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Abstract

Antibiotics are a group of substances potentially harmful to the environment. They can play a role in bacterial resistance transfer among pathogenic and non-pathogenic bacteria. In this experiment three representatives of medically important chemotherapeutics, confirmed to be present in high concentrations in wastewater treatment plants with HPLC analysis were used: erythromycin, sulfamethoxazole and trimethoprim. Erythromycin concentration in activated sludge was not higher than 20 ng L−1. N-acetylo-sulfamethoxazole concentration was 3349 ± 719 in winter and 2933 ± 429 ng L−1 in summer. Trimethoprim was present in wastewater at concentrations 400 ± 22 and 364 ± 60 ng L−1, respectively in winter and summer. Due to a wide variety of PCR-detectable resistance mechanisms towards these substances, the most common found in literature was chosen. For erythromycin: erm and mef genes, for sulfamethoxazole: sul1, sul2, sul3 genes, in the case of trimethoprim resistance dhfrA1 and dhfr14 were used in this study. The presence of resistance genes were analyzed in pure strains isolated from activated sludge and in the activated sludge sample itself. The research revealed that the value of minimal inhibitory concentration (MIC) did not correspond with the expected presence of more than one resistance mechanisms. Most of the isolates possessed only one of the genes responsible for a particular chemotherapeutic resistance. It was confirmed that it is possible to monitor the presence of resistance genes directly in activated sludge using PCR. Due to the limited isolates number used in the experiment these results should be regarded as preliminary.

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Authors and Affiliations

Aleksandra Ziembińska-Buczyńska
Ewa Felis
Justyna Folkert
Anna Meresta
Dominika Stawicka
Anna Gnida
Joanna Surmacz-Górska
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Abstract

Dye wastewater is one of typically non-biodegradable industrial effluents. A new process linking Fenton’s oxidation with biological oxidation proposed in this study was investigated to degrade the organic substances from real dye wastewater. During the combination process, the Fenton’s oxidation process can reduce the organic load and enhance biodegradability of dye wastewater, which is followed by biological aerated filter (BAF) system to further remove organic substances in terms of discharge requirement. The results showed that 97.6% of chemical oxygen demand (COD) removal by the combination process was achieved at the optimum process parameters: pH of 3.5, H2O2 of 2.0 mL/L, Fe(II) of 500 mg/L, 2.0 h treatment time in the Fenton’s oxidation process and hydraulic retention time (HRT) of 5 h in the BAF system. Under these conditions, COD concentration of effluent was 72.6 mg/L whereas 3020 mg/L in the influent, thus meeting the requirement of treated dye wastewater discharge performed by Chinese government (less than 100 mg/L). These results obtained here suggest that the new process combining Fenton’s oxidation with biological oxidation may provide an economical and effective alternative for treatment of non-biodegradable industrial wastewater.

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Authors and Affiliations

Haiming Zou
Wanzheng Ma
Yan Wang
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Abstract

Presented study aimed to determine metals distribution on the quartz fiber filters surface coated with particulate matter by using high and low-volume samplers. The distribution pattern was tested using two different sub-sampling schemes. Each sub-sample was mineralized in the nitric acid in a microwave oven. An analysis was performed by means of atomic absorption spectroscopy with electrothermal atomization GF-AAS technique, and the determined elements were: As, Cd, Pb and Ni. A validation of the analytical procedure was carried out using NIES 28 Urban Aerosols standard reference material.

It was assumed that metal is distributed uniformly if its normalized concentrations on a single sub-sample is within ±15% of the mean concentration over the whole filter. The normalized concentrations values exceed this range, indicating a non-homogenous metals distribution. There were no statistically significant differences in metals concentrations between particular sub-samples in the function of its position along the filters diameter.

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Authors and Affiliations

Kamila Widziewicz
Wioletta Rogula-Kozłowska
Krzysztof Loska
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Abstract

People spend most of their time in indoor environments and, consequently, these environments are more significant for the contribution of the daily pollutant exposure than outdoors. In case of children, a great part of their time is spent at school. Therefore, evaluations of this microenvironment are important to assess their time-weighted exposure to air pollutants.

The aim of this study was to assess the children exposure to bioaerosols at schools from two different types of areas, urban and rural. A methodology based upon passive sampling was applied to evaluate fungi, bacteria and pollens, simultaneously with active sampling for fungi and bacterial assessment. Results showed very good correlations between sampling methods, especially for summer season. Passive sampling methodologies presented advantages such as no need of specific and expensive equipment, and they allow achieving important qualitative information.

The study was conducted in different periods of the year to study the seasonal variation of the bioaerosols. Fungi and pollen presented higher levels during the summer time whereas bacteria did not present a seasonal variation. Indoor to outdoor ratios were determined to assess the level of outdoor contamination upon the indoor environment. Levels of fungi were higher outdoor and bacteria presented higher concentrations indoors.

Indoor levels of bioaerosols were assessed in primary schools of urban and rural areas, using the active method along with a passive sampling method. Very good correlations between methods were found which allow the use of the passive sampling method to supply important and reliable qualitative information of bioaerosols concentrations in indoor environments. Seasonal variation in bioaerosols concentrations were found for fungi and pollen. Concentrations of fungi and bacteria above AMV (Acceptable Maximum Value) were found for most of the studied classrooms showing the importance of this microenvironment for the high exposure of children to bioaerosols.

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Authors and Affiliations

Nuno Canha
Susana Marta Almeida
Maria do Carmo Freitas
Hubert Th. Wolterbeek
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Abstract

The study was conducted on the Biała Lądecka River which is a mountain river. It is similar to many European mountain rivers in terms of hydromorphology and catchment management. The aim of this study was to determine the bioconcentration factors of heavy metals (Pb, Cd, Hg, Ni, Cr, Cu and Zn) in Ranunculus aquatile (L.) Dumort., Fontinalis antipyretica (L. ex Hedw.), and Lemanea fluviatilis (L.) C.Ag. The content of metals in water, sediment, and submerged plants was determined. The metal concentrations in plants can be arranged as follows: Hg < Cd < Cr < Ni < Cu < Pb <Zn. The highest concentrations of Hg, Ni, Cr, and Cu were observed in F. antipyretica, but the highest concentrations of Pb, Cd, and Zn were in R. aquatile. L. fluviatilis always contained the least amounts of heavy metals. Bioconcentration factors (BCFs) were lowest in L. fluviatilis and highest in F. antipyretica. Among the analyzed metals, plants accumulated the highest amount of Zn, and the least of Hg. The BCFs for Zn were from 24111 (in L. fluviatilis) to 97574 (in R. aquatile), and BCFs for Hg were from 29 (in L. fluviatilis) to 226 (in F. antipyretica).

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Authors and Affiliations

Przemysław Pokorny
Joanna Pokorny
Wojciech Dobicki
Magdalena Senze
Monika Kowalska-Góralska
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Abstract

The aim of this article is to evaluate the quality of the Danube River in its course through Serbia as well as to demonstrate the possibilities for using three statistical methods: Principal Component Analysis (PCA), Factor Analysis (FA) and Cluster Analysis (CA) in the surface water quality management. Given that the Danube is an important trans-boundary river, thorough water quality monitoring by sampling at different distances during shorter and longer periods of time is not only ecological, but also a political issue. Monitoring was carried out at monthly intervals from January to December 2011, at 17 sampling sites. The obtained data set was treated by multivariate techniques in order, firstly, to identify the similarities and differences between sampling periods and locations, secondly, to recognize variables that affect the temporal and spatial water quality changes and thirdly, to present the anthropogenic impact on water quality parameters.

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Authors and Affiliations

Danijela Voza
Milovan Vukovic
Ljiljana Takic
Djordje Nikolic
Ivana Mladenovic-Ranisavljevic
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Abstract

Heavy metal pollution of soil is a significant environmental problem and has a negative impact on human health and agriculture. Phytoremediation can be an alternative environmental treatment technology, using the natural ability of plants to take up and accumulate pollutants or transform them. Proper development of plants in contaminated areas (e.g. heavy metals) requires them to generate the appropriate protective mechanisms against the toxic effects of these pollutants. This paper presents an overview of the physiological mechanisms of stress avoidance and tolerance by plants used in phytoremediation of heavy metals.

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Authors and Affiliations

Anna Małachowska-Jutsz
Anna Gnida
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Abstract

The work is an attempt to assess piped water quality in four counties located in east central Poland. Piped water was analysed for three successive years in each county. Water samples were tested for the following physical and chemical parameters: turbidity, colour, conductivity, taste, odour, pH, nitrates (III), nitrates (V), iron and manganese. They were compared with the current standard values. Preliminary data analysis included an analysis of maximum and minimum values of physical and chemical parameters, and it revealed that turbidity, colour, iron and manganese contents exceeded the permissible standards in all the counties. Percentages of parameters exceedances and mean values of the exceedances were used to rank the counties in terms of water quality. The ranking was obtained by means of multidimensional comparative analysis. It was demonstrated that best quality water was supplied by Węgrów County water supply system which was followed by Mińsk Mazowiecki County. The third rank was assigned to Łosice County and the poorest quality water was found to be supplied by Siedlce County water supply system.

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Authors and Affiliations

Elżbieta Radzka
Katarzyna Rymuza
Jolanta Jankowska
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Abstract

This study investigates the influence of four imidazolium ionic liquids (ILs) present in wastewater on the activated sludge process. In addition, experiments with inactivated sludge to assess the capacity of this sorbent to remove ILs from the wastewater were conducted. It occurred that the presence of ionic liquids in wastewater reduces biomass growth and size of the sludge flocs. The strongest effect has been found for IL 6 (1-hexyl-2H-3-methyl-4,5-dimethylimidazolium iodide) with the longest alkyl chain length. Also, the degree of ILs removal increases with the alkyl chain length and decreases with the increase of initial concentration of ILs in wastewater. IL 6 reaches the highest degree of ILs removal from wastewater but inhibits the biomass growth and growth of sludge flocs in a greater extent than other tested compounds. Moreover, it was confirmed that newly synthesized ionic liquids can be adsorbed onto inactivated sludge. IL 6 could be adsorbed in a higher degree than other ionic liquids. This adsorption was described by Langmuir isotherm, whereas adsorption of other ionic liquids was described by Freundlich isotherm.

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Authors and Affiliations

Dorota Gendaszewska
Ewa Liwarska-Bizukojć
Cedric Maton
Christian V. Stevens
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Abstract

In this study, solidification/stabilization (S/S) of electric arc furnace dust (EAFD) which is generated during the production of steel from scrap metals and classified as hazardous waste were investigated by using different ratios of cement and low grade MgO (LG MgO) as binding agents. Type I PC 42.5 R portland cement and LG MgO which contains 70–80% MgO were used. S/S blocks that contain different ratios of binding agents which have 1/0.5 – 1/1 – 1/2 – 1/3 – 1/4 – 1/5 cement/LG MgO ratio and S/S blocks which contain only cement and no LG MgO agents were prepared. These blocks, which contain 3 different waste ratios according to weight, 20%, 30% and 40% respectively, were produced and exposed to 28-day water purification. At the end of the purification process, S/S blocks were extracted using TCLP (Toxicity Characteristic Leaching Procedure) tests in order to determine the leaching behavior of Zn, Pb, and Cd in S/S blocks. By the end of this study, it was concluded that the recovery of EAFD is possible and applicable by immobilization. The findings of the study concluded that environmental performances or structural properties of blocks contain 30% waste by weight are suitable. This method is a proper one for recovering and treatment of EAFD with mixture of cement and LG MgO.

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Authors and Affiliations

Ahmet Can Bayraktar
Edip r Avşa
İsmail Toröz
Kadir Alp
Asude Hanedar
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Abstract

The presented paper reports data from malacological and pedological studies carried out at sites representing diverse biotopes (beech wood, coniferous forest, and meadow) located 2 km away from the Dyckerhoff Cement Plant in Sitkówka-Nowiny in 1992 and in 2008–2009. The studies aimed to determine physicochemical properties of soils exposed to cement and limestone dust emission and to identify composition of snail communities inhabiting three different biotopes in relation to physicochemical properties of soils, and to grasp the dynamics of the alkalization-dependent changes in physicochemical properties of soils and their impact on the composition and ecological structure of malacofauna.

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Authors and Affiliations

Jadwiga Anna Barga-Więcławska
Anna Świercz
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Abstract

Sediments of two dam reservoirs in SE Poland, Zalew Zemborzycki (ZZ) and Brody Iłżeckie (BI) were studied. The sediments from both reservoirs were sampled in the transects perpendicular to the shoreline, at the river inflow and the frontal dam. The total concentration of Mn, Zn, Pb, Cd, Cu, Cr and Ni was determined by ICP-EAS method after the sample digestion in the mixture of concentrated HNO3 and HClO4 acids. The statistical analyses: value intervals, mean values, variation coefficient, the median and the skewed distribution were performed. To estimate differences between the means for transects, Tukey’s test was applied with least significant difference (LSD) determination. The maps of the metal spatial distribution were drawn and sediment quality according to the geochemical and ecotoxicological criteria evaluated. Differences between the reservoirs in terms of heavy metals concentration in bottom sediments, and regularities in their spatial distribution were found. In the ZZ sediments the concentration was at the level of geochemical background (Zn, Cr), slightly (Cd, Cu, Ni) or moderately (Pb) contaminated sediments. The metal concentration in the sediments of the BI was up to eight times higher as compared to the ZZ. Moreover, sediments from the BI reservoir showed a greater variability of metal concentration than those from ZZ, which resulted from the dredging operation performed in the part of the reservoir. Metal concentration in sediments of the dredged part was ca. 2–5 times lower than in the undredged one, which indicates that after the dredging operation, accumulation of these metals was slight. The concentrations of Zn, Pb and Cd from the undredged part of BI were at the level of contaminated sediments and exceeded the probable effects level (PEL). In the ZZ, the greatest accumulation of metals occurred in the upper part of the reservoir and at the frontal dam, and the lowest in the middle part of the reservoir. In BI, the lower outflow of water in this reservoir caused a lower metal concentration in the sediments at the frontal dam, as compared with the other sediments in the undredged part of the reservoir. The results indicate that in small and shallow reservoirs, areas of accumulation of heavy metals depend on such factors as a parent river current, reservoir depth, water waving, reservoir shape (narrowing, coves/bays), and type of water outflow.

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Authors and Affiliations

Halina Smal
Sławomir Ligęza
Anna Wójcikowska-Kapusta
Stanisław Baran
Danuta Urban
Radomir Obroślak
Artur Pawłowski

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