It was previously shown that arbuscular mycorrhizal fungi (AMF) exert a significant improvement of growth in a tolerant white poplar (Populus alba L.) clone (AL35) grown on Cu- and Zn-polluted soil via foliar alterations in the levels of defence/stress-related transcripts and molecules. However, nothing is known about the epigenetic changes which occur during tolerance acquisition in response to heavy metals (HMs) in the same mycorrhizal vs. non-mycorrhizal poplar plants. In order to analyse the epigenome in leaves of AL35 plants inoculated or not with AMF and grown in a greenhouse on multimetal polluted or unpolluted soil, the Methylation Sensitive Amplification Polymorphism (MSAP) approach was adopted to detect cytosine DNA methylation. Modest changes in cytosine methylation patterns were detected at first sampling (4 months from planting), whereas extensive alterations (hypomethylation) occurred at second sampling (after 6 months) in mycorrhizal plants grown in the presence of HMs. The sequencing of MSAP fragments led to the identification of genes belonging to several Gene Ontology categories. Seven MSAP fragments, selected on the basis of DNA methylation status in treated vs control AL35 leaves at the end of the experiment, were analysed for their transcript levels by means of qRT-PCR. Gene expression varied in treated samples relative to controls in response to HMs and/or AMF inoculation; in particular, transcripts of genes involved in RNA processing, cell wall and amino acid metabolism were upregulated in the presence of AMF with or without HMs.

The Mediterranean basin, because of its semi-enclosed configuration, is one of the areas heavily affected by air pollutants. Despite implications on both human health and radiative budget involving an increasing interest, monitoring databases measuring air pollution directly over this area are yet relatively limited. Owing to this context, concentrations of fine (PM₂.₅) and coarse (PM₂.₅–₁₀) particles along with other ancillary data, such as ozone levels and meteorological parameters, were measured during six cruise campaigns covering almost the whole Mediterranean basin. Elemental composition of both PM₂.₅and PM₂.₅–₁₀was also determined to identify specific tracers for different classes of particles that can be found in the Mediterranean atmosphere. Outcomes resulting from the integration of a preliminary qualitative examination with a more quantitative analysis, based on receptor modelling, suggested that European continental influence, Saharan dust outbreaks, wildfire events, sea spray and fossil fuel combustion were the leading causes of the aerosol-ozone variations within the Mediterranean basin. Shipping emissions, consisting in both local harbours and maritime traffic across the basin, were also tested using the marker ratio of V/Ni. Peak values observed for coarse fraction have shown to be driven by the occurrence of African dust events. Considering the major influence of Continental pollution and wildfire events, the spatial variability resulted in larger fine particle concentrations and higher ozone levels over the Eastern Mediterranean side in comparison to the Western one.

New Caledonia is one of the main hot spots of biodiversity on the planet. Large amounts of contaminants are discharged into the lagoon as a result of increasing anthropogenic activities such as intense mining, urbanization, and industrialization. Concentrations of 14 trace elements and 26 persistent organic pollutants (POPs: PCBs and pesticides) were measured in the muscles of two anguilliform fish species, over a coast to barrier reef gradient in two lagoon areas differently exposed to anthropic disturbances. This study emphasizes the high trace element contamination status of anguilliform fish and also highlights slight but perceptible organic pollution. The contamination extends throughout the lagoon, from coast to barrier reef, even in areas remote from emission points. High levels of trace elements, especially those linked to mining activities (i.e., Co, Cr, Fe, Mn, and Ni), were detected in coastal sites. Furthermore, the large dispersion of most POPs throughout the entire lagoon poses the question of their potential toxicity on marine organisms from numerous habitats. Our results underline the need for long-term monitoring of various contaminants over large spatial and time scales.

Chemical Leasing is a service-oriented business model that shifts the focus from increasing sales volume of chemicals towards a value-added approach. Recent pilot projects have shown the economic benefits of introducing Chemical Leasing business models in a broad range of sectors. A decade after its introduction, the promotion of Chemical Leasing is still predominantly done by the public sector and international organizations. We show in this paper that awareness-raising activities to disseminate information on this innovative business model mainly focus on the economic benefits. We argue that selling Chemical Leasing business models solely on the grounds of economic and ecological considerations falls short of branding it as a corporate social responsibility initiative, which, for this paper, is defined as a stakeholder-oriented concept that extends beyond the organization’s boundaries and is driven by an ethical understanding of the organization’s responsibility for the impact of its business activities. For the analysis of Chemical Leasing business models, we introduce two case studies from the water purification and metal degreasing fields, focusing on employees and local communities as two specific stakeholder groups of the company introducing Chemical Leasing. The paper seeks to demonstrate that Chemical Leasing business models can be branded as a corporate social responsibility initiative by outlining the vast potential of Chemical Leasing to improve occupational health and safety and to strengthen the ability of companies to protect the environment from the adverse effects of the chemicals they apply.

A novel method for the extraction of Sudan dyes including Sudan I, II, III, and IV from environmental water by magnetic titanium dioxide nanoparticles (Fe₃O₄@TiO₂) coated with sodium dodecylsulfate (SDS) as adsorbent was reported. Fe₃O₄@TiO₂ was synthesized by a simple method and was characterized by transmission electron microscopy, Fourier-transform infrared spectrometry, and vibrating sample magnetometer. The magnetic separation was quite efficient for the adsorption and desorption of Sudan dyes. The effect of the amount of SDS, extraction time, pH, desorption condition, maximal extraction volume, and humic acid on the extraction process were investigated. This method was employed to analyze three environmental water samples. The results demonstrated that our proposed method had wide linear range (25–5,000 ng L⁻¹) with a good linearity (R ² > 0.999) and low detection limits (2.9–7.3 ng L⁻¹). An enrichment factor of 1,000 was achieved. In all three spiked levels (25, 250, and 2,500 ng L⁻¹), the recoveries of Sudan dyes were in the range of 86.9–93.6 %. The relative standard deviations obtained were ranging from 2.5 to 9.3 %. That is to say, the new method was fast and effective for the extraction of Sudan dye from environmental water.

In the current study, the bioaccumulation of essential and nonessential metals and related antioxidant activity were analyzed in three organs (muscle, gills, and liver) of herbivorous (HF) and carnivorous (CF) edible fish of Chenab River. The comparative analysis revealed a more heterogeneous accumulation of metals in the muscles of HF fish than that of CF fish [chromium (Cr, 3.4 μg g⁻¹), cobalt (Co, 1.7 μg g⁻¹), copper (Cu, 3 μg g⁻¹), and iron (Fe, 45 μg g⁻¹) versus Cr (1.3 μg g⁻¹), Co (0.1 μg g⁻¹), Cu (1.1 μg g⁻¹), and Fe (33 μg g⁻¹), respectively, P < 0.001]. These results implied an organ-specific accumulation of metals at different trophic levels. According to logistic regression analysis, the bioaccumulation of metals had marked differences in HF and CF. The antioxidant activity was significantly related to the tissue type and the metals to which the organs are exposed to. The liver of CF fish had a higher activity of antioxidant superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and lipid peroxidase (LPO) than that of HF (P < 0.05). LPO and guaiacol peroxidase (POD) in both groups were associated with a number of metals, but in HF, cadmium (Cd), Cr, Pb, and Zn were more related with the LPO and SOD activities. Moreover, Cd, Co, Fe, Pb, Ni, Cu, and Zn were above the permissible limits set by various agencies. In numerous cases, our results were even higher than those previously reported in the literature. The results provide an insight into the pollution pattern of Chenab River. These results may be helpful in the future to identify biomarkers of exposure in aquatic organisms.

Self-cleaning photocatalytic coatings for biocalcarenite stones, based on TiO₂nanoparticles obtained by sol–gel processes at different pH values and also adding gold particles, have been investigated. The selected test material is a biocalcarenite named “pietra di Lecce” (Lecce stone), outcropping in Southern Italy. Scanning electron microscopy with energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, and Raman investigations were carried out to characterize the TiO₂nanoparticles and coatings. Nanocrystalline anatase and, to a lesser extent, brookite phases are obtained. Photocatalytic activity of the TiO₂sols and of the coatings on “pietra di Lecce” was assessed under ultraviolet irradiation, monitoring methyl orange (MeO) dye degradation as a function of time. To evaluate the harmlessness of the treatment, colorimetric tests and water absorption by capillarity were performed. The results show good photodegradation rates for titania nanosols, particularly when putting in Au particles, whereas a satisfactory chromatic compatibility between the sol and the surface of the calcarenite is found only without Au addition. HIGHLIGHTS: Sols of nanocrystalline titania at different pH values and with Au particles were prepared and characterized. Satisfactory photodegradation of MeO by the sols in solution and on calcarenite-coated surfaces is obtained. The addition of Au particles improves the photodegradation activity but gives poor chromatic results on “pietra di Lecce”.

Spectral confocal microscope visualizations of microsphere movement in unsaturated porous media showed that attachment at the Air Water Solid (AWS) interface was an important retention mechanism. These visualizations can aid in resolving the functional form of retention rates of colloids at the AWS interface. In this study, soil adsorption isotherm equations were adapted by replacing the chemical concentration in the water as independent variable by the cumulative colloids passing by. In order of increasing number of fitted parameters, the functions tested were the Langmuir adsorption isotherm, the Logistic distribution, and the Weibull distribution. The functions were fitted against colloid concentrations obtained from time series of images acquired with a spectral confocal microscope for three experiments performed where either plain or carboxylated polystyrene latex microspheres were pulsed in a small flow chamber filled with cleaned quartz sand. Both moving and retained colloids were quantified over time. In fitting the models to the data, the agreement improved with increasing number of model parameters. The Weibull distribution gave overall the best fit. The logistic distribution did not fit the initial retention of microspheres well but otherwise the fit was good. The Langmuir isotherm only fitted the longest time series well. The results can be explained that initially when colloids are first introduced the rate of retention is low. Once colloids are at the AWS interface they act as anchor point for other colloids to attach and thereby increasing the retention rate as clusters form. Once the available attachment sites diminish, the retention rate decreases.

The purpose of this study is to examine tissue patterns of metal (Cr, Ni, Cu, Cd, and Pb) concentrations in Solanum melongena cultivated in close proximity to traffic to help elucidate associated elemental deposition and soil-to-root and root-to-shoot transfers. Plants were cultivated in a commercial soil mix at three sites in Toronto, Canada. Metal concentrations were determined on microwave-digested bulk and rhizosphere soil and tissue samples per ICP-MS, along with two standard reference materials (NIST #1570a and #2709a). Unwashed and washed S. melongena samples were also analyzed, along with Origanum vulgare plants from the same sites, to assess the effectiveness of washing in reducing metal concentrations. The tissue distribution of Cr, Ni, Cu, and Pb demonstrated variability as a function of traffic proximity. Copper was found to easily translocate to roots in soils susceptible to waterlogging, while Cd had the highest soil-to-root and root-to-shoot translocation. The translocation of Cd was highest at the roadside site, due to a greater relative enrichment of this metal in the rhizosphere of S. melongena plants. Washing O. vulgare leaves was more effective in removing metal-associated particles compared to S. melongena samples. Cadmium uptake is of greatest concern given its toxicity and translocation potential.

The extracellular polymeric substance (EPS) extracted from waste activated sludge (WAS) after short-time aerobic digestion was investigated to be used as a novel biosorbent for Cu²⁺removal from water. The EPS consisted of protein (52.6 %, w/w), polysaccharide (30.7 %, w/w), and nucleic acid (16.7 %, w/w). Short-time aerobic digestion process of WAS for about 4 h promoted the productivity growth of the EPS for about 10 %. With a molecular weight of about 1.9 × 10⁶ Da, the EPS showed a linear structure with long chains, and contained carboxyl, hydroxyl, and amino groups. The sorption kinetics was well fit for the pseudo-second-order model, and the maximum sorption capacity of the EPS (700.3 mg Cu²⁺/g EPS) was markedly greater than those of the reported biosorbents. Both Langmuir model and Freundlich model commendably described the sorption isotherm. The Gibbs free energy analysis of the adsorption showed that the sorption process was feasible and spontaneous. According to the complex results of multiple analytical techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, atomic force microscopy, etc., the adsorption process took place via both physical and chemical sorption, but the electrostatic interaction between sorption sites with the functional groups and Cu²⁺is the major mechanism.