PURPOSE: Although the ecotoxicological effects of copper (Cu) on grapevine are of global concern due to the intensive and long-term application of Cu-based fungicides in vineyards, comparatively little is known about the phytotoxicity, accumulation, and translocation of Cu in grapevines. Therefore, this study was to conduct a hydroponic experiment to determine the influence of solution Cu concentration not only on bioaccumulation and the translocation of Cu in grapevine roots, stems, and leaves, but also on the subsequent growth inhibition of the roots. METHODS: Grapevine cuttings were grown for 30 days and then exposed to various Cu concentrations (0.1–50 μM) for 15 days. The dose–response profile was described by a sigmoid Hill equation. Optical microscopy was used to examine the cytotoxicity of Cu on the roots. In addition, bioaccumulation factors (BAFs) and translocation factors (TFs) were calculated from the results of the hydroponic experiment. RESULTS: Copper was tolerated by grapevines at a concentration ≤1 μM. The median inhibition concentration (IC50) obtained from the Hill model was 3.94 μM (95% confidence interval, 3.65–4.24). From the light micrographs of root tip cells, signs of toxicity including increased vacuolization and plasmolysis were observed at solution Cu concentrations ≥10 μM. In addition, a higher Cu concentration was found in the roots (25–12,000 mg kg−1) than in the stems (5–540 mg kg−1) and leaves (7–46 mg kg−1), indicating a very limited translocation of Cu from the roots to the aboveground parts. CONCLUSIONS: This study investigated not only the macroscopic root growth and Cu accumulation by grapevine, but also the microscopic changes in root tissue at the cell level after the exposure experiment. Based on the BAFs and TFs, the grapevine could be considered a Cu-exclusive plant. For toxic effects on the exposure of roots to Cu, this study also revealed that root growth, as well as the histological changes in rhizodermal cells, can be used as phytotoxic indicators of grapevine under Cu stress.

INTRODUCTION: Schwertmannite was synthesized through an oxidation of FeSO4 by Acidithiobacillus ferrooxidans LX5 cell suspension at an initial pH 2.5 and 28°C for 3 days and characterized using X-ray diffraction spectroscopy and scanning electron microscope. The schwertmannite photocatalytic degradation of methyl orange (MO) by oxalate was investigated at different initial pH values, concentrations of schwertmannite, oxalate, and MO. RESULTS: The results demonstrated that photodegradation of MO in the presence of schwertmannite or oxalate alone was very weak. However, the removal of MO was significantly enhanced when schwertmannite and oxalate coexisted in the reaction system. Low pH (4 or less) was beneficial to the degradation of MO. The optimal doses of schwertmannite and oxalate were 0.2 g L−1 and 2 mM, respectively. Hydroxyl radicals (·OH) and Fe(II), the intermediate products, were also examined during the reaction to explore their correlation with the degradation of MO. CONCLUSION: A possible mechanism for the photocatalytic decomposition of MO in the study was proposed. The formation of Fe(III)-oxalate complexes on the surface of schwertmannite was a precursor of H2O2 and Fe(II) production, further leading to the yield of ·OH responsible for the decomposition of MO.

PURPOSE: Biosorption is an emerging, eco-friendly and economical method for treating the wastewater effluents. Compared to many other biological materials, algae biomass proved to be the better biosorbent due to the presence of cell wall polymers in them. METHODS: Algal biomasses namely Enteromorpha flexuosa and Gracilaria corticata were dried, crushed and used as biosorbents. Ponceau S, a diazo dye was used as a model adsorbate for the biosorption studies. The biosorbents were characterized by Scanning Electron Microscopy, FT-IR and zero point charge. Batch studies were performed by varying pH, biosorbent dosage and initial dye concentrations. Adsorption isotherms, kinetic and thermodynamic analyses were carried out. The effect of electrolytes was also studied. Batch desorption studies were also carried out using various reagents. RESULTS: Isotherm data were tested with Langmuir and Freundlich isotherm models and the results suggested that the Freundlich isotherm fitted the data well. Kinetic studies were performed with varying initial dye concentrations and the data were incorporated with pseudo first-order and pseudo second-order kinetic equations and was found that the studied biosorption processes followed pseudo second-order kinetic equation. Thermodynamic parameters were evaluated at three different temperatures 293 K, 300 K and 313 K. About 95% of the dye could be desorbed from both the biosorbents. CONCLUSION: Both the algal biomasses had heterogeneous surfaces and followed pseudo second-order chemical kinetics. Thermodynamic parameters proved that the biosorption by both the biomasses were spontaneous, feasible and endothermic processes. Desorption studies proved the worth of the algal biomasses as biosorbents in industrial level.

PURPOSE: In this study, a novel and ecological alternative have been developed to treat soils contaminated with hexavalent chromium coupling two well-known systems: electrokinetic remediation and permeable reactive biobarriers. The electric field promotes the electromigration of the hexavalent chromium oxyanions towards the anode. The biobarriers were placed before the anode electrode, in order to promote the reduction and retention of the chromium migrating in its direction. Thus, this technology provided a global treatment to soil removal without subsequent treatments of the contaminated effluents. METHODS: The electrokinetic system was coupled with two different permeable reactive biobarriers composed by Arthrobacter viscosus bacteria, supported either in activated carbon or zeolite. An electric field of 10 V was applied and two different treatment times of 9 and 18 days were tested. RESULTS: Removal values of 60% and 79% were obtained when electrokinetic treatment was coupled with zeolite and activated carbon biobarriers, respectively, for a test period of 18 day. The reduction of hexavalent chromium to trivalent chromium was around 45% for both systems. CONCLUSIONS: In this work, two types of biobarriers were efficiently coupled to electrokinetic treatment to decontaminate soil with Cr(VI). Furthermore, the viability of the new coupling technology developed (electrokinetic + biobarriers) to treat low-permeability polluted soils was demonstrated.

Perfluorinated compounds (PFCs) have been widely used in industrial and consumer products and frequently detected in many environmental media. Potential reproductive effects of perfluorooctanesulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA) have been reported in mice, rats and water birds. PFOS and PFOA were also confirmed developing toxicants towards zebrafish embryos; however, the reported effect concentrations were contradictory. Polyfluorinated alkylated phosphate ester surfactants (including FC807) are precursor of PFOS and PFOA; however, there is no published information about the effects of FC807 and PFNA on zebrafish embryos. Therefore, this study was conducted to determine the effects of these four PFCs on zebrafish embryos. Normal fertilized zebrafish embryos were selected to be exposed to several concentrations of PFOA, PFNA, PFOS or FC807 in 24-well cell culture plates. A digital camera was used to image morphological anomalies of embryos with a stereomicroscope. Embryos were observed through matching up to 96-h post-fertilization (hpf) and rates of survival and abnormalities recorded. PFCs caused lethality in a concentration-dependent manner with potential toxicity in the order of PFOS > FC807 > PFNA > PFOA based on 72-h LC₅₀. Forty-eight-hour post-fertilization pericardial edema and 72- or 96-hpf spine crooked malformation were all observed. PFOA, PFNA, PFOS and FC807 all caused structural abnormalities using early stages of development of zebrafish. The PFCs all retarded the development of zebrafish embryos. The toxicity of the PFCs was related to the length of the PFC chain and functional groups.

PURPOSE: Perfluorinated compounds (PFCs) are widely distributed from industrialized to remote locations throughout the world. This study demonstrates the spatial distributions of PFCs in water and sediments from the L’Albufera Natural Park (Valencia, Spain). METHODS: Grab water and sediment samples were collected. PFCs were extracted from sediments with acidified acetonitrile by ultrasonication and cleaned up by solid-phase extraction (SPE) and from water by SPE. Determination was carried out by liquid chromatography–tandem mass spectrometry. RESULTS: In 100% of the samples (both water and sediments), perfluorooctane sulfonate (PFOS) and perfluoroctanoic acid (PFOA) were the predominant PFCs. Among the 12 sampling sites, PFOS concentrations in sediments ranged from 0.10 to 4.80 ng/g dry weight and in water from 0.94 to 58.1 ng/L. PFOA concentrations in sediment were from 0.004 to 1.24 ng/g and in water from 0.99 to 120 ng/L. Other perfluorocarboxylic acids (C5, C6, C7, C9, and C10) and perfluorosulfonates (C4 and C10) were also identified in several locations. The sum of all 10 compounds (ΣPFCs) concentration range from 0.99 to 120 ng/L in water and from 0.25 to 17.4 ng/g in sediments. Sediment–water distribution coefficients (log K D) were in the range 2.31–4.51 and positively correlated with perfluoroalkyl chain length. CONCLUSIONS: PFC concentrations in water and sediment were both less than those able to cause acute toxicity; low but detectable PFCs pollution in the L’Albufera Natural Park in Valencia was demonstrated. These compounds are bioaccumulative; thus, the risk associated with these exposures requires a deeper evaluation of long-term chronic toxicity.

Manure products fermented underground in cow horns and commonly used as field spray (preparation 500) in the biodynamic farming system, were characterized for molecular composition by solid-state nuclear magnetic resonance [13 C cross-polarization magic-angle-spinning NMR (13 C-CPMAS-NMR)] spectroscopy and offline tetramethylammonium hydroxide thermochemolysis gas chromatography-mass spectrometry. Both thermochemolysis and NMR spectroscopy revealed a complex molecular structure, with lignin aromatic derivatives, polysaccharides, and alkyl compounds as the predominant components. CPMAS-NMR spectra of biodynamic preparations showed a carbon distribution with an overall low hydrophobic character and significant contribution of lignocellulosic derivatives. The results of thermochemolysis confirmed the characteristic highlighted by NMR spectroscopy, revealing a molecular composition based on alkyl components of plant and microbial origin and the stable incorporation of lignin derivatives. The presence of biolabile components and of undecomposed lignin compounds in the preparation 500 should be accounted to its particularly slow maturation process, as compared to common composting procedures. Our results provide, for the first time, a scientific characterization of an essential product in biodynamic agriculture, and show that biodynamic products appear to be enriched of biolabile components and, therefore, potentially conducive to plant growth stimulation.

Plant litter and organic sediments are a main sink for metals and metalloids in aquatic ecosystems. The effect of invertebrate shredder (a key species in litter decay) on metal/metalloid fixation by organic matter is described only under alkaline water conditions whereas for slightly acidic waters nothing can be found. Furthermore, less is known about the effect of invertebrate shredders on the quality of dissolved organic carbon (DOC) and nitrogen (DON) released during litter decay. We conducted an experiment to investigate the impact of invertebrate shredder (Gammarus pulex) on metal/metalloid fixation/remobilization and on the quality of DOC/DON released under slightly acidic water conditions. During decomposition of leaf litter, invertebrate shredder facilitated significantly the emergence of smaller particle sizes of organic matter. The capacity of metal fixation was significantly higher in smaller particles (POM 2,000–63 μm) compared to original leaf litter and litter residues. Thus, G. pulex enhanced metal fixation by organic partition of sediments by increasing the amount of smaller particle of organic matter in aquatic ecosystems. In contrast, the capacity of metal/metalloid fixation in the smallest fraction of POM (<63 μm) was lower compared with leaf residues in treatment without invertebrates. Remobilization of metals and metalloids was very low for all measured elements. A significant effect of invertebrates on quantitative formation of DOC/DON was confirmed. The quality of released DOC/DON, which may affect metal/metalloid remobilization, was also significantly affected by invertebrate shredders (e.g., more carboxylates). Hence, invertebrate shredder enhanced significantly the fixation of metals/metalloids into POM in slightly acidic environments.

OBJECTIVE: In this work, continuous and size-segregated aerosol measurements at Mt. Krvavec, Slovenia, during the Eyjafjallajökull volcanic eruption were performed. Based on chemical and morphological characteristics of size-segregated particles, the presence of the volcanic aerosols after long-range transport to Slovenia was to be confirmed. RESULTS AND CONCLUSIONS: Continuous measurements with the aethalometer and SMPS indicated the suspected volcanic ash plume passing over the sampling site. The aerosols collected by discrete sampling showed a chemical signature similar to the known elemental signature of the Icelandic volcanic ash. Coarse particles showed a composition typical for silicates rich in metals; in many cases also S was present. Morphological analysis showed particles with features indicative of an explosive volcanic eruption, e.g., pumice and pumice shards, glass shards, minerals, evidence of steam condensation, etc. The high sulfate concentration associated with the fine particles resulted in sulfate crystallization within the cascade impactor leading to the formation of large structures resembling a “fern”. Mass size distributions for Fe, Ti, Mn, Ca, Na, and Mg showed one primary peak (for Fe, Mn, and Ti at 2.8 μm; for Ca, Na, and Mg at ca. 4 μm), which supports the fact that most of the particles in the coarse sizes were silicates rich in metals. The size distribution of the water-soluble SO 4 2− showed a maximum peak at 0.75 μm, which also confirms the high sulfate concentration in the fine particles. Chemical and morphological characterization of aerosols collected at Mt. Krvavec indeed confirmed that volcanic ash plume passed over Slovenia.

BACKGROUND, AIM, AND SCOPE: Olive oil mill wastewater (OMW), a by-product of the olive oil extraction process, is annually produced in huge amounts in olive-growing areas and represents a significant environmental problem in Mediterranean areas. We studied the impact of OMW dilutions (1:20 and 1:10) on spinach plants in order to evaluate OMW dilutions as a low-cost alternative method for the disposal of this waste. MATERIALS AND METHODS: The effects of OMW dilutions were evaluated on seed germination, shoot and root elongation, biomass production, nutrient uptake and translocation, ascorbic acid content, polyphenols, photosynthetic pigments, and photosynthetic performance of spinach. RESULTS: Plant biomass was more affected than plant height and total chlorophyll; carotenoid and ascorbic acid content progressively decreased with decreasing OMW dilution. Exposure to both OMW dilutions resulted in overaccumulation of total polyphenols, which were negatively correlated to plant biomass and nutrients. Nutrient (Fe, Ca, and Mg) content was insufficient leading to reduced growth. Water use efficiency decreased mainly due to decreased CO2 assimilation rate rather than to a decline of transpiration rate. Disturbances in photosystem II (PSII) photochemical efficiency could be better envisaged by the ratio between variable fluorescence and initial fluorescence (Fv/Fo), which showed much greater amplitude than the maximal photochemical efficiency of PSII photochemistry (Fv/Fm). CONCLUSIONS: From the data obtained, it is suggested that 1:20 OMW dilutions are still phytotoxic and that higher OMW dilutions should be used in order to use this waste for the irrigation of spinach plants.