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This study investigated for the first time the effects of ZnO nanoparticle (NP) chronic exposure (28 days) on Tigriopus fulvus. Acute toxicity (48 h) of three Zn chemical forms was assessed as well including the following: (a) ZnO nanoparticles (NPs), (b) Zn2+ from ZnO NP suspension after centrifugation (supernatant) and (c) ZnSO4 H2O. Physical-chemical and electronic microscopies were used to characterize spiked exposure media. Results showed that the dissolution of ZnO NPs was significant, with a complete dissolution at lowest test concentrations, but nano- and micro-aggregates were always present. Acute test evidenced a significant higher toxicity of Zn2+ and ZnSO4 compared to ZnO NPs. The chronic exposure to ZnO NPs caused negative effects on the reproductive traits, i.e. brood duration, brood size and brood number at much lower concentrations (≥ 100 μg/L). The appearance of ovigerous females was delayed at higher concentrations of ZnO NPs, while the time required for offspring release and the percentage of non-viable eggs per female were significantly increased. ZnO NP subchronic exposure evidenced its ability to reduce T. fulvus individual reproductive fitness, suggesting that ZnO NPs use and release must be carefully monitored. [Figure not available: see fulltext.]

Nonylphenol ethoxylated (NPEOs) nonionic surfactants have been increasingly used in different industrial, commercial and domestic applications. Unfortunately, they are classified as endocrine disrupting chemicals (and also considered as contaminants of emerging concern) having adverse effects on animal and human reproduction. The treatment of nonylphenol-decaethoxylated (NP-10) via H2O2/UV-C process at different reaction times (5, 10, 20, 40, 80 min) and H2O2 concentrations was investigated. After 80 min treatment the removal rates of NP-10 solution (initial concentration 100 mg/L) in deionized water were 88%, 97% and 98% for 10, 20 and 100 mg/L of H2O2 respectively. The same experimental conditions were applied to real wastewater spiked with 100 mg/L of NP-10 showing the following removal rates: 84%, 98% and 99%, respectively. The possible contribution of different radicals to NP-10 degradation by H2O2/UV-C treatment was investigated by evaluating the effect of different radical scavengers (namely NO3−, NaCl, Na2SO4, Na2CO3, KH2PO4 and phatalate). Toxicity data (Aliivibrio fischeri, Raphidocelis subcapitata and Daphnia magna) on treated solutions and wastewater highlighted the presence of residual toxicity in all samples evidencing that no complete mineralization occurred.

The release of antibiotics in aquatic ecosystems from the effluents of wastewater treatment plants (WTPs) is of great concern due to possible chronic toxic effects as well as contribution to antibiotic resistance spread. In the present work, the degradation of the antibiotic chloramphenicol (CAP) by ultraviolet (UV)/peracetic acid (PAA) (an advanced oxidation process that has been poorly investigated so far) and UV/H2O2 processes as well as its transformation products were studied under different light sources. UV-C/PAA process was found to be effective in the degradation of CAP (half life time (t1/2) = 20 min, initial CAP concentration 25 mg/L), but not effective when solar radiation was used as light source. It is worthy to note that the presence of H2O2 in the commercial PAA solution significantly affected the removal efficiency of CAP by UV-C/PAA process. When H2O2 was quenched by catalase addition, t1/2 increased to 99 min, meaning that PAA can still produce hydroxyl radicals but at a lower rate compared to H2O2. Moreover, process efficiency further decreased in the presence of both solar simulated and natural solar irradiation, being CAP removal also the result of thermal decomposition. The transformation products detected during CAP degradation by UV-C/PAA were different respect to those produced during UV-C/H2O2 process. In particular, after 120 min most of the compounds detected presented a molecular weight >300 m/z., meaning that UV-C/PAA process needs more time to degrade the transformation products.

Contaminants of emerging concern (CECs) occur in the environment on a global scale and encompass a huge number of life style compounds, ranging from organic and inorganic compounds to nanoparticles, released into the environment because of human activities with the potential to harm biota and health. Owing to their extensive application, their continuous occurrence and release in wastewaters, sewage sludge, surface water and groundwaters, landfills, and waste have become an emerging issue to consider control measures for them. Urban Wastewater Treatment Plants are one of the main point sources of CECs to the environment as UWWTPs are usually not designed to effectively remove them. Although improvement of analytical techniques allowed the identification of widespread CECs in reduced concentrations (μg to ng/L) and in various environmental compartments, we are still far away from a complete classification of many CECs and their potential harmful effects. Therefore, providing data on occurrence, sources, and fate of CECs is essential for prioritizing and regulating them.

Most studies investigating the toxicity of zinc oxide nanoparticles (ZnO NPs) focused on the effect of size, whereas exposure concentration and duration remained poorly understood. In this study, the effect of acute and sub-acute exposures of ZnO NPs on Zn compartmentalization and biomarkers' expression were investigated in Rutilus rutilus caspicus (Caspian roach) considering various exposure scenarios: i) the assessment of the concentration-response curves and median lethal concentration (LC50); ii) the assessment of the effects of organisms exposed at LC50 value and one tenth of LC50 value of ZnO NPs suspensions for 4 d and 28 d, respectively; iii) the assessment of 14 d depuration period. The same concentrations of ZnSO4 were investigated. The highest Zn accumulation was detected in gill after sub-acute exposure (4.8 mg/L; 28 d) followed by liver, kidney and muscle. In gill, liver and muscle, Zn from Zn NPs accumulated higher concentrations. Depuration (14 d) decreased Zn content in each organ, but no complete removal occurred except for muscle. Biomarkers' activity was significantly over expressed after treatments, but depuration brought back their values to background levels and most effects were related to acute concentrations (48 mg/L; 4 d) and in presence of ZnSO4. Histopathological analyses showed that the exposure to ZnO NPs increased lesions in gill, liver and kidney, with a direct proportionality between alterations and Zn accumulated in the target organs. After depuration, lesions regressed for both ZnO NPs and ZnSO4, but not in a complete way. These data could contribute to increase the knowledge about ZnO NPs risk assessment in aquatic vertebrates, suggesting that the size of ZnO NPs can influence biomarker and histopathological effects.

The Sarno River is considered the most polluted river in Europe and one of the ten most polluted rivers in the world. So far, its quality has been usually evaluated by water and sediment analyses of either inorganic or organic pollutants. However, a biomonitoring approach would be of paramount importance in the evaluation of river quality, since it integrates pollutant temporal fluctuations, as in the case of discontinuous inputs from urban, industrial and agricultural activities. To this end, a passive biomonitoring study of the Sarno River was carried out, using two native aquatic plants accumulators of inorganic pollutants. The spring area was monitored analysing the roots of the semi-submerged Apium nodiflorum, whereas the whole river course was monitored analysing the shoots of the submerged Potamogeton pectinatus. The information on the four macronutrient (Ca, K, Mg, P), the six micronutrient (Cu, Fe, Mn, Na, Ni, Zn) and the four toxic element (Cd, Cr, Pb, V) concentrations were separately combined in the Nemerow Pollution Index. Results evidenced a severe pollution degree of the Sarno River, attributable to toxic elements > micronutrients > macronutrients. In particular, the spring area showed high K concentrations, as well as high concentrations of several micronutrients and toxic elements. A generalized Zn contamination and a progressive macronutrient (above all Ca and P), micronutrient (above all Ni, Cu and Fe) and toxic element (above all Cr and Pb) accumulation toward the mouth was related to pollution from agricultural and urban activities. Industrial sources, especially tanneries along the Solofrana tributary, accounted for high Mn concentrations, whereas the volcanic origin of the substrate accounted for a generalized V contamination.

Antibiotics are emerging pollutants released into the environment through wastewater and manure or effluents from livestock plants. Compared to the wide literature on the effects of antibiotics on the development of drugresistant bacteria and on the adverse effects on animals and human beings, the effects on plants are less investigated. Here we evaluated the effects of four antibiotics (cloramphenicol: CAP, spiramycin: SPR, spectinomycin: SPT, vancomycin: VAN) belonging to different chemical groups, on seed germination and root development of tomato (Solanum lycopersicum L. cv. San Marzano). Specifically, seed germination and root elongation kinetics, as well as the number of mithotic figures in root apical meristem, were studied in relation to different concentrations of each antibiotic (0, 0.1, 1, 10, 100, 1000 mg L−1) for 10 and 7 days, respectively. Results showed that seed germination was not affected, but root development (root elongation kinetics and cell division) was impaired at concentrations from 10 mg L−1 (SPT) and 100 mg L−1 (CAP) to 1000 mg L−1 (SPR and VAN).

Thirty contaminants of emerging concern (CECs) were identified and quantified in hospital wastewater (HWW) by LC-MS and their removal by solar photo Fenton (SPF) with ethylenediamine-N,N’-disuccinic acid (EDDS) at spontaneous pH (7.5) was compared to other solar driven advanced oxidation processes (AOPs) (namely, sunlight/persoxydisulphate (SPD) and sunlight/H2O2 (SHP)). Almost all the detected CECs (28) are pharmaceuticals and belong to 13 different classes, with concentrations varied between 0.08 µg/L (psychiatric drug) to 38.92 µg/L (antidiabetic). First, the formation of iron-EDDS complexes was characterized by electrochemical methods to compare Fe2+ and Fe3+ behavior. The effect on a carbamazepine (CBZ) aqueous solution of solar driven Fe2+/EDDS and Fe3+/EDDS Fenton processes was comparatively evaluated to select the most effective one for advanced oxidation tests on real HWW and sunlight/Fe2+-EDDS/H2O2 was the most effective one with 48% removal after 12.5 kJ/L-1 (78% total removal, 30% being under dark Fenton condition). SPF process was also more effective than SPD and SHP (60 min sunlight exposure, 5 kJ/L-1). Subsequently, the effect of the solar AOPs (SPF, Fe2+ 0.1 mM, EDDS 0.2 Mm, H2O2 2.7 Mm; SPD, PD 1.48 mM; SHP, H2O2 2.7 Mm; 60 min sunlight exposure) was investigated in the treatment of the HWW and SPF resulted the most effective one, all CECs being removed from 70% to 100%.

Contaminants of emerging concern (including pharmaceuticals) are not effectively removed by municipal wastewater treatment plants (WWTPs), so particular concern is related to agricultural wastewater reuse due to their possible uptake in crops irrigated with WWTPs effluents. Advanced oxidation processes (AOPs) and solar AOPs have been demonstrated to effectively remove pharmaceuticals from different aqueous matrices. In this study, an heterogeneous photocatalytic process using powdered nitrogen-doped TiO2 immobilized on polystyrene spheres (sunlight/N–TiO2) was compared to the benchmark homogenous AOP sunlight/H2O2 in a compound triangular collector reactor, to evaluate the degradation of three pharmaceuticals (carbamazepine (CBZ), diclofenac (DCF), trimethoprim (TMP)) in water. The degradation of the contaminants by sunlight and sunlight-AOPs well fit the pseudo-first order kinetic model (but for TMP under sunlight). High removal efficiency by solar photolysis was observed for DCF (up to 100%, half-life sunlight cumulative energy QS,1/2 = 2 kJ L−1, half-life time t1/2 = 32 min), while CBZ (32%, QS,1/2 = 28 kJ L−1, t1/2 = 385 min) and TMP (5% removal after 300 min) removal was poor. The degradation rate of CBZ, TMP and DCF was found to be slower during sunlight/H2O2 (QS,1/2 = 5 kJ L−1, t1/2 = 77 min; QS,1/2 = 20 kJ L−1, t1/2 = 128 min; QS,1/2 = 4 kJ L−1, t1/2 = 27 min, respectively) compared to sunlight/N–TiO2 (QS,1/2 = 4 kJ L−1, t1/2 = 55 min; QS,1/2 = 3 kJ L−1, t1/2 = 42 min; QS,1/2 = 2 kJ L−1, t1/2 = 25 min, respectively). These results are promising in terms of solar technology upscale because the faster degradation kinetics observed for sunlight/N–TiO2 process would result in smaller treatment volume, thus possibly perspective compensating the cost of the photocatalyst.

Textile dyes and their residues gained growing attention worldwide. Textile industry is a strong water consumer potentially releasing xenobiotics from washing and rinsing procedures during finishing processes. On a decentralised basis, also final consumers generate textile waste streams. Thus, a procedure simulating home washing with tap water screened cotton textiles leachates (n = 28) considering physico-chemical (COD, BOD5, and UV absorbance) and ecotoxicological data (Daphnia magna, Pseudokirchneriella subcapitata and Lepidium sativum). Results evidenced that: (i) leachates presented low biodegradability levels; (ii) toxicity in more than half leachates presented slight acute or acute effects; (iii) the remaining leachates presented “no effect” suggesting the use of green dyes/additives, and/or well established finishing processes; (iv) no specific correlations were found between traditional physico-chemical and ecotoxicological data. Further investigations will be necessary to identify textile residues, and their potential interactions with simulated human sweat in order to evidence potential adverse effects on human health.

Polluted sediment represents a great problem for aquantic environments with potential direct acute and chronic effects for the biota and can be tackled with both in situ and ex situ treatments. Once dredging activities are not compulsory, sediment can be kept in place and managed with techniques involving the use of amendment and/or capping. Before their application, the assessment of their potential impact to the target environment cannot ignore the safe-by-design approach. The role of toxicity in in situ sediment remediation was reviewed discussing about how it can be used for the selection of amendments and the monitoring of treatment technologies. Results evidenced that capping technology coupled to activated carbon (AC) is the most frequently applied approach with effects varying according to the rate of contamination in treated sediment, the amount of AC used (% v/v), and target biological models considered. Little data are available for zerovalent iron as well as other minor amending agents such as hematite, natural zeolite, biopolymers and organoclays. Current (eco-)toxicological information for in situ sediment remediation technologies is fragmentary and incomplete or entirely missing, making also the interpretation of existing data quite challenging. In situ sediment remediation represents an interesting potentially effective approach for polluted sediment recovering. As its application in some lab-based and field studies reported to induce negative effects for target organisms, amendments and capping agents must be attentively evaluated for short- and long-term environmental effects, also in the perspective of the remediated site monitoring and maintenance.

In this paper, a modeling study focused on optimizing the PAA disinfection performance in a full-scale contact tank currently operated at the Nocera (Italy) Wastewater Treatment Plant is presented. The disinfection process was monitored for over 2 weeks by collecting full-scale data on plant variability in flow, disinfectant demand/decay and microbial concentrations. A computational fluid dynamics (CFD) model of the contact tank describing the PAA disinfection process was developed. Four disinfection scenarios were analysed using an Eulerian-Lagrangian approach: (a) PAA disinfection under the existing conditions; (b) PAA disinfection with PAA pre-mixed prior to the contact tank; (c) PAA disinfection with PAA dosed with 8 injection points distributed over the entire length of the inlet weir; (d) PAA disinfection in an optimized plug-flow contact tank. All these scenarios were analysed for the same operating conditions, i.e. fixed flow, PAA demand/decay and inactivation kinetics. The model-based analysis clearly revealed that the optimized contact tank (scenario d) was able to achieve a much higher contact and extended between microorganisms and disinfectant thus resulting into a five-fold increase in microbial inactivation.

The removal of emerging contaminants from wastewater is urgently required and even more necessary for wastewater reuse. Since conventional WWTPs are not designed to treat water polluted with pharmaceuticals present at trace levels, the applied treatments are mostly ineffective in their removal. Therefore the use of more efficient processes for removing or improving the biodegradability of these compounds has become necessary. Among several advanced oxidation process, nano based photocatalytic processes represent a challenging alternative for pharmaceuticals removal due to its capacity to utilize the solar radiation as the light source, thus reducing significantly electric power required and therefore saving treatment costs and to operate without pH adjustment. This chapter is aimed at describing the state of the art in the heterogeneous photocatalytic degradation of pharmaceuticals using different nano particles (NPs).

The self-assembling of fluorescent guest molecules, with the δ nanoporous host crystalline phase of syndiotactic polystyrene (s-PS) films, reduces chromophore diffusivity. Moreover, the chromophore...

The Sarno River trend analysis during the last 60 years was traced focusing on the socio-economic and environmental issues. The river, originally worshiped as a god by Romans, is affected by an extreme level of environmental degradation, being sadly reputed as the most polluted river in Europe. This is the “not to be followed” example of the worst way a European river can be managed. Data about water, sediment, soil, biota and air contamination were collected from scientific papers, monitoring surveys, and technical reports depicting a sick river. Originally, the river was reputed as a source of livelihood, now it is considered a direct threat for human health. Wastewater can still flow through the river partially or completely untreated, waste production associated with the manufacture of metal products and leather tanning continues to suffer from the historical inadequacy of regional wastewater treatment plants (WWTPs), associated with the partial or no reuse of effluents. All efforts should be devoted to solving the lack of wastewater and waste management, the gap in land planning, improving the capacity of existing WWTPs also via the construction of new sewer sections, restoring Sarno River minimum vital-flow, keeping to a minimum uncontrolled discharges as well as supporting river contracts. The 2015 goal stated by the Water Framework Directive ( 2000/60/EC ) is still far to be reached. The lesson has not been learnt yet.

Tannery wastewater is considered to be one of the most polluting effluents due to it containing a large variety of toxic heavy metals that range from chromium, cadmium, cobalt, lead, nickel, selenium to arsenic. As consequence of most tannery wastewater treatments, the tannery sludge that is produced contains considerable amounts of heavy metals, which are harmful to the environment and human health. Hence, tannery wastewater and sludge treatments have become a serious environmental issue. At present, the conventional options for sewage sludge disposal, such as fertilizers and soil amendment materials for the land and landfill, are widely applied. However, heavy metals in the tannery sludge often outweigh the soil's heavy metal content, and the application of sludge can indeed increase the concentration of heavy metals in the agricultural soil and affect the crop production owing to uptake of the metals. Research on devising appropriate treatment technologies for tannery wastewaters has gone through various phases of development over the past decades following developments in processes related to the leather manufacturing industry. This chapter attempts to revise environmental concerns and future challenges related to the management of tannery wastewater and sludge.

Arsenic (As) contamination, especially in groundwater, has been receiving increasing attention in recent years due to its adverse effects on human health and the environment. Its biogeochemical cycle involves several physico-chemical processes as well as biological mechanisms, in which microorganisms play a key role. The inorganic compounds arsenite [As(iii)] and arsenate [As(v)] are the most toxic and abundant species of arsenic in water. Depending on the environmental physico-chemical condition these compounds have a relatively high solubility and are readily transported through aqueous routes into the environment, transferred from soils to crops and accumulated in various food crops and aquatic plants, threating human health. According to recent studies rice may be the primary source of inorganic arsenic for human exposure. In this chapter sources, pathways and levels of arsenic are presented to address the problem of its contamination of the environment. Furthermore, the state-of-the-art treatment of arsenic-contaminated waters, including a variety of treatment technologies based on oxidation, coprecipitation, adsorption, ion exchange and membrane and bio-processes are reported. The efficiency and applicability/appropriateness of the technologies have been evaluated, with regard to influent arsenic concentration, differences in source water composition, production of toxic sludge, economical aspects and social acceptance.

The molecular structure of the title compound, C(12)H(15)NO(4), has several features related to steric hindrance due to the ester and dimethylamine groups being located ortho with respect to one another. In particular, the carbonyl group of the ester is not coplanar with the ring, the amine N atom is in a pyramidal arrangement [the N atom is 0.2161 (12) A from the three C atoms to which it is bonded] and the C atom of the adjacent ester group lies 0.3784 (14) A out of the plane of the aromatic ring. The deformations found in the X-ray structure have been confirmed by ab initio quantum mechanical calculations.

The polymorphic behavior of the polyester [(CH 2 ) 12 OCOPhCOOPh(CH 3 )OCOPhCOO] n consisting of an aromatic triad mesogen and a flexible spacer has been investigated. The effect of thermal and mechanical treatment on the appearance of two crystalline phases stable at room temperature is discussed. The molecular packing (triclinic cell, space group P1) and the morphological parameters of the crystalline phase stabilized by drawing process are evaluated and refined. The whole-pattern method, based on the analysis of the whole x-ray diffraction pattern from fiber samples of polymer, has been employed. The molecular packing resembles very much that of polyethylene terephthalate

The syndiotactic polystyrene shows a complex polymorphism, and the structural organization depends on thermal or solvent treatments. The effect of different solvents on oriented samples crystallized in a zigzag conformation has been investigated, and in some cases a transition to the helix conformation is observed. The obtained results show that the transition occurs through an intermediate amorphous state in which the molecular orientation is maintained. This evidence points to the conclusion that some kind of noncrystalline order is present in the intermediate swollen state

The molecular structure of the crystalline phase of the thermotropic main-chain polyester known as C 12 αMS, stable at 175 o C, has been determined by fiber X-ray diffraction using the whole-pattern method. The polymer has a complex polymorphism, and the phase characterized is the one stable just below the transition to the nematic state. The unit cell is monoclinic, P2 1 /a space group with two repeat unit C 14 H 16 O 2 per cell. Lattice constants are a= 13.83(1) A, b= 5.28(1) A, c= 27.3 A and β= 138.6°

The effect of complementary base pairing on the oxidation potential of a guanosine derivative has been determined by cyclic and differential pulse voltammetry in CHCl3. The formation of the Watson-Crick H-bonded complex lowers the oxidation potential of the free molecule by 0.34 V, which compares well with the value obtained by DFT/B3LYP/6-311++g** computations.

The photophysics of free-base hemiporphyrazine has been studied by theoretical computations based on time dependent density functional theory and multiconfigurational complete active space methods. The results confirm that the dual emission spectrum of hemiporphyrazine is due to the formation at the excited state of different tautomers, but the emission at longer wavelength, originally attributed to a vibronically induced radiative decay from the tautomer with both central hydrogens linked to pyridine rings, is now ascribed to a dipole allowed transition, occuring either from that tautomer or from the tautomer with the two hydrogens linked to one pyridine and one isoindole ring.

We have prepared Bi2Sr2CaCu2O8−δ/Bi2Sr2YCu2O8−δ/Bi2Sr2CaCu2O8−δ trilayer structures, using an in situ DC‐sputtering process at high oxygen pressures on (001) SrTiO3 substrates. Bi2Sr2CaCu2O8−δ films were used for superconducting electrodes and semiconductor‐like Bi2Sr2YCu2O8−δ films with thicknesses between 5 and 30 nm were used as barrier layers. The composition of the barrier except for Y, as well the structure are compatible with those of the superconducting electrodes which allowed the epitaxial growth of the heterostructure as shown by X‐ray and cross section Transmission Electron Microscopy (TEM) analysis. Gap‐like structures have been observed in the tunneling characteristics of the junctions, flat and linear conductance background as well as a zero‐bias conductance peak, have been observed too.

A systematic study of yttrium substitution for calcium in the high-temperature superconductor Bi2Sr2CaCu2O8 compound has been performed. The samples of Bi2Sr2YxCa1−xCu2O8 have been prepared by the sintering standard procedure using oxides and carbonates as precursors, weighted to obtain the nominal composition with 0≤x≤1. The real stoichiometric composition of the pellets and uniformity of the samples has been verified by EDS analysis. The grain dimension (≈1 μm) and the good pellet compactness have been established by SEM morphologic observation. By X-ray diffraction analysis the crystalline structure of orthorhombic type has been established. By increasing the yttrium concentration the resistivity dependence on temperature goes from metallic to insulating behaviour. For the superconductive samples Tc decreases for increasing doping percentage. «Thick» films on MgO substrates of Bi2Sr2CaCu2O8 have been obtained by melting-quenching-annealing procedure. These films showed critical temperatures higher than the pellets.

[Cu(C 22 H 26 NO 4 ) 2 ] cristallise dans P1 - avec a=10,866, b=11,307, c=8,768 A, α=106,37, β=90,32, γ=97,34°, Z=1; affinement jusqu'a R=0,085. Le complexe est plan carre trans. La molecule a la symetrie Ci et une forme plate. L'angle diedre entre le groupement plan salicylideneaminato et le groupement ethyle lie a N est de 89,3°. Le groupement plan salicylideneaminato et le groupement benzyloxy sont tordus a 57,1°

The fabrication procedure of “bulk” junctions based on sinterized YBCO samples with a Ta 2 O 5 barrier and a Pb counterelectrode is described. The derivative dl/dV vs. V curves show in most samples a gap structure varying between 15–20 meV. Moreover narrow resistance peaks that vary from sample to sample and on thermal cycling are found. Probably these structures can be ascribed to the granular nature of the YBCO electrode.