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Waterborne pathogens represent one of the most widespread environmental concerns. Conventional disinfection methods, including chlorination and UV, pose several operational and environmental problems; namely, formation of potentially hazardous disinfection by-products (DBPs) and high energy consumption. Therefore, there is high demand for effective, low-cost disinfection treatments. Among advanced oxidation processes, the photocatalytic process, a form of green technology, is becoming increasingly attractive. A systematic review was carried out on the synthesis, characterization, toxicity, and antimicrobial performance of innovative engineered photocatalysts. In recent decades, various engineered photocatalysts have been developed to overcome the limits of conventional photocatalysts using different synthesis methods, and these are discussed together with the main parameters influencing the process behaviors. The potential environmental risks of engineered photocatalysts are also addressed, considering the toxicity effects presented in the literature.

The intensive human activities extensively contaminated water sources making its treatment a problem of paramount importance, especially with the increasing of global population and water scarcity. The application of natural coagulants has become a promising and environmentally friendly alternative to conventional ones. This study was aimed at evaluating the efficiency of four plant extracts namely Agave americana, Carpobrotus acinaciformis, Austrocylindropuntia subulate, and Senicio anteuphorbium as natural coagulants to remove Microcystis aeruginosa cyanobacterium from water. The effects of pH (4, 5, 6, 7, 8 9, and 10) and coagulant dose (5, 10, 15, 20, 25, and 30 mg/L) on the coagulation efficiency were investigated. Results showed that plant-based extracts exhibited high coagulant abilities significantly contributing to the removal of M.aeruginosa cells up to 80% on a case-by-case basis. The ecotoxicity (Daphnia magna, Aliivibrio fischeri, Raphidocelis subcapitata, and Sorghum saccharatum) was absent or presented very slight acute toxicity up to 12.5mg/L being S.anteuphorbium the least toxic. PRACTITIONER POINTS: Nature-based plant extracts showed removal rates up to 80%. Lower pH and A.subulate and S.anteuphorbium were the most efficient coagulants Toxicity effects were plant extracts-based and dose function. A.subulate and S.anteuphorbium were the least toxic extracts.

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.

The removal of contaminants of emerging concern from urban wastewater treatment plants (WWTPs) remains a challenge to promote safe wastewater reuse practices. Macrolides are the most abundant antibiotics detected in untreated wastewater and their concentration in WWTPs effluents is only partially reduced by conventional treatments. Among several advanced oxidation processes (AOPs), photocatalysis has demonstrated the capability to effectively remove pharmaceuticals from different aqueous matrices. Recently, ZnO has emerged as an efficient, promising, and less expensive alternative to TiO2, due to its photocatalytic capability and attitude to exploit better the solar spectrum than TiO2. In this study, the behaviors of ZnO photocatalysis were evaluated using a representative macrolide antibiotic, spiramycin (SPY), in aqueous solutions and urban wastewater. After 80 min of photocatalysis, 95–99% removal of SPY was achieved at 1 g L−1 ZnO concentrations in aqueous solutions and wastewater, respectively. After treatment, the effluent toxicity, evaluated using the bacterium Aliivibrio fischeri, the green alga Raphidocelis subcapitata, and the crustacean Daphnia magna ranged between slight acute and high acute hazard. Filterable and ultrafilterable Zn concentrations were quantified in treated effluents and shown to be high enough to contribute to the observed toxicity.

This study investigated sediment spatial and seasonal distribution of trace elements (TEs) (n = 16) and human health effects along the Hooghly River Estuary (India). The index of geo-accumulation (Igeo), enrichment factor (EF), hazard quotient (HQ), modified hazard quotient (mHQ) and toxic risk unit (TRI) were calculated to estimate sediment pollution level, while hazard index (HI) and lifetime cancer risk (LCR) were used to assess TEs enrichment vs. human health. The concentrations (&micro, g/g dry weight) of TEs were: Cd (0.01&ndash, 1.58), Cr (41.98&ndash, 105.49), Cu (16.41&ndash, 51.09), Ni (28.37&ndash, 63.90), Fe (22075&ndash, 47919), Mn (423&ndash, 630), Co (11.43&ndash, 23.11), Zn (48.82&ndash, 105.81), V (63.92&ndash, 138.92), Pb (25.01&ndash, 43.27) and Ti (0.18&ndash, 3.50), As (2.92&ndash, 16.26), B (59.34&ndash, 98.78), Si (11.52&ndash, 98.78), Be (1.71&ndash, 4.81), Ba (95.23&ndash, 293.72). From Igeo and EF, Cd was the major contaminant, while Ni presented moderate/high contamination (HQ and TRI). Children were more exposed to carcinogenic and non-carcinogenic risks compared to adults. For non-carcinogenic substances, no significant risk was found to both children and adults (HIs &lt, 1). The LCR for Cr (3.924 &times, 10&minus, 4 for children) and As (1.379 &times, 4 for children) was higher than the threshold limit value (TLV, 10&minus, 4 and 10&minus, 6) indicating significant carcinogenic risks to be managed.

Solar driven advanced oxidation processes (AOPs) (an alternative solar photo Fenton like process (SPF), sunlight/H2O2 (SHP) and sunlight/chlorine (SCL)) and respective dark conditions, were compared for the first time to conventional (chlorination and UV-C radiation) disinfection processes, in the inactivation of E. coli and Entero strains inoculated in real roof-harvested rainwater (RHRW), to evaluate their possible safe use for crop irrigation. In this regard, bacterial regrowth was also evaluated 6, 12, 24 and 48 h after disinfection treatment. The SPF, using iminodisuccinic acid (IDS)-Cu complex as catalyst, was optimized (H2O2/IDS-Cu 55/1 best molar ratio) under mild conditions (spontaneous pH) and sunlight. The faster inactivation kinetics were observed for the SCL process (k = 1.473 min−1, t1/2 = 0.47 min for E. coli and k = 1.193 min−1, t1/2 = 0.57 min for Entero), while the most effective processes in controlling bacterial regrowth were SPF and SCL. Although UV-C radiation (0–1.3 × 104 μW s cm−2 dose range) was the second faster disinfection process (k = 1.242 min−1, t1/2 = 0.55 min for E. coli and k = 1.150 min−1, t1/2 = 0.60 min for Entero), it was the less effective process in controlling bacterial regrowth (>10 CFU 100 mL−1 already after 6 h post-treatment incubation). According to the bacterial inactivation and regrowth tests carried out in this work, SPF and SCL are interesting options for RHRW disinfection, in case of effluent use for crop irrigation.

Conventional fertilization practices in agroecosystems concern the supply of bioavailable nutrients, such as mineral fertilizers. A consolidated alternative to restoring the long-term fertility of agricultural soils is their amendment with organic fertilizers. Soil amendment with biowaste compost or sewage sludge represents a sustainable strategy to avoid the landfilling of organic matter derived from urban waste and sewage sludge. This study aims at validating the use of quality biowaste compost and sewage sludge from secondary sedimentation (alone or in combination with mineral fertilizers) in a Mediterranean agroecosystem and their effects on soil chemical and biological quality, with a view to verifying the maintenance of soil fertility and functionality. In particular, the dynamics of soil organic matter, pH, potentially toxic elements and microbial community functionality were assessed, in experimental mesocosms, during 6 months of incubation. The research showed that, while soil amendment with biowaste compost induces positive effects on soil organic matter and phosphorous concentrations, as well as on microbial community functionality, the amendment with the selected sewage sludge does not determine any benefit to the microbial community or any danger in relation to soil potentially toxic element concentrations and toxicity. The quantity of sewage sludge employed, chosen according to regional directives, was thus not enough to stimulate the edaphic microflora activity.

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.

A continuous flow photocatalytic packed-bed reactor irradiated by UV-LEDs was employed for the degradation of two toxic anionic azo dyes: Eriochrome Black-T (EBT) and Methyl Orange (MeO). Commercial anatase TiO2 in pellets form was used as packing material for the photoreactor. The experimental tests were carried out using both distilled and tap water as aqueous matrix for the two selected dyes. The influence of the liquid flow rate on the performances of the photocatalytic packed-bed reactor was investigated in the range 0.5–2.1 mL/min. Photocatalytic results showed that, under UV light, the system allows to achieve steady-state dyes concentration values without deactivation phenomena in 510 min irradiation time. Using distilled water, the highest efficiency of the process (EBT and MeO decolorization of about 100 % and 90 %, respectively) was observed with a liquid flow rate of 0.5 mL/min (contact time =6.6 min). In the presence of tap water and using the same contact time, the EBT decolourization was still total whereas MeO degradation was lower and equal to 70 %. For this reason, the photocatalytic reactor was followed by an adsorption unit based on the use of activated carbon. With such configuration, the complete MeO decolourization was achieved. The total removal of toxicity for EBT was achieved with just one packed-bed reactor being the toxicity of potential by-products not relevant. In the case of MeO, the full toxicity removal was obtained only after powdered activated carbon filtration.

Textile wastewaters contain refractory dyes that cause pollution and socio-economic issues, thus calling for efficient remediation techniques such as photocatalysis. We review the fabrication, functionalization, performance and limitations of doped catalysts for degrading and mineralizing dyes. We present developments in photocatalyst immobilization and photocatalytic reactor design. Methods such as microwave irradiation, sonication and use of ionic liquids are emerging for the preparation of doped photocatalysts. Whilst single-dye systems have been extensively studied, there is limited knowledge on multiple-dye systems. Immobilization of photocatalysts is gaining popularity for large-scale application, but faces issues of erosion, corrosion, mechanical strength and structure integrity. Ecotoxicological studies are required in real environments to validate the potential applications of nanostructured doped photocatalysts.

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%.

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.

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.

Year-by-year, the amount of antibiotics for human and veterinary use increases. Their presence in both treated and untreated wastewater was highlighted in several studies, suggesting that traditional activated sludge processes are unsuitable for their efficient removal. In this review paper, we summarized the role of advanced oxidation processes (AOPs) in antibiotics removal evidencing their pros, cons and limitations. In most cases, they are still applied at laboratory or pilot scale, with just few examples of full-scale applications. Main constraints are related to energy cost, catalyst management and potential residual toxicity in treated effluents. The main advantages are related to the full mineralization of target compounds or the ability to increase their relative biodegradability. Future challenges include nano-based green synthetized catalysts maximizing the use of solar radiation for energy saving. Generally, AOPs application is part of a more structured wastewater treatment process including operating units at various technological contents.

The fate of indigenous surface-water and wastewater antibiotic resistant bacteria in a mild slope stream simulated through a hydraulic channel was investigated in outdoor experiments. The effect of (i) natural (dark) decay, (ii) sunlight, (iii) cloudy cover, (iv) adsorption to the sediment, (v) hydraulic conditions, (vi) discharge of urban wastewater treatment plant (UWTP) effluent and (vii) bacterial species (presumptive Escherichia coli and enterococci) was evaluated. Half-life time ( T 1/2 ) of E. coli under sunlight was in the range 6.48–27.7 min (initial bacterial concentration of 10 5 CFU/mL) depending on hydraulic and sunlight conditions. E. coli inactivation was quite similar in sunny and cloudy day experiments in the early 2 hr, despite of the light intensity gradient was in the range of 15–59 W/m 2 ; but subsequently the inactivation rate decreased in the cloudy day experiment ( T 1/2 = 23.0 min) compared to sunny day ( T 1/2 = 17.4 min). The adsorption of bacterial cells to the sediment (biofilm) increased in the first hour and then was quite stable for the remaining experimental time. Finally, when the discharge of an UWTP effluent in the stream was simulated, the proportion of indigenous antibiotic resistant E. coli and enterococci was found to increase as the exposure time increased, thus showing a higher resistance to solar inactivation compared to the respective total populations.

A continuous flow micro-reactor irradiated by UV-LEDs was employed to treat coloured wastewater by adsorption and simultaneous photocatalysis. Zinc oxide (ZnO) immobilized on commercial zeolites pellets in spherical shape (ZEO) was used as catalytic material in a micro-reactor maximizing the photocatalyst exposition to light sources, irradiating uniformly the entire solution volume and improving the mass transfer phenomena. Experimental tests were carried out on crystal violet dye (CV) as one of the main dying agent present in textile wastewater. The comparison between adsorption and adsorption/photocatalytic tests showed that UV irradiation can achieve a steady state CV concentration value corresponding to an equilibrium condition between adsorption and photocatalytic oxidation. The higher removal efficiency (i.e. 93%) was observed with a liquid flow rate of 1.1 mL/min (contact time = 4.7 min; CV = 10 mg/L) under UV light irradiation. In the steady state, CV removal remained constant for the overall testing time. Bioassays evidenced that toxicity was not completely removed (i.e. final effluent ranked as “slight acute toxic”) from wastewater suggesting its suitability for sewage collection discharge. A Dubinin Radushkevich (D-R) isotherm model was applied for studying the adsorption behaviour of ZnO/ZEO sample. CV adsorption constants were evaluated from experimental data carried out in dark conditions in a batch system. Kinetic expression of CV removal and the D-R adsorption were incorporated in the CV mass balance estimating the kinetic parameter. The model was validated comparing the calculated CV conversion with the experimental tests collected at different CV inlet concentration.

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.

A multistep methodology for the evaluation of the energetic behaviour of a wastewater treatment plant has been carried out, in according to Horizon2020 Enerwater methodology. The study took into account each phase of the process scheme, in order to obtain specific electricity consumption values for all the electro-mechanic devices. Data from both tele-control system and direct measurements in field have been acquired in order to perform a critical analysis for improving energy efficiency.

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).

It has been said that Palermo is short of available water. However, nothing could be more wrong. Well-documented Arab sources and narrative chronicles reported an abundance of groundwater resources in Palermo Plain since the Middle Ages. The scarcity of sources and surface water in the Palermo Plain, compared to the groundwater abundance, led the inhabitants to use groundwater both for irrigation and domestic usage through a complex and sustainable hydraulic system. Vertical and horizontal (qanāts) wells, conveyed water towards gardens and public fountains making the Arabic Bal’harm (Palermo) a flourishing town. When visitors walk through the streets of Palermo’s historical center, among Arab ruins and Baroque architecture, they hardly imagine that there is a wide and varied cultural heritage of underground cavities hidden in the basements where water flows in intricate networks fed from a numerous springs. Only in recent years was a part of this system brought to light. Moreover, the city still has a wide and fascinating water distribution system consisting of irrigation basin (gebbie), ingenious hydraulic machines named senie, and distribution chessboard of irrigation (saje) and drinking water (catusi) canals. The medieval water collection and distribution systems and their various components in the Palermo Plain are reviewed together with the influence of the Arab water management on environment.

Chloramphenicol sodium succinate (CAP, C15H15Cl2N2 Na2O8) is a broad-spectrum antibiotic exhibiting activity against both Gram-positive and Gram-negative bacteria as well as other groups of microorganisms only partially removed by conventional activated sludge wastewater treatment plants. Thus, CAP and its metabolites can be found in effluents. The present work deals with the photocatalytic degradation of CAP using TiO2 as photocatalyst. We investigated the optimization of reaction contact time and concentration of TiO2 considering CAP and its by-products removal as well as effluent ecotoxicity elimination. Considering a CAP real concentration of 25mgL(-1), kinetic degradation curves were determined at 0.1, 0.2, 0.4, 0.8, 1.6 and 3.2gL(-1) TiO2 after 5, 10, 30, 60 and 120min reaction time. Treated samples were checked for the presence of by-products and residual toxicity (V. fischeri, P. subcapitata, L. sativum and D. magna). Results evidenced that the best combination for CAP and its by-products removal could be set at 1.6gL(-1) of TiO2 for 120min with an average residual toxicity of approximately 10%, that is the threshold set for negative controls in most toxicity tests for blank and general toxicity test acceptability.

Pollution by metal and metalloid ions is one of the most widespread environmental concerns. They are non-biodegradable, and, generally, present high water solubility facilitating their environmental mobilisation interacting with abiotic and biotic components such as adsorption onto natural colloids or even accumulation by living organisms, thus, threatening human health and ecosystems. Therefore, there is a high demand for effective removal treatments of heavy metals, making the application of adsorption materials such as polymer-functionalized nanocomposites (PFNCs), increasingly attractive. PFNCs retain the inherent remarkable surface properties of nanoparticles, while the polymeric support materials provide high stability and processability. These nanoparticle-matrix materials are of great interest for metals and metalloids removal thanks to the functional groups of the polymeric matrixes that provide specific bindings to target pollutants. This review discusses PFNCs synthesis, characterization and performance in adsorption processes as well as the potential environmental risks and perspectives.

Anthropogenic pressures can adversely affect the quality of coastal sediment posing at risk human health and the ecosystem. The Southeastern Tyrrhenian Sea (STS) coast (Italy) is still largely unexplored under this point of view. This study investigated for the first time in the area the seasonal variation and potential impact of selected metals (Cd, Cr, Cu, Ni, and Pb) and tributyltin (TBT) from sediment samples collected along the STS coast (Casalvelino Marina, Casalvelino Bay, Acciaroli Marina and Acciaroli Bay) in the perspective of Water Framework Directive and Marine Strategy Framework Directive. Data were compared to the contamination background levels of Punta Licosa reference site considering elemental enrichment factors (EFs) and single substance- and mixture-based risk characterisation ratios. Further, data were discussed considering the review of Southern Tyrrhenian Sea sediment quality. Results evidenced an increase of contamination levels from March to October showing that marinas are more impacted than bays. Sediment EFs highlighted that contamination levels were always greater than the reference site like risk characterisation ratios, suggesting the presence of potential threats. The sediment quality database generated after literature review revealed a similar situation for the whole Southern Tyrrhenian Sea.

Two solar driven Advanced Oxidation Processes (AOPs), namely sunlight/H2O2 and sunlight/peracetic acid (PAA), were investigated for the inactivation of two bacterial families (Escherichia coli and Enterococci) in real urban wastewater. Preliminary lab scale experiments were performed by using a solar simulator in order to evaluate the proper initial dose of H2O2 and PAA, respectively. According to the results achieved, 50 and 100âEUR...mgâEUR...Lâ^'1 of H2O2 and 4 and 8âEUR...mgâEUR...Lâ^'1 of PAA were chosen for the subsequent pilot scale experiments in a Compound Parabolic Collector (CPC) based reactor. The sunlight/PAA process resulted in a higher inactivation rate (3.52 log units of E. coli and 4.50 log units of Enterococci with an initial dose of 8âEUR...mg PAA Lâ^'1) compared to sunlight/H2O2 process (3.13 log units of E. coli and 2.45 log units of Enterococci with an initial dose of 100âEUR...mg H2O2 Lâ^'1) after 120âEUR...min of solar irradiation (7.42âEUR...kJâEUR...Lâ^'1 cumulative energy per unit of volume). It is noteworthy that significantly lower initial doses of PAA allowed to achieve a higher inactivation rate compared to H2O2, which makes sunlight/PAA an attractive option for wastewater disinfection in small communities.

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.

The use of compost for soil amendment is a promising agricultural practice environmentally and economically viable. In the framework of a wide research project designed to evaluate the effects of soil amendment with municipal solid waste compost in comparison with traditional mineral fertilization practices, 54 different cultivars (Cvs) of potatoes were AFLP (amplified fragment length polymorphism) molecularly fingerprinted. The seven most genetically biodiverse potato Cvs were used to establish an experimental field in southern Italy. The field area was divided into two portions fertilized with compost (20 Mg ha(-1)) or with ammonium sulphate (200 kg ha(-1)). No significant differences in productivity, organoleptic characteristics and element concentrations were observed between the potato tubers obtained with both kinds of soil fertilization, while the tubers grown on compost amended soil showed, on average, higher K concentrations with respect to those grown on mineral fertilised soil. cDNA-AFLP (complementary DNA-AFLP) and MSAP (methylation sensitive amplified polymorphism) analyses were carried out on both leaves and tubers of one selected Cv to estimate if any transcriptome alterations or epigenetic modifications were induced by the two kinds of fertilization, however no variations were detected. Chemical and biological soil qualities (i.e., microbial respiration, FDA hydrolysis, alkaline and acid phosphatase) were assessed on soil samples at the start of the experiment and at the end of potato crop cycle. No significant differences in soil pH and limited ones, in the available fraction of some trace elements, were observed; while conductivity was much higher for the compost amended portion of the experimental field. Microbial respiration, FDA hydrolysis and acid phosphatase activities were significantly increased by compost amendment, in comparison with mineral fertilization. Finally, a sensory panel of potato Cvs detected no significant differences among qualitative descriptors and among potatoes coming from the two differently fertilized soils.

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.

Perchlorate is regarded as an emerging persistent inorganic contaminant. It is widely known that perchlorate is an endocrine disruptor as it competitively inhibits iodide transport in the thyroid gland. As drinking water is the major source of human exposure to perchlorate, its occurrence in commercially available bottled waters purchased in different regions of Italy was investigated. Perchlorate was measured using the rapid, sensitive, and selective LC-ESI-MS/MS (liquid chromatography-electrospray tandem mass spectrometry) method by multiple reaction monitoring (MRM) of the transition 98.8→82.8, which corresponds to the loss of one oxygen atom in the perchlorate ion (ClO 4− →ClO 3− ). The chlorine isotope ratio ( 35 Cl/ 37 Cl) was used as a confirmation tool. The limit of quantification (LOQ) for this method was 5 ng/L, and the recovery ranged from 94% to 108%. Perchlorate was detected in 44 of the 62 drinking waters tested, with concentrations ranging from

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.

The case for highly selective long range “proton assisted” electron transfer in biomolecules (PA-ET), involving the hopping of protons and hydrogen atoms along H-bond chains connecting two redox sites, is discussed and analyzed on systems closely resembling typical biochemical sequences. These systems consist of an electron acceptor, an H-bond/covalent-bridge chain and an electron donor, and monohydroparabenzoquinone as the electron acceptor and a xanthine-like molecule as the electron donor and acceptor species held together by one or more peptide bridges. It is shown that, in biochemical structures, despite the involvement of the imidol (oximine) form of the peptide link, (a) PA-ET is energetically efficient and (b) the rate constants for proton-transfer, which is arguably the rate-controlling step, are reasonably high, the transfer times being on the order of hundreds of picoseconds.

The morphology of the delta and gamma forms of syndiotactic polystyrene (sPS) was investigated using scanning electron microscopy. The crystalline forms, delta and gamma, characterized by the chains in helical conformation, were obtained by solvent-induced crystallization from the amorphous glassy polymer. Dichloromethane and acetone were used to obtain the delta and the gamma form, respectively. The last form was obtained by thermal treatments of the delta form, too. The surface of the solvent-crystallized samples shows a texture characterized by oriented elements and cavities, whereas the internal part is microspherulitic in the case of the delta form and is more complex in the gamma form. At variance, the gamma form obtained by annealing the delta form shows a much more regular microspherulitic texture.

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.