As an ecological factor, a magnetic field can affect insects causing a wide range of responses. The main purpose of this study was to analyze the fitness components (postembryonic development and viability of individuals) and the antioxidant defense (superoxide dismutase, catalase, and total glutathione) in laboratory strains of Drosophila subobscura, originating from oak and beech forests after exposure to the strong static magnet (2.4 T, VINCY Cyclotron magnet). The first instar larvae were placed near the north pole (N group) or the south pole (S group) of the magnet for 2 h. Oak and beech populations of D. subobscura had longer development time and lower viability in N and S groups compared to controls. These differences were significant only in S group of oak population and in N group of beech population. Total glutathione content was significantly decreased in both exposed groups of oak population, while catalase activity was significantly increased in both exposed groups of beech population. Being significantly decreased in both exposed groups of oak population and significantly increased in S group of beech population in comparison to controls, superoxide dismutase activity was observed in different values. According to the results, it can be stated that applied static magnetic field could be considered a potential stressor influencing the fitness components and antioxidant defense in Drosophila flies.

The influence of Chlorella sorokiniana on drinking water’s biological denitrification was studied at two different initial nitrate concentrations, 50 and 100 mg/L, respectively. Sucrose and grape juice were used as carbon sources. The experiments showed that the denitrification process in the presence of algae was, even at low concentrations, i.e. 50 mg/L of nitrate, slower than without them, but yet still more than 95 % of nitrate was removed in 24 h. It was also discovered that, with the addition of ammonium and urea, the urea interfered much more with the denitrification process, as less than 50 % of the initial nitrate was removed. However, algae did not contribute to the nitrate and ammonium removals, as the final concentrations of both in the presence of algae were higher by approx 5 %. At 100 mg/L of initial nitrate, the denitrification kinetics in the presence of algae was apparently slower regarding those experiments at lower levels of nitrate and only 65–70 % of nitrate was removed over 24 h. Using grape juice instead of sucrose improved the nitrate removal slightly.

Mineral carbonation of serpentinite mining residue offers an environmentally secure and permanent storage of carbon dioxide. The strategy of using readily available mining residue for the direct treatment of flue gas could improve the energy demand and economics of CO₂ sequestration by avoiding the mineral extraction and separate CO₂ capture steps. The present is a laboratory scale study to assess the possibility of CO₂ fixation in serpentinite mining residues via direct gas–solid reaction. The degree of carbonation is measured both in the absence and presence of water vapor in a batch reactor. The gas used is a simulated gas mixture reproducing an average cement flue gas CO₂ composition of 18 vol.% CO₂. The reaction parameters considered are temperature, total gas pressure, time, and concentration of water vapor. In the absence of water vapor, the gas–solid carbonation of serpentinite mining residues is negligible, but the residues removed CO₂ from the feed gas possibly due to reversible adsorption. The presence of small amount of water vapor enhances the gas–solid carbonation, but the measured rates are too low for practical application. The maximum CO₂ fixation obtained is 0.07 g CO₂ when reacting 1 g of residue at 200 °C and 25 barg (pCO₂ ≈ 4.7) in a gas mixture containing 18 vol.% CO₂ and 10 vol.% water vapor in 1 h. The fixation is likely surface limited and restricted due to poor gas–solid interaction. It was identified that both the relative humidity and carbon dioxide-water vapor ratio have a role in CO₂ fixation regardless of the percentage of water vapor.

The determination and remediation of three phenolic compounds bisphenol A (BPA), ortho-nitrophenol (o-NTP), parachlorophenol (PCP) in wastewater is reported. The analysis of these molecules in wastewater was done using gas chromatography (GC) × GC time-of-flight mass spectrometry while activated carbon derived from maize tassel was used as an adsorbent. During the experimental procedures, the effect of various parameters such as initial concentration, pH of sample solution, eluent volume, and sample volume on the removal efficiency with respect to the three phenolic compounds was studied. The results showed that maize tassel produced activated carbon (MTAC) cartridge packed solid-phase extraction (SPE) system was able to remove the phenolic compounds effectively (90.84–98.49 %, 80.75–97.11 %, and 78.27–97.08 % for BPA, o-NTP, and PCP, respectively) . The MTAC cartridge packed SPE sorbent performance was compared to commercially produced C18 SPE cartridges and found to be comparable. All the parameters investigated were found to have a notable influence on the adsorption efficiency of the phenolic compounds from wastewaters at different magnitudes.

Pot experiments were conducted to investigate the effects of γ-polyglutamic acid (γ-PGA), phosphate rock (PR), and γ-PGA-activated PR (γ-PGA-PR) on the immobilization and phytotoxicity of Pb in a contaminated soil. The proportion of residual Pb (Re-Pb) in soil was reduced by the addition of γ-PGA but was increased by the application of PR and γ-PGA-PR. The addition of γ-PGA in soil improved the accumulation of Pb in pak choi and decreased the growth of pak choi, suggesting the intensification of Pb phytotoxicity to pak choi. However, opposite effects of PR and γ-PGA-PR on the phytotoxicity of Pb to pak choi in soil were observed. Moreover, in the examined range, γ-PGA-PR activated by a higher amount of γ-PGA resulted in a greater proportion of Re-Pb in soil and weaker phytotoxicity of Pb to pak choi. The predominance of γ-PGA-PR in relieving the phytotoxicity of Pb was ascribed mainly to the increase of soil pH and available phosphate after the amendment, which could facilitate the precipitation of Pb in soil and provide pak choi with more phosphorus nutrient.

High nitrogen (N) concentrations in rural domestic water supplies have been attributed to excessive agricultural N leaching into shallow groundwater systems; therefore, it is important to determine the impact of agriculture (e.g., rice production) on groundwater quality. To understand the impact of agricultural land use on the N concentrations in the shallow groundwater in subtropical central China, a large observation program was established to observe ammonium-N (NH₄-N), nitrate-N (NO₃-N), and total N (TN) concentrations in 161 groundwater observation wells from April 2010 to November 2012. The results indicated that the median values of NH₄-N, NO₃-N, and TN concentrations in the groundwater were 0.15, 0.39, and 1.38 mg N L⁻¹, respectively. A total of 36.3 % of the water samples were categorized as NH₄-N pollution, and only a small portion of the samples were categorized as NO₃-N pollution, based on the Chinese Environmental Quality Standards for Groundwater of GB/T 14848-93 (General Administration of Quality Supervision of China, 1993). These results indicated of moderate groundwater NH₄-N pollution, which was mainly attributed to intensive rice agriculture with great N fertilizer application rates in the catchment. In addition, tea and vegetable fields showed higher groundwater NO₃-N and TN concentrations than other agricultural land use types. The factorial correspondence analysis (FCA) suggested that the flooded agricultural land use types (e.g., single-rice and double-rice) had potential to impose NH₄-N pollution, particularly in the soil exhausting season during from July to October. And, the great N fertilizer application rates could lead to a worse NO₃-N and TN pollution in shallow groundwater. Hence, to protect groundwater quality and minimize NH₄-N pollution, managing optimal fertilizer application and applying appropriate agricultural land use types should be implemented in the region.

Seasonal changes in the levels of PM₁ and its main components (organic carbon (OC), elemental carbon (EC), SO₄ ²⁻, NO₃ ⁻ and NH₄ ⁺) were studied in an urban street canyon in southeastern Spain. Although PM₁ levels did not show an evident seasonal cycle, strong variations in the concentrations of its major components were observed. Ammonium sulfate, the main secondary inorganic compound, was found to be of regional origin. Its formation was favored during summer due to increased photochemical activity. In contrast, the concentrations of particulate ammonium nitrate, which is thermally unstable, were highest in winter. Although traffic emissions are the dominant source of EC in the city, variations in traffic intensity could not explain the seasonal cycle of this component. The higher EC concentrations during the cold months were attributed to the lower dispersion conditions and the increase in EC emissions. Special attention has been given to variations in organic carbon levels since it accounted for about one third of the total PM₁ mass. The concentrations of both total OC and secondary OC (SOC) were maxima in winter. The observed seasonal variation in SOC levels is similar to that found in other southern European cities where the frequency of sunny days in winter is high enough to promote photochemical processes.

Acetate- and citrate-buffered quick, easy, cheap, effective, rugged, safe (QuEChERS) pretreatment methods were evaluated for the determination of various pesticides in peaches, grapes, apples, bananas, pears, and strawberries from various regions of Greece, using LC-MS/MS. The purposes of this study were (i) to evaluate which type of QuEChERS method was the most appropriate and effective for each matrix; (ii) to apply the selected QuEChERS method for each matrix, in order to detect and quantify pesticide residues in various fruit samples using UPLC-MS/MS; (iii) to examine the concentration distribution of pesticide classes among fruit originating from various areas; and (iv) to assess pesticide concentration distribution between peel and flesh of fruit in order to evaluate the penetration of pesticide residues in the fruit flesh. Acetate-buffered QuEChERS was found to be the most suitable technique for most of the fruit matrices. According to the recovery values at two different concentration levels, peaches should preferably be treated by the citrate-buffered type, whereas grapes, bananas, apples, pears, and strawberries are best treated by the acetate-buffered version, although the differences in efficiency were small. The addition of graphitized carbon black significantly decreases the recovery of specific pesticides in all matrices except for strawberries. The majority of values do not exceed the official maximum residue levels set by the European Commission. Organophosphates proved to be the most commonly detected category along with triazines-triazoles-conazoles group and by carbamates. Apples and pears seem to be the most contaminated fruit matrices among those tested. Distribution of pesticide classes shows variations between different regions, suggesting different pesticide application practices. In the case of peaches and pears, there is an equal distribution of detected pesticides between peel and flesh, indicating penetration of contaminants into the fruit flesh.

Due to differences in stereostructure, enantiomeric compositions and enantiomeric ratios (ERs) of chiral compounds can be used to discriminate environmental processes such as abiotic and biotic degradation/transformation. In this study, the ERs of two chiral polycyclic musks, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), were investigated in the sediments of Zhujiang River and Dongjiang River in the Pearl River Delta (PRD), as well as in those of Suzhou Creek in Shanghai City. The results indicated that ER cᵢₛ of HHCB varied significantly, ranging from 1.09 to 1.53 and 1.40 to 1.48 in the PRD and Suzhou Creek samples, respectively, whereas ER ₜᵣₐₙₛ of HHCB exhibited limited variation, ranging from 0.98 to 1.10 and 0.98 to 1.05 for Pearl River and Suzhou Creek samples, respectively. In addition, ERs of AHTN varied substantially from 1.10 to 1.34 and 1.17 to 1.28 in the PRD and Suzhou Creek, respectively. These results suggest that HHCB in the sediment in the study area underwent biotic degradation and the preferential biotransformation isomer was (4R,7S)-HHCB, while AHTN simultaneously underwent a certain degree of biotic degradation/transformation.

In this study, positive matrix factorization (PMF) and principal components analysis (PCA) were combined to identify and apportion pollution-based sources of hazardous elements in the surface sediments in the Yangtze River estuary (YRE). Source identification analysis indicated that PC1, including Al, Fe, Mn, Cr, Ni, As, Cu, and Zn, can be defined as a sewage component; PC2, including Pb and Sb, can be considered as an atmospheric deposition component; and PC3, containing Cd and Hg, can be considered as an agricultural nonpoint component. To better identify the sources and quantitatively apportion the concentrations to their sources, eight sources were identified with PMF: agricultural/industrial sewage mixed (18.6 %), mining wastewater (15.9 %), agricultural fertilizer (14.5 %), atmospheric deposition (12.8 %), agricultural nonpoint (10.6 %), industrial wastewater (9.8 %), marine activity (9.0 %), and nickel plating industry (8.8 %). Overall, the hazardous element content seems to be more connected to anthropogenic activity instead of natural sources. The PCA results laid the foundation for the PMF analysis by providing a general classification of sources. PMF resolves more factors with a higher explained variance than PCA; PMF provided both the internal analysis and the quantitative analysis. The combination of the two methods can provide more reasonable and reliable results.