The aim of this study was to improve our understanding of metal bioavailability in soil by linking the biotic ligand approach with toxicokinetics modelling. We determined cadmium bioaccumulation kinetics in Folsomia candida (Collembola) as a function of soil pH. Animals were exposed for 21 days to LUFA 2.2 soil at 5 or 20 μg Cd g−1 dry soil followed by 21 days elimination in clean soil. Internal cadmium concentrations were modelled using a first-order one-compartment model, relating uptake rate constants (k1) to total soil, water or 0.01 M CaCl2 extractable and porewater concentrations. Based on total soil concentrations, k1 was independent of soil pH while it strongly increased with increasing pH based on porewater concentrations explaining the reduced competition of H+ ions making cadmium more bioavailable in pore water at high pH. This shows that the principles of biotic ligand modelling are applicable to predict cadmium accumulation kinetics in soil-living invertebrates.

It is generally accepted that urban vegetation improves air quality and thereby enhances the well-being of citizens. However, empirical evidence on the potential of urban trees to mitigate air pollution is meager, particularly in northern climates with a short growing season. We studied the ability of urban park/forest vegetation to remove air pollutants (NO2, anthropogenic VOCs and particle deposition) using passive samplers in two Finnish cities. Concentrations of each pollutant in August (summer; leaf-period) and March (winter, leaf-free period) were slightly but often insignificantly lower under tree canopies than in adjacent open areas, suggesting that the role of foliage in removing air pollutants is insignificant. Furthermore, vegetation-related environmental variables (canopy closure, number and size of trees, density of understorey vegetation) did not explain the variation in pollution concentrations. Our results suggest that the ability of urban vegetation to remove air pollutants is minor in northern climates.

Biospectroscopy is an emerging inter-disciplinary field that exploits the application of sensor technologies [e.g., Fourier-transform infrared spectroscopy, Raman spectroscopy] to lend novel insights into biological questions. Methods involved are relatively non-destructive so samples can subsequently be analysed by more conventional approaches, facilitating deeper mechanistic insights. Fingerprint spectra are derived and these consist of wavenumber–absorbance intensities; within a typical biological experiment, a complex dataset is quickly generated. Biological samples range from biofluids to cytology to tissues derived from human or sentinel sources, and analyses can be carried out ex vivo or in situ in living tissue. A reference range of a designated normal state can be derived; anything outside this is potentially atypical and discriminating chemical entities identified. Computational approaches allow one to minimize within-category confounding factors. Because of ease of sample preparation, low-cost and high-throughput capability, biospectroscopy approaches herald a new greener means of environmental health monitoring in urban environments.

The influence of biochar (5%) on the loss, partitioning and bioaccessibility of 14C-isoproturon (14C-IPU) was evaluated. Results indicated that biochar had a dramatic effect upon 14C-IPU partitioning: 14C-IPU extractability (0.01 M CaCl2) in biochar-amended treatments was reduced to <2% while, 14C-IPU extractability in biochar free treatments decreased with ageing from 90% to 40%. A partitioning model was constructed to derive an effective partition coefficient for biochar:water (KBW of 7.82 × 104 L kg−1). This was two orders of magnitude greater than the apparent Kfoc value of the soil organic carbon:water (631 L kg−1). 14C-radiorespirometry assays indicated high competence of microorganisms to mineralise 14C-IPU in the absence of biochar (40.3 ± 0.9%). Where biochar was present 14C-IPU mineralisation never exceeded 2%. These results indicate reduced herbicide bioaccessibility. Increasing IPU application to ×10 its recommended dose was ineffective at redressing IPU sequestration and its low bioaccessibility.

To understand the role of abundance of tfdA gene classes belonging to β- and γ-proteobacteria on phenoxy acid herbicide degradation, streambed sediments were sampled around three seepage meters (SMs) installed in a landfill-impacted groundwater–surface water interface. Highest herbicide mass discharge to SM3, and lower herbicide mass discharges to SM1 and SM2 were determined due to groundwater discharge rates and herbicide concentrations. SM1-sediment with the lowest abundance of tfdA gene classes had the slowest mineralization, whereas SM2- and SM3-sediments with more abundant tfdA genes had faster mineralization. The observed difference in mineralization rates between discharge zones was simulated by a Monod-based kinetic model, which confirmed the role of abundance of tfdA gene classes. This study suggests presence of specific degraders adapted to slow growth rate and high yield strategy due to long-term herbicide exposure; and thus groundwater–surface water interface could act as a natural biological filter and protect stream water quality.

In this work, a recently developed urban-scale atmospheric dispersion model (DAUMOD-GRS) is applied to evaluate the ground-level ozone (O3) concentrations resulting from anthropogenic area sources of NOx and VOC in the Metropolitan Area of Buenos Aires (MABA). The statistical comparison of model results with observations (including new available data from seventeen sites) shows a good model performance. Estimated summer highest diurnal O3 1-h concentrations in the MABA vary between 15 ppb in the most urbanised area and 53 ppb in the suburbs. All values are below the air quality standard. Several runs are performed to evaluate the impact of possible future emission reductions on O3 concentrations. Under all hypothetical scenarios, the maximum diurnal O3 1-h concentration obtained for the area is slightly reduced (up to 4%). However, maximum diurnal O3 concentrations could increase at some less urbanised areas of MABA depending on the relative reductions of the emissions of NOx and VOC.

A submerged membrane bioreactor has been operated at the laboratory scale for the treatment of a synthetic effluent containing Bisphenol-A (BPA). COD, NH4–N, PO4–P and BPA were eliminated respectively, at 99%, 99%, 61% and 99%. The increase of volumetric loading rate from 0 to 21.6 g/m3/d did not affect the performance of the MBR system. However, the removal rate decreased rapidly when the BPA loading rate increased above 21.6 g/m3/d. The adsorption process of BPA on the biomass was very well described by Freundlich and Langmuir isotherms. Subsequently, biodegradation of BPA occurred and followed the first order kinetic reaction, with a constant rate of 1.13 ± 0.22 h−1. During treatment, membrane fouling was reversible in the first 84 h of filtration, and then became irreversible. The membrane fouling was mainly due to the accumulation of suspended solid and development of biofilm on the membrane surface.

Trees can improve air quality by capturing particles in their foliage. We determined the particle capture efficiencies of coniferous Pinus sylvestris and three broadleaved species: Betula pendula, Betula pubescens and Tilia vulgaris in a wind tunnel using NaCl particles. The importance of leaf surface structure, physiology and moderate soil drought on the particle capture efficiencies of the trees were determined. The results confirm earlier findings of more efficient particle capture by conifers compared to broadleaved plants. The particle capture efficiency of P. sylvestris (0.21%) was significantly higher than those of B. pubescens, T. vulgaris and B. pendula (0.083%, 0.047%, 0.043%, respectively). The small leaf size of P. sylvestris was the major characteristic that increased particle capture. Among the broadleaved species, low leaf wettability, low stomatal density and leaf hairiness increased particle capture. Moderate soil drought tended to increase particle capture efficiency of P. sylvestris.

Zlatna, Romania is the site of longtime mining/smelting operations which have resulted in widespread metal pollution of the entire area. Previous studies have documented the contamination using traditional methods involving soil sample collection, digestion, and quantification via inductively coupled plasma atomic emission spectroscopy or atomic absorption. However, field portable X-ray fluorescence spectroscopy (PXRF) can accurately quantify contamination in-situ, in seconds. A PXRF spectrometer was used to scan 69 soil samples in Zlatna across multiple land use types. Each site was georeferenced with data inputted into a geographic information system for high resolution spatial interpolations. These models were laid over contemporary aerial imagery to evaluate the extent of pollution on an individual elemental basis. Pb, As, Co, Cu, and Cd exceeded governmental action limits in >50% of the sites scanned. The use of georeferenced PXRF data offers a powerful new tool for in-situ assessment of contaminated soils.

Living in an urban environment is associated with an increased prevalence of specific mental health disorders, particularly schizophrenia. While many factors have been discussed as possible mediators of this association, most researchers favour the hypothesis that urban living stands as a proxy for an increased exposure to social stress. This factor has been recognized as one of the most powerful causes for the development of mental disorders, and appears to correlate with the markedly increased incidence of schizophrenia in urban minority groups. However, the hypothesis that the general urban population is exposed to increased levels of social stress has to be validated. Pursuing the goal of understanding how social stress acts as a risk factor for mental disorder in urban populations must include factors like social conditions, environmental pollutants, infrastructure and economic issues.