This study examined the impact of oxidative stress indicated by thiobarbituric acid reactive substances (TBARS) and protein carbonyl (PC), induced by intensive exercise and cadmium chloride (CdCl₂) on ethoxyresorufin-O-deethylase (EROD) activity in juvenile carp (Cyprinus carpio). In the first experiment, fish were divided into three groups: (1) control, (2) carp exposed to intensive exercise, and (3) carp that was not exercised but previously, as well as carp in group 2, received single dose of 3-methylcholantrene (3-MC). The third and sixth day fish were sacrificed and the measurements were conducted. In the second experiment, fish were divided into (1) control, (2) carp in water containing CdCl₂, and (3) carp in dechlorinated tap water (2 and 3 received single dose of 3-MC on the seventh day after exposure to CdCl₂). The carp were killed 6 days later and livers were excised for biochemical analyses. In the first experiment, on the sixth day after treatment with 3-MC, results show statistically significant increase in EROD activity in non-exercised carp, while that increase in carp exposed to intensive exercise was significantly lower. Three days after exposure to 3-MC, statistically significant increase in TBARS was observed in both exercised and non-exercised carp. Six days after exposure to 3-MC, PC levels were significantly higher in exercised carp. Pretreatment with CdCl₂, in the second experiment, caused oxidative stress and reduction of EROD activity. Results show linkage between expression of EROD activity and oxidative stress biomarkers and possible influence of oxidative stress on the cell membrane structures and consequently on EROD activity.

In this study, the applications of mesoporous materials based on silica, and those with modifications, namely post-synthetic grafting, co-condensation, and pure SBA-15, were investigated for the removal of phosphate from sewage. The mesostructures were confirmed by X-ray diffraction, Brunauer–Emmett–Teller, Fourier transform infrared spectroscopy, and transmission electron microscopy. The absorption of phosphate by the mesoporous adsorbents was examined, using different adsorption models to describe the equilibrium and kinetic data. The maximum adsorption capacities of the mesostructured adsorbents were found to be 69.970, 59.890, and 2.018 mg/g for the co-condensation, post-synthetic grafting, and pure SBA-15, respectively. The kinetic data showed that the adsorption of phosphate onto three different mesostructures followed the pseudo-first-order kinetic model.

Paracetamol is an antipyretic analgesic widely used globally. It has been recurrently found in water bodies and is known to elicit toxic effects in aquatic species; however, its potential ability to induce oxidative stress in sentinel species remains unknown The objective was to establish a methodology to evaluate the toxicity elicited on the sentinel species Hyalella azteca by paracetamol-enriched sediment using oxidative stress tests. Concentrations used in assays were determined using the previously obtained median lethal concentration (72 h LC₅₀). The following oxidative stress biomarkers were evaluated: lipid peroxidation (LPO), protein carbonyl content (PCC) in order to determine oxidized protein content, and the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX). LPO and PCC increased significantly while SOD, CAT, and GPX decreased significantly (p < 0.05) with respect to controls. Paracetamol induces oxidative stress on H. azteca, and the set of tests employed is helpful in evaluating the toxicity of this group of pharmaceuticals on aquatic species.

The aim of the study was to determine whether the application of superphosphate fertiliser to soils contaminated with mine wastes can inhibit metal and metalloid mobility (Cu, Pb, Zn, Cd, Fe, Mn, As, Sb) in the long term. Contaminated soils contained sulfide- and sulfate-rich waste materials from the Broken Hill and Mt Isa mining centres. Results of long-term (10 months) column experiments demonstrate that fertiliser amendment had highly variable effects on the degree of metal and metalloid mobilisation and capture. Rapid release of metals from a sulfate-rich soil showed that phosphate amendment was ineffective in stabilising highly soluble metal-bearing phases. In a sulfide-rich soil with abundant organic matter, complexing of metals with soluble organic acids led to pronounced metal (mainly Cd, Cu and Zn) release from fertiliser-amended soils. The abundance of pyrite, as well as the addition of fertiliser, caused persistent acid production over time, which prevented the formation of insoluble metal phosphate phases and instead fostered an increased mobility of both metals and metalloids (As, Cd, Cu, Sb, Zn). By contrast, fertiliser application to a sulfide-rich soil with low organic carbon content and a sufficient acid buffering capacity to maintain near-neutral pH resulted in the immobilisation of Pb in the form of newly precipitated Pb phosphate phases. Thus, phosphate stabilisation was ineffective in suppressing metal and metalloid mobility from soils that were rich in organic matter, contained abundant pyrite and had a low acid buffering capacity. Phosphate stabilisation appears to be more effective for the in situ treatment of sulfide-rich soils that are distinctly enriched in Pb and contain insignificant concentrations of organic matter and other metals and metalloids.

Tree canopies are believed to act as a sink of atmospheric ammonia (NH₃). However, few studies have compared the uptake efficiency of different tree species. This study assessed the uptake of ¹⁵N-labelled NH₃ at 5, 20, 50 and 100 ppbᵥ by leaves and twigs of potted silver birch, European beech, pedunculate oak and Scots pine saplings in June, August and September 2008. Additionally, foliar uptake of ¹³C-labelled carbon dioxide (¹³CO₂) and leaf stomatal characteristics were determined per species and treatment date and the relation with ¹⁵NH₃ uptake and estimated stomatal ¹⁵NH₃ uptake were assessed. Both ¹⁵NH₃ and ¹³CO₂ uptake were affected by tree species and treatment date, but only ¹⁵NH₃ uptake was influenced by the applied NH₃ concentration. Depending on the treatment date, ¹⁵NH₃ uptake by leaves and twigs was highest at 5 (September), 20 (June) or 50 (August) ppbᵥ. Birch, beech and oak leaves showed the highest uptake in August, while for pine needles this was in June and, except at 5 ppbᵥ in June, the ¹⁵NH₃ uptake was always higher for the deciduous species than for pine. For all species except beech ¹³CO₂ uptake was highest in August and on every treatment date the ¹³CO₂ uptake by leaves of deciduous species was significantly higher than by pine needles. Leaf characteristics and ¹³CO₂ uptake did not provide a strong explanation for the observed differences in ¹⁵NH₃ uptake. This study shows that on the short-term a high interspecific variability exists in NH₃ uptake, which depends on the time in the growing season.

The effects of one of the most toxic heavy metals, lead (Pb), applied in two different concentrations and combined with chelate application were investigated on the water macrophyte (Pistia stratiotes L.) physiology. The influences were observed by the chlorophyll and free amino acid content determination. Also the lead accumulation in macrophyte biomass was investigated to assess the potential efficiency of this plant for rhizofiltration of highly Pb-polluted water. Na EDTA and Na citrate were used as chelates and Pb(NO3)2 as lead supplement. The application of organic chelates simulated conditions of an induced phytoextraction process. Statistical analyses were performed as a one-way ANOVA with a subsequent Tukey HSD test at a level of P < 0.05. Pb contents in both root and leaf tissues gradually increased with increasing Pb concentrations in the nutrient solution. More lead was accumulated in leaves than in roots within all treatments. The total chlorophyll content decreased with increased Pb concentration and with a higher content of chelates. The chelate addition increased the total amino acid content in leaves but decreased the total amino acid content in roots. The addition of lead with chelates decreased the dry biomass weight. However, water macrophyte showed extremely high lead accumulation in biomass in the short term (up to 8 days) and this accumulation potential could be used for relatively fast and effective decrease of high concentration of this risk element in contaminated water or sewage.

This report deals with the application of ion exchange columns to the treatment of groundwater contaminated by high concentrations of arsenic in the presence of sulphates. Two different process layouts were tested, based on the use of a single column and of two-in-series columns, respectively. Several breakthrough tests were performed, where the effect of the operating parameters, as the influent flow rate, the packed bed height and the feed water composition, were investigated. The collected data were described using three different modeling approaches, based on the Bohart–Adams, Yan and Thomas models, respectively. These models were all found to describe the experimental data with a quite good agreement (based on the R 2 value). The ion exchange capacity evaluated by the models (about 3.8 mEq/g) was comparable with the value provided by the supplier (3.8 mEq/g), but higher than the value determined through batch tests of a previous study by the same authors. The models were then successfully applied to describe the breakthrough behaviour of the two in-series column plant using a real feed contaminated by high arsenic concentrations in the presence of sulphate.

A polyaniline-modified quartz crystal microbalance (QCM) sensor was obtained through immobilizing the polyaniline film on the silver electrode surface of quartz crystal resonator by an electrochemical method. The sensor was studied for detecting the formic acid gas of different concentrations, and the results showed that the resonant frequency of QCM decreased quickly in the beginning and tended to be constant in the end when exposed to formic acid gas. The frequency shifts decreased faster as the concentration of formic acid gas increased. And the frequency shifts of the QCM sensors were found to be linearly related to the concentration of formic acid gas, which might be used to estimate the concentration level of the formic acid gas within the range of experimental concentrations. The result of on-line monitoring test fully indicated that the QCM sensor responded effectively to the increasing concentration of formic acid and had important practical significance and broad application prospect in real-time detection of antique conservation environment in the museum.

Odors, such as the malodorous and toxic hydrogen sulfide (H₂S), are released during leachate collection, storage, and treatment. A full-scale biofilter was applied to treat H₂S emitted from a leachate equalization basin in a sanitary landfill site. The inlet concentration of H₂S was 26.3–213.0 mg m⁻³. In steady state, total removal efficiency was over 90 % in summer and over 80 % in winter. The maximum elimination capacity achieved 9.1 g m⁻³ h⁻¹ at a loading rate of 10.5 g m⁻³ h⁻¹. The biofilter was effective at reducing H₂S. Factors on the level of H₂S inlet concentration and performance of the biofilter were investigated. The H₂S inlet load and removal efficiency relied on ambient and biofilter temperature, respectively. The water containing rate and relative humidity presented seasonal variation, according to which the interval period of irrigation could be optimized. The main product of H₂S degradation was sulfate, and sulfur also could be observed from the biofilter. Spatial and temporal shifts in bacterial community composition in the biofilter were determined by polymerase chain reaction-denaturing gradient gel electrophoresis followed by DNA sequence analysis. The present study revealed a correlation between biofilter performance and bacterial community structure, especially in a real application case.

The assessment of soil pollution with heavy metals has been studied, based on experimental soil and plant analytical heavy metal data obtained by a pot experiment conducted during 2010–2011 in a green house. A completely randomized block design was used, including the following sludge treatments (in tons per hectare): 0, 6, 12, 18, 24, 30, and (30+treated wastewater) in four replications. Lettuce (Lactuca sativa L.) var. longifolia was used as a test plant. Three indices were proposed, i.e., (1) elemental pollution index, (2) heavy metal load, and (3) total concentration factor. They were found to be linearly and statistically significantly related to the pollution load index, which was used as a reference index, and curvilinearly related to lettuce dry matter yield. It was concluded that the above indices could be used for the assessment of soil pollution level.