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1.
Neuro Endocrinol Lett ; 37(Suppl1): 45-52, 2016 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-28263530

RESUMO

OBJECTIVES: The aim of this study was to assess the contamination level of aquatic ecosystems of the Svitava River, situated in the South Moravian Region (Czech Republic), by residues of selected brominated flame retardants. We isolated and determined seven indicator PBDE congeners in samples of surface water and bottom sediments using optimized analytical methods. DESIGN: Samples were collected from eight locations along the river basin, particularly near the larger cities in order to assess their possible impact on the aquatic ecosystems. Isolation of selected analytes was performed using the methods of liquid-liquid extraction and cold extraction. Column chromatography and rotary vacuum evaporation were used for the purification and pre-concentration of extracts. Final identification and quantification were carried out by gas chromatography coupled with electron capture detector (GC/ECD). RESULTS: The sum of PBDEs was calculated for individual BDE congeners. Average concentrations of the sum of PBDEs ranged from 56.35 to 614.0 µg.kg-1 of the dry matter in sediment, and concentrations under the detection limits (

Assuntos
Monitoramento Ambiental/métodos , Retardadores de Chama/toxicidade , Sedimentos Geológicos/análise , Éteres Difenil Halogenados/toxicidade , Rios , Testes de Toxicidade/métodos , Poluentes Químicos da Água/toxicidade , República Tcheca
2.
Neuro Endocrinol Lett ; 36 Suppl 1: 100-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26757126

RESUMO

OBJECTIVES: The aim of this study was to assess the contamination level of aquatic ecosystems of the Oslava and the Jihlava Rivers, and of the Nove Mlyny Water Reservoir, situated in the South Moravian Region (Czech Republic), by residues of selected veterinary pharmaceuticals. We isolated and determined 10 sulfonamide antibiotics in samples of surface water and bottom sediments using optimized analytical methods. DESIGN: A representative number of sampling sites in the entire basin of selected waters were chosen. Samples were collected particularly near the larger cities in order to assess their possible impact to the aquatic ecosystems. Extraction, pre-concentration and purification of samples were performed using optimized methods of solid phase extraction and pressurized solvent extraction. Final identification and quantification were carried out by high-performance liquid chromatography coupled with diode array detector. RESULTS: The concentration of sulfonamides in water samples were all under the limit of detection. Regarding sediment samples, sulfadimidine was found at most sampling sites; its highest values were recorded in the Jihlava River (up to 979.8 µg.kg(-1) dry matter). Other frequently detected sulfonamides were sulfamethoxazole and sulfamerazine. Most other sulfonamides were under the limit of detection or limit of quantification. CONCLUSIONS: Monitoring of antibiotic residues in the environment, especially in the aquatic ecosystem, is a current topic due to the growing worldwide use in both human and veterinary medicine. According to obtained results, we document the pollution of selected rivers and water reservoir by particular sulfonamides which basically reflects their application in veterinary medicine.


Assuntos
Antibacterianos/análise , Rios/química , Sulfamerazina/análise , Sulfametazina/análise , Sulfametoxazol/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão , República Tcheca , Resíduos de Drogas , Extração em Fase Sólida , Sulfonamidas/análise
3.
Interdiscip Toxicol ; 7(4): 177-83, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26109897

RESUMO

From the physical point of view, soil is a heterogenic polydisperse system. It often becomes a place of a secondary contamination during extinguishing uncontrolled areal fires in nature. Foam extinguishing agents (FEAs), used at these events, basically contain surface active substances and perfluorinated compounds. These tend to be captured in the soil matrix due to their specific properties. Contaminants could be partly flushed out with rainwater, which causes several times dilution of contamination and lower ecotoxic activity. However in the dry season, foam solution infiltrates into the bed soil without any dilution. This study deals with the direct influence of soil the sorption complex on ecotoxicity of five selected FEAs, i.e. Expyrol F 15, Finiflam F 15, Moussol APS F 15, Pyrocool B and Sthamex F 15. The substances tested were prepared in concentration of work solution and then applied on standard soil matrix LUFA 2.3. For experimental purposes, a column infiltration apparatus was designed and compiled. Filtrates were collected and then tested using the plant organisms Sinapis alba and Allium cepa L. The study compared ecotoxicologic effects of filtrates with an original work solution. Moussol APS F 15 seems to be the least ecotoxic of the FEAs tested. A direct influence of soil sorption complex onto ecotoxicity reduction was also established. This finding demonstrates the sorption ability of soil particles and ion exchange activity of the soil matrix. It is a positive finding for biota of aquatic environment, yet at the expense of those in soil.

4.
J Environ Sci (China) ; 25(1): 204-12, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23586316

RESUMO

Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of production and everyday consumption. Therefore there is a need to apply new and sufficiently sensitive analytical methods, which can detect the presence of these contaminants even in very low concentrations. This study is focused on the application of a reliable analytical method for the analysis of 10 selected drug residues, mainly from the group of non-steroidal anti-inflammatory drugs (salicylic acid, acetylsalicylic acid, clofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen, and dicofenac), in wastewaters and surface waters. This analytical method is based on solid phase extraction, derivatization by N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and finally analysis by comprehensive two-dimensional gas chromatography with Time-of-Flight mass spectrometric detection (GCxGC-TOF MS). Detection limits ranged from 0.18 to 5 ng/L depending on the compound and selected matrix. The method was successfully applied for detection of the presence of selected pharmaceuticals in the Svratka River and in wastewater from the wastewater treatment plant in Brno-Modrice, Czech Republic. The concentration of pharmaceuticals varied from one to several hundreds of ng/L in surface water and from one to several tens of isg/L in wastewater.


Assuntos
Cromatografia Gasosa/métodos , Espectrometria de Massas/métodos , Poluentes Químicos da Água/análise , Anti-Inflamatórios/análise
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