Chumbo/isolamento & purificação , Limite de Detecção , Metais Pesados/isolamento & purificação , Metais Pesados/normas , Concentração Osmolar , Padrões de Referência , Espectrofotometria/normas
12.
Environ Pollut ; 263(Pt B): 114367, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32276128

RESUMO

Research into the scope of litter pollution in freshwater systems has shown similar levels to the marine and coastal environment. Global model estimates of riverine emission rates of anthropogenic litter are largely based on microplastic studies as long-term and holistic observations of riverine macroplastics are still scarce. This study therefore aims to contribute a detailed assessment of macrolitter in the transitional waters of three major North Sea tributaries: Ems, Weser, and Elbe. Litter surveys were carried out in four river compartments: along the embankment, on the river surface, in the water column, and on the river bed. The data revealed spatio-temporal variability and distinct pollution levels for each compartment. Beaches had the highest debris diversity and were significantly more littered than vegetated sites and harbors. Stony embankments were least polluted. Benthic litter levels appeared substantial despite rapid burial of objects being likely due to high suspended sediment loads. Two extrapolation approaches were tested to scale daily and annual litter emission quantities of surface- and subsurface-floating litter. Using the mean (median) litter item mass from water column samples, total annual mass discharges were calculated: ∼0.9 (0.2) t y-1 to ∼2.8 (0.5) t y-1 emitted via the Ems, ∼1.3 (0.2) t y-1 to ∼12.0 (1.9) t y-1 through the Weser, and ∼14.7 (2.4) t y-1 to ∼801 (128) t y-1 carried into the North Sea by the Elbe. These rates deviate considerably from previous model estimates of plastic loads discharged by these three rivers. Future studies should therefore ground-truth model estimates with more river-specific and long-term field observations. Overall, the estimated plastic debris discharge quantities account for <1% of the total mass of mismanaged plastic waste per catchment.


Assuntos
Monitoramento Ambiental , Plásticos , Água Doce/análise , Mar do Norte , Rios , Resíduos/análise
13.
Food Chem ; 318: 126358, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32145541

RESUMO

Overdoses of SO2 and its derivatives (SO32-/HSO3-) in food or organisms are harmful to health. To detect SO32-/HSO3-, a novel NIR fluorescent probe 1, based upon the intramolecular charge transfer (ICT) mechanism, was developed. This probe was easily synthesized, and gave noticeable colorimetric and linear fluorescence changes at 690 nm after reaction with sulfite from 3.13 to 200 µM. Moreover, probe 1 displayed high sensitivity (LOD = 0.46 µM), excellent selectivity (among 13 kinds of anions and 3 kinds of biothiols) and quick response (within 30 min) towards SO32-/HSO3-. The SO32-/HSO3- sensing mechanism was confirmed as the Michael addition reaction. Furthermore, the probe showed wide applications for measuring SO32-/HSO3- in real samples, including sugar, tap water, wine and traditional Chinese medicine. The probe could also be used to detect SO32-/HSO3- in mitochondria of HepG2 cells and zebrafish, which suggested potential application for monitoring SO2 derivatives in clinical diagnostics.


Assuntos
Colorimetria/métodos , Corantes Fluorescentes/química , Mitocôndrias/química , Sulfitos/análise , Animais , Carboidratos , Medicamentos de Ervas Chinesas/análise , Água Doce/análise , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia de Fluorescência , Mitocôndrias/metabolismo , Imagem Óptica , Açúcares/análise , Vinho/análise , Peixe-Zebra/metabolismo
14.
Environ Geochem Health ; 42(9): 2865-2879, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32026272

RESUMO

To explore the sources and distribution characteristics of SO42- in the surface waters of the Linhuan mining area in Huaibei, river and surface water samples in subsidence and mine drainage locations in the study area were collected at different times. The conventional hydrochemical indexes and the eigenvalues of sulfur and oxygen isotopes were tested and analyzed. The results suggested the following: (1) The SO42- content showed seasonal changes: low-flow seasons > mid-flow seasons > high-flow seasons. (2) Based on δ34SSO4 and δ18OSO4 isotope analyses, the main source of SO42- was the dissolution of evaporite salt rocks in the stratum of the upstream area. The SO42- in the subsidence area was mainly from the river water supply, mine drainage and coal gangue leaching. The high concentration of SO42- in the mine drainage was mainly from the dissolution of evaporative salt rocks. (3) The calculation results of the ternary mixing model showed that the SO42- in the subsidence area water was affected by mine drainage and gangue leaching to different degrees. The results showed that the sulfate contribution proportion of the river water source to the subsidence area water was 35.8-65.9%; the sulfate contribution proportion of the mine drainage source to the subsidence area water was 2.0-26.6%; and the sulfate contribution proportion of the gangue leaching end source ranged from 16.3% to 56.9%. Coal mining activities had an important impact on the sulfate in the subsidence area water.


Assuntos
Minas de Carvão , Água Doce/química , Sulfatos/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental/métodos , Água Doce/análise , Isótopos de Oxigênio/análise , Rios/química , Estações do Ano , Isótopos de Enxofre/análise
15.
J Agric Food Chem ; 68(8): 2554-2561, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32027503

RESUMO

Excessive use of antibiotics in aquatic products is a serious problem for food safety and human health, and on-site detection of antibiotics is highly demanded. Herein, we proposed multivalence aptamer probes, allowing sensitive, label-free, and homogeneous detection of antibiotics in different aquatic products. Compared to commonly used aptamers, multivalence aptamer probes can provide multiple binding sites and a higher affinity for target molecules, and the iterative binding on different binding sites contributes to an amplified recognition effect, sharply increasing the response and sensitivity of aptamer probes. The 2-valence aptamer probes conferred a limit of detection of 0.097 nM for kanamycin detection, where it is estimated that their sensitivity is enhanced 12 times compared to 1-valence aptamer probes. Meanwhile, multivalence aptamer probes allowed us to specifically identify kanamycin among other antibiotics. It could detect kanamycin residual in aquatic products including river eel and puffer fish, as well as tap water with high precision. A multivalence design strategy of aptamer probes would significantly improve the detection performance of aptamers, facilitating the translation of aptamer for food safety control.


Assuntos
Antibacterianos/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Resíduos de Drogas/análise , Alimentos Marinhos/análise , Animais , Aptâmeros de Nucleotídeos/síntese química , Aquicultura , Técnicas Biossensoriais/instrumentação , Peixes/crescimento & desenvolvimento , Contaminação de Alimentos/análise , Água Doce/análise , Canamicina/análise , Limite de Detecção , Poluentes Químicos da Água/análise
16.
Aquat Toxicol ; 222: 105446, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32092595

RESUMO

The objective of this study was to examine the acute toxicity and sub-lethal effects of the commercial formulation of diquat dibromide, Reward® Landscape and Aquatic Herbicide, on multiple life stages of rainbow trout. The continuous exposure 96 h LC50 derived for juvenile feeding fry aged 85 d post-hatch was 9.8 mg/L. Rainbow trout eyed embryos and juvenile feeding fry were also exposed to concentrations of Reward® ranging from 0.12 to 10 mg/L during two 24 h pulse exposures separated by 14 d of rearing in fresh water to mimic the manufacturers instructions for direct applications to water bodies. Decreased survival and body morphometrics were evident at 9.3 mg/L during the embryo/alevin exposures, but not in feeding juveniles, indicating a higher sensitivity of the early life stage fish. Quantitative proteomics and subnetwork enrichment analyses were conducted in the livers for both life stages to evaluate protein profiles after exposure to 0.37 mg/L diquat via Reward® exposure. Unique protein profiles were revealed for pre-feeding swim-up fry and for feeding juvenile fish, reflecting differences between the two life stages in sub-cellular responses after diquat dibromide exposure. Hepatic proteome effects were more dramatic in the pre-feeding swim-up fry with 315 proteins differentially expressed between the control and exposed fish while in the later life stage feeding fry, only 84 proteins were different after Reward® exposure. Exposure to Reward® significantly increased RNA/mRNA processes, induced activation of Atk/mTOR and caspase activity, and altered energy homeostasis. Proteomic alterations are associated with reduced growth observed in embryo/alevin at higher exposure concentrations, offering insight into key events underlying growth impairment within the adverse outcome pathway framework. This study is the first to report the sub-cellular and whole organism level effects of diquat dibromide in a commercial formulation and demonstrates that concentrations based on aquatic application rates alter the hepatic proteome.


Assuntos
Diquat/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Herbicidas/toxicidade , Oncorhynchus mykiss/metabolismo , Proteoma/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Desenvolvimento Embrionário/efeitos dos fármacos , Água Doce/análise , Dose Letal Mediana , Fígado/efeitos dos fármacos , Fígado/embriologia , Fígado/metabolismo , Oncorhynchus mykiss/crescimento & desenvolvimento , Proteômica , Natação
17.
Nat Commun ; 11(1): 650, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005847

RESUMO

Inadequate water quality can mean that water is unsuitable for a variety of human uses, thus exacerbating freshwater scarcity. Previous large-scale water scarcity assessments mostly focused on the availability of sufficient freshwater quantity for providing supplies, but neglected the quality constraints on water usability. Here we report a comprehensive nationwide water scarcity assessment in China, which explicitly includes quality requirements for human water uses. We highlight the necessity of incorporating water scarcity assessment at multiple temporal and geographic scales. Our results show that inadequate water quality exacerbates China's water scarcity, which is unevenly distributed across the country. North China often suffers water scarcity throughout the year, whereas South China, despite sufficient quantities, experiences seasonal water scarcity due to inadequate quality. Over half of the population are affected by water scarcity, pointing to an urgent need for improving freshwater quantity and quality management to cope with water scarcity.


Assuntos
Água Doce/análise , Abastecimento de Água/normas , China , Humanos , Estações do Ano , Fatores Socioeconômicos , Poluição da Água , Qualidade da Água
18.
Isotopes Environ Health Stud ; 56(1): 36-50, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32067470

RESUMO

A scarce natural snow cover forces an increasing use of artificial snow on ski slopes and returns a small amount of snowmelt water available to plants outside the pistes at the beginning of the growing season. We tested if the use of artificial snow on the ski slopes and the decreased natural snow cover outside the ski slopes lead to changes in the leaf ecophysiology of dominant species in a ski area located in Northern Italy. Using carbon (13C/12C) and oxygen (18O/16O) stable isotope ratios in plant leaves, we estimated the intrinsic water use efficiency (iWUE) and we speculated about changes in photosynthesis and stomatal conductance. Furthermore, carbon and nitrogen concentration, pigments and dry matter content, and the specific area of leaves were measured. We found a higher iWUE of the plants on the ski slopes than outside, probably because the plants on the ski piste are exposed to a condition close to waterlogging that can lead them to regulate their stomata differently than the plants outside the pistes. This behaviour was observed particularly in Ranunculus acris and in Tussilago farfara, for these species the water surplus on the piste may have affected the plants' gas exchanges.


Assuntos
Monitoramento Ambiental/métodos , Água Doce/análise , Pradaria , Folhas de Planta/química , Esqui/normas , Neve/química , Altitude , Isótopos de Carbono/análise , Itália , Isótopos de Oxigênio/análise , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Estações do Ano
19.
Molecules ; 25(2)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968645

RESUMO

The abiotic photochemical reactions that take place naturally in sunlit surface waters can degrade many contaminants that pose concern to water bodies for their potentially toxic and long-term effects. This works aims at assessing the ability of European rivers to photoproduce reactive transient intermediates, such as HO• radicals and the excited triplet states of chromophoric dissolved organic matter (3CDOM*), involved in pollutant degradation. A photochemical mapping of the steady-state concentrations of these transients was carried out by means of a suitable modeling tool, in the latitude belt between 40 and 50°N. Such a map allowed for the prediction of the photochemical lifetimes of the phenylurea herbicide isoproturon (mostly undergoing photodegradation upon reaction with HO• and especially 3CDOM*) across different European countries. For some rivers, a more extensive dataset was available spanning the years 1990-2002, which allowed for the computation of the steady-state concentration of the carbonate radicals (CO3•-). With these data, it was possible to assess the time trends of the photochemical half-lives of further contaminants (atrazine, ibuprofen, carbamazepine, and clofibric acid). The calculated lifetimes were in the range of days to weeks, which might or might not allow for efficient depollution depending on the river-water flow velocity.


Assuntos
Rios/química , Poluentes Químicos da Água/análise , Água Doce/análise , Mapeamento Geográfico , Processos Fotoquímicos , Fotólise
20.
Environ Sci Pollut Res Int ; 27(8): 8586-8595, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31904098

RESUMO

The production of biodegradable plastics is considered to be a way to reduce plastic waste issue. Among others, oxo-degradant additives enable a faster degradation of plastics in the environment. However, the introduction of these new materials could provoke the release of substances potentially toxic in the environment. This work determined and compared the toxicity of leachates from various additivated polymers (polyethylene, PE; polypropylene, PP; polystyrene, PS) upon different test organisms: plants (Sorghum saccharatum, Lepidium sativum, Sinapis alba, and Vicia faba), crustacean (Daphnia magna), and luminescent bacteria (Vibrio fischeri). Daphnia magna survival was mainly affected by PS and PP leachates (72% and 61% effect, respectively) while PS notably reduced the reproduction rate. On plants, only PP exerted a negative effect (S. saccharatum IG% 32.4), while V. fischeri always showed values around 50%. The data integration, through the Toxicity Test Battery Integrated Index (TBI) approach, allowed to rank the leachates toxicity as PE > PS > PP. This result could be mainly ascribable to the highest metals content in PE since no difference with organic compounds analysis was evidenced. In conclusion, since the polymers exerted dissimilar toxicity, the additive could not be considered the sole responsible of the measured toxicity, but its role in the enhancement of the virgin polymers leachates effects can be solidly hypothesized.


Assuntos
Aliivibrio fischeri/química , Daphnia , Plásticos , Testes de Toxicidade/métodos , Animais , Daphnia/química , Água Doce/análise
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