A review of the occurrence of pharmaceuticals and personal care products in Indian water bodies

Enrofloxacin exposure induces anxiety-like behavioral responses in zebrafish by affecting the microbiota-gut-brain axis

The ubiquitous presence of antibiotic residues in aqueous environments poses a great potential threat to aquatic organisms. Nevertheless, the behavioral effects of environmentally realistic levels of antibiotics remain poorly understood in fish species. In this study, the behavioral impacts of enrofloxacin, one of typical fluoroquinolone antibiotics that is frequently detected in aquatic environments, were evaluated by the classic light-dark test (LDT) and novel tank task (NTT) in zebrafish. Furthermore, the effects of enrofloxacin exposure on the microbiota-gut-brain axis were also assessed to reveal potential affecting mechanisms underlying the behavioral abnormality observed. Our results demonstrated that zebrafish exposed to 60 μg/L enrofloxacin for 28 days took significantly longer to enter the stressful area of the testing tank and spent significantly less time there in both the LDT and NTT, indicating abnormal anxiety-like behaviors induced by the exposure. In addition, exposure to enrofloxacin at 6 and 60 μg/L resulted in a significant elevation in Bacteroidetes and a marked decline in the Firmicutes/Bacteroidetes ratio of the gut microbiota. Moreover, the intestinal contents of interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), glucagon-like peptide 1 (GLP-1), and 5-hydroxytryptamine (5-HT) in zebrafish were significantly upregulated, whereas those of plasma adrenocorticotropic hormone (ACTH) and cortisol (COR) were markedly downregulated upon enrofloxacin exposure. Incubation of zebrafish with a high dose of enrofloxacin (60 μg/L) also resulted in evident increases in the contents of corticotropin-releasing hormone (CRH), brain-derived neurotrophic factor (BDNF), and neuropeptide Y (NPY) in the brain. Fortunately, no significant alteration in the expression of glial fibrillary acidic protein (GFAP) was detected in the brain after enrofloxacin exposure. Our findings suggest that the disruption of the microbiota-gut-brain axis may account for enrofloxacin-induced anxiety-like behaviors in zebrafish. Since the disruption of microbiota-gut-brain axis may give rise to various clinical symptoms, the health risk of antibiotic exposure deserves more attention.

Treatment Trends and Combined Methods in Removing Pharmaceuticals and Personal Care Products from Wastewater-A Review

When discharged into wastewater, pharmaceuticals and personal care products (PPCPs) become microorganic contaminants and are among the largest groups of emerging pollutants. Human, animal, and aquatic organisms' exposures to PPCPs have linked them to an array of carcinogenic, mutagenic, and reproductive toxicity risks. For this reason, various methods are being implemented to remove them from water bodies. This report critically reviews these methods and suggests improvements to removal strategies. Biological, physical, and chemical methods such as biological degradation, adsorption, membrane filtration, and advanced electrical and chemical oxidation are the common methods used. However, these processes were not integrated into most studies to take advantage of the different mechanisms specific to each process and are synergistic in the removal of the PPCPs that differ in their physical and chemical characteristics (charge, molecular weight, hydrophobicity, hydrogen bonding, structure). In the review articles published to date, very little information is available on the use of such integrated methods for removing PPCPs. This report attempts to fill this gap with our knowledge.

Factors affecting the hydrolysis of the antibiotic amoxicillin in the aquatic environment

The environmental fate of the frequently used broad-spectrum β-lactam antibiotic amoxicillin (AMX) is of high concern regarding the potential evolution of antimicrobial resistance (AMR). Moreover, it is known that AMX is prone to hydrolysis, yielding a variety of hydrolysis products (HPs) with yet unknown effects. Studies to identify those HPs and investigate their formation mechanisms have been reported but a long-term study on their stability in real water samples was missing. In this regard, we investigated the hydrolysis of AMX at two concentration levels in four distinct water types under three different storage conditions over two months. Concentrations of AMX and four relevant HPs were monitored by an LC-MS/MS method revealing pronounced differences in the hydrolysis rate of AMX in tap water and mineral water on the one hand (fast) and surface water on the other (slow). In this context, the occurrence, relative intensities, and stability of certain HPs are more dependent on the water type than on the storage condition. As clarified by ICP-MS, the main difference between the water types was the content of the metals copper and zinc which are supposed to catalyze AMX hydrolysis demonstrating an effective method to degrade AMX at ambient conditions.

Evaluating chemicals of emerging concern in the Ganga River at the two major cities Prayagraj and Varanasi through validated analytical approaches

Evaluating environmental water quality means to assess and protect the environment against unfriendly impacts from various organic impurities emerging from industrial emissions and those released during harvesting. Potential risks related with release of polycyclic aromatic hydrocarbons (PAHs), pesticides and pharmaceuticals (PhAcs), and personal care products (PCPs) into the environment have turned into an increasingly serious issue in ecological safety. Monitoring helps in control of chemicals and ecological status compliance to safeguard specific water uses, for example, drinking water abstraction. A longitudinal review was carried out for 55 different persistent organic pollutants (POPs) for the Ganga River which passes through the urban areas of Prayagraj and Varanasi, India, through validated analytical approaches and measurement uncertainty (MU) estimation to assess their potential use for routine analysis. Furthermore, environmental risk assessment (ERA) carried out in the present study has revealed risk quotient (RQ) higher than 1 in a portion of the aquatic bodies. Using a conservative RQ strategy, POPs were assessed for having extensive risks under acute and chronic exposure, proposing that there is currently critical ecological risk identified with these compounds present in the Ganga River. In general, these outcomes demonstrate a significant contribution for focusing on measures and feasible techniques to minimize the unfavorable effects of contaminants on the aquatic environment.

Origin, transport and ecological risk assessment of illicit drugs in the environment - A review

Illicit drugs are a novel group of emerging pollutants. A growing global environmental load and ecological risk is created by the ongoing release of these toxins into the environment. Conventional water processing plants fail to completely remove drugs of abuse from both surface water and wastewater. The origin, environmental fate and ecological repercussions of illicit drugs, despite their detection in surface waterways around the world, are not well understood. In this review, illicit drug detections in potable water, surface water and wastewater globally have been studied during the past 15 years in order to establish a baseline for future years. The most common drugs with abuse potential detected in different sources of potable and surface water were methadone (0.12-22.7 ng/L), cocaine (0.05-506.6 ng/L), benzoylecgonine (0.07-1019 ng/L), amphetamine (1.4-342.6 ng/L), and codeine (0.002-42 ng/L). The bulk of research only looked at a small number of drugs of abuse, indicating that despite widespread use, a large spectrum of these intoxicants has yet to be detected. This review focuses on the origin of illicit drug contaminants in water bodies, air, and soil, their persistence in the environment, and the typical concentrations at which they occur in the environment. The impact of these drugs on aquatic organisms like Elliptio complanata mussels, crayfish and zebrafish has also been reviewed.

Global distribution of microplastic contaminants in aquatic environments and their remediation strategies

This review describes the occurrence and distribution of microplastics in freshwater and marine environments in recent years (2017-2022). Use of microplastics often results in contamination of aquatic environments, threatens biodiversity, and creates the need for environmental remediation. Such remediation strategies can involve primary, secondary, and tertiary treatments. Tertiary treatment is a frequent research subject due to its high efficiency and the possibility for advancements and enhancements. This study discusses tertiary treatments with remediation efficiencies of 95% and greater and their advantages, disadvantages, and future perspectives. Biochar-mediated remediation of microplastics is an effective method that may be able to achieve efficiencies approaching 100%. The study concludes by exploring methods of removing microplastics, including constructed wetlands and biochar, which offer high efficiency. PRACTITIONER POINTS: Tertiary treatments are an effective microplastic remediation strategy applicable succeeding secondary or primary treatments or as an individual remediation strategy. Biochar is a highly efficient adsorbent for microplastic remediation from aquatic environment with eco-friendly aspect and reusability. Modifications in tertiary treatments and enhancement in remediation efficiency are still a subject of research for future studies.

Updated knowledge, partitioning and ecological risk of pharmaceuticals and personal care products in global aquatic environments

Over the last few decades, the occurrence of pharmaceuticals and personal care products (PPCPs) in aquatic environments has generated increasing public concern. In this review, data on the presence of PPCPs in environmental compartments from the past few years (2014-2022) are summarized by carrying out a critical survey of the partitioning among water, sediment, and aquatic organisms. From the available articles on PPCP occurrence in the environment, in Web of Science and Scopus databases, 185 articles were evaluated. Diclofenac, carbamazepine, caffeine, ibuprofen, ciprofloxacin, and sulfamethoxazole were reported to occur in 85% of the studies in at least one of the mentioned matrices. Risk assessment showed a moderate to high environmental risk for these compounds worldwide. Moreover, bioconcentration factors showed that sulfamethoxazole and trimethoprim can bioaccumulate in aquatic organisms, while ciprofloxacin and triclosan present bioaccumulation potential. Regarding spatial distribution, the Asian and European continents presented most studies on the occurrence and effects of PPCPs on the environment, while Africa and Asia are the most contaminated continents. In addition, the impact of COVID-19 on environmental contamination by PPCPs is discussed.

Complex behavior between microplastic and antibiotic and their effect on phosphorus-removing Shewanella strain during wastewater treatment

Owing to their widespread application and use, microplastics (MPs) and antibiotics coexist in the sewage treatment systems. In this study, the effects and mechanisms of the combined stress of MPs and ciprofloxacin (CIP) on phosphorus removal by phosphorus-accumulating organisms (PAOs) were investigated. This study found that the four types of MPs and CIP exhibited different antagonistic effects on the inhibition of phosphorus removal by PAO. MPs reduced the effective concentration of CIP through adsorption and thus reduced its toxicity, which was affected by the biofilms on MPs. In addition, CIP may cause PAO to produce more extracellular polymeric substances, which reduces the physical and oxidative stress of MPs on PAO. Our results are helpful as they increase the understanding of the effects of complex emerging pollutants in sewage systems and propose measures to strengthen the biological phosphorus removal in sewage treatment processes.

Removal of pharmaceuticals by vertical flow constructed wetland with different configurations: Effect of inlet load and biochar addition in the substrate

Pharmaceuticals (PCs) residues are considered an emerging threat to the environment due to their persistency, ecotoxicity and bioaccumulative nature. To study the PC (amoxicillin, AMX; caffeine, CF; ibuprofen, IBU) removal efficiency of vertical flow constructed wetland (VFCW), three setups of VFCWs were configured: SB (substrate matrix + biochar (BC)); SBP (substrate matrix + BC + plant); SP (substrate matrix + plant) and changes in effluent PC load was estimated at 24, 48, 72, 96, 120, 144 and 168 h intervals. SBP with an influent load of 1,000 μg L^-1 showed the maximum removals of 75.51% (AMX), 87.53% (CF), and 79.93% (IBU) significantly higher than that of SB and SP (p < 0.00). Results showed an inverse relationship between removal efficacy and influent PCs loading. The average removal (%) by VFCWS (of all studied setups) was in the order: 66.20 > 47.88 > 39.0 (IBU), 56.56 > 42.12 > 34.36 (AMX), and 74.13 > 64.0 > 52.07 (CF) with 1,000, 5,000 > 10,000 μg L^-1 influent load, respectively. The maximum removal of COD, NH₄⁺-N, and NO₃-N was recorded at 88.8%, 83.1%, and 64.9%, respectively in SBP, and their removal was hardly affected by influent PC concentration. In summary, planted VFCW spiked with BC could be a viable approach for the removal of PCs in wastewater. The impact of PC load on plant toxicity in VFCWs can be taken as a research problem for future work in this series.

Global groundwater vulnerability for Pharmaceutical and Personal care products (PPCPs): The scenario of second decade of 21st century

The global production of PPCPs have increased by multiple folds promoting excessive exposure of its metabolites to humans via different aquatic systems. The higher residence time of toxic precursors of these metabolites pose direct human health risk. Among the different aquatic systems, the contamination of groundwater by PPCPs is the most concerning threat. This threat is especially critical considering the lesser oxidizing potential of the groundwater as compared to freshwater/river water. A major challenge also arises due to excessive dependency of the world's population on groundwater, which is exponentially increasing with time. This makes the identification and characterization of spatial contamination hotspots highly probabilistic as compared to other freshwater systems. The situation is more vulnerable in developing countries where there is a reported inadequacy of wastewater treatment facilities, thereby forcing the groundwater to behave as the only available sequestrating sink for all these contaminants. With increased consumption of antibiotics and other pharmaceuticals compounds, these wastes have proven capability in terms of enhancing the resistance among the biotic community of the soil systems, which ultimately can become catastrophic and carcinogenic in near future. Recent studies are supporting the aforementioned concern where compounds like diclofenac (analgesic) have attained a concentration of 1.3 mgL^-1 in the aquifer systems of Delhi, India. The situation is far worse for developed nations where prolonged and indiscriminate usage of antidepressants and antibiotics have life threating consequences. It has been confirmed that certain compounds like ofloxacin (antibiotics) and bis-(2-ethylhexyl)phthalate are present in some of the most sensitive wells/springs of the United States and Mexico. The current trend of the situation has been demonstrated by integrating a comparative approach of the published literatures in last three years. This review provides first-hand information report for formulating a directive policy framework for tackling PPCPs issues in the groundwater system.

Soil degradation kinetics of oxybenzone (Benzophenone-3) and toxicopathological assessment in the earthworm, Eisenia fetida

A preponderance of recent evidence indicates that oxybenzone and other personal-care product chemicals threaten the biota inhabiting various ecological niches. What is understudied is the ecotoxicological impact of oxybenzone, a UV filter in sunscreens and anti-aging products, to terrestrial/soil organisms that are keystone species in these habitats. In the present study, acute exposure (14-day) to oxybenzone resulted in earthworm mortality (LC₅₀ of 364 mg/kg) and growth rate inhibition. Environmentally relevant concentration of oxybenzone (3.64, 7.28 and 36.4 mg/kg) at exposures of 7-day, 14-day, 28-day induced oxidative stress and neurotoxicity followed by perturbations in reproduction processes and changes in vital organs. Decreased levels of superoxide dismutase (SOD) and catalase (CAT) activity were statistically lower than controls (p < 0.05) on day 14 for all three concentrations, while glutathione-s-transferase (GST) activity was significantly elevated from controls on days 7 and 14. On day 28, SOD and CAT activities were either not significantly different from the control or were higher, demonstrating a temporal multiphasic response of anti-oxidant enzymes. GST activity on day 28 was significantly reduced compared to controls. Acetylcholinesterase levels across the three-time points exhibited a complicated behaviour, with every exposure concentration being significantly different from the control. Chronic exposure negatively influences earthworm health status with elevated biomarker values analysed using IBRv2 index. This, in turn, impacted higher levels of hierarchical organization, significantly impairing reproduction and organismal homeostasis at the histological level and manifesting as decreasing cocoon formation and successful hatching events. Thus, the overall findings demonstrate that oxybenzone is toxic to Eisenia fetida at low-level, long-term exposure. Based on the concentration verification analysis and application of the EPA PestDF tool, oxybenzone undergoes single first-order kinetics degradation in OECD soil with DT50 and DT90 as 8.7-28.9 days, respectively.

Green synthesis of two-electron centre based ZnO/NiCo2S4 QDs-OVs using Punica granatum fruit peel extract for an exceptional visible light photocatalytic degradation of doxycycline and ciprofloxacin

Biosynthesis of nanomaterials using plant extract makes them attractive in the field of photocatalysis as they are environmental friendly. The current study focused on the biosynthesis of ZnO/NiCo₂S₄ QDs (NCs) using Punica granatum fruit peel extract as the reducing agent. The nanomaterials were characterized with XRD, FTIR, Raman, SEM, TEM, UV-vis DRS, BET, PL, EIS, and ESR analysis and were used for photocatalytic degradation of doxycycline (DOX) and ciprofloxacin (CIP). The bandgap of ZnO is 3.2 eV, and the decoration of NiCo₂S₄ QDs aids in narrowing the bandgap (2.8 eV), making the NCs visible light active. The fabricated NCs achieved 99 and 89% degradation of DOX and CIP respectively. The photocatalytic efficiency of ZnO/NiCo₂S₄ QDs was much higher compared to individual ZnO and NiCo₂S₄ QDs. The half-life period of DOX and CIP were evaluated to be 58 and 152 min respectively. The percentage of TOC removal in the photodegraded product of DOX and CIP was estimated to be 99 and 89% respectively, indicating the mineralization of the compounds. The enhanced photocatalytic efficiency of the NCs was attributed to the narrowed visible light active bandgap, synergistic charge transfer across the interface, and lower charge recombination. The intermediates formed during the photocatalytic degradation of DOX and CIP were analyzed using GC-MS/MS analysis, and the photodegradation pathway was elucidated. Also, the toxicity of the intermediates was computationally analyzed using ECOSAR software. The fabricated ZnO/NiCo₂S₄ QDs have excellent stability and reusability, confirmed by XRD and XPS analysis. The reusable efficiency of the NCs for the photocatalytic degradation of DOX and CIP were 98.93, and 99.4% respectively. Thus, the biologically fabricated NCs are shown to be an excellent photocatalyst and have wide applications in environmental remediation.

Improved Adsorption of Tetracycline in Water by a Modified Caulis spatholobi Residue Biochar

A potassium modified biochar (KBC) using Caulis spatholobi residue as the raw material was prepared by adopting a two-step method of pyrolysis followed by high-temperature potassium hydroxide activation, and its properties were characterized. Activation using potassium hydroxide under high temperature induced the loss of CaCO₃ and partial C on biochar, which created a high specific surface area (1336.31 m²/g) together with a developed pore structure. pH displayed a slight influence on tetracycline adsorption, which signified the slight influence of the existence of tetracycline and the charge potential of biochar. Besides, pore filling, hydrogen bonding and π-π EDA stacking interactions possibly resulted in tetracycline adsorption on biochar. Tetracycline adsorption was fast in the original period, followed by a slower rate of adsorption until equilibrium was reached. Adsorption kinetics of tetracycline could be described using secondary and Elovich kinetic models. Adsorption isotherms for tetracycline were well fitted to the Langmuir isotherm model, and the maximum adsorption capacity of KBC was 830.78 mg/g at 318 K. According to a study of the thermodynamics, the adsorption of tetracycline on KBC was an endothermic reaction process. Corresponding results in the present study demonstrated that high-temperature potassium hydroxide activation enabled biochar to effectively eliminate tetracycline from water and wastewater.

Ecofriendly and sustainable Sargassum spp.-based system for the removal of highly used drugs during the COVID-19 pandemic

Analgesic consumption increased significantly during the COVID-19 pandemic. A high concentration of this kind of drug is discarded in the urine, reaching the effluents of rivers, lakes, and seas. These medicines have brought serious problems for the flora and, especially, the ecosystems’ fauna. This paper presents the results of removing diclofenac, ibuprofen, and paracetamol in an aqueous solution, using Sargassum spp. from the Caribbean coast. The study consisted of mixing each drug in an aqueous solution with functionalized Sargassum spp in a container under constant agitation. Therefore, this work represents an alternative to solve two of the biggest problems in recent years; first, the reduction of the overpopulation of sargassum through its use for the remediation of the environment. Second is the removal of drug waste used excessively during the COVID-19 pandemic. Liquid samples of the solution were taken at intervals of 10 min and analyzed by fluorescence to determine the concentration of the drug.

The sorption capacity for diclofenac, ibuprofen, and paracetamol was 2.46, 2.08, and 1.41 μg/g, corresponding to 98 %, 84 %, and 54 % of removal, respectively. The removal of the three drugs was notably favored by increasing the temperature to 30 and 40 °C, reaching efficiencies close to 100 %. Moreover, the system maintains its effectiveness at various pH values. In addition, the Sargassum used can be reused for up to three cycles without reducing its removal capacity. The wide diversity of organic compounds favors the biosorption of drugs, removing them through various kinetic mechanisms. On the other hand, the Sargassum used in the drugs removal was analyzed by X-ray diffraction, FTIR spectroscopy, TGA analysis, and scanning electron microscopy before and after removal. The results showed an evident modification in the structure and morphology of the algae and demonstrated the presence of the biosorbed drugs. Therefore, this system is sustainable, simple, economical, environmentally friendly, highly efficient, and scalable at a domestic and industrial level that can be used for aquatic remediation environments.

Spent waste from edible mushrooms offers innovative strategies for the remediation of persistent organic micropollutants: A review

Urgent and innovative strategies for removal of persistent organic micropollutants (OMPs) in soil, groundwater, and surface water are the need of the hour. OMPs detected in contaminated soils and effluents from wastewater treatment plants (WWTPs) are categorized as environmentally persistent pharmaceutical pollutants (EPPPs), and endocrine disrupting chemicals (EDCs), their admixture could cause serious ecological issues to the non-target species. As complete eradication of OMPs is not possible with the extant conventional WWTPs technology, the inordinate and reckless application of OMPs negatively impacts environmental regenerative and resilience capacity. Therefore, the cardinal focus of this review is the bioremediation of persistent OMPs through efficient application of an agro-waste, i.e. spent mushroom waste (SMW). This innovative, green, long-term strategy embedded in the circular economy, based on state of the art information is comprehensively assessed in this paper. SMW accrues ligninolytic enzymes such as laccase and peroxidase, with efficient mechanism to facilitate biodegradation of recalcitrant organic pollutants. It is vital in this context that future research should address immobilization of such enzymes to overcome quantitative and qualitative issues obstructing their widespread use in biodegradation. Therefore, dual benefit is gained from cultivating critical cash crops like mushrooms to meet the escalating demand for food resources and to aid in biodegradation. Hence, mushroom cultivation has positive environmental, social, and economic implications in developing countries like India.

Development of a Citric-Acid-Modified Cellulose Adsorbent Derived from Moringa peregrina Leaf for Adsorptive Removal of Citalopram HBr in Aqueous Solutions

A citric-acid-modified Moringa peregrina leaf substrate was prepared and studied as an effective adsorbent for the adsorptive removal of citalopram HBr (CTM). FTIR spectra were utilized to characterize the prepared solid. The effects of experimental variables on the percentage removal of citalopram HBr were investigated using response surface methodology. The optimum conditions selected for removal of CTM were 7 and 4 min, 0.17 g per 50 mL and 35 mg·L⁻¹ for pH, contact time, adsorbent dose and initial concentration of CTM, respectively. Under the optimized experimental conditions, 82.59% CTM (35 mg·L⁻¹) was removed. The Langmuir isotherm, Freundlich isotherm, pseudo second-order kinetic model and diffusion-chemisorption model explained the adsorption data successfully. The maximum adsorption capacity at 298 K was 8.58 mg·g⁻¹. A thermodynamic study illustrated that CTM adsorption was spontaneous and endothermic in nature.

Emerging pharma residue contaminants: Occurrence, monitoring, risk and fate assessment - A challenge to water resource management

Water is one of the important gifts to mankind. In recent days the accessibility of pharmaceuticals in the environment is progressively a worldwide concern. The significant wellspring of these contaminations in water assets is drugs for human use or veterinary medications. Intermediates, active metabolites and raw materials present in water from pharmaceutical industry waste because of incomplete sewage treatment systems. Various pharmaceutical components such as analgesic/antipyretics such as Ibuprofen (57.9-104 ng/L), Diclofenac (17-129 ng/L), antibiotics such as Sulfamethoxazole (28.7-124.5 ng/L), Sulfamethazine (29.2-83.9 ng/L), Azithromycin (10-68 ng/L), psychiatric drug such as Carbamazepine (9.3-92.4 ng/L), stimulants such as caffeine greater than 55 ng/L, antidepressants, antihypertensive, contraceptives etc., are present in water resources and have been detected in mg/L to μg/L range. The synergic effects and ecotoxicological hazard assessment must be developed. Studies demonstrate that these drugs might cause morphological, metabolic and sex alterations on sea-going species, and interruption of biodegradation activities. Hazard analysis and assessments are in progress. However, the conventional effluent treatment methods are not sufficient to remove API (active pharmaceutical ingredients) from this water effectively. There is necessitate for continuous monitoring of the pharmaceutical compounds in aquatic ecosystem to save the environment and living form of lives from health hazards. This work highlights the hazards, environmental assessment and the mitigation measures of pharmaceutical pollutants.

Investigating a broad range of emerging contaminants in a set of anthropogenically impacted environmental compartments

Environmental compartments are repositories of probably thousands of emerging contaminants (ECs) released along with treated/untreated wastewater. Despite extensive studies on the detection of ECs in surface water, other environmental compartments such as sediments and groundwater are yet to be thoroughly investigated. To assess the heavy anthropogenic impact on the environment, 24 environmental samples comprising of surface water, sediment and groundwater collected from the Yamuna River basin of India were analyzed via target and suspect screening. The surface water and sediment samples were collected from upstream and downstream of densely populated cities and towns situated along the heavily contaminated river Yamuna. The groundwater samples were collected from shallow drinking water wells of the catchment. Liquid chromatography tandem mass-spectroscopy was used to quantify 10 widely consumed pharmaceuticals in the samples. The study also analyzed the potential health hazards posed by the quantified contaminants. In order to evaluate further, the surface water and groundwater samples were subjected to high resolution mass spectrometry (HRMS) screening against a library resulting in a list of 450 ECs in the surface water and 309 ECs in the groundwater. Agricultural chemicals and pharmaceuticals found abundantly in the samples and half of whom were reported first time. The risk quotient was calculated to assess the potential hazard of the target analytes.

Ecotoxicological Consequences of the Abatement of Contaminants of Emerging Concern by Ozonation—Does Mixture Complexity Matter?

Ozonation has been used to degrade persistent water contaminants, namely, pharmaceuticals and personal care products (PPCPs). However, ozonation can lead to by-products that can be more toxic than the parent compounds. This work aims to assess whether the ecotoxicological effects of ozonation are modified as the initial matrix being treated increases in complexity, considering mixtures of 2, 3, 4 and 5 PPCPs. The following PPCPs were used: two parabens (metylparaben (MP) and propylparaben (PP)), paracetamol (PCT), sulfamethoxazole (SMX) and carbamazepine (CBZ). The following model species were used to assess toxicity: the crustacean Daphnia magna, the microalgae Raphidocelis subcapitata, the macrophyte Lemna minor and the watercress Lepidium sativum. There was a trend of increased toxicity with increasing mixture complexity of the untreated samples, except for D. magna. The same was observed after ozonation with the exception of the mixture MP+PP, which showed high toxicity to all the tested species, namely 100% immobilization of D. magna. The toxicity of SMX to the primary producers decreased pronouncedly after ozonation, except for L. minor. This study highlights the importance of considering the complexity of the matrix being treated and of using an ecotoxicological test battery with a wide diversity of species for assessing ozonation efficiency.

Pharmaceutical Pollution in Aquatic Environments: A Concise Review of Environmental Impacts and Bioremediation Systems

The presence of emerging contaminants in the environment, such as pharmaceuticals, is a growing global concern. The excessive use of medication globally, together with the recalcitrance of pharmaceuticals in traditional wastewater treatment systems, has caused these compounds to present a severe environmental problem. In recent years, the increase in their availability, access and use of drugs has caused concentrations in water bodies to rise substantially. Considered as emerging contaminants, pharmaceuticals represent a challenge in the field of environmental remediation; therefore, alternative add-on systems for traditional wastewater treatment plants are continuously being developed to mitigate their impact and reduce their effects on the environment and human health. In this review, we describe the current status and impact of pharmaceutical compounds as emerging contaminants, focusing on their presence in water bodies, and analyzing the development of bioremediation systems, especially mycoremediation, for the removal of these pharmaceutical compounds with a special focus on fungal technologies.

Efficiency of the bank filtration technique for diclofenac removal: A review

Bank filtration (BF) has been employed for more than a century for the production of water with a better quality, and it has been showing satisfactory results in diclofenac attenuation. Considered the most administered analgesic in the world, diclofenac has been frequently detected in water bodies. Besides being persistent in the environment, this compound is not completely removed by the conventional water treatments, drinking water treatment plants (DWTPs) and wastewater treatment plant (WWTPs). BF has a high complexity, whose efficiency depends on the characteristics of the observed pollutant and on the environment where the system in installed, which is why this is a topic that has been constantly studied. Nevertheless, studies present the behavior of diclofenac during the BF process. In this context, this research performed the evaluation of the factors and the biogeochemical processes that influence the efficiency of the BF technique in diclofenac removal. The aerobic conditions, higher temperatures, microbial biomass density, hydrogen potential close to neutrality and sediments with heterogeneous fractions are considered the ideal conditions in the aquifer for diclofenac removal. Nonetheless, there is no consensus on which of these factors has the greatest contribution on the mechanism of attenuation during BF. Studies with columns in laboratory and modeling affirm that the highest degradation rates occur in the first centimeters (5-50 cm) of the passage of water through the porous medium, in the environment known as hyporheic zone, where intense biogeochemical activities occur. Research has shown 100% removal efficiency for diclofenac persistent to compounds not removed during the BF process. However, half of the studies had removal efficiency that ranged between 80 and 100%. Therefore, the performance of more in-depth studies on the degradation and mobility of this compound becomes necessary for a better understanding of the conditions and biogeochemical processes which act in its attenuation.

Catalytic and non-catalytic degradation of acetaminophen in supercritical water

Pharmaceutical industrial wastewater is typical wastewater consisting of complex organic compounds with higher concentration, microbial toxicity, strenuous to deteriorate, and environmental threatening. The present work assesses the degradation of recalcitrant acetaminophen (ACM) by a green technology known as supercritical water oxidation (SCWO). Experiments were carried out in a continuous flow SCWO reactor by altering reaction conditions such as temperature 400-600 °C, oxidant coefficient (OC 0 to 3), and Fe(II) catalyst concentration (0.5 and 1 mg L^-1) to study the technical feasibility of highly concentrated ACM. Liquid product analysis indicated the total organic carbon (TOC) removal efficiency could reach up to 99.5% without catalyst at 600 °C and 99.9% with Fe(II) at 500 °C. The addition of Fe not only suppressed the intermediate ring components but also promoted the formation of permanent gases via decarboxylation and reforming reactions. The reaction between Fe(II) and H₂O₂ in supercritical water is extremely fast, which has a direct impact on the system's operating conditions. The high activity exhibited by Fe(II) catalyst degraded the ACM completely at an operating condition of 500 °C. Maximum H₂ fraction was attained without catalyst at 600 °C, OC 0.5, and with the catalyst at 500 °C, respectively, whereas, CO₂ tends to rise significantly with both temperature and oxidant concentration. The catalytic process is efficient in comparison to the non-catalytic process. A possible reaction pathway was proposed based on the intermediates generated during the degradation.

Enhanced UV Direct Photolysis and UV/H2O2 for Oxidation of Triclosan and Ibuprofen in Synthetic Effluent: an Experimental Study

This study aimed to evaluate the implementation of an advanced oxidation system based on UV radiation and UV/H₂O₂ for degradation of TCS and IBU in synthetic effluent. The assays occurred in a 2-L reactor, protected from external light and equipped with a UV lamp (λ = 254 nm). The effect of contaminant concentration, fractions of chemical species present, and mineralization were evaluated. In the UV/ H₂O₂ system, different concentrations of H₂O₂ were studied for oxidation of the contaminants. The kinetic experiments took place between 75 and 270 min of UV irradiation. The results showed > 99% oxidation of TCS in the direct photolysis system at pH 9.4 after 12 min. The degradation of IBU in the UV/H₂O₂ system, when 10 mg L^-1 of H₂O₂ was used, was 97.39% oxidation. We obtained k' values of 0.189 min^-1 for TCS when its highest oxidation occurred and k' values of 0.0219 min^-1 for IBU. The system was not able to completely mineralize the contaminants, presenting high values of TOC and COD after treatment, thus suggesting the occurrence of phototransformation.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11270-022-05583-z.

Monsoon dilutes the concurrence but increases the correlation of viruses and Pharmaceuticals and Personal Care Products (PPCPs) in the urban waters of Guwahati, India: The context of pandemic viruses

Concurrence of pharmaceuticals and personal care products (PPCPs), pathogenic viruses, metals and microbial pollution along with their seasonal variations in the water environment are overarching in the context of existing pandemic, especially for tropical countries. The present study focuses on the seasonal influence on the vulnerability of urban water in Guwahati, the largest city in North-eastern India, through examining the concurrence of seven PPCPs, five viruses, faecal bacteria and nine metals in surface waters during monsoon (Summer-July 2017) and pre-monsoon (Winter-March 2018). Surface water sampling was carried out at different locations of the Brahmaputra River, its tributary Bharalu River (an unlined urban drain), and Dipor Bill Lake (Ramsar-recognized wetland). Both PPCPs and viruses were at high concentrations (e.g. up to 970 ng L^-1 caffeine, 2.5 × 10³ copies mL^-1 pepper mild mottle virus (PMMoV)) at the confluence points of urban drains and the river, while they were mostly undetectable at both upstream and downstream locations, implying strong self-purification ability of the river. All the analysed PPCPs and viruses were at much higher concentrations during pre-monsoon i.e., winter than during monsoon, implying heavy dilution and temperature effect during the monsoon. Overall, PPCPs and viruses were more correlated in monsoon but the risk quotient in the urban tributary was higher in pre-monsoon (e.g. 5061 in pre-monsoon and 1515 in monsoon for caffeine). PMMoV was found to be an excellent faecal pollution indicator due to its prevalence, detectability and specificity in all seasons. Overall, the seasonal fluctuations of the non-enveloped viruses monitored in this study is likely to be relevant for SARS-CoV-2. We contribute to address the literature scarcity pertaining to seasonal variations in the prevalence of viruses and their concurrences with contaminants of emerging concern.

High Concentrations of Pharmaceuticals in a Nigerian River Catchment

Pharmaceutical contamination of the environment is recognized as a global problem although most research has focused on Europe and North America to date, and there remains a dearth of information for developing countries, including those in Africa. To address this data gap, the occurrence of 37 pharmaceuticals belonging to 19 therapeutic classes was monitored in surface water and effluents in Lagos State, Southwest Nigeria. Samples were collected quarterly between April 2017 and March 2018 from 22 sites, and 26 compounds were detected at least once, many in the µg/L range. Maximum concentrations for those compounds detected ranged from 75 to 129 µg L^-1 , and even mean concentrations for 13 compounds were in the order of µg L^-1 . These values are among the highest ever measured globally. Sewage effluent was more important than drug manufacturing waste in polluting rivers, although there are likely to be numerous unregulated sources of effluent being discharged to rivers that require further study, including urban waste collection areas and vacuum trucks that collect effluent. Seasonal trends in the data were complex, with some compounds being found at higher concentrations in the dry season and, conversely, others being greater during the wet period; this variation potentially relates to the variety of pollution sources in the catchment. Pharmaceuticals are indispensable to human health, although their usage and discharge into the aquatic environment may lead to ecological problems and antibiotic resistance. The data we present indicate that pharmaceutical pollution of freshwaters is a serious issue in Nigeria, and management efforts are needed to improve this problem. Environ Toxicol Chem 2022;41:551-558. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Removal of tramadol from water using Typha angustifolia and Hordeum vulgare as biological models: Possible interaction with other pollutants in short-term uptake experiments

Tramadol (TRD) is widely detected in aquatic ecosystems as a result of massive abuse and insufficient removal from wastewater facilities. As a result, TRD can contaminate groundwater sources and/or agricultural soils. While TRD toxicity has been reported from aquatic biota, data about TRD detection in plants are scarce. Moreover, information regarding plant capability for TRD removal is lacking. To understand the fate of this opioid, we have investigated the uptake, translocation and removal capacity of TRD by plants, addressing short-term and long-term uptake. The uptake rates of TRD, in excised barley and cattail roots, were 5.18 and 5.79 μg g^-1 root fresh weight day^-1, respectively. However, TRD uptake was strongly inhibited after co-exposing these roots either with the drug venlafaxine (similar molecular structure as TRD) or with quinidine (an inhibitor of cellular organic cation transporters). When barley seedlings were exposed to TRD in a hydroponic experiment a removal efficiency up to 90% (within 15 days) was obtained, with bioconcentration and translocation factors close to 9 and 1, respectively. The combination of results from both plants and the inhibition observed after treatment with quinidine revealed that organic cation transporters may be involved in the uptake of TRD by plants.

Fe-N-C catalyst with Fe-NX sites anchored nano carboncubes derived from Fe-Zn-MOFs activate peroxymonosulfate for high-effective degradation of ciprofloxacin: Thermal activation and catalytic mechanism

Developing high-efficient catalysts is crucial for activating peroxymonosulfate (PMS). Fe-N-C catalysts exhibit excellent performance for PMS activation because of the contribution of doped N, Fe-Nx and Fe₃C sites. In our work, a series of Fe-N-C catalysts with high-performance was obtained by pyrolyzing Fe-Zn-MOFs precursors. During pyrolysis process, the change of chemical bonds and formation of active sites in the precursor were elucidated by characterization analysis and related catalytic experiments. Graphitic N, Fe-Nx and Fe₃C were confirmed to activate PMS synergistically for ciprofloxacin (CIP) degradation. Besides, the catalytic performance was proportional to the amount of doped iron and calcination temperature. Moreover, the Fe-N-C-3-800/PMS system not only displayed good recycling performance, but also had high anti-interference ability. Integrated with quenching and electron paramagnetic resonance (EPR) experiments, a non-radical pathway dominated by ¹O₂ was proposed. Furthermore, PMS could bond to Fe-N-C-3-800 to form intermediate for charge transfer, thus accelerate electron transfer between CIP and PMS to realize degradation of CIP. Six main pathways of CIP degradation were proposed, which include bond fission of N-C on piperazine ring and direct oxidation of CIP. This study provided a new idea for the design of heterogeneous carbon catalysts in advanced oxidation field.

Abundance, fate, and effects of pharmaceuticals and personal care products in aquatic environments

Pharmaceuticals and personal care products (PPCPs) are found in wastewater, and thus, the environment. In this study, current knowledge about the occurrence and fate of PPCPs in aquatic systems-including wastewater treatment plants (WWTPs) and natural waters around the world-is critically reviewed to inform the state of the science and highlight existing knowledge gaps. Excretion by humans is the primary route of PPCPs entry into municipal wastewater systems, but significant contributions also occur through emissions from hospitals, PPCPs manufacturers, and agriculture. Abundance of PPCPs in raw wastewater is influenced by several factors, including the population density and demography served by WWTPs, presence of hospitals and drugs manufacturers in the sewershed, disease burden of the population served, local regulations, and climatic conditions. Based on the data obtained from WWTPs, analgesics, antibiotics, and stimulants (e.g., caffeine) are the most abundant PPCPs in raw wastewater. In conventional WWTPs, most removal of PPCPs occurs during secondary treatment, and overall removal exceeds 90% for treatable PPCPs. Regardless, the total PPCP mass discharged with effluent by an average WWTP into receiving waters (7.35-20,160 g/day) is still considerable, because potential adverse effects of some PPCPs (such as ibuprofen) on aquatic organisms occur within measured concentrations found in surface waters.

Photocatalytic performance of 3D engineered chitosan hydrogels embedded with sulfur-doped C3N4/ZnO nanoparticles for Ciprofloxacin removal: Degradation and mechanistic pathways

Ciprofloxacin, a biotoxic micropollutant, is ubiquitously found in the water environment, which is a global concern. This study developed polymeric S-C3N4/ZnO-Chitosan (indexed as SCZ-CH) hydrogels for degrading Ciprofloxacin. The SCZ-CH hydrogels provided the Ciprofloxacin degradation efficiencies of ~93% and ~69% in UV and visible lights, respectively, at optimum conditions (SCZ-CH hydrogels with 2 g/L SCZ, 20 mg/L initial concentration, pH 5, and room temperature). In addition, immobilized SCZ-CH hydrogels structures enable easy separation of the SCZ catalyst from water. The spectroscopic and microscopic analyses of SCZ-CH hydrogels show multifaceted properties, like high oxygen concentrations, crystallinity, stacked structure, high roughness, and improved bandgap energy, which are responsible for the enhanced photocatalytic activity. The effects of water matrix and experimental conditions on Ciprofloxacin degradation were also studied, which suggested that the catalyst dose and solution pH have significant effects on photocatalytic activity. SCZ-CH hydrogels have shown good mineralization efficiency (~98%) and reusability (up to 10 cycles) for Ciprofloxacin removal. Superoxide radicals played an essential role in the degradation of Ciprofloxacin. The Ciprofloxacin molecules get degraded by driving radicals through oxidation, defluorination, substitution, and breaking of the rings. The proposed SCZ-CH hydrogels can be effectively used at a large scale to treat micropollutants.

Occurrence of Pharmaceutically Active Compounds and Potential Ecological Risks in Wastewater from Hospitals and Receiving Waters in Sri Lanka

The presence of pharmaceutically active compounds (PACs) in the environment and their associated hazards is a major global health concern; however, data on these compounds are scarce in developing nations. In the present study, the existence of 39 non-antimicrobial PACs and six of their metabolites in wastewater from hospitals and adjacent surface waters in Sri Lanka was investigated from 2016 to 2018. The highest amounts of the measured chemicals, including the highest concentrations of atorvastatin (14,620 ng/L) and two metabolites, mefenamic acid (12,120 ng/L) and o-desmethyl tramadol (8700 ng/L), were detected in wastewater from the largest facility. Mefenamic acid, gemfibrozil, losartan, cetirizine, carbamazepine, and phenytoin were detected in all the samples. The removal rates in wastewater treatment were 100% for zolpidem, norsertaline, quetiapine, chlorpromazine, and alprazolam. There was substantial variation in removal rates of PACs among facilities, and the overall data suggest that treatment processes in facilities were ineffective and that some PAC concentrations in the effluents were increased. The estimated risk quotients revealed that 14 PACs detected in water samples could pose low to high ecological risk to various aquatic organisms. Compounds such as ibuprofen, tramadol, and chlorpromazine detected in untreated and treated wastewater at these facilities pose a high risk to several aquatic organisms. Our study provides novel monitoring data for non-antimicrobial PAC abundance and the associated potential ecological risk related to hospitals and urban surface waters in Sri Lanka and further offers valuable information on pre-COVID-19 era PAC distribution in the country. Environ Toxicol Chem 2022;41:298-311. © 2021 SETAC.

Developmental toxicity assessment of 4-MBC in Danio rerio embryo-larval stages

Enormous production of cosmetic products and its indiscriminate use tends to discharge into the aquatic environment and might threaten non-target organisms inhabiting aquatic ecosystems. In the present study, developmental toxicity of 4-methylbenzylidene camphor (4-MBC), a widely used organic UV filter in personal care products has been evaluated using zebrafish embryo-larval stages. Waterborne exposure induced developmental toxicity and deduced 2.71 mg/L as 96 h LC₅₀ whereas embryos exposed to sub-lethal concentrations (50 and 500 μg/L) caused a significant delay in hatching rate, heart rate, reduced larval length, and restricted hatchlings motility besides the axial curvature. Chronic exposure to 10 dpf resulted in significant decrease in SOD activity at 500 μg/L with no changes in CAT level besides a significant increase in GST enzyme at 5 μg/L concentration in 5 dpf sampled larvae. However, all the three enzymes were significantly elevated in 10 dpf larvae indicating differential oxidative stress during the stages of development. Similar trend is noticed for acetylcholine esterase enzyme activity. A concentration dependent increase in malondialdehyde content was noted in larvae sampled at 5 and 10 dpf. In addition, multixenobiotic resistance (MXR) activity inhibition, and elevated oxidative tissue damage were noticed at 5 dpf with no significant changes in 10 dpf larvae. Furthermore, immunoblot analysis confirms 4-MBC induced apoptosis in zebrafish larvae with promoted cleaved Caspase-3, Bax and inhibited Bcl-2 proteins expression. Subsequently, docking studies revealed the binding potential of 4-MBC to zebrafish Abcb4 and CYP450 8A1 proteins with the binding energy of -8.1 and -8.5 kcal/mol representing target proteins interaction and toxicity potentiation. Our results showed that 4-MBC exposure triggers oxidative stress at sub-lethal concentrations leading to apoptosis, deformities and locomotion perturbations in developing zebrafish.This is first of its kind in systematically demonstrating developmental toxicity of 4-MBC and the information shall be used for aquatic toxicity risk assessment.

Psychoactive drugs citalopram and mirtazapine caused oxidative stress and damage of feeding behavior in Daphnia magna

As the emerging contaminants, the environmental risks of drug-derived pollutants have attracted extensive attention. Citalopram (CTP) and mirtazapine (MTP) are commonly used as modern antidepressant drugs. Previous studies had proved that CTP and MTP entered the aquatic environment, but less reported the negative effects of the drugs on aquatic organisms. Herein, the effects on the feeding rate of Daphnia magna (D. magna) induced by psychotropic drugs CTP and MTP were investigated, which the possible mechanisms were analyzed with the oxidative stress and damage. Generally, the feeding rates of exposed D. magna under all concentrations of CTP and 1.03 mg/L of MTP were significantly decreased after exposure (p < 0.05 or p < 0.01). The inhibitory effect of CTP on the feeding rate of D. magna was time- and dose-dependent. The levels of reactive oxygen species (ROS) were particularly increased in D. magna after CTP and MTP exposure (p < 0.05 or p < 0.01). The level of antioxidant molecules glutathione S-transferase (GST) and the activity of scavenging enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) of D. magna were increased (p < 0.05 or p < 0.01). In consequence, the levels of malondialdehyde (MDA), protein carbonyl, and 8-hydroxydeoxyguanosine (8-OHdG) were increased (p < 0.05 or p < 0.01), which indicated oxidative damage caused by MTP and CTP, due to the imbalance of antioxidative stress system. These findings indicated that psychoactive drugs posed a high toxic threat to the aquatic organisms, and the aquatic environmental risks caused by using psychoactive drugs deserve more attention.

Occurrence, transformation, bioaccumulation, risk and analysis of pharmaceutical and personal care products from wastewater: a review

Almost all aspects of society from food security to disease control and prevention have benefited from pharmaceutical and personal care products, yet these products are a major source of contamination that ends up in wastewater and ecosystems. This issue has been sharply accentuated during the coronavirus disease pandemic 2019 (COVID-19) due to the higher use of disinfectants and other products. Here we review pharmaceutical and personal care products with focus on their occurrence in the environment, detection, risk, and removal.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10311-022-01498-7.

Treatment technologies to mitigate the harmful effects of recalcitrant fluoroquinolone antibiotics on the environ- ment and human health

Antibiotic proliferation in the environment and their persistent nature is an issue of global concern as they induce antibiotic resistance threatening both human health and the ecosystem. Antibiotics have therefore been categorized as emerging pollutants. Fluoroquinolone (FQs) antibiotics are an emerging class of contaminants that are used extensively in human and veterinary medicine. The recalcitrant nature of fluoroquinolones has led to their presence in wastewater, effluents and water bodies. Even at a low concentration, FQs can stimulate antibacterial resistance. The main sources of FQ contamination include waste from pharmaceutical manufacturing industries, hospitals and households that ultimately reaches the wastewater treatment plants (WWTPs). The conventional WWTPs are unable to completely remove FQs due to their chemical stability. Therefore, the development and implementation of more efficient, economical, convenient treatment and removal technologies are needed to adequately address the issue. This review provides an overview of the technologies available for the removal of fluoroquinolone antibiotics from wastewater including adsorptive removal, advanced oxidation processes, removal using non-carbon based nanomaterials, microbial degradation and enzymatic degradation. Each treatment technology is discussed on its merits and limitations and a comparative view is presented on the choice of an advanced treatment process for future studies and implementation. A discussion on the commercialization potential and eco-friendliness of each technology is also included in the review. The importance of metabolite identification and their residual toxicity determination has been emphasized. The last section of the review provides an overview of the policy interventions and regulatory frameworks that aid in retrofitting antibiotics as a central key focus contaminant and thereby defining the discharge limits for antibiotics and establishing safe manufacturing practices.

Heterogeneous Photocatalysis of Metronidazole in Aquatic Samples

Metronidazole (MET) is a commonly detected contaminant in the environment. The compound is classified as poorly biodegradable and highly soluble in water. Heterogeneous photocatalysis is the most promoted water purification method due to the possibility of using sunlight and small amounts of a catalyst needed for the process. The aim of this study was to select conditions for photocatalytic removal of metronidazole from aquatic samples. The effect of catalyst type, mass, and irradiance intensity on the efficiency of metronidazole removal was determined. For this purpose, TiO₂, ZnO, ZrO₂, WO₃, PbS, and their mixtures in a mass ratio of 1:1 were used. In this study, the transformation products formed were identified, and the mineralization degree of compound was determined. The efficiency of metronidazole removal depending on the type of catalyst was in the range of 50-95%. The highest MET conversion (95%) combined with a high degree of mineralization (70.3%) was obtained by using a mixture of 12.5 g TiO₂-P25 + PbS (1:1; v/v) and running the process for 60 min at an irradiance of 1000 W m^-2. Four MET degradation products were identified by untargeted analysis, formed by the rearrangement of the metronidazole and the C-C bond breaking.

Simultaneous adsorptive removal of conventional and emerging contaminants in multi-component systems for wastewater remediation: A critical review

The rapid growth of population and industrialization results in pollution of freshwater sources which leads to the water stress conditions on the world in future. Adsorption is a low cost and popular technique for the removal of contaminants from water bodies. Most of the reports till date are on removal of a single component from aqueous solutions using this technique, but the real-world effluent contains multiple contaminants such as dyes, heavy metals, pesticides, antibiotics and many more. Therefore, a study on simultaneous removal of contaminants is highly needed to obtain a suitable adsorbent that can be used commercially. This critical review provides a detailed study on the removal of contaminants in the presence of other contaminant/s i.e., from a multi-component system (MCS). The different possible interaction mechanisms in MCS like synergism, antagonism and non-interaction are discussed. The MCS containing the mixture of conventional contaminants such as heavy metals and dyes, and other emerging contaminants such as antibiotics, organic contaminants, pesticides and personal care products are explained in depth. This review article will be helpful for researchers working in the field of simultaneous removal of contaminants from MCSs for wastewater remediation.

O/N/P-doped biochar induced to enhance adsorption of sulfonamide with coexisting Cu2+/ Cr (VI) by air pre-oxidation

The aim of this work to study the effectiveness of newly synthesized O/N/P-doped biochar for the removal of antibiotics with coexisting heavy metals. This study developed a low-dose additive agent with air pre-oxidation (APO) to obtain O/N/P-doped biochar (ONPBC) at 650/350 °C pyrolysis temperature with adsorption amount of 76.99 mg·g^-1 (ONPBC650) and 62.33 mg·g^-1 (ONPBC350) for sulfapyridine (SPY), comparing to pristine biochar 9.25 mg·g^-1 (BC650) and 11.60 mg·g^-1 (BC350), indicating the adsorption capacity of biochar has been greatly improved after modification. The main sorption mechanisms were elucidated for ONPBC650 (surface physical sorption) and ONPBC350 (H-bonding). The coexisting Cu²⁺/Cr (VI) showed different inhibition effects on the adsorption of SPY by ONPBC650/350. Considering a trade-off between high adsorption capacity and low inhibition effect of coexisting heavy metals, economic low-temperature O/N/P-doped biochar such as ONPBC350 could be a preferred adsorbent for the removal of sulfonamide or similar organic pollutants from contaminated water.

Occurrence of Pharmaceuticals and Endocrine Disrupting Compounds in Brazilian Water and the Risks They May Represent to Human Health

The risks of pharmaceuticals and endocrine disrupting compounds (P&EDC) to the environment and human health are a current topic of interest. Hundreds of P&EDC may reach the environment, hence, there is a need to rank the level of concern of human exposure to these compounds. Thus, this work aimed at setting a priority list of P&EDC in Brazil, by studying their occurrence in raw and drinking water, calculating health guideline values (GV), and estimating the risks of population exposure to water intake. Data on the Brazilian pharmaceutical market as well as published data of the monitoring of Brazilian natural and drinking water have been collected by means of an exhaustive literature review. Furthermore, many foreign data were also collected to enable a comparison of the values found in Brazilian studies. A list of 55 P&EDC that have the potential to be found in Brazilian water is proposed, and for 41 of these a risk assessment was performed by estimating their margin of exposure (ME), by considering their occurrence in drinking water, and guideline values estimated from reported acceptable daily intake (ADI) data. For seven compounds the risk was deemed high (three estrogens and four anti-inflammatories), whereas for another seven compounds, it was regarded as an 'alert' situation. Although such risk analysis is conservative, since it has been calculated based on the highest reported P&EDC concentration in drinking water, it highlights the need to enhance their monitoring in Brazil to strengthen the database and support decision makers. An analysis of the occurrence of antimicrobial resistance agents (antibiotics, resistant bacteria, and resistance genes) in surface waters was also carried out and confirmed that such agents are present in water sources throughout Brazil, which deserves the attention of policy makers and health agents to prevent dissemination of antimicrobial resistance through water use.

Pharmaceuticals and personal care products' (PPCPs) impact on enriched nitrifying cultures

The impact of pharmaceutical and personal care products (PPCPs) on the performance of biological wastewater treatment plants (WWTPs) has been widely studied using whole-community approaches. These contaminants affect the capacity of microbial communities to transform nutrients; however, most have neither honed their examination on the nitrifying communities directly nor considered the impact on individual populations. In this study, six PPCPs commonly found in WWTPs, including a stimulant (caffeine), an antimicrobial agent (triclosan), an insect repellent ingredient (N,N-diethyl-m-toluamide (DEET)) and antibiotics (ampicillin, colistin and ofloxacin), were selected to assess their short-term toxic effect on enriched nitrifying cultures: Nitrosomonas sp. and Nitrobacter sp. The results showed that triclosan exhibited the greatest inhibition on nitrification with EC₅₀ of 89.1 μg L^-1. From the selected antibiotics, colistin significantly affected the overall nitrification with the lowest EC₅₀ of 1 mg L^-1, and a more pronounced inhibitory effect on ammonia-oxidizing bacteria (AOB) compared to nitrite-oxidizing bacteria (NOB). The EC₅₀ of ampicillin and ofloxacin was 23.7 and 12.7 mg L^-1, respectively. Additionally, experimental data suggested that nitrifying bacteria were insensitive to the presence of caffeine. In the case of DEET, moderate inhibition of nitrification (<40%) was observed at 10 mg L^-1. These findings contribute to the understanding of the response of nitrifying communities in presence of PPCPs, which play an essential role in biological nitrification in WWTPs. Knowing specific community responses helps develop mitigation measures to improve system resilience.

Pharmaceuticals, pesticides and metals/metalloids in Lake Guaíba in Southern Brazil: Spatial and temporal evaluation and a chemometrics approach

Compiling and reporting data related to the presence of pharmaceuticals and pesticides are crucial means of assessing the risk those chemicals pose to human health and environment. Data sets from different sources were combined using a data fusion approach to produce a spatial and temporal variation of contaminants presents in water from Lake Guaíba (29°55'-30°24' S; 51°01'-51°20' W). Lake Guaíba is a 496 km² water body situated in the geological depression of Rio Grande do Sul State, Brazil; that is fed by several rivers from the metropolitan area, the 5th largest metro area in Brazil, with approximately 5 million inhabitants. Analytical methodology to quantify pharmaceuticals and pesticides by LC-QTOF-MS and GC-MS/MS was validated for 41 pharmaceutical and 62 pesticides. Furthermore, 27 chemical elements were analyzed by ICP-MS, and physical chemical parameters were determined using established methodologies. All validation parameters were in accordance with the National Institute of Metrology, Standardization, and Industrial Quality. Thirty-five water samples were analyzed from January to August 2019, and 15 pharmaceuticals and 25 pesticides were present in concentrations ranging from 6.00 ng L^-1 to 580.00 ng L^-1. Twenty-seven elements were analyzed during the same period, and 18 were present in concentrations ranging from 0.2 μg L^-1 to 7060 μg L^-1. Samples were tagged according to the points and months of collection to identify temporal and spatial patterns. The main findings show that the compounds are distributed throughout the studied area without an apparent regular pattern, suggesting that events in a specific point affect the entire ecosystem. Conversely, temporal variations were well defined, as samples were grouped according to the climatic conditions of the months of collection. Considering the calculated quotient risks, atrazine, cyproconazole, diuron, and simazine showed the highest risk levels for algae; acetaminophen, diclofenac, and ibuprofen showed the highest risk levels for aquatics invertebrates.

A Review on the Removal of Carbamazepine from Aqueous Solution by Using Activated Carbon and Biochar

Carbamazepine (CBZ), one of the most used pharmaceuticals worldwide and a Contaminant of Emerging Concern, represents a potential risk for the environment and human health. Wastewater treatment plants (WWTPs) are a significant source of CBZ to the environment, polluting the whole water cycle. In this review, the CBZ presence and fate in the urban water cycle are addressed, with a focus on adsorption as a possible solution for its removal. Specifically, the scientific literature on CBZ removal by activated carbon and its possible substitute Biochar, is comprehensively scanned and summed up, in view of increasing the circularity in water treatments. CBZ adsorption onto activated carbon and biochar is analyzed considering several aspects, such as physicochemical characteristics of the adsorbents, operational conditions of the adsorption processes and adsorption kinetics and isotherms models. WWTPs usually show almost no removal of CBZ (even negative), whereas removal is witnessed in drinking water treatment plants through advanced treatments (even >90%). Among these, adsorption is considered one of the preferable methods, being economical and easier to operate. Adsorption capacity of CBZ is influenced by the characteristics of the adsorbent precursors, pyrolysis temperature and modification or activation processes. Among operational conditions, pH shows low influence on the process, as CBZ has no charge in most pH ranges. Differently, increasing temperature and rotational speed favor the adsorption of CBZ. The presence of other micro-contaminants and organic matter decreases the CBZ adsorption due to competition effects. These results, however, concern mainly laboratory-scale studies, hence, full-scale investigations are recommended to take into account the complexity of the real conditions.

Ciprofloxacin and acetaminophen sorption onto banana peel biochars: Environmental and process parameter influences

Environmental (pH, temperature ionic strength, cations, anions) and process (pyrolysis temperature, particle size, adsorbent dosage, initial concentration) parameters were evaluated for ciprofloxacin and acetaminophen sorption onto a series of sustainable banana peel biochars. Ciprofloxacin and acetaminophen were chosen as model pharmaceuticals for removal owing to their worldwide presence in aquatic systems. After pyrolytic preparation from 450 to 750 °C, the biochars were qualitatively and quantitatively characterized by physicochemical, morphological, mineralogical and elemental analyses. Batch sorption studies were employed to evaluate the pH effects from 2 to 10, biochar pyrolysis temperatures (450, 550, 650, and 750 °C), particle sizes (30-50, 50-100, 100-150 BSS mesh), adsorbent dosages (0.5, 1.0, 2.0 g/L), adsorbate concentrations (0.5-200 ppm) and uptake temperatures (10, 25, 40 °C) on sorption efficiency. Maximum pharmaceutical sorption is achieved by the biochar prepared at 750 °C. Sorption rate increased with decrease in biochar particle size from 30 to 50 to 100-150 BSS mesh. Relationships between biochar properties and their sorptive potential showed positive correlations with surface area, total pore volume, %C, %ash and C/N molar ratios. Sorption data was modelled using different isotherm models and both kinetic and thermodynamic equations. Maximum Langmuir capacities of ciprofloxacin and acetaminophen on BPBC750 were 23.3 and 40.8 mg/g at 10 °C; 21.0 and 49.93 mg/g at 25 °C and 20.42 and 57.3 mg/g at 45 °C, respectively. Langmuir isotherm fittings and thermodynamic parameters confirmed the exothermic sorption (for ciprofloxacin) and endothermic sorption (for acetaminophen). The role of ionic strength, cations and anions on pharmaceuticals sorption were evaluated. H-bonding, π-π-interactions and pore diffusion were major contributors to pharmaceutical sorption.

Determination of pharmaceuticals and heavy metals in groundwater for human and animal consumption and crop irrigation in Galicia

Pharmaceuticals and heavy metals are contaminants present in groundwaters, which are the main source of drinking water in most parts of the world. In the northwest region of Spain, Galicia, groundwater harvesting is a common practice for drinking water supply, crop irrigation, cattle watering, as well as recreational use such as filling pools. In order to assess the quality of Galician groundwaters, the presence of 21 pharmaceuticals and 10 heavy metals was analysed by UPLC-MS/MS and ICP/MS methods, respectively, in a total of 118 groundwater samples from private wells. Seventeen of the 21 compounds studied were detected in 28% of the samples, with the highest presence of pharmaceuticals belonging to the antimicrobial group (52%), specifically the sulphonamides group in a range of concentration between 21 and 14.9 ng/L. In addition, 30% of the samples contained at least one heavy metal (Mn, As and Fe) above the legally permitted levels. Evaluation of the risk associated with the consumption of the analysed groundwater indicated no human risk for any of the detected pharmaceuticals but high cancer risk for children due to Cd, Cr and As concentrations was observe.

A Review on the Application of Zeolites and Mesoporous Silica Materials in the Removal of Non-Steroidal Anti-Inflammatory Drugs and Antibiotics from Water

Zeolites and mesoporous silica materials are effective adsorbents that can be useful for the removal of various pharmaceuticals including non-steroidal anti-inflammatory drugs and antibiotics from low-quality water. This paper summarizes the properties and basic characteristics of zeolites and mesoporous silica materials and reviews the recent studies on the efficacy of the adsorption of selected non-steroidal medicinal products and antibiotics by these adsorbents to assess the potential opportunities and challenges of using them in water treatment. It was found that the adsorption capacity of sorbents with high silica content is related to their surface hydrophobicity (hydrophilicity) and structural features, such as micropore volume and pore size, as well as the properties of the studied medicinal products. This review can be of help to scientists to develop an effective strategy for reducing the amount of these two groups of pharmaceuticals in wastewater.

The association between antimicrobials and the antimicrobial-resistant phenotypes and resistance genes of Escherichia coli isolated from hospital wastewaters and adjacent surface waters in Sri Lanka

The presence of antimicrobials, antimicrobial-resistant bacteria (ARB), and the associated antimicrobial resistance genes (ARGs) in the environment is a global health concern. In this study, the concentrations of 25 antimicrobials, the resistance of Escherichia coli (E. coli) strains in response to the selection pressure imposed by 15 antimicrobials, and enrichment of 20 ARGs in E. coli isolated from hospital wastewaters and surface waters were investigated from 2016 to 2018. In hospital wastewaters, clarithromycin was detected at the highest concentration followed by sulfamethoxazole and sulfapyridine. Approximately 80% of the E. coli isolates were resistant, while 14% of the isolates exhibited intermediate resistance against the tested antimicrobial agents. Approximately 61% of the examined isolates were categorized as multidrug-resistant bacteria. The overall abundance of phenotypes that were resistant toward drugs was in the following order: β-lactams, tetracycline, quinolones, sulfamethoxazole/trimethoprim, aminoglycosides, and chloramphenicol. The data showed that the E. coli isolates frequently harbored bla_TEM, bla_CTX-M, tetA, qnrS, and sul2. These results indicated that personal care products were significantly associated with the presence of several resistant phenotypes and resistance genes, implying their role in co-association with multidrug resistance. Statistical analysis also indicated a disparity specific to the site, treatment, and year in the data describing the prevalence of ARB and ARGs and their release into downstream waters. This study provides novel insights into the abundance of antimicrobial, ARB and ARGs in Sri Lanka, and could further offer invaluable information that can be integrated into global antimicrobial resistance databases.