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1.
Mar Pollut Bull ; 176: 113466, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35219080

RESUMO

The status of contamination by chemical pollutants on large filter feeding sharks is still largely unknown. This study investigated for the first time the presence of legacy, emerging contaminants and trace elements in multiple tissues of basking sharks. In general, skin showed higher concentration of legacy and emerging contaminants probably due to pollutants being adsorbed onto the dermal denticles of the skin rather than accumulated in the tissue itself. Contaminants measured in both subcutaneous tissue and muscles appeared to strongly correlate with each other, indicating that the former might be a good proxy of muscle contamination in basking sharks. Considering the migratory nature of this species, longevity and feeding ecology, this species represents the perfect candidate to act as early warning bioindicator of regional contamination. In this context, non-lethal subcutaneous biopsies could allow the early detection of any temporal variation in the bioaccumulation of pollutants in the Mediterranean Sea.


Assuntos
Tubarões , Poluentes Químicos da Água , Animais , Mar Mediterrâneo , Tubarões/fisiologia
2.
Mar Pollut Bull ; 124(1): 121-129, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28712769

RESUMO

Biota-Sediment Accumulation Factors (BSAFs) of nonylphenols (NPs) and polycyclic aromatic hydrocarbons (PAHs) in Ruditapes philippinarum from the Venice Lagoon (Italy) were determined with the aim to verify whether the routine biomonitoring studies are reliable in contaminated sites. Clams and sediments were collected in field campaigns (October 2003 to June 2004) in three sites of the Venice Lagoon. Results showed that Marghera and Campalto sediments were more contaminated by NPs and PAHs than Poveglia. Different trends were observed in the contamination of clams with the highest BSAFs found at Poveglia. BSAF trend appeared to be inversely related to the contaminant pressure on the sites. These results suggest that clam bioaccumulation is not always representative of the chemical pressure on aquatic biota. The direct correlation between sediment and biota concentrations in contaminated sites can be lost as a function of the site-specific conditions such as sediment toxicity and food availability.


Assuntos
Bivalves/química , Sedimentos Geológicos/análise , Fenóis/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Animais , Bivalves/metabolismo , Monitoramento Ambiental/métodos , Itália , Fenóis/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo
3.
J Chromatogr A ; 1453: 62-70, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27237594

RESUMO

An on-line TFC (Turbulent Flow Chromatography) clean up procedures coupled with UHPLC-MS/MS (Ultra High Performance Liquid Chromatography Mass Spectrometry) multi-residue method was developed for the simultaneous determination of 8 perfluroalkyl carboxylic acids (PFCA, from 5 to 12 carbon atoms) and 3 perfluoroalkyl sulfonic acids (PFSA, from 4 to 8 carbon atoms) in environmental solid matrices. Fast sample preparation procedure was based on a sonication-assisted extraction with acetonitrile. Phospholipids in biological samples were fully removed by an off-line SPE purification before injection, using HybridSPE(®) Phospholipid Ultra cartridges. The development of the on-line TFC clean-up procedure regarded the choice of the stationary phase, the optimization of the mobile phase composition, flow rate and injected volume. The validation of the optimized method included the evaluation of matrix effects, accuracy and reproducibility. Signal suppression in the analysis of fortified extracts ranged from 1 to 60%, and this problem was overcome by using isotopic dilution. Since no certified reference materials were available for PFAS in these matrices, accuracy was evaluated by recoveries on spiked clam samples which were 98-133% for PFCAs and 40-60% for PFSAs. MLDs and MLQs ranged from 0.03 to 0.3ngg(-1) wet weight and from 0.1 to 0.9ngg(-1) wet weight respectively. Repeatability (intra-day precision) and reproducibility (inter-day precision) showed RSD from 3 to 13% and from 4 to 27% respectively. Validated on-line TFC/UHPLC-MS/MS method has been applied for the determination of perfluoroalkyl acids in different solid matrices (sediment, fish, bivalves and bird yolk).


Assuntos
Cromatografia Líquida/métodos , Fluorocarbonos/análise , Fluorocarbonos/isolamento & purificação , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Animais , Bivalves/química , Ácidos Carboxílicos/análise , Cromatografia Líquida de Alta Pressão , Peixes , Sedimentos Geológicos/química , Fosfolipídeos/isolamento & purificação , Reprodutibilidade dos Testes , Ácidos Sulfônicos/análise
4.
Ecotoxicol Environ Saf ; 69(1): 49-57, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17320173

RESUMO

To investigate how particulate materials and the toxicity of a polluted river can affect biomass production of a particle feeding organism, monthly water samples of the River Lambro were collected upstream and downstream from major pollution sources. These samples were characterized for physical and chemical endpoints, and tested for acute and chronic toxicity (7-day) using Ceriodaphnia dubia. Comparing the effects of unfiltered and filtered water samples, we showed that: (a) despite the higher contamination of the downstream reach, unfiltered (whole) downstream samples often supported a higher biomass production of C. dubia than upstream samples; (b) filtering downstream water samples and thereby removing suspended particulate matter (SPM) controlled this compensatory effect and resulted in a clear inhibition of daphnid biomass production; (c) despite the compensatory and likely nutritional role of particulate materials, an inverse relationship was found between daphnid biomass production and the content of organic carbon of SPM, as well as between the SPM organic content and the temperature of the river. These results show that SPM of the downstream reach can simultaneously exert trophic and toxic effects, and their interaction determines the final result but under the control of major system factors such as water temperature.


Assuntos
Crustáceos/fisiologia , Monitoramento Ambiental/métodos , Cadeia Alimentar , Rios/química , Poluentes Químicos da Água/toxicidade , Animais , Biomassa , Crustáceos/efeitos dos fármacos , Itália , Fatores de Tempo , Reforma Urbana
5.
Arch Environ Contam Toxicol ; 53(4): 571-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17657455

RESUMO

The present study is the first dealing with the accumulation and elimination of 4-nonylphenol (NP) by the Manila clam, Tapes philippinarum. Specimens of T. philippinarum were exposed to NP-spiked seawater, and the NP contents in whole soft tissue, gills, digestive gland, and haemolymph were measured. Actual NP concentrations in seawater and microalgae (Isochrysis galbana) used for feeding were also determined, and the algal bioconcentration factor (BCF) value (640 ml/g) was calculated. Volatilisation was the main cause of dissipation of NP from experimental tanks, attaining up to 78% of the NP added. NP accumulated by algae used for feeding was negligible with respect to the total added NP, and we concluded that in our experiments, clams accumulated NP mainly from water and not food intake. Accumulation followed a two-compartment, first-order rate coefficient model, with an uptake rate coefficient of 13.8 +/- 0.6 mL g(-1)h(-1)(fresh weight [fw]) and an elimination coefficient of 0.0070 +/- 0.0005 h(-1). Ninety percent of the steady state was reached after 14 days of exposure, and the BCF value at the steady state was 1958 +/- 158 mL g(-1) fw (1.8 +/- 0.2 x 10(5) based on lipid weight). Slightly less than 50% of NP bioaccumulated through water was allocated into the gills, whereas the rest was found in the digestive gland. In the first 8 hours, clams eliminated 51% of the NP accumulated, and only 2% of the NP accumulated was detected in the clams at the end of the elimination phase (day 14). Two-compartment first-order decay model described the elimination of the accumulated NP by considering the clam as two compartments each with a different elimination rate. The sudden elimination of NP in the initial hours can be attributed to the elimination of NP accumulated into the gills and readily available for excretion (k ( e ) = 0.30 +/- 0.07 h(-1)). The slower step of the elimination process should be the mobilisation of NP accumulated in internal organs, which must be carried into the haemolymph for excretion (k(e) = 0.0091 +/- 0.0002 h(-1)). Because T. philippinarum has been demonstrated to accumulate NP dissolved in water, high NP levels can be hypothesised in clams from highly contaminated environments. This research was performed according to all national and international guidelines for animal welfare.


Assuntos
Bivalves/metabolismo , Fenóis/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Fenóis/análise , Água do Mar/análise , Distribuição Tecidual
6.
J Chromatogr A ; 1039(1-2): 155-9, 2004 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-15250418

RESUMO

Acrylamide, a known neurotoxin and putative human carcinogen, has been included among the substances to be monitored in drinking water according to the European Union Directive 98/83 on potable water. This paper reports a new method based on the combination of ion-exclusion chromatographic separation and MS detection. Samples of drinking water have been directly injected in the microbore ICE-AS1 column and detected in the selected-ion monitoring mode by a single quadrupole system with electrospray ionization. Chromatographic conditions, such as eluent composition and flow rate, have been optimized by a central composite design experiment. Statistical analysis of data showed that the amount of acetonitrile fraction in the eluent mixture, composed by acetonitrile and formic acid solution, is the variable that most influences retention of the acrylamide peak. After optimization of MS detection parameters, this method has been validated for spiked drinking water samples. The effect of large-volume injection (up to 500 microl) has been also explored. Linearity was evaluated from 0.5 to 5 microg l(-1). Repeatability, expressed as R.S.D., was 16 and 12% at 0.5 and 1 microg l(-1) respectively. The limit of detection was 0.20 ppb with 500 microl injection volume.


Assuntos
Acrilamida/análise , Cromatografia por Troca Iônica/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Abastecimento de Água/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
J Chromatogr A ; 1022(1-2): 1-7, 2004 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-14753765

RESUMO

A readily applicable method based on extraction by aqueous non-ionic surfactant solutions (Tween 80) and RP-HPLC coupled to fluorescence detection, has been developed for the simultaneous determination of the phenolic endocrine disrupting chemicals (EDCs) nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenol diethoxylate (NP2EO) and bisphenol A (BPA) in environmental solid matrices. Clean up of sample extracts was performed on Si-C18 solid phase extraction (SPE) cartridges. The overall Tween 80 extraction-SPE-RP-HPLC procedure was validated for accuracy and precision by analyzing sediment samples spiked with known amounts of EDCs. Recoveries for NP, NP1EO, NP2EO and BPA and limits of detection are in agreement with conventional extraction methods. The developed methodology was successfully applied to the analysis of target compounds in Italian river sediments, river suspended matter and benthonic macroinvertebrate organisms (oligochaetes Lumbriculus variegatus). Results confirmed that this relatively simple procedure performed satisfactorily in the determination of phenolic EDCs in environmental solid matrices of different complexity and that it can be a suitable alternative method to conventional systems even for routine analyses.


Assuntos
Glândulas Endócrinas/efeitos dos fármacos , Poluentes Ambientais/isolamento & purificação , Polissorbatos/química , Tensoativos/química , Poluentes Ambientais/toxicidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Mar Pollut Bull ; 42(10): 887-94, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11693643

RESUMO

The modifications of several biomarkers were investigated in flounder (Platichthys flesus) when exposed in the laboratory to sediment samples collected from the Northern Adriatic Sea. Besides clean sand used as a control substrate, fish were exposed to sediments sampled offshore the delta of the Po River, the harbour of Trieste, and from the industrial harbour of Venice (Porto Marghera). After six days of exposure, the enzyme activities ethoxyresorufin-O-deethylase (EROD), UDP glucuronyltransferase (UDPGT), glutathione S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GPx), were assayed in fish liver. In addition, the contents of reduced glutathione (GSH), nonprotein thiols (SH), total sugars and extractable lipids were also determined in hepatic tissue, as well as the number of micronucleated hepatocytes and biliary concentrations of fluorescent aromatic compounds (FAC). Despite some variability within treatment groups, differences among exposed organisms were evident and consistent with known contaminant levels of sampled areas. Microsomal activities (EROD, UD-PGT) and FAC levels were the most sensitive exposure indicators. Variations in the other biomarkers showed only tendencies which although not statistically significant were generally consistent with the contamination pattern.


Assuntos
Biomarcadores/análise , Linguado/metabolismo , Sedimentos Geológicos/química , Fígado/enzimologia , Poluentes da Água/metabolismo , Animais , Bile/química , Carboidratos/análise , Citocromo P-450 CYP1A1/análise , Exposição Ambiental , Monitoramento Ambiental , Glucuronosiltransferase/análise , Glutationa/análise , Glutationa Peroxidase/análise , Glutationa Redutase/análise , Glutationa Transferase/análise , Hepatócitos/ultraestrutura , Hidrocarbonetos Aromáticos/análise , Fígado/química , Micronúcleos com Defeito Cromossômico/ultraestrutura , Oceanos e Mares , Compostos de Sulfidrila/análise , Poluentes da Água/análise
9.
J Chromatogr A ; 925(1-2): 297-301, 2001 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-11519814

RESUMO

The pressurised liquid extraction (PLE) of 4-nonylphenol (4-NP) with methanol (100 degrees C and 100 atm) from river sediments was compared with methanolic Soxhlet extraction, the standard method for the sediment analysis. The PLE method showed a precision (average RSD ranged from 6 to 33%) and an accuracy (average recovery 85 and 87% for 4-NP and 4-NPE, respectively) comparable to those of Soxhlet. The extraction was performed on river sediments and no organic carbon content influence was found. The comparative study presented in this paper demonstrates that PLE is an alternative suitable extraction method for 4-nonylphenol and 4-nonylphenol ethoxylate determination in sediments.


Assuntos
Cromatografia Líquida/métodos , Sedimentos Geológicos/química , Fenóis/isolamento & purificação , Fenóis/química , Pressão
10.
J Chromatogr A ; 920(1-2): 231-8, 2001 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-11453004

RESUMO

A novel, rapid ion-chromatographic method for screening anionic pollutants in ground water, based on both conductivity and postcolumn spectrophotometric detection, has been developed. A relatively rapid separation of more than ten inorganic and polarizable anions was achieved by coupling an high capacity, hydroxide selective anion-exchange columns (Dionex IonPac AS16) supplied with an electrolytic eluent generator operating in gradient mode. The good control of the selectivity allowed the determination of polarizable anions including arsenate, thiocyanate, thiosulfate and perchlorate without interference from major components present at levels greater than 100 mg l(-1). This method was applied to the determination of arsenate in ground water samples collected in industrial and agricultural zones of Lombardia (Northern Italy). No traces of arsenate were detected in any sample, but added arsenate cannot be revealed by chromatographic analyses. This fact can be attributed to different causes, from reduction to the more reduced arsenic form to precipitation or dissolution in organic or inorganic based colloids. Oxidation with hydrogen peroxide seems to be useful for a partial recovery of added arsenate, but a stronger oxidation method, compatible with chromatographic separation, must be studied.


Assuntos
Arseniatos/análise , Cromatografia Líquida/métodos , Poluentes Químicos da Água/análise , Ânions , Itália , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
11.
J Chromatogr A ; 847(1-2): 279-84, 1999 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-10431365

RESUMO

Bromate is a well known by-product produced by the ozonation of drinking water; the allowed concentration for human consumption has to be regulated to low microgram l-1 range. By using a high-capacity anion-exchange column, it should be possible to determine bromate at this low concentration by direct injection of a very large volume (up to 1 ml) without any sample preconcentration and pretreatment. The feasibility of this technique for the determination of bromate in drinking water has been explored in our work. The experimental results showed that matrix effect, due to inorganic ions contained in drinking water, strongly influenced the chromatographic behaviour of the bromate peak. The increase of the total ion content led to a correlated decrease in the efficiency of the analyte peak so that effective detection limits depended on the matrix composition. In this work chromatographic parameters (efficiency, asymmetry and resolution) of bromate peak are discussed in relation to the concentration of the main inorganic anions, and the injection volume (from 250 microliters to 1 ml).


Assuntos
Bromatos/análise , Cromatografia Líquida/métodos , Abastecimento de Água/análise , Calibragem , Sensibilidade e Especificidade
12.
J Chromatogr A ; 834(1-2): 363-85, 1999 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-10189695

RESUMO

The use of capillary electrophoresis for the determination of inorganic species in environmental samples is reviewed. Topics covered include the separation of inorganic anions, inorganic cations, transition metal cations and organometals in different environmental matrices, such as atmospheric deposition, atmospheric aerosols, gases, natural waters, waste waters, soil, sediment and marine biological samples. Cited literature is gathered according to the type of matrix, so that the focus is on the discussion of matrix effects rather than on the method development for a single class of compounds. For each matrix, surveyed methods are tabulated in order to assist the method selection. Innovative applications of capillary electrophoresis to advanced environmental research are also emphasised.


Assuntos
Eletroforese Capilar , Meio Ambiente , Ar/análise , Eletroforese Capilar/métodos , Poluentes Ambientais/análise , Resíduos Industriais/análise , Água do Mar/análise , Solo/análise , Água/química
13.
J Chromatogr A ; 864(2): 263-70, 1999 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-10669294

RESUMO

Bromate is a well known by-product produced by the ozonisation of drinking water; the allowed concentration for human consumption has to be regulated to the low microg l(-1) range. A direct injection, ion chromatographic method was developed using a tetraborate eluent with serially connected conductivity and spectrophotometric detection. Bromate was detected after post-column reaction with fuchsin at 520 nm. Sample capacity was investigated by injecting large volumes (up to 6 ml) using a high total hardness and chloride tap water. Linear correlation of bromate response with volumes from 1 ml to 6 ml was demonstrated, the main limitation being the overlapping of the chloride peak with bromate. Up to 1.5 ml sample can be injected without any pre-treatment. With more than 1.5 ml injection volume, a sample pre-treatment with a cartridge in Ag and H form, followed by a 10 min degassing in an ultrasonic bath, was needed. This method was validated by analysing secondary reference materials and real samples from a drinking water treatment plant. The method was linear from the limit of quantification to 20 microg l(-1). Reproducibilities in tap water were 18% (5 microg l(-1), n=12) and 21% (1 microg l(-1), n=4) respectively for 1.5 and 6 ml injection volumes with conductivity detection, and 17% at 0.5 microg l(-1) (n=9) with spectrophotometric detection. Calculated detection limits were 0.5 microg l(-1) (6 ml) ahd 2 microg l(-1) (1.5 ml) for conductivity detection and 0.3 microg l(-1) (1.5 ml) for spectrophotometric detection.


Assuntos
Bromatos/análise , Abastecimento de Água/análise , Calibragem , Carbonatos/análise , Cloretos/análise , Cromatografia por Troca Iônica , Condutividade Elétrica , Ozônio/química , Espectrofotometria
14.
J Chromatogr ; 624(1-2): 103-52, 1992 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-1494001

RESUMO

Chromatographic methods for the determination of water- and fat-soluble vitamins in foods are reviewed. For each vitamin, sample preparation, detection problems and chromatographic conditions are presented and discussed. High-performance liquid chromatography (HPLC) is becoming a standard method in vitamin assay, especially for routine work. HPLC systems can be automated using in-line solid-phase extraction and column switchings, resulting in very sensitive methods, even when simple UV detection is employed.


Assuntos
Cromatografia/métodos , Análise de Alimentos/métodos , Vitaminas/análise , Solubilidade
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