Textile industry is responsible for a large amount of polluted water released daily, mainly due to the dyes used. This article has aimed to study and improve methodologies for degrading textile effluents containing the dyes Acid Red 151 and Acid Blue 40 using an electrolytic reactor. Different solutions were prepared for the experiments in the electrolytic reactor with a 70 % TiO₂/30 % RuO₂anode. The textile effluents underwent 0 (control), 3, and 30 min treatment intervals. A suspension of Saccharomyces cerevisiae cells was used for toxicity tests and performed at the same day that samples were collected. The same test was applied to the samples after 15 days resting in order to verify changes in toxicity. The electrolytic treatment successfully removed the color in all effluents. However, the process efficiency varies according to the dye used and the experimental conditions, such as current and NaCl concentration. Also, it was observed that treatments longer than 30 min are very toxic to S. cerevisiae cells because of the high concentration of Cl₂.

From April 2006 to April 2007, the geographical and seasonal variation in nitrogen content in terricolous lichen (Cladonia portentosa) and atmospheric ammonia concentrations were measured at five heathland sites. The seasonal variation in the nitrogen content of the lichen was small, even though there was a large seasonal variation in the air concentration of ammonia. A sizable local variation in the nitrogen content of the lichen was found even at the scale of a few kilometres. The nitrogen content in the lichen showed a high correlation to the yearly mean value of the measured ammonia concentration in air at the different locations. This investigation is part of a larger attempt to incorporate effects of nitrogen in the conservation status of terrestrial habitat types.

Microorganisms are abundant in many surface and near-surface geochemical environments. They interact with arsenic through a variety of mechanisms, including sorption, mobilisation, precipitation and redox and methylation transformation; sometimes, this is to their benefit, while other times it is to their detriment, substantially affecting the fate and transport of arsenic in the environment. Here, an attempt was made to review the current state of knowledge concerning microbial influences on arsenic transformation and retention processes at the water–solid interface with the goal to elucidate the ability of microorganisms to react with arsenic, and to quantify the role of microorganisms in the biogeochemical arsenic cycle. Such knowledge is indispensable for comprehensive understanding arsenic behaviour in the environment and support accurate assessment of the threat of arsenic contamination to human and environmental health, as well as for the development of novel technologies for arsenic bioremediation.

Magnetic 0.8Ni₀.₅Zn₀.₅Fe₂O₄/0.2SiO₂ nanocomposites were prepared by the facile citrate-gel thermal decomposition process. Their microstructure and magnetic properties were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), and vibrating sample magnetometer (VSM). The as-prepared magnetic 0.8Ni₀.₅Zn₀.₅Fe₂O₄/0.2SiO₂ nanocomposites were characterized with about 8-nm grains, specific surface area of 119.3 m²/g, and magnetization of 38.7 Am²/kg. The adsorption kinetics and adsorption isotherms of methyl blue (MB) and As(V) onto the magnetic 0.8Ni₀.₅Zn₀.₅Fe₂O₄/0.2SiO₂ nanocomposites at room temperature were investigated. Adsorption kinetics of MB and As(V) onto the magnetic 0.8Ni₀.₅Zn₀.₅Fe₂O₄/0.2SiO₂ nanocomposites have been researched using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, the statistic results show that the pseudo-second-order kinetic model is fitted well to describe the MB and As(V) adsorption process. The adsorption equilibrium data of MB and As(V) onto the magnetic 0.8Ni₀.₅Zn₀.₅Fe₂O₄/0.2SiO₂ nanocomposites at room temperature were analyzed with Langmuir, Freundlich, and Temkin models, and the adsorption isotherms was more effectively described by the Freundlich model based on the values of the correlation coefficient. Figure The magnetic 0.8Ni₀.₅Zn₀.₅Fe₂O₄/0.2SiO₂ nanocomposites were prepared by the citrate-gel thermal decomposition process. They show high adsorption capacities for methyl blue (MB) and arsenic(V) in aqueous solution, and the adsorption kinetics and isothermals were analyzed.

The variability of levels of fecal indicator bacteria (FIB) and a human-associated genetic marker (HF183) during wet and dry weather conditions was investigated at two urban coastal watersheds in Southern California: Santa Monica Canyon channel (SMC) and Ventura Harbor, Keys, and Marina. Seventy-eight to 86 % of the samples collected from SMC sites exceeded standard water quality standards for FIB (n = 59 to 76). At SMC, HF183 was present in 58 % of the samples (n = 78) and was detected at least once at every sample site. No individual site at SMC appeared as a hotspot for the measured indicators, pointing to a likely chronic issue stemming from urban runoff in wet and dry weather. In Ventura, the Arundell Barranca, which drains into Ventura Harbor and Marina, was a source of FIB, and HF183 was most frequently detected off of a dock in the Marina. Rainfall significantly increased FIB levels at both SMC and Ventura; only at Ventura did HF183 detection increase with wet weather. Sample locations that were high in FIB were geographically distinct from the sites that were high in HF183 in Ventura, which supports the importance of measuring host-associated parameters along with FIB in chronically impaired watersheds to guide water quality managers in pollution remediation efforts.

A novel high-capacity phosphate removal adsorbent of graphene nanosheets (GNS) supported lanthanum hydroxide (LaOH) is prepared. The phosphate adsorption performance for GNS-LaOH is examined by a batch adsorption method from aqueous solutions. The Freundlich and Langmuir models are used to simulate the sorption equilibrium, which reveal that the Langmuir model has a better correlation with the experimental data. The maximum adsorption capacity is calculated to be 41.96 mg/g. The kinetic data from the adsorption of phosphate is suggested as the pseudo-second-order model, and the multi-linearity adsorption process is observed in the intraparticle diffusion model, indicating that a chemisorption process is dominant in the adsorption of phosphate. The phosphate adsorption mechanism is explored by analyzing the Fourier transform infrared spectroscopy (FT-IR) and the relationship between the adsorption amount and the pH value of phosphate solution. Ligand exchange and electrostatic and Lewis acid–base interactions are determined to be three main factors for phosphate adsorption.

The main purpose of this study was to evaluate the mercury (Hg) bioaccumulation in the Egyptian mongoose (Herpestes ichneumon), a terrestrial predator species with an essential role in the Iberian ecosystems food chain. Differences between males and females and the effect of age in mercury body burdens were studied, as well as the geographical distribution of mercury in tissues of the studied species. Total mercury (T-Hg) was determined in muscle, liver, lungs, heart, spleen, kidneys, blood, brain, fat and pelage of the Egyptian mongoose from 14 locations, encompassing the distribution range of the element in the species. In order to study differences between ages, males and females, 20 individuals from one sampling location were analysed. Total mercury concentrations ranged between 0.01 and 13 μg g⁻¹(dry weight (dw)) and followed the order from the least to the most contaminated: fat < brain < lungs < heart < spleen < muscle < kidneys < liver < pelage < blood. Differences between males and females were only significant for muscle and pelage mercury levels, suggesting uptake rates and metabolic processes to be similar between genders. Despite a similar accumulation pattern with age between males and females, differences between ages were significant only for females, as a result of a higher range of male mercury body burdens. Organic mercury (O-Hg) was analysed in muscle and liver, and its percentage ranged from 83 to 96 %, reflecting the high trophic level of the species. None of the observed mercury levels reached the lethal or toxic values established for terrestrial predators (20 to 100 μg g⁻¹wet weight), suggesting that despite its predatory position in terrestrial food webs, the risk of mercury associated toxicity is low.

The degradation ability of newly isolated bacterial strain Ochrobactrum anthropi toward polychlorinated biphenyls (PCBs) was examined under aerobic conditions. The strain was isolated from historically PCB-contaminated sediments from Strážsky canal in eastern Slovakia, surrounding of the former PCB producer. The degradation ability of the strain was enhanced by addition of other substrates and degradation inducers—biphenyl, glucose, both biphenyl and glucose, ivy leaves, and pine needles. The adaptation of cells membrane toward PCBs in the presence of abovementioned substrates was evaluated with the changes in fatty acid composition (membrane saturation, cis–trans isomerization, and changes in branched fatty acids synthesis). The highest induction of PCB degradation and lowest cell adaptation in liquid medium was achieved using ivy leaves. On the other hand, lowest degradation was achieved when PCBs were added alone. Similar low degradation was observed in the presence of glucose addition together with biphenyl. Contrary, highest growth stimulation under the applied condition was observed. Obtained results indicated that addition of glucose together with biphenyl induced PCB degradation via bacterial growth stimulation, not via the induction of activity of degradation enzymes. Cut ivy leaves (containing terpenoic compounds serving as degradation inducer and structural analog of biphenyl) increased PCB removal from contaminated sediment by O. anthropi. Results indicate the degradation ability of O. anthropi toward penta-, hexa-, and hepta-chlorinated PCB congeners. The degradation of congeners with more than five chlorine atoms per molecule was detected in higher extent compared to dichlorinated congeners.

The synthesis, characterization, and photocatalytic evaluation of titania-loaded MCM-41 with and without Au doping are reported in the present study. The samples were characterized by powder XRD, TEM, low temperature N₂adsorption/desorption, UV–Vis, and FTIR. UV-induced vapor-phase photo-oxidation of acetone was used as a probe reaction to study the role of Au in mineralization of volatile organic compounds (VOCs), viz. acetone at different concentrations. The doping of Au in titania-loaded MCM-41 resulted in the decrease of BET surface area, total pore volume, and average pore size. UV–Vis diffuse reflectance spectra of Au-doped titania-loaded MCM-41 showed the red shift in their absorption bands compared to titania-loaded MCM-41. The activity of mineralization of acetone by photocatalysis for 2 % Au-doped titania-loaded MCM-41 was found to be ∼1.6 times higher than titania-loaded MCM-41. The presence of cocatalytic nanosized gold might be responsible for their enhanced activity on account of the delayed recombination of electron/hole pair. Although, almost complete mineralization of acetone was observed irrespective of the initial concentration of acetone in air (up to 3.72 mol%) by all the catalysts, 2 wt.% Au-doped titania-loaded MCM-41 has shown the most enhanced activity.

In this study, we simulated heterotrophic CO₂(Rh) fluxes at six European peatland sites using the ECOSSE model and compared them to estimates of Rh made from eddy covariance (EC) measurements. The sites are spread over four countries with different climates, vegetation and management. Annual Rh from the different sites ranged from 110 to 540 g C m⁻². The maximum annual Rh occurred when the water table (WT) level was between −10 and −25 cm and the air temperature was above 6.2 °C. The model successfully simulated seasonal trends for the majority of the sites. Regression relationships (r²) between the EC-derived and simulated Rh ranged from 0.28 to 0.76, and the root mean square error and relative error were small, revealing an acceptable fit. The overall relative deviation value between annual EC-derived and simulated Rh was small (−1 %) and model efficiency ranges across sites from −0.25 to +0.41. Sensitivity analysis highlighted that increasing temperature, decreasing precipitation and lowering WT depth could significantly increase Rh from soils. Thus, management which lowers the WT could significantly increase anthropogenic CO₂, so from a carbon emissions perspective, it should be avoided. The results presented here demonstrate a robust basis for further application of the ECOSSE model to assess the impacts of future land management interventions on peatland carbon emissions and to help guide best practice land management decisions.