Pharmaceuticals in edible crops irrigated with reclaimed wastewater: Evidence from a large survey in Israel

Environmental Stress-Induced Alterations in Embryo Developmental Morphokinetics

The association between embryo morphokinetics and its developmental competence is well documented. For instance, early cleaved embryos are more competent in developing to blastocysts, whereas the proportion of abnormally cleaved embryos that further developed to blastocysts is low. Numerous factors, such as the parental age, lifestyle, health, and smoking habits have been reported to affect the embryo morphokinetics and, consequently, its development. However, less is known about the effect of environmental stressors on embryo morphokinetics. The current review discusses the effect of the most concerning environmental stressors on embryo morphokinetics. These stresses include heat stress and human-made chemicals such as phthalates (e.g., bis-(2-ethylhexyl phthalate, dibutyl phthalate, dimethyl phthalate, and their primary metabolites), herbicides (e.g., diaminochlorotriazine, the primary metabolite of atrazine), pharmaceutical compounds (e.g., carbamazepine, nocodazole) and pro-oxidant agents (cumene hydroperoxide, Triton X-100), as well as naturally occurring toxins such as mycotoxin (e.g., aflatoxin B1 and its metabolite, and ochratoxin A). In addition, this review discusses the effect of ionizing or non-ionizing radiation and viral infections (e.g., SARS-CoV-2, papillomavirus). Finally, it points out some potential mechanisms that underlie the impairment of embryo morphokinetics, and it suggests protective compounds, mainly the supplementation of antioxidants to improve the morphokinetics, and consequently, the embryo developmental competence.

Towards sustainable water reuse: A critical review and meta-analysis of emerging chemical contaminants with risk-based evaluation, health hazard prediction and prioritization for assessment of effluent water quality

Reuse of treated wastewater is necessary to address water shortages in a changing climate. Sustainability of wastewater reuse requires reducing the environmental impacts of contaminants of emerging concern (CECs), but it is being questioned as CECs are not regulated in the assessment of effluent water quality for reuse both nationally in Sweden and at the broader European Union level. There is also a lack of details in this topic on which CECs to be addressed and methodologies to be used for assessing their environmental impacts. A better understanding of the ecological risks and health hazards of CECs associated with wastewater reuse will assist in the development of effective regulations on water reuse, (inter)nationally, as well as related treatment/monitoring guidelines. This review provides a list of specific chemical CECs that hinder sustainable wastewater reuse, and also demonstrates a holistic quantitative methodology for assessing, scoring and prioritizing their associated ecological risks and health hazards posed to the environment and humans. To achieve this, we compile information and concentrations of a wide range of CECs (∼15 000 data entries) identified in Swedish effluent wastewater from domestic (blackwater, greywater, mixture of both) and municipal settings, and further perform a meta-analysis of their potentials for 14 risk and hazard features, consisting of ecological risk, environmental hazard, and human health hazard. The features are then scored against defined criteria including guideline values, followed by score ranking for prioritization. This finally produces a unique list of chemical CECs from high to low priority based on risk- and hazard-evaluations. Out of the priority chemicals, 30, mainly pharmaceuticals, had risk quotient ≥ 1, indicating ecological risk, 16 had environmental hazard being persistent and mobile, and around 60 resulted in positive predictions for at least four human health hazards (particularly skin sensitization, developmental toxicity, hepatoxicity, and carcinogenicity). The 10 highest-priority chemicals (final score 2.3-3.0 out of 4.0) were venlafaxine, bicalutamide, desvenlafaxine, diclofenac, amoxicillin, clarithromycin, diethyltoluamide, genistein, azithromycin, and fexofenadine. Potential crop exposure to selected chemicals following one year of wastewater reuse for agricultural irrigation was also estimated, resulting in a range of 0.04 ng/kg (fluoxetine) to 1160 ng/kg (carbamazepine). Overall, our work will help focus efforts and costs on the critical chemicals in future (waste)water-related studies, such as, to evaluate removal efficiency of advanced treatment technologies and to study upstream source tracing (polluter-pays principle), and also in supporting policymakers to better regulate CECs for sustainable wastewater reuse in the future.

Are pharmaceutical residues in crops a threat to human health?

The application of biosolids, manure, and slurry onto agricultural soils and the growing use of treated wastewater in agriculture result in the introduction of human and veterinary pharmaceuticals to the environment. Once in the soil environment, pharmaceuticals may be taken up by crops, resulting in consequent human exposure to pharmaceutical residues. The potential side effects of pharmaceuticals administered in human medicine are widely documented; however, far less is known regarding the risks that arise from incidental dietary exposure. The aim of this study was to evaluate human exposure to pharmaceutical residues in crops and assess the associated risk to health for a range of pharmaceuticals frequently detected in soils. Estimated concentrations of carbamazepine, oxytetracycline, sulfamethoxazole, trimethoprim, and tetracycline in soil were used in conjunction with plant uptake and crop consumption data to estimate daily exposures to each compound. Exposure concentrations were compared to Acceptable Daily Intakes (ADIs) to determine the level of risk. Generally, exposure concentrations were lower than ADIs. The exceptions were carbamazepine, and trimethoprim and sulfamethoxazole under conservative, worst-case scenarios, where a potential risk to human health was predicted. Future research therefore needs to prioritize investigation into the health effects following exposure to these compounds from consumption of contaminated crops.

Molasses-based waste water irrigation: a friend or foe for carrot (Daucus carota L.) growth, yield and nutritional quality

Management of molasses-based wastewater generated in yeast and sugar industries is a major environmental concern due to its high chemical oxygen demand and other recalcitrant substances. Several strategies have been used to reduce the inland discharge of wastewater but the results are not satisfactory due to high operating cost. However, reuse of molasses-based wastewater irrigation in agriculture has been a major interest nowadays to reduce the freshwater consumption. Thus, it is crucial to monitor the impacts of molasses-based waste water irrigation on growth, metabolism, yield and nutritional quality of crops for safer consumer's health. In present study, carrot seeds of a local cultivar (T-29) were germinated on filter paper in Petri dishes under controlled conditions. The germinated seeds were then transplanted into pots and irrigated with three different treatments normal water (T0), diluted molasses-based wastewater (T1), and untreated molasses-based wastewater (T2), in six replicates. Results revealed that carrot irrigated with untreated molasses-based waste water had exhibited significant reductions in growth, yield, physiology, metabolism, and nutritional contents. Additionally, accumulation of Cd and Pb contents in carrot roots irrigated with untreated molasses-based waste water exceed the permissible limits suggested by WHO and their consumption may cause health risks. While, diluted molasses-based waste water irrigation positively enhanced the growth, yield of carrot plants without affecting the nutritional quality. This strategy is cost effective, appeared as most appropriate alternative mean to reduce the freshwater consumption in water deficit regions of the world.

Comprehensive Assessment of Herbicide Toxicity on Navicula sp. Algae: Effects on Growth, Chlorophyll Content, Antioxidant System, and Lipid Metabolism

This study investigated the effects of herbicide exposure on Navicula sp. (MASCC-0035) algae, focusing on growth density, chlorophyll content, antioxidant system, and lipid metabolism. Navicula cultures were exposed to different concentrations of atrazine (ATZ), glyphosate (Gly), and acetochlor (ACT) for 96 h. Results showed a significant decrease in cell numbers, with higher herbicide concentrations having the most noticeable impacts. For instance, Gly-G2 had reduced cell populations by 21.00% at 96 h. Chlorophyll content varied, with Gly having a greater impact on chlorophyll a compared to ATZ and ACT. Herbicide exposure also affected the antioxidant system, altering levels of soluble sugar, soluble protein, and reactive oxygen species (ROS). Higher herbicide rates increased soluble sugar content (e.g., ATZ, Gly, and ACT-G2 had increased by 14.03%, 19.88%, and 19.83%, respectively, at 72 h) but decreased soluble protein content, notably in Gly-G2 by 11.40%, indicating cellular stress. Lipid metabolism analysis revealed complex responses, with changes in free proline, fatty acids, and lipase content, each herbicide exerting distinct effects. These findings highlight the multifaceted impacts of herbicide exposure on Navicula algae, emphasizing the need for further research to understand ecological implications and develop mitigation strategies for aquatic ecosystems.

Divergent effects of azithromycin on purple corn (Zea mays L.) cultivation: Impact on biomass and antioxidant compounds

The present study assessed the impact of using irrigation water contaminated with Azithromycin (AZM) residues on the biomass and antioxidant compounds of purple corn; for this purpose, the plants were cultivated under ambient conditions, and the substrate used consisted of soil free from AZM residues, mixed with compost in a ratio of 1:1 (v/v). The experiment was completely randomized with four replications, with treatments of 0, 1, 10, and 100 μg/L of AZM. The results indicate that the presence of AZM in irrigation water at doses of 1 and 10 μg/L increases the weight of dry aboveground biomass, while at an amount of 100 μg/L, it decreases. Likewise, this study reveals that by increasing the concentration of AZM from 1 to 10 μg/L, total polyphenols and monomeric anthocyanins double, in contrast, with an increase to 100 μg/L, these decrease by 44 and 53%, respectively. It has been demonstrated that purple corn exposed to the antibiotic AZM at low doses has a notable antioxidant function in terms of DPPH and ORAC. The content of flavonols, phenolic acids, and flavanols increases by 57, 28, and 83%, respectively, when the AZM concentration is from 1 to 10 μg/L. However, with an increase to 100 μg/L, these compounds decrease by 17, 40, and 42%, respectively. On the other hand, stem length, root length, and dry weight of root biomass are not significantly affected by the presence of AZM in irrigation water.

A novel approach to identify critical knowledge gaps for food safety in circular food systems

The transition from linear production towards a circular agro-food system is an important step towards increasing Europe's sustainability. This requires re-designing the food production systems, which inevitably comes with challenges as regards controlling the safety of our food, animals and the ecosystem. Where in current food production systems many food safety hazards are understood and well-managed, it is anticipated that with the transition towards circular food production systems, known hazards may re-emerge and new hazards will appear or accumulate, leading to new -and less understood- food safety risks. In this perspective paper, we present a simple, yet effective approach, to identify knowledge gaps with regard to food safety in the transition to a circular food system. An approach with five questions is proposed, derived from current food safety management approaches like HACCP. Applying this to two cases shows that risk assessment and management should emphasize more on the exposure to unexpected (with regards to its nature and its origin) hazards, as hazards might circulate and accumulate in the food production system. Five knowledge gaps became apparent: there's a need for (1) risk assessment and management to focus more on unknown hazards and mixtures of hazards, (2) more data on the occurrence of hazards in by-products, (3) better understanding the fate of hazards in the circular food production system, (4) the development of models to adequately perform risk assessments for a broad range of hazards and (5) new ways of valorization of co-products in which a safe-by-design approach should be adopted.

Negligible adsorption and toxicity of microplastic fibers in disinfected secondary effluents

Wastewater treatment plants play a crucial role in controlling the transport of pollutants to the environment and often discharge persistent contaminants such as synthetic microplastic fibers (MFs) to the ecosystem. In this study, we examined the fate and toxicity of polyethylene terephthalate (PET) MFs fabricated from commercial cloth in post-disinfection secondary effluents by employing conditions that closely mimic disinfection processes applied in wastewater treatment plants. Challenging conventional assumptions, this study illustrated that oxidative treatment by chlorination and ozonation incurred no significant modification to the surface morphology of the MFs. Additionally, experimental results demonstrated that both pristine and oxidized MFs have minimal adsorption potential towards contaminants of emerging concern in both effluents and alkaline water. The limited adsorption was attributed to the inert nature of MFs and low surface area to volume ratio. Slight adsorption was observed for sotalol, sulfamethoxazole, and thiabendazole in alkaline water, where the governing adsorption interactions were suggested to be hydrogen bonding and electrostatic forces. Acute exposure experiments on human cells revealed no immediate toxicity; however, the chronic and long-term consequences of the exposure should be further investigated. Overall, despite the concern associated with MFs pollution, this work demonstrates the overall indifference of MFs in WWTP (i.e., minor effects of disinfection on MFs surface properties and limited adsorption potential toward a mix of trace organic pollutants), which does not change their acute toxicity toward living forms.

Alternating water sources to minimize contaminant accumulation in food plants from treated wastewater irrigation

The use of treated wastewater (TWW) for agricultural irrigation is a critical measure in advancing sustainable water management and agricultural production. However, TWW irrigation in agriculture serves as a conduit to introduce many contaminants of emerging concern (CECs) into the soil-plant-food continuum, posing potential environmental and human health risks. Currently, there are few practical options to mitigate the potential risk while promoting the safe reuse of TWW. In this greenhouse study, the accumulation of 11 commonly occurring CECs was evaluated in three vegetables (radish, lettuce, and tomato) subjected to two different irrigation schemes: whole-season irrigation with CEC-spiked water (FULL), and half-season irrigation with CEC-spiked water, followed by irrigation with clean water for the remaining season (HALF). Significant decreases (57.0-99.8 %, p < 0.05) in the accumulation of meprobamate, carbamazepine, PFBS, PFBA, and PFHxA in edible tissues were found for the HALF treatment with the alternating irrigation scheme. The CEC accumulation reduction was attributed to reduced chemical input, soil degradation, plant metabolism, and plant growth dilution. The structural equation modeling showed that this mitigation strategy was particularly effective for CECs with a high bioaccumulation potential and short half-life in soil, while less effective for those that are more persistent. The study findings demonstrate the effectiveness of this simple and on-farm applicable management strategy that can be used to minimize the potential contamination of food crops from the use of TWW and other marginal water sources in agriculture, while promoting safe reuse and contributing to environmental sustainability.

Uptake and translocation of pharmaceutically active compounds by olive tree (Olea europaea L.) irrigated with treated municipal wastewater

Introduction

The 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.

Methods

This 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.

Results

Results 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.

Discussion

Findings 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.

Degradation of carbamazepine in ice with bromate and nitrite: Role of reactive nitrogen species

Seasonal freezing of waters occurs during winter in cold regions. Bromate ( [Formula: see text] ) is a disinfection by-product generated during water treatment, its interaction with emerging contaminants may be affected by freezing. Nitrite ( [Formula: see text] ) is widely distributed in the environment, whereas its effect on the interaction of emerging contaminants and [Formula: see text] in ice may have been overlooked. Herein carbamazepine (CBZ) was selected as a model emerging contaminant to elucidate the role of reactive nitrogen species (RNS) in contaminant transformation during the reduction of [Formula: see text] by [Formula: see text] in ice. Results indicated that freezing significantly enhanced CBZ degradation by [Formula: see text] . The CBZ degradation by [Formula: see text] and [Formula: see text] in ice was 25.4 %-27.8 % higher than that by [Formula: see text] . Contributions of hydroxyl radical (•OH), bromine radical (•Br), and RNS to CBZ degradation in freezing/dark or sunlight systems were 8.1 % or 15.9 %, 25.4 % or 7.2 %, and 66.5 % or 76.9 %, respectively. Most CBZ was degraded by RNS generated during the reduction of [Formula: see text] by [Formula: see text] in ice, resulting in 16.4 % of transformation products being nitro-containing byproducts. Hybrid toxicity of CBZ/ [Formula: see text] / [Formula: see text] system was reduced effectively after the freezing-sunlight process. This study can provide new insights into the environmental fate of emerging contaminants, [Formula: see text] , and [Formula: see text] in cold regions.

Selection of pharmaceuticals of concern in reclaimed water for crop irrigation in the Mediterranean area

The reuse of reclaimed water in agriculture is being fostered in areas suffering from water scarcity. However, water pollutants can compromise food safety and pose a risk for the environment. This study aims to select the pharmaceutical compounds worth monitoring and investigating when reclaimed water is used for tomato and lettuce irrigation. A comprehensive study was first conducted to identify the pharmaceuticals frequently detected in secondary wastewater effluents in Catalonia (Northeast Spain). Priority pharmaceuticals were further selected based on their occurrence in secondary effluents, persistence (removal in conventional treatment), bioaccumulation potential, toxicity for aquatic organisms, and the risks they pose to the terrestrial environment and human health (through the consumption of crops). Out of the 47 preselected priority compounds, six could pose a risk to organisms living in soil irrigated with reclaimed water and seven could be potentially taken up by the crops. Nonetheless, no risk for human consumption was foreseen.

Evaluation of chemical contamination of crops produced in greenhouse by irrigation with reclaimed water

Using reclaimed water for agricultural irrigation is increasing worldwide to compensate for water scarcity. The aim of this work was to evaluate the uptake of some of the most commonly detected organic contaminants of emerging concern (CECs) and pesticides in regenerated water in a field study. Furthermore, it was studied their distribution and accumulation in the different parts of a crop (soil, plant and fruit). Three crops (cucumber, pepper and melon) were grown under controlled agronomic conditions in a greenhouse. In order to make an accurate evaluation of the process, "regenerated blank water" was spiked with 70 chemicals (including antibiotics, anti-inflammatories, analgesics, anaesthetics, anxiolytics, anticonvulsants, pesticides) at environmental concentrations (∼1 μg/L) and used for continuous crop irrigation. After crop season, the average total concentration of contaminants detected in the soil samples ranged from 132 to 232 μg/kg d.w depending of the crops type. Between 7 and 10 different contaminants were found in the harvested fruits, up to levels of 27.8 μg/kg f.w. cucumber, 12.4 μg/kg f.w. melon and 7.8 μg/kg f.w pepper. In general, cucumber fruit showed higher accumulation levels of contaminants than pepper and melon for most target analytes. The accumulation rates followed the order: root (0.2 %) < stem/leaf (1-4 %) < fruit (1-6 %) < soil (17-30 %). The experimental data obtained in this study were also used to assess the risk associated with the reuse of reclaimed water for crop irrigation as well to identify those contaminants that, due to their physicochemical properties, show higher accumulation rates and environmental impact.

Contamination of water, soil, and plants by micropollutants from reclaimed wastewater and sludge from a wastewater treatment plant

Several studies have shown that plants can absorb various micropollutants. The behavior of micropollutants from wastewater treatment plant resources was comprehensively investigated in raised beds in which either a mixture of vegetables or maize was grown. The beds were either irrigated with treated wastewater or enriched with sewage sludge or composted sewage sludge. Over the year, samples of wastewater, water drained from the beds, soils and plants were analyzed. Of the seventy-five analyzed substances, fifty-four, thirty-three and twenty-seven were quantified in wastewater, sewage sludge, and composted sludge, respectively. Alarmingly, approximately 20 % of the compounds from wastewater were also detected in the solutions leached from the beds irrigated with wastewater (e.g., gabapentin, tramadol, sertraline, carbamazepine, its metabolites, and benzotriazoles). In addition, a gradual increase in the content of four substances (telmisartan, venlafaxine, carbamazepine, citalopram) was recorded in these beds. The compounds from both biosolids used for soil enrichment tended to remain in the soils (e.g., telmisartan, venlafaxine, sertraline, its metabolite, citalopram, and its metabolite). Only four compounds (sertraline and three benzotriazoles) leached from these beds. Uptake of some chemicals (e.g., gabapentin, tramadol, carbamazepine and its metabolite, and venlafaxine and its metabolite) and their accumulation in plant tissues was observed mainly in vegetables grown on beds irrigated with wastewater. However, daily consumption values for edible plant parts and individual compounds did not indicate a direct threat to human health. Results of this innovative study show possible risks associated with the use of these resources in agriculture. Of particular concern is the possible micropollutants percolation towards groundwater, including those for which high sorption and thus low mobility in the soil environment is expected, such as sertraline. Soil and crop contamination cannot be neglected either.

Pharmacokinetics of the Recalcitrant Drug Lamotrigine: Identification and Distribution of Metabolites in Cucumber Plants

Treated wastewater is an important source of water for irrigation. As a result, irrigated crops are chronically exposed to wastewater-derived pharmaceuticals, such as the anticonvulsant drug lamotrigine. Lamotrigine is known to be taken up by plants, but its plant-derived metabolites and their distribution in different plant organs are unknown. This study aimed to detect and identify metabolites of lamotrigine in cucumber plants grown for 35 days in a hydroponic solution by using LC-MS/MS (Orbitrap) analysis. Our data showed that 96% of the lamotrigine taken up was metabolized. Sixteen metabolites possessing a lamotrigine core structure were detected. Reference standards confirmed two; five were tentatively identified, and nine molecular formulas were assigned. The data suggest that lamotrigine is metabolized via N-carbamylation, N-glucosidation, N-alkylation, N-formylation, N-oxidation, and amidine hydrolysis. The metabolites LTG-N2-oxide, M284, M312, and M370 were most likely produced in the roots and were translocated to the leaves. Metabolites M272, M312, M314, M354, M368, M370, and M418 were dominant in leaves. Only a few metabolites were detected in the fruits. With an increasing exposure time, lamotrigine leaf concentrations decreased because of continuous metabolism. Our data showed that the metabolism of lamotrigine in a plant is fast and that a majority of metabolites are concentrated in the roots and leaves.

The role of biochar and green compost amendments in the adsorption, leaching, and degradation of sulfamethoxazole in basic soil

The fate of the antibiotic sulfamethoxazole in amended soils remains unclear, moreover in basic soils. This work aimed to assess the adsorption, leaching, and biodegradation of sulfamethoxazole in unamended and biochar from holm oak pruning (BC)- and green compost from urban pruning (CG)-amended basic soil. Adsorption properties of the organic amendments and soil were determined by adsorption isotherms of sulfamethoxazole. The leachability of this antibiotic from unamended (Soil) and BC- (Soil + BC) and GC- (Soil + GC) amended soil was determined by leaching columns using water as solvent up to 250 mL. Finally, Soil, Soil + BC, and Soil + GC were spiked with sulfamethoxazole and incubated for 42 days. The degradation rate and microbial activity were periodically monitored. Adsorption isotherms showed poor adsorption of sulfamethoxazole in unamended basic soil. BC and CG showed good adsorption capacity. Soil + BC and Soil + GC increased the sulfamethoxazole adsorption capacity of the soil. The low sulfamethoxazole adsorption of Soil produced quick and intense sulfamethoxazole leaching. Soil + BC reduced the sulfamethoxazole leaching, unlike to Soil + GC which enhanced it concerning Soil. The pH of adsorption isotherms and leachates indicate that the anion of sulfamethoxazole was the major specie in unamended and amended soil. CG enhanced the microbial activity of the soil and promoted the degradability of sulfamethoxazole. In contrast, the high adsorption and low biostimulation effect of BC in soil reduced the degradation of sulfamethoxazole. The half-life of sulfamethoxazole was 2.6, 6.9, and 11.9 days for Soil + GC, Soil, and Soil + BC, respectively. This work shows the benefits and risks of two organic amendments, BC and GC, for the environmental fate of sulfamethoxazole. The different nature of the organic carbon of the amendments was responsible for the different effects on the soil.

Quantitative and qualitative approaches for CEC prioritization when reusing reclaimed water for irrigation needs - A critical review

The use of reclaimed water for irrigation is an option that is becoming increasingly widespread to alleviate water scarcity and to cope with drought. However, reclaimed water, if used for irrigation, may introduce Contaminants of Emerging Concern (CECs) into the agroecosystems, which may be taken up by the crops and subsequently enter the food chain. The number of CECs is steadily increasing due to their continuous introduction on the market for different uses. There is an urgent need to draw up a short list of potential high priority CECs, which are substances that could be taken up by plants and accumulated in food produce, and/or that could have negative effects on human health and the environment. This review presents and discusses the approaches developed to prioritize CECs when reclaimed water is (re-)used for irrigation. They are divided into quantitative methodologies, which estimate the risk for environmental compartments (soil and water), predators and humans through equations, and qualitative methodologies, which are instead conceptual frameworks or procedures based on the simultaneous combination of data/information/practices with the judgment of experts. Three antibiotics (erythromycin, sulfamethoxazole and ciprofloxacin), one estrogen (17-α ethinylestradiol) and one analgesic (ibuprofen) were found on at least two priority lists, although comparison among studies is still difficult. The review remarks that it is advisable to harmonize the different methodologies in order to identify the priority CECs to include in monitoring programs in reclaimed water reuse projects and to ensure a high level of protection for humans and the environment.

Factors driving PPCPs uptake by crops after wastewater irrigation and human health implications

Currently, water scarcity affects more than three billion people. Nevertheless, the volume of treated wastewater discharged into the environment is estimated to exceed 100 m3 per inhabitant/year. These water resources are regularly used in agriculture worldwide to overcome water shortages. Such a practice, however, entails the uptake of waterborne pollutants, such as pharmaceuticals and personal care products (PPCPs), by crops and their further access to the food web, constituting an additional route of human exposure to PPCPs, with potential health outcomes. In this study, the occurrence of 56 PPCPs in tomatoes, lettuce, and carrot, together with soil and irrigation water, was evaluated using a QuEChERS-based methodology for extraction and LC-MS/MS for analysis. The influence of the selected cultivation conditions on the plant uptake levels of PPCPs was assessed. Two irrigation water qualities (secondary and tertiary treatment effluents), two soil compositions (sandy and clayey), two irrigation systems (dripping and sprinkling), and three crop types (lettuce, tomato, and carrot) were tested. Carrots showed the highest load of PPCPs (7787 ng/g dw), followed by tomatoes (1692 ng/g dw) and lettuces (1248 ng/g dw). The most translocated PPCPs were norfluoxetine (fluoxetine antidepressant main metabolite) (521 ng/g dw), and the anti-inflammatory diclofenac (360 ng/g dw). Nine PPCPs, are reported to be accumulated in crops for the first time. Water quality was the most important factor for reducing PPCPs' plant uptake. Overall, the best conditions for reducing PPCP uptake by crops were irrigation with reclaimed water by sprinkling in soils with higher clay content. The risk assessment performed revealed that the crops' consumption posed no risk to human health. This study serves as the first comprehensive assessment of the relevance of diverse cultivation factors on PPCPs' plant uptake under field agricultural practices.

Clarithromycin as soil and environmental pollutant: Adsorption-desorption processes and influence of pH

Antibiotics pollution is a growing environmental issue, as high amounts of these compounds are found in soil, water and sediments. This work studies the adsorption/desorption of the macrolide antibiotic clarithromycin (CLA) for 17 agricultural soils with different edaphic characteristics. The research was carried out using batch-type experiments, with an additional assessment of the specific influence of pH for 6 of the soils. The results show that CLA adsorption reaches between 26 and 95%. In addition, the fit of the experimental data to adsorption models provided values between 1.9 and 19.7 Ln μmol1-n kg-1 for the KF, Freundlich affinity coefficient, and between 2.5 and 10.5 L kg-1 for Kd, distribution constant of Linear model. Regarding the linearity index, n, it varied between 0.56 and 1.34. Desorption showed lower scores than adsorption, with an average of 20%, and with values of 3.1 and 93.0 Ln μmol1-n kg-1 for KF(des) and 4.4 and 95.0 L kg-1 for Kd(des). The edaphic characteristics with the highest influence on adsorption were the silt fraction content and the exchangeable Ca content, while in the case of desorption, they were the total nitrogen, organic carbon, and exchangeable Ca and Mg contents. Regarding the pH, within the range studied (between 3 and 10), its value did not decisively affect the adsorption/desorption process. Overall, the set of these results could be of help to program appropriate measures leading to the retention/elimination of this antibiotic when it reaches the environment as a pollutant.

Uptake and accumulation of emerging contaminants in processing tomato irrigated with tertiary treated wastewater effluent: a pilot-scale study

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.

Ketoprofen as an emerging contaminant: occurrence, ecotoxicity and (bio)removal

Ketoprofen, a bicyclic non-steroidal anti-inflammatory drug commonly used in human and veterinary medicine, has recently been cited as an environmental contaminant that raises concerns for ecological well-being. It poses a growing threat due to its racemic mixture, enantiomers, and transformation products, which have ecotoxicological effects on various organisms, including invertebrates, vertebrates, plants, and microorganisms. Furthermore, ketoprofen is bioaccumulated and biomagnified throughout the food chain, threatening the ecosystem function. Surprisingly, despite these concerns, ketoprofen is not currently considered a priority substance. While targeted eco-pharmacovigilance for ketoprofen has been proposed, data on ketoprofen as a pharmaceutical contaminant are limited and incomplete. This review aims to provide a comprehensive summary of the most recent findings (from 2017 to March 2023) regarding the global distribution of ketoprofen in the environment, its ecotoxicity towards aquatic animals and plants, and available removal methods. Special emphasis is placed on understanding how ketoprofen affects microorganisms that play a pivotal role in Earth's ecosystems. The review broadly covers various approaches to ketoprofen biodegradation, including whole-cell fungal and bacterial systems as well as enzyme biocatalysts. Additionally, it explores the potential of adsorption by algae and phytoremediation for removing ketoprofen. This review will be of interest to a wide range of readers, including ecologists, microbiologists, policymakers, and those concerned about pharmaceutical pollution.

Dissemination of nonsteroidal anti-inflammatory drugs (NSAIDs) and metabolites from wastewater treatment plant to soils and agricultural crops via real-scale different agronomic practices

One of the most consumed pharmaceutical subgroups across the world is nonsteroidal anti-inflammatory drugs (NSAIDs). However, the dissemination of these compounds to the natural environments through agronomic practices is a serious global problem. The hypothesis of this study is to reveal the transition of selected NSAIDs, paracetamol (PAR), diclofenac (DCF), ibuprofen (IBU), and naproxen (NAP) together with six main metabolites, detected in raw/treated wastewater (RWW/TWW) and sewage sludge generated in an urban wastewater treatment plant (WWTP) to soils and agricultural crops (corn, barley, sunflower, and sugar beet) through two widely applied agronomic practices, irrigation with TWW and application of sewage sludge as soil amendment. In other words, the cycles of 10 NSAIDs have been evaluated by simultaneously monitoring their concentrations in RWW/TWW, sewage sludge, soils, and crops. It was determined that the parent compounds and detected metabolites were treated at quite higher removal efficiencies (93.4 - >99.9%) in the studied WWTP, while DCF was eliminated poorly (7.9-52.2%). However, although it changes seasonally for some compounds, it was determined that the concentrations of almost all investigated NSAIDs increased at the determined irrigation points in the discharge channel (DC) where agricultural irrigations were performed. Apart from that, DCF, NAP, and 2-hydroxyibuprofen (2-OH-IBU) were always detected in sewage sludge seasonally up to about 20.5, 11.3, and 3.7 ng/g, respectively. While 2-OH-IBU was determined as the dominant metabolite in RWW, TWW, and sewage sludge, the metabolite of 1-hydroxyibuprofen (1-OH-IBU) was determined as the dominant compound in soils. Although 1-OH-IBU was not detected in TWW and sewage sludge in any season, detecting this metabolite as a common compound in all investigated soils (up to 60.1 ng/kg) reveals that this compound is the primary transformation product of IBU in soils. It was observed that at least one of the metabolites of IBU (1-OH-IBU and/or 2-OH-IBU) was detected in all plants grown (up to 0.75 ng/g), especially during the periods when both agricultural practices were applied. In addition, the detection of 1-OH-IBU with increasing concentrations from root to shoots in corn grown as a result of both agronomic practices shows that this compound has a high translocation potential in the corn plant. Apart from this, it was determined that PAR was detected in corn (up to 43.3 ng/kg) and barley (up to 16.8 ng/kg) within the scope of irrigation with TWW, and NAP was detected in sugar beet (up to 11.2 ng/kg) through sewage sludge application.

A new insight into the potential drivers of antibiotic resistance gene enrichment in the collembolan gut association with antibiotic and non-antibiotic agents

Effects of non-antibiotic pharmaceuticals on antibiotic resistance genes (ARGs) in soil ecosystem are still unclear. In this study, we explored the microbial community and ARGs variations in the gut of the model soil collembolan Folsomia candida following soil antiepileptic drug carbamazepine (CBZ) contamination, while comparing with antibiotic erythromycin (ETM) exposure. Results showed that, CBZ and ETM all significantly influenced ARGs diversity and composition in the soil and collembolan gut, increasing the relative abundance of ARGs. However, unlike ETM, which influences ARGs via bacterial communities, exposure to CBZ may have primarily facilitated enrichment of ARGs in gut through mobile genetic elements (MGEs). Although soil CBZ contamination did not pose an effect on the gut fungal community of collembolans, it increased the relative abundance of animal fungal pathogens contained therein. Soil ETM and CBZ exposure both significantly increased the relative abundance of Gammaproteobacteria in the collembolan gut, which may be used to indicate soil contamination. Together, our results provide a fresh perspective for the potential drivers of non-antibiotic drugs on ARG changes based on the actual soil environment, revealing the potential ecological risk of CBZ on soil ecosystems involving ARGs dissemination and pathogens enrichment.

Selection of indicator contaminants of emerging concern when reusing reclaimed water for irrigation - A proposed methodology

Organic and microbial contaminants of emerging concern (CECs), even though not yet regulated, are of great concern in reclaimed water reuse projects. Due to the large number of CECs and their different characteristics, it is useful to include only a limited number of them in monitoring programs. The selection of the most representative CECs is still a current and open question. This study presents a new methodology for this scope, in particular for the evaluation of the performance of a polishing treatment and the assessment of the risk for the environment and the irrigated crops. As to organic CECs, the methodology is based on four criteria (occurrence, persistence, bioaccumulation and toxicity) expressed in terms of surrogates (respectively, concentrations in the secondary effluent, removal achieved in conventional activated sludge systems, Log K_ow and predicted-no-effect concentration). It consists of: (i) development of a dataset including the CECs found in the secondary effluent, together with the corresponding values of surrogates found in the literature or by in-field investigations; (ii) normalization step with the assignment of a score between 1 (low environmental impact) and 5 (high environmental impact) to the different criteria based on threshold values set according to the literature and experts' judgement; (iii) CEC ranking according to their final score obtained as the sum of the specific scores; and (iv) selection of the representative CECs for the different needs. Regarding microbial CECs, the selection is based on their occurrence and their highest detection frequency in the secondary effluent and in the receiving water, the antibiotic consumption patterns, and recommendations by national and international organisations. The methodology was applied within the ongoing reuse project SERPIC resulting in a list of 30 indicator CECs, including amoxicillin, bisphenol A, ciprofloxacin, diclofenac, erythromycin, ibuprofen, iopromide, perfluorooctane sulfonate (PFOS), sulfamethoxazole, tetracycline, Escherichia coli, faecal coliform, 16S rRNA, sul1, and sul2.

Environmental concerns and bioaccumulation of psychiatric drugs in water bodies - Conventional versus biocatalytic systems of mitigation

The COVID-19 pandemic has brought increments in market sales and prescription of medicines commonly used to treat mental health disorders, such as depression, anxiety, stress, and related problems. The increasing use of these drugs, named psychiatric drugs, has led to their persistence in aquatic systems (bioaccumulation), since they are recalcitrant to conventional physical and chemical treatments typically used in wastewater treatment plants. An emerging environmental concern caused by the bioaccumulation of psychiatric drugs has been attributed to the potential ecological and toxicological risk that these medicines might have over human health, animals, and plants. Thus, by the application of biocatalysis-assisted techniques, it is possible to efficiently remove psychiatric drugs from water. Biocatalysis, is a widely employed and highly efficient process implemented in the biotransformation of a wide range of contaminants, since it has important differences in terms of catalytic behavior, compared to common treatment techniques, including photodegradation, Fenton, and thermal treatments, among others. Moreover, it is noticed the importance to monitor transformation products of degradation and biodegradation, since according to the applied removal technique, different toxic transformation products have been reported to appear after the application of physical and chemical procedures. In addition, this work deals with the discussion of differences existing between high- and low-income countries, according to their environmental regulations regarding waste management policies, especially waste of the drug industry.

Contaminant uptake in wastewater irrigated tomatoes

As population growth and climate change add to the problem of water scarcity in many regions, the argument for using treated wastewater for irrigation is becoming increasingly compelling, which makes understanding the risks associated with the uptake of harmful chemicals by crops crucial. In this study, the uptake of 14 chemicals of emerging concern (CECs) and 27 potentially toxic elements (PTEs) was studied in tomatoes grown in soil-less (hydroponically) and soil (lysimeters) media irrigated with potable and treated wastewater using LC-MS/MS and ICP-MS. Bisphenol S, 2,4 bisphenol F, and naproxen were detected in fruits irrigated with spiked potable water and wastewater under both conditions, with BPS having the highest concentration (0.034-0.134 µg kg^-1 f. w.). The levels of all three compounds were statistically more significant in tomatoes grown hydroponically (<LOQ - 0.137 µg kg^-1 f. w.) than in soil (<LOQ - 0.083 µg kg^-1 f. w.). Their elemental composition shows differences between tomatoes grown hydroponically or in soil and tomatoes irrigated with wastewater and potable water. Contaminants at determined levels showed low dietary chronic exposure. When the health-based guidance values for the studied CECs are determined, results from this study will be helpful for risk assessors.

Uptake of different pharmaceuticals in soil and mycorrhizal artichokes from wastewater

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.

Determining reclaimed water quality thresholds and farming practices to improve food crop yield: A meta-analysis combined with random forest model

Irrigated agricultural systems with reclaimed water (RW) play a crucial role in alleviating global water scarcity and increased food demand. However, appropriate reclaimed water quality thresholds and farming practices to improve food crop yield is virtually unclear. Therefore, for the first time, this study made a large compilation of previous studies using meta-analysis combined with a random forest (RF) model and analyzed the impact of RW versus freshwater (FW) on the yield of food crops (cereals, vegetables, and fruits). It was found that magnesium ion (Mg²⁺), calcium ion (Ca²⁺), electrical conductivity (EC), total nitrogen (TN), and potential of hydrogen (pH) were the most important factors for RW quality indicators. Based on the results, water managers should establish more conservative RW quality thresholds to promote food crop production, especially for salts and pollutants in RW. Compared to international water quality standards, it could be slightly relaxed the restrictions of TN in RW. The optimal farming practices obtained that irrigation amount of the mixed RW and FW (RW + FW) was from 1000 m³ ha^-1 to 5000 m³ ha^-1, and the cultivation period was no more than three years. Flood irrigation (FI) and drip irrigation (DI) for cereals were also recommended. Finally, a comparison of the determined results from this method with other scenarios published, finding a good agreement.

Long-term effects on the agroecosystem of using reclaimed water on commercial crops

The use of reclaimed water for crop irrigation has been proposed as a suitable alternative for farmers in the coastal areas of Mediterranean countries, which suffer from greater water scarcity. In this work we study the impact on the water-soil-plant continuum of using reclaimed water for commercial crops irrigated over a long period, as well as the human risks associated with consuming the vegetables produced. Forty-four CECs were identified in the reclaimed water used for crop irrigation. Of these, twenty-four CECs were identified in the irrigated soil samples analysed. Tramadol, ofloxacin, tonalide, gemfibrozil, atenolol, caffeine, and cetirizine were the pharmaceuticals detected at the highest levels in the water samples (between 11 and 44 μg/L). The CECs with the highest average soil concentrations were tramadol (14.6 μg/kg), followed by cetirizine (13.2 μg/kg) and clarithromycin (12.7 μg/kg). In the irrigated vegetable samples analysed over the study period, carbamazepine, lidocaine, and caffeine were only detected at levels from 0.1 to 1.7 μg/kg. The CEC accumulation rate detected in the edible parts of the vegetables permanently irrigated with reclaimed water was very low (~1 %), whereas it was 33 % in the soils. The results revealed that consuming fruits harvested from plants irrigated for a long period with reclaimed water does not represent a risk to human health, opening the door to a circular economy of water. Nevertheless, for crop irrigation, future studies need to be conducted over longer periods and in other matrices to provide more scientific data on the safety of using reclaimed water.

Uptake, Metabolism and Accumulation of Tire Wear Particle-Derived Compounds in Lettuce

Tire wear particle (TWP)-derived compounds may be of high concern to consumers when released in the root zone of edible plants. We exposed lettuce plants to the TWP-derived compounds diphenylguanidine (DPG), hexamethoxymethylmelamine (HMMM), benzothiazole (BTZ), N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine (6PPD), and its quinone transformation product (6PPD-q) at concentrations of 1 mg L-1 in hydroponic solutions over 14 days to analyze if they are taken up and metabolized by the plants. Assuming that TWP may be a long-term source of TWP-derived compounds to plants, we further investigated the effect of leaching from TWP on the concentration of leachate compounds in lettuce leaves by adding constantly leaching TWP to the hydroponic solutions. Concentrations in leaves, roots, and nutrient solution were quantified by triple quadrupole mass spectrometry, and metabolites in the leaves were identified by Orbitrap high resolution mass spectrometry. This study demonstrates that TWP-derived compounds are readily taken up by lettuce with measured maximum leaf concentrations between ∼0.75 (6PPD) and 20 μg g-1 (HMMM). Although these compounds were metabolized in the plant, we identified several transformation products, most of which proved to be more stable in the lettuce leaves than the parent compounds. Furthermore, continuous leaching from TWP led to a resupply and replenishment of the metabolized compounds in the lettuce leaves. The stability of metabolized TWP-derived compounds with largely unknown toxicities is particularly concerning and is an important new aspect for the impact assessment of TWP in the environment.

Effects of irrigation water quality on the presence of pharmaceutical and personal care products in topsoil and vegetables in greenhouses

The presence of pharmaceutical and personal care products (PPCPs) in the environment has harmful effects on humans and the ecosystem. Reclaimed water irrigation may introduce PPCPs into the agricultural system. Here, a greenhouse experiment investigated the impact of reclaimed water irrigation on PPCP levels in the edible parts of vegetables and topsoil in the North China Plain in 2015 and 2016. Three treatment protocols were applied to each vegetable: irrigation with reclaimed water, irrigation with groundwater, and mixed irrigation with groundwater and reclaimed water (1:1, v/v). The total concentrations of 10 PPCPs in the topsoil (0-20 cm deep) and vegetables were 4.06-19.0 and 2.33-189 μg/kg, respectively. Among the target PPCPs, acetyl-sulfamethoxazole (AC-SMX) had the highest concentration in both soil and vegetables (0.23-10.8 and 1.56-116 μg/kg, respectively). The total concentration of the 10 PPCPs among cabbage, cauliflower, carrot, and cucumber were 13.1-28.1, 10.3-28.3, 2.33-4.04, and 110-189 μg/kg, respectively. The total hazard quotients for the mixture of target PPCPs across all vegetables were 0.0007 and 0.0003 for toddlers and adults, respectively. Compared with groundwater irrigation, reclaimed water irrigation did not evidently affect the vegetable yields, soil-vegetable PPCP concentrations, and BCFs. In this study, we found no potential hazard to human health when people consumed vegetables grown using reclaimed water irrigation.

Occurrence and risk assessment of pharmaceuticals in surface waters of the Middle East and North Africa: A review

Pharmaceutical compounds in surface water are perceived as contaminants of emerging concern due to their impacts on the aquatic environment and human health. The risk associated with these compounds has not been quantified in the Middle East and North Africa (MENA). This review identified that 210 pharmaceutical compounds have been analyzed in MENA water compartments between 2008 and 2022. In fact, 151 of these substances were detected in at least one of 13 MENA countries where occurrence studies had been conducted. Antibiotics claimed the highest number of pharmaceuticals detected with concentrations ranging between 0.03 and 66,400 ng/L (for Thiamphenicol and Spiramycin respectively). To investigate whether any of these compounds exert an ecological, human health, or antibiotic resistance risk, a screening-level risk assessment was performed in surface water matrices using maximum, median, and minimum concentrations. 39 and 8 detected pharmaceuticals in MENA surface waters posed a possible risk on aquatic ecosystems and human health respectively. Extremely high risk quotients (>1000) for six pharmaceuticals (17β estradiol, spiramycin, diclofenac, metoprolol, ethinylestradiol, and carbamazepine) were enumerated based on maximal concentrations implying an alarming risk on aquatic toxicity. Moreover, hormones posed the highest possible risk on human health whether ingested through drinking water or fish (e.g., 17β-estradiol had a health risk quotient of 2880 for children). Spiramycin showed a high risk of antibiotic resistance with a risk quotient of 133. This review serves as a basis for future prioritization studies and regulatory guidelines in the MENA region to minimize the risks of the identified compounds.

Soil self-cleaning capacity: Removal of organic compounds during sub-surface irrigation with sewage effluent

Globally, the reuse of treated sewage effluent for irrigation purposes is increasingly encouraged as a practical solution against the mismatch between the demand for and availability of freshwater resources. The reuse of sewage effluent for sub-surface irrigation (SSI) in agriculture serves the dual purpose of supplying water to crops and diminishing emissions of contaminants of emerging concern (CoECs) into surface water. To investigate such reuse, in a real scale cropland with SSI using sewage effluent, from September 2017 to March 2019 including the extremely dry year 2018, residues were followed of 133 CoECs as related to their physicochemical properties and quantified by liquid chromatography coupled to high-resolution mass spectrometry. Of the 133 target CoECs, 89 were retrieved in the field, most non-detect CoECs have low persistency. During the growing season with sub-surface irrigation, CoECs spread to the shallow groundwater and rhizosphere. Significantly lower concentrations are found between infiltration pipes as compared to directly next to the pipes in shallow groundwater for all persistency-mobility classes. CoECs belonging to the class pm (low persistency and low mobility) or class PM (high persistency and high mobility) class show no change amongst their removal in the rhizosphere and groundwater in a dry versus normal year. CoECs belonging to the class pM (low persistency and high mobility) show high seasonal dynamics in the rhizosphere and shallow groundwater, indicating that these CoECs break down. CoECs of the class Pm (high persistency and low mobility) only significantly build up in the rhizosphere next to infiltration pipes. Climatic conditions with dry summers and precipitation surplus and drainage in winter strongly affect the fate of CoECs. During the dry summer of 2018 infiltrated effluent is hardly diluted, resulting in significantly higher concentrations for the CoECs belonging to the classes pM and Pm. After the extremely dry year of 2018, cumulative concentrations are still significantly higher, while after a normal year during winter precipitation surplus removes CoECs. For all persistency-mobility classes in the shallow groundwater between the pipes, we find significant removal efficiencies. For the rhizosphere between the pipes, we find the same except for Pm. Next to the pipes however we find no significant removal for all classes in both the rhizosphere and shallow groundwater and even significant accumulation for Pm. For this group of persistent moderately hydrophobic CoECs risk characterization ratio's were calculated for the period of time with the highest normalized concentration. None of the single-chemical RCRs are above one and the ΣRCR is also far below one, implying sufficiently safe ambient exposures. Overall the deeper groundwater (7.0-11.8 m below soil surface) has the lowest response to the sub-surface irrigation for all persistency-mobility. When adopting a SSI STP effluent reuse system care must be taken to monitor the CoECs that are (moderately) hydrophobic as these can build up in the SSI system. For the deeper groundwater and for the discharge to the surface water, we find significant removal for the pM and the PM class but not for other classes. In conclusion, relatively high removal efficiencies are shown benefiting the surface waters that would otherwise receive the STP effluent directly.

The role of the sewer system in estimating urban emissions of chemicals of emerging concern

The use of chemicals by society has resulted in calls for more effective control of their emissions. Many of these chemicals are poorly characterized because of lacking data on their use, environmental fate and toxicity, as well as lacking detection techniques. These compounds are sometimes referred to as contaminants of emerging concern (CECs). Urban areas are an important source of CECs, where these are typically first collected in sewer systems and then discharged into the environment after being treated in a wastewater treatment plant. A combination of emission estimation techniques and environmental fate models can support the early identification and management of CEC-related environmental problems. However, scientific insight in the processes driving the fate of CECs in sewer systems is limited and scattered. Biotransformation, sorption and ion-trapping can decrease CEC loads, whereas enzymatic deconjugation of conjugated metabolites can increase CEC loads as metabolites are back-transformed into their parent respective compounds. These fate processes need to be considered when estimating CEC emissions. This literature review collates the fragmented knowledge and data on in-sewer fate of CECs to develop practical guidelines for water managers on how to deal with in-sewer fate of CECs and highlights future research needs. It was assessed to what extent empirical data is in-line with text-book knowledge and integrated sewer modelling approaches. Experimental half-lives (n = 277) of 96 organic CECs were collected from literature. The findings of this literature review can be used to support environmental modelling efforts and to optimize monitoring campaigns, including field studies in the context of wastewater-based epidemiology.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11157-022-09638-9.

Removal of contaminants of emerging concern from secondary-effluent reverse osmosis retentates by continuous supercritical water oxidation- parametric study and conceptual design

The continuous removal of TOC and the degradation efficiency of carbamazepine and 17β-estradiol were investigated using actual secondary municipal-effluent RO-retentate solutions. A specific set of operating parameters were applied within the supercritical water oxidizing conditions: temperature range 420-480 °C, 25.1 MPa, hydraulic retention time (HRT) of 1-2 min, excess oxidant molar-ratio of 3-10 and presence of a homogenous catalyst (IPA) at 50-100 mg/L. > 99% organic carbon mineralization, along with complete degradation of model pollutants, was observed at 450 °C/1 min/OC= 5-10 and 100 mgIPA/L. The outlet estrone concentration, 1.03 ± 1.14 ng/L, representing estrogenic pollutants, dropped to the "no effect" range. A model for a SCWO plant treating secondary-municipal-effluent-RO-retentate for a city of 100,000 capita-equivalent was developed, based on a shell & tube SCWO flow reactor, showing > 75% energy-efficiency. The model yielded that for the extreme case of a zero caloric-value feed-solution, the total OPEX and CAPEX would be < $6.0 ± 2.5 per m³ of secondary effluents, i.e., two orders of magnitude lower than the reported environmental shadow-price associated with CECs (contaminants of emerging concern). Further work is required on the continuous and efficient separation of the salt-matrix, which can lead to higher overall heat transfer coefficients and enable further reduction in capital costs.

Wastewater-derived organic contaminants in fresh produce: Dietary exposure and human health concerns

Irrigation with reclaimed wastewater is a growing practice aimed at conserving freshwater sources, especially in arid and semiarid regions. Despite the apparent advantages to water management, the practice of irrigation with reclaimed wastewater exposes the agroenvironment to contaminants of emerging concern (CECs). In this report, we estimated the unintentional dietary exposure of the Israeli population (2808 participants) to CECs from consumption of produce irrigated with reclaimed wastewater using detailed dietary data obtained from a National Health and Nutrition Survey (Rav Mabat adults; 2014-2016). Human health risk analyses were conducted based on acceptable daily intake (ADI) and threshold of toxicological concern (TTC) approaches. The highest unintentional exposure to wastewater-borne CECs was found to occur through the consumption of leafy vegetables. All analyzed CECs exhibited hazard quotients <1 for the mean- and high-exposure scenarios, indicating no human health concerns. However, for the extreme exposure scenario, the anticonvulsant agents lamotrigine and carbamazepine, and the carbamazepine metabolite epoxide-carbamazepine exhibited the highest exposure levels of 29,100, 27,200, and 19,500 ng/person (70 kg) per day, respectively. These exposure levels exceeded the TTC of lamotrigine and the metabolite epoxide-carbamazepine, and the ADI of carbamazepine, resulting in hazard quotients of 2.8, 1.1, and 1.9, respectively. According to the extreme estimated scenario, consumption of produce irrigated with reclaimed wastewater (leafy vegetables in particular) may pose a threat to human health. Minimizing irrigation of leafy vegetables using reclaimed wastewater and/or improving the quality of the reclaimed wastewater using an advanced treatment would significantly reduce human dietary exposure to CECs.

Desorption of pharmaceuticals and illicit drugs from different stabilized sludge types across pH

Pharmaceutical and illicit drug residues in sewage sludge may present important risks following direct application to agricultural soils, potentially resulting in uptake by plants. Leaching/desorption tests were performed on different types of stabilized sewage sludge originating from multiple treatment technologies in the Slovak Republic. Acid rain and base-rich condition of soil with different pH conditions were simulated to model the effect of widely varying pH (pH 2, 4, 7, 9, and 12) on the leaching/desorption of pharmaceuticals and illicit drugs. Twenty-nine of 93 target analytes were found above the limit of quantification in sludge or associated leachates. Total desorbed amounts of pharmaceuticals and illicit drugs ranged from 810 to 4000 µg/kg, and 110 to 3600 µg/kg of the dry mass of anaerobic and aerobic sludge, respectively. Desorbed fractions were calculated as these values are normalized to initial sludge concentration and, therefore, were more suitable for qualitative description of the behavior of individual compounds. Using principal component analysis, qualitative analysis of the desorbed fraction confirmed the differences among sludge types, pharmaceuticals, and desorption pH. Desorbed fractions could not be related to the octanol/water distribution coefficient. Desorbed fractions also did not reflect the expected ionization of studied molecules unless converted into their relative values. Generally, the lowest mobility was observed within the environmentally relevant pH range of 4-9, and high pH generally resulted in high desorption, especially in anaerobically stabilized sludges.

Uptake of Pharmaceutical Pollutants and Their Metabolites from Soil Fertilized with Manure to Parsley Tissues

Manure is a major source of soil and plant contamination with veterinary drugs residues. The aim of this study was to evaluate the uptake of 14 veterinary pharmaceuticals by parsley from soil fertilized with manure. Pharmaceutical content was determined in roots and leaves. Liquid chromatography coupled with tandem mass spectrometry was used for targeted analysis. Screening analysis was performed to identify transformation products in the parsley tissues. A solid-liquid extraction procedure was developed combined with solid-phase extraction, providing recoveries of 61.9–97.1% for leaves and 51.7–95.6% for roots. Four analytes were detected in parsley: enrofloxacin, tylosin, sulfamethoxazole, and doxycycline. Enrofloxacin was detected at the highest concentrations (13.4–26.3 ng g⁻¹). Doxycycline accumulated mainly in the roots, tylosin in the leaves, and sulfamethoxazole was found in both tissues. 14 transformation products were identified and their distribution were determined. This study provides important data on the uptake and transformation of pharmaceuticals in plant tissues.

Fate of contaminants of emerging concern in the reclaimed wastewater-soil-plant continuum

Reclaimed wastewater irrigation, a common agricultural practice in water-scarce regions, chronically exposes the agricultural environment to a wide range of contaminants of emerging concern (CECs) including pharmaceuticals and personal care products. Here we provide new data and insights into the processes governing the translocation of CECs in the irrigation water-soil-plant continuum based on a comprehensive dataset from 445 commercial fields irrigated with reclaimed wastewater. We report on CEC exposures in irrigation water, soils, and edible produce (leafy greens, carrots, potatoes, bananas, tomatoes, avocados, and citrus fruits). Our data show that CEC concentrations in irrigation water and their physiochemical properties (mainly charge and lipophilicity) are the main factors governing their translocation and accumulation in the soil-plant continuum. CECs exhibiting the highest detection frequency in plants (lamotrigine, venlafaxine, and carbamazepine) showed a reduction in their leaf accumulation factor with increasing soil organic matter content. The higher soil organic matter likely reduced the available CEC concentration in the soil solution due to soil-CEC interactions, leading to reduced uptake. Interestingly, the concentration of carbamazepine in the leaves showed a saturation-like trend when plotted against its concentration in the soils. This probably resulted from steady-state conditions when uptake equals in-planta decomposition. Our data indicate that due to continuous reclaimed wastewater irrigation, the soil acts as a sink for CECs. CECs in the soil reservoir can be desorbed into the soil solution during the rainy season and be taken up by rain-fed crops.

The status of potable water reuse implementation

A review of the current status of direct and indirect potable water reuse (DPR/IPR) implementation has been conducted, focusing on the regulatory and practical aspects and with reference to the most recent published literature. The review encompasses (a) the principal contaminant types, their required removal and the methods by which their concentration is monitored, (b) regulatory approaches and stipulations in assessing/ratifying treatment schemes and maintaining treated water quality, and (c) existing full-scale installations. Analytical methods discussed include established in-line monitoring tools, such as turbidity measurement, to more recent polymerase chain reaction (PCR)-based assay methods for microbial detection. The key risk assessment tools of quantitative microbial risk assessment (QMRA) and water safety plans (WSPs) are considered in relation to their use in selecting/ratifying treatment schemes, and the components of the treatment schemes from 40 existing IPR/DPR installations summarised. Five specific schemes are considered in more detail. The review reveals:Whilst there are a number of ongoing projects where RO is not used because of the challenge imposed by disposal of RO concentrate, the prevalence of the sequential RO-UV combination implies the importance of quantifying the impact of process upsets on these unit operations.

Contaminants of emerging concerns in recycled water: Fate and risks in agroecosystems

Recycled water (RW) has been increasingly recognized as a valuable source of water for alleviating the global water crisis. When RW is used for agricultural irrigation, many contaminants of emerging concern (CECs) are introduced into the agroecosystem. The ubiquity of CECs in field soil, combined with the toxic, carcinogenic, or endocrine-disrupting nature of some CECs, raises significant concerns over their potential risks to the environment and human health. Understanding such risks and delineating the fate processes of CECs in the water-soil-plant continuum contributes to the safe reuse of RW in agriculture. This review summarizes recent findings and provides an overview of CECs in the water-soil-plant continuum, including their occurrence in RW and irrigated soil, fate processes in agricultural soil, offsite transport including runoff and leaching, and plant uptake, metabolism, and accumulation. The potential ecological and human health risks of CECs are also discussed. Studies to date have shown limited accumulation of CECs in irrigated soils and plants, which may be attributed to multiple attenuation processes in the rhizosphere and plant, suggesting minimal health risks from RW-fed food crops. However, our collective understanding of CECs is rather limited and knowledge of their offsite movement and plant accumulation is particularly scarce for field conditions. Given a large number of CECs and their occurrence at trace levels, it is urgent to develop strategies to prioritize CECs so that future research efforts are focused on CECs with elevated risks for offsite contamination or plant accumulation. Irrigating specific crops such as feed crops and fruit trees may be a viable option to further minimize potential plant accumulation under field conditions. To promote the beneficial reuse of RW in agriculture, it is essential to understand the human health and ecological risks imposed by CEC mixtures and metabolites.

Structural and Metabolic Profiling of Lycopersicon esculentum Rhizosphere Microbiota Artificially Exposed at Commonly Used Non-Steroidal Anti-Inflammatory Drugs

In this study, the effect of common non-steroidal anti-inflammatory drugs on Lycopersicon esculentum rhizosphere microbiota was monitored. The experiments were performed with artificially contaminated soil with ibuprofen (0.5 mg·kg⁻¹), ketoprofen (0.2 mg·kg⁻¹) and diclofenac (0.7 mg·kg⁻¹). The results evidenced that the rhizosphere microbiota abundance decreased especially under exposure to diclofenac (187–201 nmol·g⁻¹ dry weight soil) and ibuprofen (166–183 nmol·g⁻¹ dry weight soil) if compared with control (185–240 nmol·g⁻¹ dry weight soil), while the fungal/bacteria ratio changed significantly with exposure to diclofenac (<27%) and ketoprofen (<18%). Compared with control samples, the average amount of the ratio of Gram-negative/Gram-positive bacteria was higher in rhizosphere soil contaminated with ibuprofen (>25%) and lower in the case of diclofenac (<46%) contamination. Carbon source consumption increased with the time of assay in case of the control samples (23%) and those contaminated with diclofenac (8%). This suggests that rhizosphere microbiota under contamination with diclofenac consume a higher amount of carbon, but they do not consume a larger variety of its sources. In the case of contamination with ibuprofen and ketoprofen, the consumption of carbon source presents a decreasing tendency after day 30 of the assay. Rhizosphere microbiota emitting volatile organic compounds were also monitored. Volatile compounds belonging to alcohol, aromatic compounds, ketone, terpene, organic acids, aldehyde, sulphur compounds, esters, alkane, nitrogen compounds, alkene and furans were detected in rhizosphere soil samples. Among these, terpene, ketone, alcohol, aromatic compounds, organic acids and alkane were the most abundant compound classes (>75%), but their percentage changed with exposure to diclofenac, ketoprofen and ibuprofen. Such changes in abundance, structure and the metabolic activity of Lycopersicon esculentum rhizosphere microbiota under exposure to common non-steroidal anti-inflammatory drugs suggest that there is a probability to also change the ecosystem services provided by rhizosphere microbiota.

Uptake, Occurrence, and Effects of Nonsteroidal Anti-Inflammatory Drugs and Analgesics in Plants and Edible Crops

The plant uptake of pharmaceuticals that include nonsteroidal anti-inflammatory drugs (NSAIDs) and analgesics from contaminated environment has benefits and drawbacks. These pharmaceuticals enter plants mostly through irrigation with contaminated water and application of sewage sludge as soil fertilizer. Aquatic plants withdraw these pharmaceuticals from water through their roots. Numerous studies have observed the translocation of these pharmaceuticals from the roots into the aerial tissues. Furthermore, the occurrence of the metabolites of NSAIDs in plants has been observed. This article provides an in-depth critical review of the plant uptake of NSAIDs and analgesics, their translocation, and toxic effects on plant species. In addition, the occurrence of metabolites of NSAIDs in plants and the application of constructed wetlands using plants for remediation are reviewed. Factors that affect the plant uptake and translocation of these pharmaceuticals are examined. Gaps and future research are provided to guide forthcoming investigations on important aspects that worth explorations.