Photoelectrocatalysis (PEC) was applied for the degradation of PFASs in natural groundwater collected from two wells located in the Veneto Region (Italy) where a massive contamination of the aquifer was discovered. Out of 48 monitored species, up to 9 PFASs were detected. On average, the degradation rate followed the order: PFOA>PFHpA>PFHxA approximate to PFPeA>PFBA and PFOS>PFHpS; the concentration of PFBS and PFHxS did not change during the tests. The overall PFASs concentration decreased by 63 % in well 1 and by 65 % in well 2. PEC tests of PFOA solutions ([PFOA] = 2 mu g/l; [K2SO4] = 4 mM] induced the transient formation of PFHpA, followed by PFHxA, PFPeA and PFBA, confirming the reaction pathway consisting of decarboxylation followed by a stepwise losing of CF2 units, transiently forming shorter chain intermediates. PEC efficiency was compared to photolysis. According to electrical energy per order of magnitude, PEC outperforms conventional photolysis and most of the other advanced oxidation processes reported in literature.

Treated wastewater (TWW) is increasingly recognized as a valuable resource for agriculture and water management in the Mediterranean region. However, its use can pose significant risks due to the potential presence of emerging contaminants of concern (ECCs), including personal care products, pesticides, food additives, and pharmaceuticals. This study aimed to evaluate the impact of irrigation with TWW on the accumulation of ECCs within the soil-plant system during a processing tomato (Solanum lycopersicum L.)-durum wheat (Triticum turgidum spp. durum) crop succession. The experiment was carried out on Petrocalcic Palexerolls soil. Over two experimental years, both crops were irrigated using two water sources: TWW and freshwater (FW) as a control. Of the 17 compounds detected in the TWW, only 8 were found in the soil (clarithromycin, carbamazepine, fluconazole, climbazole, flecainide, sitagliptin, telmisartan and venlafaxine). The use of TWW effluent led to a significant increase in the soil of carbamazepine up to 3.3 f 0.5 ng g- 1, sitagliptin up to 9.4 f 0.4 ng g- 1, flecainide up to 8.3 f 1.6 ng g- 1, and clarithromycin up to 5.3 f 0.6 ng g- 1, highlighting their potential accumulation during the two tomato-wheat cycles. Crop uptake varied depending on the specific ECC, with different levels detected in plant roots, leaves, and stems. Importantly, no ECCs were detected in the edible parts of either crop, with concentrations below the limit of quantification. These findings underscore the potential of using TWW for irrigation without compromising food safety in crops like tomatoes and durum wheat. However, continued monitoring and further research are essential to fully understand the long-term effects of ECCs on agricultural systems and ensure the protection of both human health and the environment.

IntroductionEmerging contaminants in irrigation wastewater can cause bioaccumulation in crops, posing health risks to humans and other living organisms. The extent to which different emerging contaminants (ECs) are taken up by plants varies depending on the physicochemical properties of the contaminants and the type of crops grown.MethodsThis study investigated the fate of emerging contaminants (ECs), particularly pharmaceuticals, in durum wheat grown on soils irrigated with treated wastewater in southern Italy. The experiment was conducted in lysimeters irrigated with wastewater during previous crop cycles, assessing the presence and distribution of ECs in both soil and plant tissues. Three different levels of exposure to ECs were compared: freshwater irrigation (FW), wastewater treated to European average contaminant levels (TWWx1), and a triple dose of contaminants (TWWx3).ResultsThe behavior of 12 different ECs in the plant-soil complex was analyzed and found variable. Fluconazole and carbamazepine were found to have higher uptake concentrations in the plant, with accumulation observed in the plant and grain, especially in the TWWx3 treatment. However, some ECs (such as Sulfamethoxazole, Trimethoprim, Ketoprofen, Diclofenac, Metoprolol, and Naproxen) showed high uncertainties in their fate, probably due to degradation in soil and influential crop parameters.DiscussionThe results of this study contribute to the argument that the reuse of treated wastewater for irrigation, if properly monitored, can be a safe approach in agriculture and can support policymakers in developing future legislative frameworks for sustainable water management.

IntroductionThe use of treated municipal wastewater (TWW) represents a relevant opportunity for irrigation of agricultural crops in semi-arid regions to counter the increasing water scarcity. Pharmaceutically active compounds (PhACs) are often detected in treated wastewater, posing a risk to humans and the environment. PhACs can accumulate in soils and translocate into different plant tissues, reaching, in some cases, edible organs and entering the food chain.MethodsThis study evaluated the uptake and translocation processes of 10 PhACs by olive trees irrigated with TWW, investigating their accumulation in different plant organs. The experiment was conducted in southern Italy, in 2-year-old plants irrigated with three different types of water: freshwater (FW), TWW spiked with 10 PhACs at a concentration of 200 µg L−1 (1× TWW), and at a triple dose (3× TWW), from July to October 2021. The concentration of PhACs in soil and plant organs was assessed, collecting samples of root, stem, shoot, leaf, fruit, and kernel at 0 (T0), 50 (T1), and 107 (T2) days of irrigation. PhACs extraction from soil and plant organs was carried out using the QuEChERS method, and their concentrations were determined by high-resolution mass spectrometry coupled with liquid chromatography.ResultsResults of uptake factors (UF) showed a different behavior between compounds according to their physicochemical properties, highlighting PhACs accumulation and translocation in different plant organs (also edible part) in 1× TWW and 3× TWW compared to FW. Two PhACs, carbamazepine and fluconazole, showed interactions with the soil–plant system, translocating also in the aerial part of the plant, with a translocation factor (TF) greater than 1, which indicates high root-to-leaf translocation.DiscussionFindings highlight that only few PhACs among the selected compounds can be uptaken by woody plants and accumulated in edible parts at low concentration. No effects of PhACs exposure on plant growth have been detected. Despite the attention to be paid to the few compounds that translocate into edible organs, these results are promising for adapting wastewater irrigation in crops. Increasing knowledge about PhACs behavior in woody plants can be important for developing optimized wastewater irrigation and soil management strategies to reduce PhACs accumulation and translocation in plants.

In the last decades particular attention is being paid to the efficient and effective removal of compounds of emergingconcern (CECs) present in wastewater before their eventual reuse or disposal. Several technologies have been devel-oped for the degradation of CECs in aqueous matrix, in this regard advanced oxidation processes (AOPs) represent anascent technological solution developed on a laboratory scale with applications on a prototype scale. The experimen-tal evidences have shown that AOPs processes can oxidize numerous organic compounds in a much faster and moreefficient way than that of the most common disinfection processes. The most common AOPs processes are thosethat involve the use of H2O2/UV, O3/UV, H2O2/O3,H2O2/O3/UV, Fenton and photo-Fenton. The aim of this work isto illustrate the results of a comparative LCA study of a laboratory scale UV-C photoreactor for the tertiary treatmentof urban wastewater of three treatment systems (UV-C, UV-C + H2O2e UV-C + TiO2). In particular, the specificobjective is to evaluate, fromanenvironmentalpoint ofview, aninnovative advanced oxidation system based on nano-structures TiO2immobilized on a stainless steel mesh. Compared to the UV-C photolysis reference system, the additionof hydrogen peroxide reduces the total environmental impact of the system by almost 75 %, while the use of thestainless-steel mesh coated by the nanostructures titanium dioxide reduces the UV-C environmental impact by 30 %. These results are due to the lower energy consumption of these last treatments compared to photolysis alone.The main impacts of the three systems are related to the electric power consumption of the centrifugal pump(63-64 %) and of the UV-C lamp (32-33 %). The LCA applied to these systems has shown that TiO2assistedphotocatalysis is not yet advantageous from an environmental point of view and that, therefore, the efficiency ofthe system needs to be improved

The reuse of treated wastewater for crop irrigation is vital in water-scarce semi-arid regions. However, concerns arise regarding emerging contaminants (ECs) that persist in treated wastewater and may accumulate in irrigated crops, potentially entering the food chain and the environment. This pilot-scale study conducted in southern Italy focused on tomato plants (Solanum lycopersicum L. cv Taylor F1) irrigated with treated wastewater to investigate EC uptake, accumulation, and translocation processes. The experiment spanned from June to September 2021 and involved three irrigation strategies: conventional water (FW), treated wastewater spiked with 10 target contaminants at the European average dose (TWWx1), and tertiary WWTP effluent spiked with the target contaminants at a triple dose (TWWx3). The results showed distinct behavior and distribution of ECs between the TWWx1 and TWWx3 strategies. In the TWWx3 strategy, clarithromycin, carbamazepine, metoprolol, fluconazole, and climbazole exhibited interactions with the soil-plant system, with varying degradation rates, soil accumulation rates, and plant accumulation rates. In contrast, naproxen, ketoprofen, diclofenac, sulfamethoxazole, and trimethoprim showed degradation. These findings imply that some ECs may be actively taken up by plants, potentially introducing them into the food chain and raising concerns for humans and the environment.

Two advanced oxidation processes (AOPs), namely ozone/H2O2 and UV/H2O2, were tested at pilot scale as zero-liquid-discharge alternative treatments for the removal of microbiological (bacteria and viruses), chemical (compounds of emerging concern (CECs)) and genotoxic responses from tertiary municipal wastewater for indirect potable reuse (IPR). The AOP treated effluents were further subjected to granular activated carbon (GAC) adsorption and UV disinfection, following the concept of multiple treatment barriers. As a reference, a consolidated advanced wastewater treatment train consisting of ultrafiltration, UV disinfection, and reverse osmosis (RO) was also employed. The results showed that, for the same electrical energy applied, the ozone/H2O2 treatment was more effective than the UV/H2O2 treatment in removing CECs. Specifically, the ozone/H2O2 treatment, intensified by high pressure and high mixing, achieved an average CECs removal efficiency higher than UV/H2O2 (66.8% with respect to 18.4%). The subsequent GAC adsorption step, applied downstream the AOPs, further improved the removal efficiency of the whole treatment trains, achieving rates of 98.5% and 96.8% for the ozone/H2O2 and UV/H2O2 treatments, respectively. In contrast, the ultrafiltration step of the reference treatment train only achieved a removal percentage of 22.5%, which increased to 99% when reverse osmosis was used as the final step. Microbiological investigations showed that all three wastewater treatment lines displayed good performance in the complete removal of regulated and optional parameters according to both national and the European Directive 2020/2184. Only P. aeruginosa resulted resistant to all treatments with a higher removal by UV/H2O2 when higher UV dose was applied. In addition, E. coli STEC/VTEC and enteric viruses, were found to be completely removed in all tested treatments and no genotoxic activity was detected even after a 1000-fold concentration. The obtained results suggest that the investigated treatments are suitable for groundwater recharge to be used as a potable water source being such a procedure an IPR. The intensified ozone/H2O2 or UV/H2O2 treatments can be conveniently incorporated into a multi-barrier zero-liquid-discharge scheme, thus avoiding the management issues associated with the retentate of the conventional scheme that uses reverse osmosis. By including the chemical cost associated with using 11-12 mg/L of H2O2 in the cost calculations, the overall operational cost (energy plus chemical) required to achieve 50% average CECs removal in tertiary effluent for an hypothetical full-scale plant of 250 m3/h (or 25,000 inhabitants) was 0.183 €/m3 and 0.425 €/m3 for ozone/H2O2 and UV/H2O2 treatment train, respectively.

In the present study natural deep eutectic solvents (NADES) were investigated as green and sustainable approach for the extraction of Polyfluoroalkyl Substances (PFAS) from aqueous solutions. NADES, derived from natural products, offer environmentally friendly, low-cost, and biodegradable properties. A hydrophobic NADES, menthol-acetic acid, was shown to be able to extract perfluoroheptanoic acid (PFHpA) from water. The extraction efficiency was about 90 % and was not affected by the PFHpA concentration (0.23-350 mg/L) and by the initial pH of the aqueous solution at the tested conditions. After extraction the pH of the aqueous solution dropped to 2.2, due to a partial dissolution of the acetic acid from the NADES. The mechanism of interaction between the PFHpA and the NADES was unraveled using Density Functional Theory (DFT) calculations. These findings highlight the potential of NADES as a green and sustainable solution for PFAS remediation.

The irrigation with treated wastewater is among the main anthropogenic sources for the release of pharmaceuticals (PhACs) into the soils and their translocation into crops, with possible toxic and adverse effects on humans. The arbuscular mycorrhizal fungi (AMF) can be employed for the reduction of organic soil pollutants, even if their efficiency depends on the mycorrhizal fungi, the plant colonized, and the type and concentration of the contaminant. This study aimed to evaluate the uptake of PhACs from wastewaters of different qualities used for the irrigation of mycorrhizal artichoke plants, the presence in their edible parts and the role of the arbuscular mycorrhizal fungi. The research was carried out on artichoke plants not inoculated and inoculated with two different AMF and irrigated with treated wastewater (TW), groundwater (GW) or GW spiked with different and selected PhACs (SGW). The inocula were a crude inoculum of Septoglomus viscosum (MSE) and a commercial inoculum of Glomus intraradices and Glomus mosseae (MSY). The results of the present study showed that carbamazepine and fluconazole were found in the artichoke only with SGW irrigation. The mycorrhizal plants showed a reduction of the pharmaceutical's uptake, and within the AMF, MSE was more effective in preventing their absorption and translocation.

This study explored process synergies attainable by integrating a vacuum ultraviolet-based advanced oxidation process with biofiltration. A comparison using granular activated carbon or granular zeolite as filtration media were examined in context of advanced wastewater treatment for potable reuse. Six biofiltration columns, three with granular activated carbon and three with granular zeolite, were operated in parallel and batch-fed daily with nitrified secondary effluent. After achieving a pseudo-steady state through the filter columns, vacuum ultraviolet treatment was applied as pre-treatment or as post-treatment, at two different applied energies (i.e., VUV-E1=1 kWh/m(3) and VUV-E10=10 kWh/m(3)). Once granular activated carbon had transitioned to biologically activated carbon, as determined based on soluble chemical oxygen demand removal, adsorption was still observed as the main mechanism for contaminants of emerging concern and nitrate removal. Vacuum ultraviolet pre-treatment markedly improved contaminants of emerging concern removal through the integrated system, achieving 40% at VUV-E1 and 90% at VUV-E10. When applied as post-treatment to zeolite column effluents, VUV-E1 and VUV-E10 further increased contaminants of emerging concern removal by 20% and 90%, respectively. In the zeolite system, vacuum ultraviolet pre-treatment also increased soluble chemical oxygen demand removal efficiency, indicating that higher energy vacuum ultraviolet increased biodegradability. Total prokaryotes were two-fold more abundant in biologically activated carbon than in zeolite, with vacuum ultraviolet pretreatment markedly affecting microbial diversity, both in terms of richness and composition. Media type only marginally affected microbial richness in the biofilters but showed a marked impact on structural composition. No clear relationship between compositional structure and depth was observed.

The photocatalytic efficiency of an innovative UV-light catalyst consisting of a mesoporous TiO2 coating on glass fibers was investigated for the degradation of pharmaceuticals (PhACs) in wastewater effluents. Photocatalytic activity of the synthesized material was tested, for the first time, on a secondary wastewater effluent spiked with nine PhACs and the results were compared with the photolysis used as a benchmark treatment. Replicate experiments were performed in a flow reactor equipped with a UV radiation source emitting at 254 nm. Interestingly, the novel photocatalyst led to the increase of the degradation of carbamazepine and trimethoprim (about 2.2 times faster than the photolysis). Several transformation products (TPs) resulting from both the spiked PhACs and the compounds naturally occurring in the secondary wastewater effluent were identified through UPLC-QTOF/MS/MS. Some of them, produced mainly from carbamazepine and trimethoprim, were still present at the end of the photolytic treatment, while they were completely or partially removed by the photocatalytic treatment.

This study evaluated whether some chemical and microbial contaminants in treated sewage effluents from two wastewater treatment plants (WWTP) reached the groundwater when they drained through a fractured karst vadose zone (WWTP-K) and a porous vadose zone (WWTP-P). Forty-five samples of sewage water (SW), treated water (TW), and monitoring well (MW), collected from WWTP-P (24) and WWTP-K (21), were analyzed for a range of microbiological and chemical properties. The E. coli and Salmonella counts were below the limits outlined in the Legislative Decree 152/06 in effluents from both types of WWTP. Enteric viruses were found in 37.5% and 12.5% of the SW and TW from WWTP-P, respectively. The percentages of Pepper mild mottle virus isolated were higher in TW (62.5% in WWTP-P, 85.7% in WWTP-K) than in SW and MW. The residual concentrations of contaminants of emerging concern (CEC) of each drug category were higher in the MW downstream of WWTP-K than of WWTP-P. Our results showed that the porous vadose zone was more effective at reducing the contaminant loads than the fractured karst one, especially the CEC, in the effluent. The legislation should include other parameters to minimize the risks from treated effluent that is discharged to soil.

The quality of water bodies is continuously threatened by the growing human activities and the consequent release of different classes of contaminants, known to be recalcitrant to elimination in conventional wastewater treatment plants. These pollutants named contaminants of emerging concern (CECs) may have a strong impact not only on the environment but also on human health due to long-term exposure. Currently, most of the research activities in the field of wastewater treatment are oriented toward the development of innovative technologies with enhanced performance in terms of efficiency and applicability in full scale for the removal of CECs. This review focuses on the recent progress in syntheses and applications of novel TiO2 nanocomposite photocatalysts for the effective degradation of pharmaceuticals (PhACs) in water matrices, known to be a wide class of CECs. The development of ultraviolet response and visible-light response of immobilized TiO2 on different supports were reviewed and the application of photocatalysis, also combined with electrochemical processes (photoelectrocatalysis, PEC) in the removal of PhACs were summarized.

This study investigated the environmental contamination of groundwater as a consequence of the discharge of treated wastewater into the soil. The investigation focused on a wastewater treatment plant located in an area fractured by karst in the Salento peninsula (Apulia, Italy). Water samples were collected at four sites (raw wastewater, treated wastewater, infiltration trench, and monitoring well), monthly from May to December 2019 (with the exception of August), and were tested for 1) panel of bacteria; 2) enteric viruses; and 3) chemical substances. A gradual reduction in the concentration of bacteria, viruses and contaminants of emerging concern was observed across the profile of soil fissured by karst. All monitored bacteria were absent from the monitoring well, except for Pseudomonas aeruginosa. Pepper mild mottle virus and adenovirus were detected at all sampling sites. Personal care products and X-ray contrast media showed the greatest decrease in concentration from infiltration trench to the monitoring well, while the highest residual concentrations in the monitoring well were found for anticonvulsants (78.5%), antimicrobials (41.3%), and antipsychotic drugs (38.6%). Our results show that parameters provided by current law may not always be sufficient to evaluate the sanitary risk relating to the discharge of treated wastewater to the soil.