A method combining ultrasound-assisted emulsification–microextraction (USAEME) with gas chromatography–mass spectrometry (GC–MS) was developed for simultaneous determination of four acidic pharmaceuticals, ibuprofen, naproxen, ketoprofen, and diclofenac, as well as four phenols, 4-octylphenol, 4-n-nonylphenol, bisphenol A, and triclosan in municipal wastewaters. Conditions of extraction and simultaneous derivatization were optimized with respect to such aspects as type and volume of extraction solvent, volume of derivatization reagent, kind and amount of buffering salt, location of the test tube in the ultrasonic bath, and extraction time. The average correlation coefficient of the calibration curves was 0.9946. The LOD/(LOQ) values in influent and effluent wastewater were in the range of 0.002–0.121/(0.005–0.403) μg L⁻¹and 0.002–0.828/(0.006–2.758) μg L⁻¹, respectively. Quantitative recoveries (≥94 %) and satisfactory precision (average RSD 8.2 %) were obtained. The optimized USAEME/GC–MS method was applied for determination of the considered pharmaceuticals and phenols in influents and treated effluents from nine Polish municipal wastewater treatment plants. The average concentration of acidic pharmaceuticals in influent and effluent wastewater were in the range of 0.06–551.96 μg L⁻¹and 0.01–22.61 μg L⁻¹, respectively, while for phenols were in the range of 0.03–102.54 μg L⁻¹and 0.02–10.84 μg L⁻¹, respectively. The removal efficiencies of the target compounds during purification process were between 84 and 99 %.

In this paper, degradation of a mixture of three azo dyes was studied by the photo-assisted electrochemical process using an O₂-diffusion cathode containing carbon nanotubes and boron-doped diamond (BDD) anode. The concentration of three textile dyes (C.I. Acid Orange 8 (AO8), C.I. Acid Orange 10 (AO10), and C.I. Acid Orange 12 (AO12)) was determined simultaneously despite the severe overlap of their spectra. For this purpose, partial least square (PLS), as a multivariate calibration method, was utilized based on recording UV–Vis spectra during the decolorization process. Moreover, the central composite design was used for the modeling of photo-assisted electrochemical decolorization of the aqueous solutions containing three dyes. The investigated parameters were the initial concentration of three dyes, applied current and reaction time. Analysis of variance (ANOVA) revealed that the obtained regression models match the experimental results well with R (Khataee et al. 2010, Clean-Soil Air Water 38 (1):96–103, 2010) of 0.972, 0.971, and 0.957 for AO8, AO10, and AO12, respectively. Three-dimensional surface and contour plots were applied to describe the relation between experimental conditions and the observed response. The results of TOC analysis confirmed good ability of proposed photo-assisted electrochemical process for degradation and mineralization of textile industry wastewater.

To investigate the effect of organic matter evolution on heavy metal sorption, fluorescence excitation–emission matrix (EEM) spectra combined with parallel factor (PARAFAC) analysis were employed to characterize the evolution and metal-complexing potential of fluorescent water-extractable organic matter (WEOM) from composted municipal solid wastes (MSWs). The WEOMs examined comprised humic-, fulvic-, tryptophan-, and tyrosine-like substances. Composting treatment increased the content of humic- and fulvic-like matter, and changed the existence pattern of tryptophan- and tyrosine-like substances (i.e., the tryptophan- and tyrosine-like substances from uncomposted MSWs were mainly bound in protein-like matter, whereas those from composted MSWs were primarily bound in humic- and fulvic-like substances). Furthermore, composting treatment increased the polar functional group, aromaticity, and humification degree of the WEOMs, but decreased the aliphatic and hydroxyl group. These evolutions decreased the Cu(II) affinities of fulvic- and humic-like substances and the Pb(II) affinities and complexing capacities of fulvic-like substances, but increased the Cu(II) complexing capacities of fulvic- and humic-like substances. These results reveal that mature composts from the MSWs can be used for the remediation of Cu- and Pb-contaminated soils in situ, whereas immature composts can enhance the metal transferability from soil to plant.

The influence of two neonicotinoids, i.e., imidacloprid (IMI) and acetamiprid (ACE), on soil microbial activities was investigated in a short period of time using a combination of the microcalorimetric approach and enzyme tests. Thermodynamic parameters such as QT(J g⁻¹soil), ∆Hₘₑₜ(kJ mol⁻¹), JQ/S(J g⁻¹ h⁻¹), k (h⁻¹), and soil enzymatic activities, dehydrogenase, phosphomonoesterase, arginine deaminase, and urease, were used to evaluate whole metabolic activity changes and acute toxicity following IMI and ACE treatment. Various profiles of thermogenic curves reflect different soil microbial activities. The microbial growth rate constant k, total heat evolution QT(expect for IMI), and inhibitory ratio I show linear relationship with the doses of IMI and ACE. QTfor IMI increases at 0.0–20 μg g⁻¹and then decreases at 20–80 μg g⁻¹, possibly attributing to the presence of tolerant microorganisms. The 50 % inhibitory ratios (IC₅₀) of IMI and ACE are 95.7 and 77.2 μg g⁻¹, respectively. ACE displays slightly higher toxicity than IMI. Plots of k and QTagainst microbial biomass-C indicate that the k and QTare growth yield-dependent. IMI and ACE show 29.6; 40.4 and 23.0; and 23.3, 21.7, and 30.5 % inhibition of dehydrogenase, phosphomonoesterase, and urease activity, respectively. By contrast, the arginine deaminase activity is enhanced by 15.2 and 13.2 % with IMI and ACE, respectively. The parametric indices selected give a quantitative dose-response relationship of both insecticides and indicate that ACE is more toxic than IMI due to their difference in molecular structures.

The effects of several silicates (talcum powder (TP), calcium silicate (CS), sodium silicate (SS), and potassium silicate (PS)), in comparison with other amendments (quicklime (QL) and potassium dihydrogen phosphate (PDP)) on cadmium (Cd) uptake by three dicotyledonous crops (Amaranthus hypochondriacus L. Cv. ‘K112’, Amaranthus tricolor L., and Brassica oleracea var. albiflora Kuntze) were investigated in Cd–contaminated soil. The effects of both application methods of amendments (singly and combined) and timing of application were also evaluated. Sodium silicate was the most effective in reducing crop Cd uptake and translocation, which was diminished by 51 % in roots, 53 % in stems, and 72 % in leaves on average. Application of CS amendment showed greater efficiency than PDP amendment in decreasing Cd uptake by crops and resulted in increased biomass. Potassium silicate only slightly decreased shoot Cd concentration. Combination of PDP and SS was able to overcome the inhibitory effect of SS on crop yield while decreasing Cd concentrations in roots, stems and leaves of the tested crops by average rates of 52, 65, and 68 % respectively. Applications of SS and PS significantly reduced the root-to-shoot Cd transfer factor. We found that Si accumulation in crops was not associated with lower Cd concentration, indicating that Si in crops may play a major role in alleviating metal stress rather than inhibiting crop Cd accumulation. We suggested that the inhibitive effect of silicates on crops Cd uptake was majorly attributed to the properties of the silicates, those were their specific effects on soil pH and cations, which increased Cd adsorption by soil and suppressed Cd uptake from soil solution by increasing the relative dissolved concentrations of competing cations.

Agricultural pollution caused by the use of plastic sheetings has been documented to be a widespread problem in most of the major crop-planting regions of the world. In order to better understand the phytotoxic mechanisms induced by phthalic acid esters involved with this problem, Cucumber sativus L. cv Jinyan No. 4 were sown in pots to the three-leaf-stage in the presence of di-n-butyl phthalate (DBP; 0, 30, 50, 100, and 200 mg L⁻¹) for 1, 3, 5, or 7 days. Physiology, biochemistry, and ultrastructure of seedling roots were examined. The results indicated that activities of three antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) were stimulated at low-DBP treatments and decreased under higher levels (>100 mg L⁻¹) compared to the controls. On the other hand, SOD and POD provided a better defense against DBP-induced oxidative damage in the roots of cucumber seeding, compared to CAT. The productions of both malondialdehyde (MDA) and proline (Pro) were promoted under DBP stress. Visible impact on the cytoderm, mitochondrion, and vacuole was detected, possibly as a consequence of free radical generation. These results suggested that activation of the antioxidant system by DBP led to the formation of reactive oxygen species that resulted in cellular damage.

Sorption interaction of chlorimuron-ethyl with montmorillonite clays was investigated under varied types of exchangeable cation, pH, and ionic strength conditions. Chlorimuron-ethyl sorption on bentonites exhibited pronounced cation dependency, and the sorption ability increased as the sequence Ca²⁺- < Na⁺- < Al³⁺- < Fe³⁺-bentonite, due to different sorption mechanisms, whereas the cation dependency was influenced by the clay type and much weaker for montmorillonites. The decrease of pH at the range of 4.0–6.0 prominently increased sorption of chlorimuron-ethyl on all cation-exchanged montmorillonite clays, and nearly a neglected sorption (about 2 %) can be observed at pH over 7.0. In the presence of CaCl₂, sorption of chlorimuron-ethyl on Fe³⁺-bentonite was promoted because of complexion of Ca²⁺ and the surface of Fe³⁺-bentonite. However, as the concentration of CaCl₂ increased, chlorimuron-ethyl sorption on Ca²⁺- and Fe³⁺-exchanged bentonite decreased, suggesting that Ca bridging was not the prevailing mechanism for sorption of chlorimuron-ethyl on these clays. Furthermore, chlorimuron-ethyl sorption was relatively sensitive to pH, and the change of pH may obscure effect of other factors on the sorption, so it was quite necessary to control pH at a constant value when the effect of other factor was being studied.

The present field study, conducted during the spawning period (April/May) of European chub (Squalius cephalus L.) from the Sava River in Croatia, indicates that seasonal changes of fish physiological state might cause variability in gastrointestinal metal (Cd, Cu, Fe, Mn and Zn), total cytosolic protein and metallothionein (MT) levels. During the period of fish spawning and increased metabolic activity, a significant relationship with chub hepatosomatic index was evident for Fe and Mn in gastrointestinal tissue (r = 0.35 and 0.26, respectively) and in cytosolic fraction (r = 0.32 and 0.41, respectively) and for Zn and Fe in the gut content (r = 0.36 and 0.31, respectively). Total cytosolic protein and MT concentrations followed the same spatial distribution as Fe and Mn in all gastrointestinal fractions and as Zn in the sub-cellular fractions, with higher levels at upstream locations. Due to the role of essential metals in metabolic processes and gonad development, increased feeding and spawning activity in April/May resulted in higher gastrointestinal essential metal (Fe, Mn and Zn) and MT concentrations, which probably follow an increase in Zn concentrations, known as the primary MT inducer. Therefore, biotic factors should be considered as important confounding factors in metal exposure assessment, while their influence on gastrointestinal metal and protein levels should be interpreted depending on the season studied.

To evaluate the effects of manure application on continuous maize seed production, 10-year cattle manure on soil properties, heavy metal in soil and plant were evaluated and investigated in calcareous soil. Results showed that manure application increased soil organic matter, total and available nutrients, pH, and electrical conductivity (EC), and the most massive rate caused the highest increase. Manure application led to an increase in exchangeable fraction and an increase of availability of heavy metal. Residual fraction was dominant among all metals, followed by the fraction bound to Fe and Mn oxides. Manure application involved accumulation of heavy metal on corn, but the accumulation in the stem is higher than that in the seed. Manure application led to a high deficiency of total Zn and high accumulation of total Cd in the soil of corn seed production, which should be a risk for safety seed production in calcareous soil in Northwest China.

Studies on endocrine disruption in Australia have mainly focused on wastewater effluents. Limited knowledge exists regarding the relative contribution of different potential sources of endocrine active compounds (EACs) to the aquatic environment (e.g., pesticide run-off, animal farming operations, urban stormwater, industrial inputs). In this study, 73 river sites across mainland Australia were sampled quarterly for 1 year. Concentrations of 14 known EACs including natural and synthetic hormones and industrial compounds were quantified by chemical analysis. EACs were detected in 88 % of samples (250 of 285) with limits of quantification (LOQ) ranging from 0.05 to 20 ng/l. Bisphenol A (BPA; LOQ = 20 ng/l) was the most frequently detected EAC (66 %) and its predicted no-effect concentration (PNEC) was exceeded 24 times. The most common hormone was estrone, detected in 28 % of samples (LOQ = 1 ng/l), and the PNEC was also exceeded 24 times. 17α-Ethinylestradiol (LOQ = 0.05 ng/l) was detected in 10 % of samples at concentrations ranging from 0.05 to 0.17 ng/l. It was detected in many samples with no wastewater influence, and the PNEC was exceeded 13 times. In parallel to the chemical analysis, endocrine activity was assessed using a battery of CALUX bioassays. Estrogenic activity was detected in 19 % (53 of 285) of samples (LOQ = 0.1 ng/l 17β-estradiol equivalent; EEQ). Seven samples exhibited estrogenic activity (1–6.5 ng/l EEQ) greater than the PNEC for 17β-estradiol. Anti-progestagenic activity was detected in 16 % of samples (LOQ = 8 ng/l mifepristone equivalents; MifEQ), but the causative compounds are unknown. With several compounds and endocrine activity exceeding PNEC values, there is potential risk to the Australian freshwater ecosystems.