Environmental assessment of PBDEs contamination in the Svitava River, Czech Republic.

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 (

Residues of selected antibiotics in the South Moravian Rivers, Czech Republic.

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.