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1.
Chemosphere ; 238: 124553, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31442776

RESUMO

Although, several recent greenhouse studies are beginning to address the uptake of pharmaceuticals and personal care products (PPCPs) by a variety of crops, few studies have assessed the effects of exposure to complex, realistic wastewater effluents on uptake. Hence, in this study, a greenhouse experiment was conducted in order to study the interactions occurring exclusively between PPCPs in soil, and in the edible plant part of beets (Beta vulgaris) after exposure to treated wastewater effluent. According to the findings, the interactions between the pharmaceuticals caffeine (CFN) with bisoprolol (BSP), carbamezapine (CMZ), clarithromycin (CMC), metoprolol (MPL), sulfamethoxazole (SMX), and trimethoprim (TMP) occurring in soil were almost 99% synergistic; it was noted variability in the interactive capacity of the pharmaceuticals; the concentrations of pharmaceuticals which measured did not affect unfavorably beet yield; interactions between the PPCPs via the PPCPs contribution in plant and soil affect the qualitative and quantitative characteristics of the beets.


Assuntos
Beta vulgaris/crescimento & desenvolvimento , Cosméticos/análise , Preparações Farmacêuticas/análise , Poluentes do Solo/análise , Solo/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Beta vulgaris/metabolismo , Cosméticos/metabolismo , Preparações Farmacêuticas/metabolismo , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/metabolismo
2.
Sci Total Environ ; 689: 245-257, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271990

RESUMO

In this study, the degradation of Nimesulide (NIM), a non-steroidal anti-inflammatory drug, using photolysis, heterogeneous (TiO2 in dispersion) and homogeneous (photo-Fenton reactant) photocatalysis, under simulated solar light (SSL) radiation, was investigated. Various parameters affecting the degradation rate of the target compound during the applied processes were optimized. The efficiency of all treatments used (direct photolysis; TiΟ2/SSL; TiΟ2/Η2Ο2/SSL; TiΟ2/S2Ο82-/SSL; Fe3+/H2O2/SSL; Fe3+/S2O82-/SSL and [Fe(C2O4)3]3-/H2O2/SSL) was evaluated by means of initial reaction rate and mineralization. Moreover, the generated transformation products (TPs) by each basic process (photolysis; TiΟ2/SSL and Fe3+/H2O2/SSL) were identified, using liquid chromatography coupled to high resolution mass spectrometry, and their formation kinetic profiles were given. The main transformation routes of NIM were hydroxylation and fragmentation, for all three treatments applied. Finally, toxicity measurements were conducted using Microtox bioassay in order to evaluate the potential risk of NIM and its TPs to aqueous organisms. Although, the acute toxicity increased during the first stages of treatment the final outcome lead to very low toxicity levels even within 60 min of TiO2/SSL treatment. Concluding, the obtained results suggest that the photocatalytic degradation of NIM can lead to its complete elimination and simultaneously to the detoxification of the solution.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Fotólise , Sulfonamidas/análise , Titânio/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Aliivibrio fischeri/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/toxicidade , Catálise , Cinética , Sulfonamidas/toxicidade , Luz Solar , Testes de Toxicidade Aguda , Águas Residuárias/toxicidade
3.
Environ Sci Pollut Res Int ; 24(5): 4791-4800, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27981483

RESUMO

In the present study, photo-Fenton and Fenton-like processes were investigated for the degradation and mineralization of the antineoplastic drug 5-fluorouracil (5-FU). For the optimization of photo-Fenton treatment under simulated solar light (SSL) radiation, the effects of several operating parameters (i.e., 5-FU concentration, Fe3+, and oxidant concentration) on the treatment efficiency were studied. According to the results, SSL/[Fe(C2Ο4)3]3-/Η2Ο2 process was the most efficient, since faster degradation of 5-FU and higher mineralization percentages were achieved. All the applied processes followed quite similar transformation routes which include defluorination-hydroxylation as well as pyrimidine ring opening, as demonstrated by the transformation products identified by high resolution mass spectrometry analysis. The toxicity of the treated solutions was evaluated using the Microtox assay. In general, low toxicity was recorded for the initial solution and the solution at the end of the photocatalytic treatment, while an increase in the overall toxicity was observed only at the first stages of SSL/Fe3+/Η2Ο2 and SSL/Fe3+/S2O82- processes.


Assuntos
Antineoplásicos/química , Fluoruracila/química , Peróxido de Hidrogênio/química , Luz
4.
Sci Total Environ ; 578: 257-267, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27856058

RESUMO

In the present study, the photocatalytic activity of TiO2-based photocatalysts toward degradation and mineralization of the anti-cancer drug 5-fluorouracil (5-FU) in aqueous phase was investigated under simulated solar and visible irradiation. Commercial TiO2 (P25) and N/S-doped TiO2 catalysts synthesized by a simple sol-gel method were used as photocatalysts. TiO2 P-25 was found to be the most photoactive catalyst for the removal of 5-FU, under simulated solar irradiation. Among N/S-doped TiO2 catalysts, the one with molar Ti:N/S ratio equal to 0.5 was the most efficient under simulated solar irradiation. In contrast, under visible irradiation the catalyst with equimolar Ti:N/S ratio showed the highest performance for the removal of 5-FU. Scavenging experiments revealed that HO radicals and h+ were the major reactive species mediating photocatalytic degradation of 5-FU using TiO2 P-25 and N/S-doped TiO2 catalysts, under simulated solar irradiation. On the other hand, the essential contribution of 1O2 and O2- in the degradation of 5-FU under visible light was proved. The transformation products (TPs) of 5-FU, were identified by LC-MS-TOF suggesting that defluorination followed by hydroxylation and oxidation are the main transformation pathways, under all the studied photocatalytic systems.


Assuntos
Fluoruracila/isolamento & purificação , Fotólise , Titânio/química , Catálise , Luz
5.
Chemosphere ; 83(3): 367-78, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21194726

RESUMO

Liquid-chromatography interfaced with time-of-flight mass spectrometry (LC-TOF/MS) was used to separate and characterize the transformation products arising from TiO(2)-photocatalytic degradation of the fungicide Fenhexamid (FEX) in aqueous solution under simulated solar irradiation. Prior to identification, irradiated solutions of FEX (10mgL(-1)) were concentrated by solid-phase extraction. Assignments of the mass spectra ions were aided by elemental composition calculations, comparison of structural analogues and available literature, and acquired knowledge regarding mass spectrometry of related heterocyclic compounds. The primary transformation intermediates identified were hydroxyl and/or keto-derivatives. Several positional isomers are typically produced as a consequence of the non-selectivity of the ()OH radical attack. Moreover, products resulted from the cleavage of the amide and NH-dichlorophenol bonds were formed. Finally, cyclic - benzo[d]oxazole intermediates are also formed through an intramolecular photocyclization process and cleavage of halogen - carbon bond. In the case of the hydroxy and/or keto-derivatives, the generic fragmentation scheme obtained from the interpretation of the ESI-TOF-MS data cannot be diagnostic to precisely localize the position of the entering substituent on the FEX molecule, and thus to characterize all its possible oxygenated derivatives by assigning a plausible structure with confidence. On the basis of identified products different pathways of photocatalytic degradation of FEX were proposed and discussed.


Assuntos
Amidas/química , Fungicidas Industriais/química , Fotólise , Titânio/química , Poluentes Químicos da Água/química , Amidas/análise , Cromatografia Líquida , Fungicidas Industriais/análise , Cinética , Espectrometria de Massas , Estrutura Molecular , Poluentes Químicos da Água/análise
6.
J Chromatogr A ; 1183(1-2): 38-48, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18241873

RESUMO

In the present study the photocatalytic degradation of bezafibrate (BZF), a lipid regulator agent, has been investigated using TiO(2) suspensions and simulated solar light. The study focus on the identification of degradation products (DPs) using powerful analytical techniques such as liquid chromatography time of flight mass spectrometry (LC-TOF-MS), gas chromatography mass spectrometry (GC-MS), and high-performance liquid chromatography with diode-array detection (HPLC-DAD). Each technique provided complementary information that enabled the identification of 21 DPs. Accurate mass measurements obtained by LC-TOF-MS provided the elucidation of 17 DPs. Mass errors lower than 2mDa, allowed the assignment of empirical formula for the mayor DPs to be determined confidently. Three DPs were identified by GC-MS through the structural information provided by full scan mass spectra obtained by electron impact (EI) ionization and two more by HPLC-DAD by comparing the retention times (t(R)) and the UV spectra of the unknown DPs with those of commercial standards. Based on this by-product identification a possible multi-step degradation scheme was proposed. The pathways include single or multiple hydroxylation of BZF with subsequent phenoxy ring opening and the cleavage of the amide and ether bonds.


Assuntos
Bezafibrato/efeitos da radiação , Catálise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Fotoquímica , Espectrometria de Massas por Ionização por Electrospray , Titânio
7.
Arch Environ Contam Toxicol ; 50(4): 603-13, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16446995

RESUMO

The concentrations of persistent organic pollutants, such as DDT and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), cyclodienes (Cycls), and polychlorinated biphenyls (PCBs), were measured in livers and subcutaneous fat tissues of six Accipitridae and four Falconidae bird species from different areas in Greece. This is the first report of persistent organochlorine (OC) pollutants in birds of prey tissues presented for Greece and the Eastern Mediterranean region. Accumulation patterns of OCs found in birds suggested that the predominant contaminants were p,p'-dichlorodiphenyldichloro-1,1-ethylene (DDE) and PCBs, whereas Cycls and HCHs occurred at low concentrations only. Concentration values of p,p'-DDE ranged from nondetected to 19,518.72 ng/g wet wt in livers and from nondetected to 2679.19 ng/g wet wt in fat. Total PCB levels ranged from 1.01 to 7419.43 ng/g and from 3.25 to 490.10 ng/g wet weight for liver and fat samples, respectively. Higher-chlorinated PCBs such as 118, 138, 153, and 180 predominated in both the liver and subcutaneous fat samples, a pattern comparable to that observed in birds from other European countries. No significant differences in mean concentrations of OCs are detected between species. Hepatic concentrations were in general higher than the fat concentrations showing depleted fat stores in most birds. Concentration ranges were also found in lower or similar levels to those reported for birds in other regions. Variation of OCs levels in bird tissues could be due to different causes of death, with a subsequent effect on body lipid levels, and different feeding and migration habits. The liver PCB levels reported in this study are below the concentrations currently believed to exert mortality or ecotoxicological effects. On the contrary, in some cases p,p'-DDE concentrations were higher than the reported effect values for birds of the same families and could be associated with sublethal effects.


Assuntos
Tecido Adiposo/metabolismo , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Fígado/metabolismo , Aves Predatórias/metabolismo , Animais , Monitoramento Ambiental , Poluentes Ambientais/farmacocinética , Grécia , Hidrocarbonetos Clorados/farmacocinética , Distribuição Tecidual
8.
J Chromatogr A ; 1016(2): 211-22, 2003 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-14601840

RESUMO

The photochemical behavior of the sunscreen agent octyl-dimethyl-p-aminobenzoic acid (ODPABA) was studied in different aqueous solutions and under different conditions. ODPABA photolysis was performed under laboratory conditions using a xenon light source and under natural sunlight conditions in sea, swimming pool as well as in distilled water. The influence of dissolved organic matter (DOM) on the degradation kinetics was also studied in the presence of various concentrations of humic acids (HA). The phototransformation was shown to proceed via pseudo-first-order reaction in all cases and the reaction rates followed the order: distilled water > swimming pool water > seawater, depending mainly on the presence of dissolved organic matter that retarded the photolysis reaction. Kinetic experiments were monitored with HPLC/UV-DAD and the half-lives (t 1/2) varied between 1.6 and 39 h in simulated solar irradiation and between 27 and 39 h in natural sunlight conditions. The product distribution during illumination was strongly dependent on the constitution of the irradiated media. Irradiation of the aqueous ODPABA solutions gave rise to several transformation products that were isolated by means of solid-phase extraction (SPE) and identified using GC-MS techniques. These were formed mainly through dealkylation and hydroxylation reactions and were detected in all aqueous solutions investigated. In the case of swimming pool water some additional byproducts were isolated and were tentatively identified as chlorinated intermediates, formed by the subsequent chlorination of the parent molecule as well as other intermediates.


Assuntos
Ácido 4-Aminobenzoico/química , Cloro/química , Desinfetantes/química , Protetores Solares/química , Piscinas , Água/química , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Fotólise , Espectrofotometria Ultravioleta , para-Aminobenzoatos
9.
Anal Bioanal Chem ; 374(5): 932-41, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12434252

RESUMO

Solid-phase microextraction (SPME) has been optimized and applied to the determination of the organophosphorus insecticides diazinon, dichlofenthion, parathion methyl, malathion, fenitrothion, fenthion, parathion ethyl, bromophos methyl, bromophos ethyl, and ethion in natural waters. Four types of SPME fiber coated with different stationary phases (PDMS, PA, PDMS-DVB, and CW-DVB) were used to examine their extraction efficiencies for the compounds tested. Conditions that might affect the SPME procedure, such as extraction time and salt content, were investigated to determine the analytical performance of these fiber coatings for organophosphorus insecticides. The optimized procedure was applied to natural waters - tap, sea, river, and lake water - spiked in the concentration range 0.5 to 50 micro g L(-1) to obtain the analytical characteristics. Recoveries were relatively high - >80% for all types of aqueous sample matrix - and the calibration plots were reproducible and linear (R(2)>0.982) for all analytes with all the fibers tested. The limits of detection ranged from 2 to 90 ng L(-1), depending on the detector and the compound investigated, with relative standard deviations in the range 3-15% at all the concentration levels tested. The SPME partition coefficients (K(f)) of the organophosphorus insecticides were calculated experimentally for all the polymer coatings. The effect of organic matter such as humic acids on extraction efficiency was also studied. The analytical performance of the SPME procedure using all the fibers in the tested natural waters proved effective for the compounds.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Inseticidas/isolamento & purificação , Compostos Organofosforados , Polímeros , Poluentes da Água/isolamento & purificação , Resinas Acrílicas , Dimetilpolisiloxanos , Grécia , Substâncias Húmicas , Indicadores e Reagentes , Inseticidas/análise , Métodos , Nylons , Polivinil , Poluentes da Água/análise
10.
Chemosphere ; 48(5): 475-85, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12146627

RESUMO

Organic booster biocides were recently introduced as alternatives to organotin compounds in antifouling products, after restrictions imposed on the use of tributyltin in 1987. In this study, the concentrations of three biocides commonly used as antifoulants, Irgarol 1051 (2-methylthio-4-tertiary-butylamino-6-cyclopropylamino-s-triazine), dichlofluanid (N-dichlorofluoromethylthio-N',N'-dimethyl-N-phenyl sulphamide) and chlorothalonil (2,4,5,6-tetrachloro isophthalonitrile) were determined in sediments from ports and marinas of Greece. Piraeus (Central port, Mikrolimano and Pasalimani marinas), Thessaloniki (Central port and marina), Patras (Central port and marina), Elefsina, Igoumenitsa, Aktio and Chalkida marinas were chosen as representative study sites for comparison with previous monitoring surveys of biocides in coastal sediments from other European countries. Samples were collected at the end of one boating season (October 1999), as well before and during the 2000 boating season. All the compounds monitored were detected at most of sites and seasonal dependence of biocide concentrations were found, with maxima during the period June-September, while the winter period (December-February) lower values were encountered. The concentrations levels ranged from 3 to 690 ng/g dw (dry weight). Highest levels of the biocides were found in marinas (690, 195 and 165 ng/g dw, for Irgarol, dichlofluanid and chlorothalonil respectively) while in ports lower concentrations were observed. Antifouling paints are implicated as the likely sources of biocides since agricultural applications possibly contributed for chlorothalonil and dichlofluanid inputs in a few sampling sites.


Assuntos
Compostos de Anilina/análise , Sedimentos Geológicos/química , Moluscocidas/análise , Nitrilos/análise , Triazinas/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Grécia , Pintura , Estações do Ano , Navios
11.
J Chromatogr A ; 967(2): 243-53, 2002 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-12685571

RESUMO

A method has been developed for the trace determination of two sunscreen constituents (2-hydroxy-4-methoxybenzophenone and octyldimethyl-p-aminobenzoic acid) in water samples, which are commonly used in commercial formulations. The method employs solid-phase microextraction (SPME) and gas chromatography with flame ionization and mass spectrometric detection. The technique was developed with headspace and direct sampling in order to demonstrate the applicability of these SPME extraction modes for the identification of these two UV absorbing compounds in waters. The main parameters affecting the SPME process, such as desorption time, extraction time profile, salt additives, pH, and temperature, were investigated. The poly(dimethylsiloxane) 100-microm and polyacrylate 85-microm fiber coatings were found to be the most efficient for the extraction of these compounds from aqueous matrices. Linear calibration curves in the wide range of 10-500 microg/l were obtained for both compounds yielding typical RSD values of 5-9% for both extraction modes. The recoveries were relatively high, 82-98%, with quantitation limits below 1 microg/l. A comparison between the proposed methods and the conventional multiresidue solid-phase extraction revealed that the proposed technique(s) can be reliably used for sunscreen residue measurement in water samples with satisfactory results.


Assuntos
Ácido 4-Aminobenzoico/análise , Benzofenonas/análise , Cromatografia Gasosa/métodos , Protetores Solares/análise , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Sensibilidade e Especificidade , Cloreto de Sódio , para-Aminobenzoatos
12.
J Chromatogr A ; 922(1-2): 243-55, 2001 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-11486869

RESUMO

Headspace solid-phase microextraction (HS-SPME) has been developed for the analysis of seven organophosphorus insecticides, i.e. diazinon, fenitrothion, fenthion, ethyl parathion, methyl bromophos, ethyl bromophos and ethion in natural waters. Their determination was carried out using gas chromatography with flame thermionic and mass spectrometric detection. To perform the HS-SPME, two types of fibre have been assayed and compared: polyacrylate (PA 85 microm), and polydimethylsiloxane (PDMS 100 microm). The main parameters affecting the HS-SPME process such as temperature, salt additives, memory effect, stirring rate and adsorption-time profile were studied. The method was developed using spiked natural waters such as ground, sea, river and lake water in a concentration range of 0.05-1 microg/l. The HS-SPME conditions were optimized in order to obtain the maximum sensitivity. Detection limits varied from 0.01 to 0.04 microg/l and relative standard deviations (RSD <17%) were obtained showing that the precision of the method is reliable. The method showed also good linearity for the tested concentration range with regression coefficients ranging between 0.985 and 0.999. Recoveries were in relatively high levels for all the analytes and ranged from 80 to 120%. Water samples collected from different stations along the flow of Kalamas river (NW Greece) were analyzed using the optimized conditions in order to evaluate the potential of the proposed method to the trace-level screening determination of organophosphorus insecticides. The analysis with HS-SPME has less background interference and the advantage of its non-destructive nature reveal the possibility of the repetitive use of the SPME fibre.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Inseticidas/análise , Compostos Organofosforados , Poluentes Químicos da Água/análise , Temperatura Alta , Reprodutibilidade dos Testes , Sais/química , Sensibilidade e Especificidade
13.
J Chromatogr A ; 893(1): 143-56, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-11043595

RESUMO

This study develops a method for the analysis of seven fungicides in environmental waters, using solid-phase microextraction (SPME). The analyzed compounds--dicloran, chlorothalonil, vinclozolin, dichlofluanid, captan, folpet and captafol--belong to different classes of chemical compound (chloroanilines, sulphamides, phthalimides and oxazolidines) and are used mainly in agriculture and as antifouling paints. Their determination was carried out by gas chromatography with electron-capture and mass spectrometric detection. To perform SPME, four types of fibre have been assayed and compared: polyacrylate (85 microm), polydimethylsiloxane (100 and 30 microm), carbowax-divinylbenzene (CW-DVB 65 microm) and polydimethylsiloxane-divinylbenzene (65 microm). The main parameters affecting the SPME process such as pH, salt additives, methanol content, memory effect, stirring rate and adsorption-time profile were studied. The method was developed using spiked natural waters such as ground water, sea water, river water and lake water in a concentration range of 0.1-10 microg/l. Limits of detection of studied compounds were determined in the range of 1-60 ng/l, by using electron-capture and mass spectrometric detectors. The recoveries of all fungicides were in relatively high levels (70.0-124.4%) and the average R2 values of the calibration curves were above 0.990 for all the analytes. The SPME conditions were finally optimized in order to obtain the maximum sensitivity. The potential of the proposed method was realized by applying it to the trace-level screening determination of fungicides and antifouling compounds in sea water samples originating from various Greek marinas.


Assuntos
Fungicidas Industriais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Poluentes Químicos da Água/análise , Calibragem , Concentração de Íons de Hidrogênio
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