A pot experiment was conducted in order to study the relationships of soil pollution indices to maize (Zea mays L.) growth characteristics and soil and plant heavy metal content, as well as the metal plant uptake. A completely randomized block design was used, including 11 treatments in three replications. The treatments applied were control (freshwater), four levels of inorganic NPK fertilizer combined with treated municipal wastewater and freshwater and three sludge levels (5, 25 and 50 %, respectively) in the presence of treated wastewater and freshwater, respectively. The mean effect of the applied sludge levels independent of the presence of the freshwater or wastewater contributed to the accumulation of heavy metals Cr, Cu, Zn and Mn in soil and in leaves. The soil pollution indices, i.e., pollution load index (PLI), elemental pollution index (EPI), total concentration factor and heavy metal load, showed that the soil had been polluted with heavy metals to a great extent. The application of sludge treatment affected positively the maize plant height, leaf number and the indices PLI and EPI. All pollution indices studied were positively related to plant leaf number and plant height, as well to heavy metal soil content.

The accumulation of Ag by the marine herbivorous gastropod, Littorina littorea, has been studied in a series of exposures in which the metal was added in aqueous form and as nanoparticles, both in the presence and absence of contaminated algal food (Ulva lactuca). Significant accumulation occurred in the gill, kidney, stomach and visceral mass when the snail was exposed to aqueous Ag in the absence of food. Despite the consumption of U. lactuca that had been previously contaminated by Ag, no accumulation was observed from the dietary route. When added as nanoparticles, accumulation of Ag was only measured in the head and gill and only in the absence of contaminated food. These observations suggest that Ag is most bioavailable to L. littorina when in true solution and that Ag measured in external tissues of the snail following exposure to nanoparticles arises from some physical association that does not result in significant transfer of the metal to internal organs.

Trace element concentrations on a dry ash basis in saline-irrigated biomass feedstock from the San Joaquin Valley are investigated using multi-element spectroscopic techniques. The results show high concentrations of both Na and K compared to local baseline soil. The content of Na is higher than observed for nonsaline-irrigated biomass reflecting the salinity of the drainage water. The alkali earth elements as well as other alkali trace elements are, however, not markedly affected by the salinity of the irrigation water. The transition elements Cu and Zn are enriched only in the herbaceous feedstock compared to nonsaline biomass. Sulfur, chlorine, and phosphorus are markedly enriched in the saline feedstock. The ash content of toxic elements invariably exceeds the concentrations in the baseline soil for Cu, As, Se, Cd, Sb, and Pb. Compared to nonsaline biomass ashes, Cu is relatively enriched in the herbaceous feedstock ashes, As only in eucalyptus wood, and Cd, Sb, and Pb in woody feedstock. Selenium is relatively enriched in all saline feedstock. Only the concentrations of Cd in woody saline-irrigated feedstock may potentially exceed environmental guideline concentrations and may, thus, warrant caution for using saline biomass for soil amendment.

The remediation of tributyltin (TBT) by adsorption onto nFeO, activated carbon and nFeO/activated carbon composite material as a function of adsorbent dose, contact time, pH, stirring speed, initial TBT concentration and temperature was studied. The effect of temperature on kinetics and equilibrium of TBT sorption on the precursors and the composite was thoroughly examined. The adsorption kinetics is well fitted using a pseudo-second-order kinetic model, and the adsorption isotherm data of nFeO, activated carbon could be described by the Freundlich isotherm model whereas nFeO/activated carbon composite could be described by the Freundlich and Dubinin-Radushkevich isotherm models. Thermodynamic parameters (i.e. change in the free energy (∆ G°), the enthalpy (∆ H°) and the entropy (∆ S°)) were also evaluated. The overall adsorption process was endothermic and spontaneous in nature. The results obtained also showed that 99.9, 99.7 and 80.1 % TBT were removed from contaminated natural seawater by nFeO/activated carbon composite, activated carbon and nFeO, respectively.

Arsenic (As) toxicity and the effects of nitric oxide (NO), supplied as sodium nitroprusside (SNP), were analyzed in Pistia stratiotes. The plants, which were grown in nutrient solution at pH 6.5, were exposed to four treatments for 24 h: control; SNP (0.1 mg L-1); As (1.5 mg L-1); and As + SNP (1.5 and 0.1 mg L-1). As accumulated primarily in the roots, indicating the low translocation factor of P. stratiotes. The As accumulation triggered a series of changes with increasing production of reactive oxygen intermediates and damage to cell membranes. The application of SNP was able to mitigate the harmful effects of As. This attenuation was probably due to the action of the SNP as an antioxidant, reducing the superoxide anion concentration, and as a signaling agent. Acting as a signal transducer, SNP increased the activity of enzymatic antioxidants (POX, CAT, and APX) in the leaves and stimulated the entire phytochelatins biosynthetic pathway in the roots (increased sulfate uptake and synthesis of amino acids, non-proteinthiols, and phytochelatins). The As also stimulated the phytochelatins biosynthesis, but this effect was limited, probably because plants exposed only to pollutant showed small increments in the sulfate uptake. Thus, NO also may be involved in gene regulation of sulfate carriers. © 2013 Springer Science+Business Media Dordrecht.

Spring/summer surface ozone concentrations, [O3], in coastal environments were investigated: (1) by comparison of coastal and inland monitoring stations with data from a small island >5 km off the coast of southwest Sweden, (2) as a gradient from the coast towards inland in southernmost Sweden. Further, results from the chemical transport model MATCH were used to assess the marine influence on [O3]. It was hypothesised that [O3] is higher on the small island compared to the coast, especially during night and in offshore wind. Another hypothesis was that [O3] declines from the coast towards inland. Our hypotheses were based on observations that the deposition velocity of O3 to sea surfaces is lower than to terrestrial surfaces, and that vertical air mixing is stronger in the marine environment, especially during night. The island experienced 10 % higher [O3] compared to the coast. This difference was larger with offshore (15 %) than onshore wind (9 %). The concentration difference between island and coast was larger during night, but prevailed during day and could not be explained by differences in [NO2] between the sites. The difference in [O3] between the island and the inland site was 20 %. Higher [O3] over the sea, especially during night, was reproduced by MATCH. In the gradient study, [O3] declined from the coast towards inland. Both [O3] and [NO2] were elevated at the coast, indicating that the gradient in [O3] from the coast was not caused by NO titration. The conclusions were that surface [O3] in marine environments is higher than in coastal, and higher in coastal than inland areas, especially during night. © 2013 Springer Science+Business Media Dordrecht.

Oxidative degradation of ethylenediaminetetraacetic acid (EDTA) in aqueous solution at normal temperature and pressure by the bimetallic Fe–Cu was investigated in this work. The results showed that the removal efficiency of EDTA, total organic carbon (TOC), and total nitrogen (TN) could be about 95, 62.5, and 39 %, respectively, after 3-h reaction. The degradation of EDTA followed the pseudo-first-order reaction kinetics and would not be affected by the continuous use of bimetallic Fe–Cu. The degradation products were iminodiacetate, formate, and acetate determined by ion chromatogram. The effects of initial pH, initial concentration of EDTA, Cu content, Fe–Cu loading, and atmosphere were also investigated. Significantly, the bimetallic Fe–Cu process exhibited higher reactivity than ZEA process for the degradation of EDTA and it would not cause new heavy metal pollution in effluent. Reactive oxygen species (ROS) of OH was generated in situ. The evidence of oxidative degradation of EDTA was verified by electron spin resonance (ESR) spectroscopy and the product of para-hydroxybenzoic acid (p-HBA) by OH and benzoic acid (BA).

Wild birds have been shown to be significant sources of numerous types of pathogens that are relevant to humans and agriculture. The presence of large numbers of migratory birds in such a sensitive and important ecosystem as the Platte River in central Nebraska, USA, could potentially serve a significant source of bird-derived pathogens in the water/sediment and riverine environment. In 2009 and 2010, a study was completed to investigate the potential water-quality impacts of Sandhill Cranes and Snow Geese on the microbial water quality of the central Platte River during their spring migration period. Fecal material, river-bottom sediment, and water samples were collected from January through May of each year during the spring migration season of Sandhill Cranes in the Central Flyway of North America. Results indicate that several types of fecal indicator bacteria and from a range of viral, protozoan, and bacterial pathogens, Campylobacter jejuni were present in Sandhill Crane excreta, and at significantly higher frequency and densities in water and sediments when the Sandhill Cranes were present, particularly during evening roosts within the Platte River environment. Therefore, further investigation of the health significance of avian pathogens is warranted for the Platte River in Central Nebraska during migration of Sandhill Cranes and other waterfowl.

Decolorization of brilliant green (0.06 g/L), Evans blue (0.15 g/L), and their mixture (total concentration 0.08 g/L, proportion 1:1 w/w) by fungi was studied. Fungal strains [Pleurotus ostreatus (BWPH), Gloeophyllum odoratum (DCa), and Fusarium oxysporum (G1)] were used separately and as a mixture of them. Zootoxicity (Daphnia magna) and phytotoxicity (Lemna minor) changes were estimated after the end of experiment. Mixtures of fungal strains were less effective in decolorization process than the same strains used separately (as a single strains). After 96 h of experiment, living biomass of strain BWPH removed up to 95.5 %; DCa, up to 84.6 %; G1, up to 79.2 % where mixtures BWPH + DCa removed up to 74.3 %; and BWPH + G1, only up to 32.2 % of used dyes. High effectiveness of dyes removal not always corresponded with decrease of toxicity. The highest decrease of zootoxicity and phytotoxicity (from V to III toxicity class or to even nontoxic) was noticed for single strains, while no changes or slight toxicity decrease was noticed in samples with strains mixtures.

Mercury and cadmium are priority hazardous substances. Some titanosilicates have been tested for the removal of Cd²⁺ and Hg²⁺ from single solutions by ion exchange. In this work, the competition between both contaminants for the exchanger binding sites of titanosilicate Engelhard titanosilicate material number 4 (ETS-4) was studied by performing batch experiments with aqueous solutions containing the two counter ions. The results evidenced the large capacity of ETS-4 and shown that the cadmium(II) diffusivity through the sorbent is higher than that of mercury(II). Furthermore, the ETS-4 exhibited higher kinetic and equilibrium selectivities for Cd²⁺, which attained values in the ranges 8.9–12.5 and 7.9–12.8, respectively. With respect to modelling, the pseudo-second-order equation described successfully the competitive removal of Cd²⁺ and Hg²⁺.