RESUMEN
In this work, the environmental distribution of steroid compounds and the level of sewage-derived contamination were assessed using sterol ratios in the confluence area of two major rivers in the Serbian capital, where raw sewage is discharged without any treatment. Special attention was paid to steroids partitioning between the dissolved and suspended phases of river and wastewater samples, since steroids tend to easily bind to particulate matter. The efficiency of sterol removal in two wastewater treatment plants in Serbia was also evaluated. Human/animal sterols coprostanol and cholesterol, and phytosterol ß-sitosterol were the dominant compounds in all water samples. The sterol abundance pattern in river water was different from that in raw sewage, indicating a more pronounced biogenic input, as well as greater impact of wastewater discharges on the composition of the suspended phase. Severe contamination of the investigated area was determined, with the Danube being more contaminated than the Sava River due to different hydrodynamic conditions leading to significantly higher sterol levels in the suspended particulate matter. It was also shown that the greater part of human/animal sterols and phytosterols present in river water samples (83.0⯱â¯11.9â¯% and 87.1⯱â¯15.2â¯%) and wastewater samples (92.1⯱â¯6.8â¯% and 95.0⯱â¯5.7â¯%) was bound to suspended material compared to the dissolved phase, emphasizing the need to consider and analyze both water phases in the tracing of steroid-based environmental pollution in order to obtain a realistic picture of steroid contamination and their fate in the aquatic environment. A high removal rate (>98â¯%) of coprostanol and cholesterol during wastewater treatment was determined and only the coprostanol/(coprostanol + cholestanol) ratio was found to be sensitive enough to be affected by an improvement in the quality of treated wastewater.
Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Animales , Colestanol/análisis , Monitoreo del Ambiente , Humanos , Material Particulado , Ríos , Aguas del Alcantarillado/análisis , Esteroides/análisis , Esteroles/análisis , Aguas Residuales , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
Recent studies show that lanthanides (Ln) are becoming emerging pollutants due to their wide application in new technologies, but their environmental fate, transport, and possible accumulation are still relatively unknown. This study aims to determine major and trace elements including Ln in the Danube River sediment which either belong or close to the Iron Gate Reservoir. The Iron Gate Reservoir is characterized by accumulation of sediments as an effect of building hydropower dam Iron Gate I. The surface sediments were collected on the Danube River-1141 to 864 km and three tributaries along this waterway. Two samples of deep sediments were used for comparison. The results indicate the significant upward enrichment of Zn, Sb, Cr, Nd, and Dy in sediments belongs to the Iron Gate Reservoir. The sample 4-Smed is labelled as a hot spot of contamination with Zn, Cr, As, Sb, Nd, and Dy. Also, a trend of increasing concentration in the time period from 1995 to 2016 was found for elements Zn, Cr, and Ni in sediment samples in the Iron Gate Reservoir. Chemometric analysis shows the grouping of sample sites into clusters characterized by the following properties: (i) increased concentration of all measured elements (samples within the Iron Gate Reservoir); (ii) increased Cu concentration (11-Pek); and (iii) lower concentrations of the measured elements (deep sediments). The data presented hereby contribute to the monitoring of pollution of the River Danube sediments and give the first view of Ln profile in the studied sediments.
Asunto(s)
Elementos de la Serie de los Lantanoides , Metales Pesados , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Hierro , Metales Pesados/análisis , Ríos , Contaminantes Químicos del Agua/análisisRESUMEN
This paper presents a case study of a massive fish mortality during a Cylindrospermopsis raciborskii bloom in Aleksandrovac Lake, Serbia in mid-December 2012. According to a preliminary investigation of the samples taken on November 6 before the fish mortalities and to extended analyses of samples taken on November 15, no values of significant physicochemical parameters emerged to explain the cause(s) of the fish mortality. No industrial pollutants were apparent at this location, and results excluded the likelihood of bacterial infections. Even after freezing, the dissolved oxygen concentration in the water was sufficient for fish survival. High concentrations of chlorophyll a and phaeophytin occurred in the lake, and phytoplankton bloom samples were lethal in Artemia salina bioassays. A bloom of the cyanobacterium C. raciborskii was recorded during November. Although the A. salina bioassays indicated the presence of toxic compounds in the cyanobacterial cells, the cyanotoxins, microcystins, cylindrospermopsin and saxitoxin were not detected.
Asunto(s)
Cylindrospermopsis/crecimiento & desarrollo , Monitoreo del Ambiente , Peces/fisiología , Floraciones de Algas Nocivas , Lagos/microbiología , Contaminantes Químicos del Agua/toxicidad , Alcaloides , Animales , Toxinas Bacterianas/toxicidad , Toxinas de Cianobacterias , Microcistinas , Uracilo/análogos & derivados , Uracilo/toxicidad , Microbiología del AguaRESUMEN
The aim of this study was the development of analytical methods for the simultaneous determination of 25 selected pharmaceuticals, metabolites, and pesticides, belonging to the various chemical classes, in river sediments and their corresponding surface and ground water with the purpose of monitoring the contamination levels. The methods were based on the solid-phase extraction as the sample preparation method for water samples, and the ultrasonic solvent extraction for the sediment samples, followed by the liquid chromatography-tandem mass spectrometry. High recoveries were achieved for extraction from both water and sediment samples for the majority of analytes. Low limits of detection were achieved for all investigated compounds in the water sample (1-5 ng L(-1)) as well as in the sediment (1-3 ng g(-1)). Applicability of the developed methods was demonstrated by determination of pharmaceutical and pesticide residues in 30 surface water, 44 groundwater, and 5 sediment samples from the Danube River Basin in Serbia. Sixty percent of target compounds were detected in environmental samples. The most frequently detected analytes in river sediments were the pesticides dimethoate and atrazine, while carbamazepine and metamizole metabolites 4-AAA and 4-FAA were the most frequently found in water samples.
Asunto(s)
Monitoreo del Ambiente , Agua Subterránea/química , Plaguicidas/análisis , Preparaciones Farmacéuticas/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Cromatografía Liquida , Espectrometría de Masas , Serbia , Extracción en Fase SólidaRESUMEN
Pharmaceuticals are emerging contaminants with damaging effects to the environment and human health. Their presence in surface and especially groundwaters is regarded as detrimental, as they can ultimately reach drinking water. The aim of this work was to monitor pharmaceutical contamination of the Danube River and its tributaries in Serbia, and to assess the potential of their passing through all natural filtrations and reaching the groundwater. A total of 70 surface and groundwater samples was collected at 38 sampling sites at the Danube in Serbia. They were taken in five sampling campaigns performed in summer and autumn of 2009 and winter, spring and autumn of 2010. Samples were analyzed using a previously developed method which includes solid-phase extraction followed by liquid chromatography-tandem mass spectrometry.