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With growing concerns regarding the ecological and human risks of organic micropollutants (OMPs) in water, much effort has been devoted worldwide to establishing quality standards and compiling candidate and watch lists. Although bank filtration is recognized as an efficient natural water treatment in the removal of contaminants such as OMPs, the increase in exploitation requires continuous assessment of removal efficiency. This review aims to provide a critical overview of bank filtration (BF) reports on more than a hundred priority substances (PSs) and compounds of emerging concern (CECs) listed in the relevant European Union regulations. Field- and lab-scale studies analyzing the removal efficiency and its variance of individual OMPs and biological indicators using BF and the main influencing factors and their interactions, shortcomings, and future challenges are discussed in this review. The removal efficiency of EU-relevant contaminants by BF has been comprehensively investigated for only a few pollutants listed in the environmental EU regulations: pharmaceutically active compounds, (e.g., the anti-inflammatory drug diclofenac, some antibiotics (e.g. , sulfamethoxazole and trimethoprim)), a few pesticides (e.g. , atrazine), and faecal indicators such as Escherichia coli. In many cases, the measured concentrations of PSs and CECs have not been published numerically, which hinders comprehensive statistical analysis. Although BF is one of the most cost-effective and efficient water treatments, present field and lab studies have demonstrated the diversity of site-specific factors affecting its efficiency. Even in the case of substances known to be removed by BF, the efficiency rates can vary with environmental and anthropogenic factors (e.g. , hydrogeological parameters and the contamination level of infiltrating water) and abstraction well parameters (e.g. , the depth, distance, and pumping volume). The published removal rate variations and influencing factors often reflect the research design (field or lab-scale), which can lead to ambiguities. [Display omitted] • BF efficiency varies with environmental, anthropogenic, and well properties. • The concomitant influencing factors make the analysis complex. • The methodological heterogeneity in BF studies hinders their comparison. • Removal rate variations often reflect the research design. • Anthropogenic impact on BF efficiency requires further study. [ABSTRACT FROM AUTHOR]

Surface waters are becoming increasingly contaminated by pharmaceutically active compounds (PhACs), which is a potential risk factor for drinking water quality owing to incomplete riverbank filtration. This study examined the efficiency of riverbank filtration with regard to 111 PhACs in a highly urbanized section of the river Danube. One hundred seven samples from the Danube were compared to 90 water samples from relevant drinking water abstraction wells (DWAW) during five sampling periods. The presence of 52 PhACs was detected in the Danube, the quantification of 19 agents in this section of the river was without any precedent, and 10 PhACs were present in >80% of the samples. The most frequent PhACs showed higher concentrations in winter than in summer. In the DWAWs, 32 PhACs were quantified. For the majority of PhACs, the bank filtration efficiency was >95%, and not influenced by concentrations measured in the river. For carbamazepine lidocaine, tramadol, and lamotrigine, low (<50%) filtration efficiency was observed; however, no correlations were observed between the concentrations detected in the Danube and in the wells. These frequently occurring PhACs in surface waters have a relatively even distribution, and their sporadic appearance in wells is a function of both space and time, which may be caused by the constantly changing environment and micro-biological parameters, the dynamic operating schedule of abstraction wells, and the resulting sudden changes in flow rates. Due to the changes in the efficiency of riverbank filtration in space and time, predicting the occurrence and concentrations of these four PhACs poses a further challenge to ensuring a safe drinking water supply. Image 1 • Bank filtration was investigated along a highly urbanized section of the Danube. • Fiftytwo PhACs were detected in the Danube, and 32 were present in drinking water. • Filtration efficiency is not influenced by drug concentrations. • Filtration efficiency for carbamazepine, lamotrigine, lidocaine and tramadol is low. • The concentration of the frequent PhACs changes randomly in operating wells. [ABSTRACT FROM AUTHOR]

The presence and fate of pharmaceutically active compounds (PhACs) in agricultural fields are rarely investigated. The present study highlights that root-derived low-molecular-weight organic acids (LMWOAs) affect the mobility of PhACs in cultivated humic Arenosol. Sorption experiments are conducted using three PhACs characterised by different physicochemical properties: carbamazepine (CBZ), 17α-ethinylestradiol (EE2), and diclofenac-sodium (DFC). The results suggest that the adsorption of EE2 is more intense than the other two PhACs, whereas DFC and CBZ are primarily dominated by desorption. LMWOAs mainly provide additional low-energy adsorption sites for the PhACs, and slight pH changes do not significantly affect the sorption mechanism. During competitive adsorption, the high-energy sites of the adsorbents are initially occupied by EE2 owing to its high adsorption energy (∼15 kJ/mol). The new low-energy binding sites enhance the adsorption of DFC (from 8.5 % to 72.0 %) and CBZ (from 31.0 % to 70.0 %) during multicomponent adsorption. LMWOAs not only affect adsorption by modifying the pH but also provide additional binding sites that allow the PhACs to remain in the root environment for a longer period. As the concentration of LMWOAs temporarily changes, so does the availability of PhACs in the root zone. Environmental changes in the humic horizon enhance the mobility of the adsorbed PhACs, which renders them continuously available for uptake by plants, thus increasing the possibility of PhACs entering the human food chain. [Display omitted] • High-energy sites of the soils were occupied first by 17α-ethinylestradiol (EE2), followed by carbamazepine (CBZ) and diclofenac (DFC). • Low-molecular-weight organic acids (LMWOAs) provided more low-energy adsorption sites for CBZ and DFC. • Statistical analysis shows that organic matter influences the impact of LMWOAs. • The sorption equilibrium of pharmaceuticals varies in time by LMWOAs. [ABSTRACT FROM AUTHOR]

Former state-socialist cities were described by the literature as compact and relatively dense urban forms. However, the political transition of 1989–90 has changed the spatial characteristics of these cities, partly due to urban sprawl. Yet, we do not know if such a phenomenon as "sprawl" did exist before 1989. The main aim of this paper is to assess urban expansion in the metropolitan region of Budapest during state-socialism and after the political changes, and measure the intensity of urban sprawl. The main thesis is that urban sprawl did not start with the advent of market forces in 1989–90, but it was already present during state-socialism, however the tempo of sprawl was considerably increased by suburbanization, the dominant form of urban expansion, after 1990. In order to explore the longitudinal land use changes in the Budapest metropolitan region we analyse standardised databases and maps (e.g. military topographic map from 1959, Corine Land Cover database from 1990 and European Urban Atlas from 2012). The discussion is focused, on the one hand, on the growth of urbanized land as an outcome of urban sprawl and the main underpinning factors in different epochs and, on the other hand, on the main driving forces of suburbanization and sprawl. Research results clearly show that urban sprawl has intensified around Budapest after the political changes. This was the result of a complex interplay of socio-economic and political factors, a process driven by the free movement of residents, firms, as well as the reshuffle of the regulatory framework. The study demonstrates that urban sprawl has several negative impacts on social, economic and environmental sustainability in the investigated metropolitan region, which is in line with findings of the literature. • Despite socialist central planning system urban sprawl around Budapest evolved well before the collapse of sommunism. • Due to suburbanization land conversion and the expansion of artificial surfaces has clearly intensified after the collapse of state socialism. • Urban sprawl was driven by economic factors, changing housing preferences, growing motorization and the reshuffle of the regulatory framework. • Due to urban sprawl the metropolitan region of Budapest became highly hereropolitanized. • Urban sprawl causes various negative socio-economic and environmental consequences and threatens long-term sustainability. [ABSTRACT FROM AUTHOR]

In this paper we present a complex Ecological Footprint (EF) analysis of one of the largest metropolitan regions in post-socialist East Central Europe, the Budapest Metropolitan Region. Our overall goal is to use both top-down and bottom-up approaches and measure the changes of footprint at a metropolitan scale between 2003 and 2013. Our specific objective is to explore how the spatial rearrangements of wealth, density and consumption influence the spatiotemporal changes of EF. The top-down (compound) calculations indicate growing footprint values both in Hungary and in the Budapest Metropolitan Region in the investigated period. However, household-level hybrid (component-based) calculations revealed decreasing footprint values for Hungary both in absolute and relative terms, and a growth for the metropolitan region. This finding suggests growing income disparities within the country. The indirect (consumption embedded) components of EF findings show that in the core city footprint values are higher due to higher disposable income. However, there is a gradual catching up in the suburban zone as younger and more affluent households arrive. On the other hand, direct per capita footprint values decreased in Budapest and grew in the suburbs between 2003 and 2013, mainly due to a higher heating footprint. • Ecological footprint analysis provides a useful tool for measuring the environmental load of urban restructuring • Consumption based EF data confirm an increasing gap between the Budapest urban region and the rest of Hungary • EF values of household consumption grew in Budapest and its agglomeration at similar rates while national values decreased • The growth of EF in Budapest is the result of growing consumption, in the agglomeration the growing footprint of heating • Per capita EF values are similar for Budapest and its agglomeration, however, their compositions differ significantly [ABSTRACT FROM AUTHOR]

A study was conducted on the sorption of 17α-ethynylestradiol (EE2) on five soils formed under different redox conditions: an Arenosol (A_20) with fully aerobic conditions, two Gleysol samples (G_20 and G_40) with suboxic and anoxic conditions and two Histosols (H_20 and H_80) with mostly anoxic conditions. The soils were characterized on the basis of total organic carbon (TOC), specific surface area (SSA) and the Fourier transform infrared spectra of the humic acid and humin fractions (the soil remaining after alkali extraction) of the soil. The maximum adsorption capacity of the soils (Q max) ranged from 10.7 to 83.6 mg/g in the order G_20 > H_20 > G_40 > A_20 > H_80, which reflected the organic matter content of the soils. The sorption isotherms were found to be nonlinear for all the soil samples, with Freundlich n values of 0.45–0.68. The strong nonlinearity found in the adsorption of the H_80 samples could be attributed to their high hard carbon content, which was confirmed by the high aromaticity of the humin fraction. The maximum sorption capacity (Q max) of the soils did not increase indefinitely as the organic carbon content of the soils rose. There could be two reasons for this: (i) the large amount of organic matter may reduce the number of binding sites on the surface, and (ii) the decrease in SSA with increasing soil OC content may limit the ability to adsorb EE2 molecules. In anaerobic soil samples, where organic matter accumulation is pronounced, the amount of aromatic and phenolic compounds was higher than in better aerated soil profiles. Strong correlations were found between the amount of aromatic and phenolic compounds in the organic matter and the adsorption of EE2 molecules, indicating that π-π interaction and H-bonding are the dominant sorption mechanisms. Image 10063 • The adsorption of EE2 was connected with the redox potential of the soils. • Aromatic and phenolic compounds were found to be abundant in anaerobic layers. • Hydromorphic soils with organic matter accumulation had high adsorption capacity. • π-π interaction and H-bonding were found the dominant sorption mechanisms. [ABSTRACT FROM AUTHOR]