Occurrence and ecotoxicological assessment of pharmaceuticals: Is there a risk for the Mediterranean aquatic environment?

Application of fungal-based microbial fuel cells for biodegradation of pharmaceuticals: Comparative study of individual vs. mixed contaminant solutions

The present study focuses on the application of fungal-based microbial fuel cells (FMFC) for the degradation of organic pollutants including Acetaminophen (APAP), Para-aminophenol (PAP), Sulfanilamide (SFA), and finally Methylene Blue (MB). The objective is to investigate the patterns of degradation (both individually and as a mixture solution) of the four compounds in response to fungal metabolic processes, with an emphasis on evaluating the possibility of generating energy. Linear Sweep Voltammetry (LSV) has been used for electrochemical analysis of the targeted compounds on a Glassy Carbon Electrode (GCE). A dual chamber MFC has been applied wherein the cathodic compartment, the reduction reaction of oxygen was catalyzed by an elaborated biofilm of Trametes trogii, and the anodic chamber consists of a mixed solution of 200 mg L-1 APAP, PAP, MB, and SFA in 0.1 M PBS and an elaborated biofilm of Trichoderma harzianum. The obtained results showed that all the tested molecules were degraded over time by the Trichoderma harzianum. The biodegradation kinetics of all the tested molecules were found to be in the pseudo-first-order. The results of half-lives and the degradation rate reveal that APAP in its individual form degrades relatively slower (0.0213 h-1) and has a half-life of 33 h compared to its degradation in a mixed solution with a half-life of 20 h. SFA showed the longest half-life in the mixed condition (98 h) which is the opposite of its degradation as individual molecules (20 h) as the fastest molecule compared to other pollutants. The maximum power density of the developed MFC dropped from 0.65 mW m-2 to 0.32 mW m-2 after 45.5 h, showing that the decrease of the residual concentration of molecules in the anodic compartment leads to the decrease of the MFC performance.

A newly NH2-UiO-66 composite functionalized by molecularly imprinted polymer for selective and rapid removal of sulfamethoxazole

Metal-organic frameworks (MOFs) are used as novel adsorption materials owing to their large surface area and tunable pore size. However, the lack of selectivity considerably limits their application. Consequently, designing functionalized MOFs with specific recognition abilities is essential for enhancing their adsorption performance. Herein, we synthesized a functionalized NH2-UiO-66 composite modified by molecularly imprinted polymers (MIP@NH2-UiO-66) via a one-step polymerization process in which NH2-UiO-66 and MIP were formed simultaneously. Results demonstrate that MIP@NH2-UiO-66 effectively recognized sulfamethoxazole (SMX) in complex matrices. The adsorption equilibrium was reached in only 30 min, and this fast SMX adsorption on MIP@NH2-UiO-66 was described by the Avrami kinetic model, which indicates a spontaneous and exothermic adsorption process. Within the pH range of 3.0-10.0, MIP@NH2-UiO-66 exhibited an optimal binding capacity for SMX, and the maximum adsorption of SMX was 68.36 mg g-1 at 25°C, which exceeded those of existing adsorption materials (< 60.10 mg g-1). Additionally, MIP@NH2-UiO-66 was regenerated for ∼17 cycles compared to less than eight cycles for the other adsorbents. MIP@NH2-UiO-66 effectively removed 90.58%-99.60% of SMX from river water, rainwater, soil, sediment, chicken, pork, and milk samples, with a relative standard deviation of less than 4.43%. The superior adsorption of SMX on MIP@NH2-UiO-66 was primarily driven by the synergistic effects of the imprinting sites, hydrogen bonding, and electrostatic forces. The one-step polymerization method substantially simplified the synthesis process and reduced the costs, which are promising factors for the synthesis of MOFs with high selectivity.

Anthropogenic activities drive the distribution and ecological risk of antibiotics in a highly urbanized river basin

Although antibiotics are widely detected in river water, their quantitative relationships with influencing factors in rivers remain largely unexplored. Here, 15 widely used antibiotics were comprehensively analyzed in the Dongjiang River of the Pearl River system. The total antibiotic concentration in river water ranged from 13.84 to 475.04 ng/L, with fluoroquinolones increasing from 11 % in the upstream to 38 % in the downstream. The total antibiotic concentration was high downstream and significantly correlated with the spatial distribution of population density, animal production, and land-use type. The total risk quotient of antibiotics for algae was higher than that for crustaceans and fish. Based on the optimized risk quotient method, amoxicillin, ofloxacin, and norfloxacin were identified as priority antibiotics. The key predictors of antibiotic levels were screened through Mantel test, correlation analysis, and multiple regression models. Water physicochemical parameters significantly impacted antibiotics and could be used as easy-to-measure surrogates associated with elevated antibiotics. Cropland negatively affected fluoroquinolones and sulfonamides, whereas urban land exerted positive impacts on fluoroquinolones, β-lactam, and sulfonamides. In the main stream, population, animal production, urbanization status, and economic development had key effects on the distribution of florfenicol, norfloxacin, ofloxacin, and sulfadiazine.

Occurrence, removal, and prioritization of organic micropollutants in four full-scale wastewater treatment plants in Korea

This study investigated the occurrence, removal rate, and potential risks of 43 organic micropollutants (OMPs) in four municipal wastewater treatment plants (WWTPs) in Korea. Results from two-year intensive monitoring confirmed the presence of various OMPs in the influents, including pharmaceuticals such as acetaminophen (pain relief), caffeine (stimulants), cimetidine (H2-blockers), ibuprofen (non-steroidal anti-inflammatory drugs- NSAIDs), metformin (antidiabetics), and naproxen (NSAIDs) with median concentrations of >1 μg/L. Some pharmaceuticals (carbamazepine-anticonvulsants, diclofenac-NSAIDs, propranolol-β-blockers), corrosion inhibitors (1H-benzotriazole-BTR, 4-methyl-1H-benzotriazole-4-TTR), and perfluorinated compounds (PFCs) were negligibly removed during WWTP treatment. The OMP concentrations in the influents and effluents were mostly lower in August than those of other months (p-value <0.05) possibly due to wastewater dilution by high precipitation or enhanced biodegradation under high-temperature conditions. The anaerobic-anoxic-oxic process (A2O) with a membrane bioreactor exhibited higher OMP removal than other processes, such as A2O with sedimentation or the conventional activated sludge process (p-value <0.05). Pesticides (DEET and atrazine), corrosion inhibitors (4-TTR and BTR), and metformin were selected as priority OMPs in toxicity-driven prioritization, whereas PFCs were determined as priority OMPs given their persistence and bioaccumulation properties. Overall, our results contribute to an important database on the occurrence, removal, and potential risks of OMPs in Korean WWTPs.

Application of in vitro bioassays to monitor pharmaceuticals in water: A synthesis of chronological analysis, mode of action, and practical insights

Pharmaceutical compounds in wastewater have emerged as a significant concern for the aquatic environment. The use of in vitro bioassays represents a sustainable and cost-effective approach for assessing the potential toxicological risks of these biologically active compounds in wastewater and aligns with ethical considerations in research. It facilitates high-throughput analysis, captures mixture effects, integrates impacts of both known and unknown chemicals, and reduces reliance on animal testing. The core aim of the current review was to explore the practical application of in vitro bioassays in evaluating the environmental impacts of pharmaceuticals in wastewater. This comprehensive review strives to achieve several key objectives. First, it provides a summary categorisation of pharmaceuticals based on their mode of action, providing a structured framework for understanding their ecological significance. Second, a chronological analysis of pharmaceutical research aims to document their prevalence and trends over time, shedding light on evolving environmental challenges. Third, the review critically analyses existing bioassay applications in wastewater, while also examining bioassay coverage of representative compounds within major pharmaceutical classes. Finally, it explores the potential for developing innovative bioassays tailored for water quality monitoring of pharmaceuticals, paving the way for more robust environmental monitoring and risk assessment. Overall, adopting effect-based methods for pharmaceutical monitoring in water holds significant promise. It encompasses a broad spectrum of biological impacts, promotes standardized protocols, and supports a bioassay test battery approach indicative of different endpoints, thereby enhancing the effectiveness of environmental risk assessment.

Public awareness, knowledge, and attitude regarding proper disposal of unused medicines and associated factors in Gondar city, northwest Ethiopia

Background

Proper disposal of unwanted medicines, in addition to reducing wastage, has a positive impact on the environment and public health. Improper disposal of medications increases the risk of accidental poisonings, particularly among children. This study aimed to assess the level of knowledge, attitudes, and awareness regarding the proper disposal of unused medicines in Gondar city, northwest Ethiopia.

Method

From 30 July to 30 August 2023, a community-based cross-sectional study was conducted among the public in Gondar city. The data were gathered using the Kobo toolbox, exported into an Excel sheet, and then analyzed using SPSS version 27. Multivariate and bivariate binary logistic regressions were performed. A p-value of 0.05 with a 95% confidence interval (CI) was used to determine statistical significance.

Result

From 786 study participants, the overall knowledge and attitude of the community toward the proper disposal of unused medicines were 42.6 and 42.9%, respectively. Factors identified in this study included ages between 19 and 25 [AOR = 6.91, 95% CI: (3.45, 13.84); education level: secondary [AOR = 11.82, 95% CI: (1.01, 3.29)] and college and above [AOR = 5.68, 95% CI: (2.25, 14.30)]; prior information [AOR = 6.41; 95% CI: (4.02, 10.22)]; and good attitudes [AOR = 2.11; 95% CI: (1.47, 3.02)]] as factors associated with good knowledge toward proper disposal of unused medicines. In addition, receiving information [AOR = 1.86 95% CI: (1.22, 2.86)], taking medication in the past 6 months [AOR = 1.61, 95% CI: (1.09, 2.38)], and being knowledgeable [AOR = 2.07 95% CI: (1.46, 2.94)] were factors contributing to positive attitudes toward the disposal of unused medicines among the general public. Furthermore, approximately 369 participants (46.9%) in our study lacked awareness about the harmful effects of disposing of unused medicine in regular waste.

Conclusion

A relatively low level of knowledge and attitudes about the proper disposal of unused medications is present in the community. In this regard, a well-coordinated and methodical public awareness campaign is recommended to disseminate information and promote the appropriate disposal of unused medications.

A Pretty Kettle of Fish: A Review on the Current Challenges in Mediterranean Teleost Reproduction

The Mediterranean region is facing several environmental changes and pollution issues. Teleosts are particularly sensitive to these challenges due to their intricate reproductive biology and reliance on specific environmental cues for successful reproduction. Wild populations struggle with the triad of climate change, environmental contamination, and overfishing, which can deeply affect reproductive success and population dynamics. In farmed species, abiotic factors affecting reproduction are easier to control, whereas finding alternatives to conventional diets for farmed teleosts is crucial for enhancing broodstock health, reproductive success, and the sustainability of the aquaculture sector. Addressing these challenges involves ongoing research into formulating specialized diets, optimizing feeding strategies, and developing alternative and sustainable feed ingredients. To achieve a deeper comprehension of these challenges, studies employing model species have emerged as pivotal tools. These models offer advantages in understanding reproductive mechanisms due to their well-defined physiology, genetic tractability, and ease of manipulation. Yet, while providing invaluable insights, their applicability to diverse species remains constrained by inherent variations across taxa and oversimplification of complex environmental interactions, thus limiting the extrapolation of the scientific findings. Bridging these gaps necessitates multidisciplinary approaches, emphasizing conservation efforts for wild species and tailored nutritional strategies for aquaculture, thereby fostering sustainable teleost reproduction in the Mediterranean.

Application of catalytic ozonation using Y zeolite in the elimination of pharmaceuticals in effluents from municipal wastewater treatment plants

Catalytic ozonation using faujasite-type Y zeolite with two different SiO2/Al2O3 molar ratios (60 and 12) was evaluated for the first time in the removal of 25 pharmaceutical compounds (PhCs) present in real effluents from two municipal wastewater treatment plants both located in the Mediterranean coast of Spain. Additionally, control experiments including adsorption and direct ozonation, were conducted to better understand the fundamental aspects of the different individual systems in wastewater samples. Commercial zeolites were used in sodium form (NaY). The results showed that the simultaneous use of ozone and NaY zeolites significantly improved the micropollutants degradation rate, able to degrade 95 % of the total mixture of PhCs within the early 9 min using the zeolite NaY-12 (24.4 mg O3 L-1 consumed), while 12 min of reaction with the zeolite NaY-60 (31 mg O3 L-1 consumed). In the case of individual experiments, ozonation removed 95 % of the total mixture of PhCs after 25 min (46.2 mg O3 L-1 consumed), while the direct adsorption, after 60 min of contact time, eliminated 30 % and 44 % using the NaY-12 and NaY-60 zeolites, respectively. Results showed that the Brønsted acid sites seemed to play an important role in the effectiveness of the treatment with ozone. Finally, the environmental assessment showed that the total risk quotients of pharmaceuticals were reduced between 87 %-99 % after ozonation in the presence of NaY-60 and NaY-12 zeolites. The results of this study demonstrate that catalytic ozonation using NaY zeolites as catalysts is a promising alternative for micropollutant elimination in real-world wastewater matrices.

Effects of dissolved organic matter and halogen ions on phototransformation of pharmaceuticals and personal care products in aquatic environments

Photochemical reactions contribute to the attenuation and transformation of pharmaceuticals and personal care products (PPCPs) in surface natural waters. Nevertheless, effects of DOM and halogen ions on phototransformation of PPCPs remain elusive. This work selected disparate PPCPs as target pollutants to investigate their aquatic phototransformation processes. Results show that PPCPs containing multiple electron-donating groups (-OH, -NH2, -OR, etc.) are more reactive with photochemically produced reactive intermediates (PPRIs) such as triplet DOM (3DOM*), singlet oxygen (1O2), and reactive halogen species (RHSs), relative to PPCPs containing electron-withdrawing groups (-NOR, -COOR, -OCR, etc.). The generation of RHSs as a result of the coexistance of DOM and halide ions changed the contribution of PPRIs to the photochemical conversion of PPCPs during their migration from fresh water to seawater. For PPCPs (AMP, SMZ, PN, NOR, CIP, etc) with highly reactive groups toward RHSs, the generation of RHSs facilitated their photolysis in halide ion-rich waters, where Cl- plays a critical role in the photochemical transformation of PPCPs. Density functional theory (DFT) calculations showed that single electron transfer and H-abstraction are main reaction pathways of RHSs with the PPCPs. These results demonstate the irreplaceable roles of PPRIs and revealing the underlying reaction mechanisms during the phototransformation of PPCPs, which contributes to a better understanding of the environmental behaviors of PPCPs in complex aquatic environments.

Parental exposure to antidepressants has lasting effects on offspring? A case study with zebrafish

Fish have common neurotransmitter pathways with humans, exhibiting a significant degree of conservation and homology. Thus, exposure to fluoxetine makes fish potentially susceptible to biochemical and physiological changes, similarly to what is observed in humans. Over the years, several studies demonstrated the potential effects of fluoxetine on different fish species and at different levels of biological organization. However, the effects of parental exposure to unexposed offspring remain largely unknown. The consequences of 15-day parental exposure to relevant concentrations of fluoxetine (100 and 1000 ng/L) were assessed on offspring using zebrafish as a model organism. Parental exposure resulted in offspring early hatching, non-inflation of the swimming bladder, increased malformation frequency, decreased heart rate and blood flow, and reduced growth. Additionally, a significant behavioral impairment was also found (reduced startle response, basal locomotor activity, and altered non-associative learning during early stages and a negative geotaxis and scototaxis, reduced thigmotaxis, and anti-social behavior at later life stages). These behavior alterations are consistent with decreased anxiety, a significant increase in the expression of the monoaminergic genes slc6a4a (sert), slc6a3 (dat), slc18a2 (vmat2), mao, tph1a, and th2, and altered levels of monoaminergic neurotransmitters. Alterations in behavior, expression of monoaminergic genes, and neurotransmitter levels persisted until offspring adulthood. Given the high conservation of neuronal pathways between fish and humans, data show the possibility of potential transgenerational and multigenerational effects of pharmaceuticals' exposure. These results reinforce the need for transgenerational and multigenerational studies in fish, under realistic scenarios, to provide realistic insights into the impact of these pharmaceuticals.

The Conversion and Degradation of Sulphaguanidine under UV and Electron Beam Irradiation Using Fluorescence

The work presents a spectral-luminescent study of the sulfaguanidine transformation in water under a pulsed e-beam and UV irradiation of an UVb-04 bactericidal mercury lamp (from 180 to 275 nm), KrCl (222 nm), XeBr (282 nm) and XeCl (308 nm) excilamps. Fluorescent decay curves have been used in our analysis of the sulfaguanidine decomposition. The conversion of antibiotic under e-beam irradiation for up to 1 min was more than 80%, compared with UV radiation: UVb-04-26%, XeBr - 20%. KrCl and XeCl - about 10%. At the end of 64 min of irradiation with UVb-04 and XeBr lamps, the conversion was 99%. During irradiation with these lamps, sulfaguanidine almost completely decomposed and passed into the final fluorescent photoproducts. After e-beam irradiated at the end of 13 min the decrease in sulfaguanidine was 93%. At the same time, the formation of sulfaguanidine transformation products was minimal compared to UV irradiation. The effect of UV irradiation and a powerful e-beam on the decomposition mechanisms of sulfaguanidine are significantly different, which is manifested in various changes in the absorption and fluorescence spectra.

Transcriptomic profiles of brains in juvenile Atlantic cod (Gadus morhua) exposed to pharmaceuticals and personal care products from a wastewater treatment plant discharge

Pharmaceuticals and personal care products (PPCPs) are frequently detected in marine environments, posing a threat to aquatic organisms. Our previous research demonstrated the occurrence of neuroactive compounds in effluent and sediments from a wastewater treatment plant (WWTP) in a fjord North of Stavanger, the fourth-largest city in Norway. To better understand the influence of PPCP mixtures on fish, Atlantic cod (Gadus morhua) were caged for one month in 3 locations: site 1 (reference), site 2 (WWTP discharge), and site 3 (6.7 km west of discharge). Transcriptomic profiling was conducted in the brains of exposed fish and detection of PPCPs in WWTP effluent and muscle fillets were determined. Caffeine (47.8 ng/L), benzotriazole (10.9 ng/L), N,N-diethyl-meta-toluamide (DEET) (5.6 ng/L), methyl-1H-benzotriazole (5.5 ng/L), trimethoprim (3.4 ng/L), carbamazepine (2.1 ng/L), and nortriptyline (0.4 ng/L) were detected in the WWTP effluent. Octocrylene concentrations were observed in muscle tissue at all sites and ranged from 53 to 193 ng/g. Nervous system function and endocrine system disorders were the top enriched disease and function pathways predicted in male and female fish at site 2, with the top shared canonical pathways involved with estrogen receptor and Sirtuin signaling. At the discharge site, predicted disease and functional responses in female brains were involved in cellular assembly, organization, and function, tissue development, and nervous system development, whereas male brains were involved in connective tissue development, function, and disorders, nervous system development and function, and neurological disease. The top shared canonical pathways in females and males were involved in fatty acid activation and tight junction signaling. This study suggests that pseudopersistent, chronic exposure of native juvenile Atlantic cod from this ecosystem to PPCPs may alter neuroendocrine and neuron development.

Chlorpromazine's impact on Mytilus galloprovincialis: a multi-faceted investigation

The antipsychotic chlorpromazine (Cpz) has raised concern as a pharmaceutical effluent due to its wide medical applications. Moreover, its potent pro-oxidant properties and impact on the cell viability of the marine mollusc Mytilus galloprovincialis, even at low concentrations (ng/L), have been noted. Based on this evidence, in this study, we investigated the physiological effects of Cpz on M. galloprovincialis, to elucidate its fate within the organism, in terms of bioaccumulation, biotransformation, byssus changes and stress responses of the cellular thiolome. Histological and indicators of vitality analyses were also performed to better evaluate the influence of the drug on the morphology and cell viability of the digestive gland. To this end, two different concentrations of Cpz (Cpz I (12 ng/L or 37 pM) and Cpz II (12 μg/L or 37 nM)) were administered to mussels over 14 days. Cpz accumulation in the digestive gland significantly increased with water concentration (BCF of Cpz I and Cpz II). Biochemical analyses indicated lysosomal dysfunction, reflected in elevated total Cathepsin D activity and compromised lysosomal membrane stability. Stress-related and metal-buffering proteins (GST and metallothionein) responded to both Cpz concentrations. Cpz I induced phase I biotransformation activity (CYP450-dependent EROD), while Cpz II triggered caspase-3 activation, indicative of detoxification overload. Histological analysis revealed digestive gland atrophy, epithelial thinning, haemocyte infiltration, and brown cell presence. Byssus analysis showed significant alterations. In conclusion, our study underscores Cpz-induced physiological and histological changes in M. galloprovincialis, posing potential implications for mussel health and confirming the utilisation of this mussel as an indication of Cpz ecotoxicity.

Ecological Risk Assessment of Organochlorine Pesticides and Polychlorinated Biphenyls in Coastal Sediments in China

Although the ecological risk of emerging contaminants is currently a research hotspot in China and abroad, few studies have investigated the ecological risk of pesticide pollutants in Chinese coastal sediments. In this study, nine pesticide pollutants included in the "List of New Key Pollutants for Control (2023 Edition)" issued by the Chinese government were used as the research objects, and the environmental exposure of pesticide pollutants in China's coastal sediments was analyzed. The baseline sediment quality criteria were deduced using the balanced distribution method, and a multi-level ecological risk assessment of pesticides in sediment was performed. The results showed that the nine pesticide pollutants were widespread in Chinese coastal sediments, with concentrations ranging from 0.01 ng·g-1 to 330 ng·g-1. The risk quotient assessment showed that endosulfan and DDT posed medium environmental risks to the Chinese coastal sediment environment, and PCBs posed medium risks in some bays of the East China Sea. The semi-probabilistic, optimized semi-probability evaluation and joint probability curve (JPC) assessments all show that endosulfan and DDT pose a certain degree of risk to the environment.

Mixture effects of pharmaceuticals carbamazepine, diclofenac and venlafaxine on Mytilus galloprovincialis mussel probed by metabolomics and proteogenomics combined approach

Exposure to single molecules under laboratory conditions has led to a better understanding of the mechanisms of action (MeOAs) and effects of pharmaceutical active compounds (PhACs) on non-target organisms. However, not taking the co-occurrence of contaminants in the environment and their possible interactions into account may lead to underestimation of their impacts. In this study, we combined untargeted metabolomics and proteogenomics approaches to assess the mixture effects of diclofenac, carbamazepine and venlafaxine on marine mussels (Mytilus galloprovincialis). Our multi-omics approach and data fusion strategy highlighted how such xenobiotic cocktails induce important cellular changes that can be harmful to marine bivalves. This response is mainly characterized by energy metabolism disruption, fatty acid degradation, protein synthesis and degradation, and the induction of endoplasmic reticulum stress and oxidative stress. The known MeOAs and molecular signatures of PhACs were taken into consideration to gain insight into the mixture effects, thereby revealing a potential additive effect. Multi-omics approaches on mussels as sentinels offer a comprehensive overview of molecular and cellular responses triggered by exposure to contaminant mixtures, even at environmental concentrations.

Effects of dissolved organic matter, pH and nutrient on ciprofloxacin bioaccumulation and toxicity in duckweed

Water pollution induced by antibiotics has garnered considerable concern, necessitating urgent and effective removal methods. This study focused on exploring ciprofloxacin (CIP) removal by duckweed and assessing CIP bioaccumulation and toxic effects within duckweed under varying dissolved organic matter categories, pH levels, and nutrient (nitrogen (N) and phosphorus (P)) levels. The results revealed the proficient and rapid elimination of CIP from water by duckweed, resulting in 86.17 % to 92.82 % removal efficiency at the end of the 7-day experiment. Across all exposure groups, varying degrees of CIP bioaccumulation in duckweed were evident, with uptake established as a primary pathway for CIP elimination within this plant. Additionally, five CIP metabolites were identified in duckweed tissues. Interestingly, the presence of humic acid (HA) and fulvic acid (FA) reduced CIP absorption by duckweed, with FA yielding a more pronounced impact. Optimal CIP removal was recorded at a pH of 7.5, while duckweed displayed heightened physiological stress induced by CIP at pH 8.5. Although the influence of N and P concentrations on CIP removal by duckweed was modest, excessive N and P levels intensified the physiological strain of CIP on duckweed.

Comprehensive study on the potential environmental risk of temporal antibiotic usage through wastewater discharges

Antibiotic residues can reach aquatic ecosystems through urban wastewater discharges, posing an ecotoxicological risk for aquatic organisms and favoring the development of bacterial resistance. To assess the emission rate and hazardousness of these compounds, it is important to carry out periodic chemical monitoring campaigns that provide information regarding the actual performance of wastewater treatment plants (WWTPs) and the potential impact of the treated wastewater in the aquatic environment. In this study, 18 of the most widely consumed antibiotics in Spain were determined by liquid chromatography-tandem mass spectrometry in both influent (IWW) and effluent wastewater (EWW) samples collected over four seasons along 2021-2022. Eleven antibiotics were detected in EWW with azithromycin, ciprofloxacin and levofloxacin showing the highest concentration levels (around 2 μg L-1 of azithromycin and 0.4 μg L-1 of quinolone compounds). Data showed that only 4 out of the 11 compounds were removed by more than 50 % in the WWTP, with sulfamethoxazole standing out with an average removal efficiency >80 %. The risk that treated water could pose to the aquatic environment was also assessed, with 6 compounds indicating a potential environmental risk by exceeding established ecotoxicological and resistance thresholds. Based on the risk assessment, the WWTP removal efficiency required to reduce such risk for antibiotics was estimated. In addition, pooled wastewater samples were screened by LC coupled to high resolution mass spectrometry with ion mobility separation, searching for metabolites and transformation products of the antibiotics investigated to widen future research. Studies like this are crucial to map the impact of antibiotic pollution and to provide the basis for designing water quality and risk prevention monitoring programs.

Single and combined effects of caffeine and salicylic acid on mussel Mytilus galloprovincialis: Changes at histomorphological, molecular and biochemical levels

Caffeine (CAF) and salicylic acid (SA) are frequently detected in waterbody, though information on their biological impact is poor. This work assesses the effects of CAF (5ng/L to 10µg/L) and SA (0.05µg/L to 100µg/L) alone and combined as CAF+SA (5ng/L+0.05µg/L to 10µg/L+100µg/L) on mussel Mytilus galloprovincialis under 12-days exposure by histomorphology of digestive gland and oxidative stress defense at molecular and biochemical levels. Besides evaluating tissue accumulation, absence of histomorphological damage and haemocyte infiltration highlighted activation of defensive mechanisms. Up-regulation of Cu/Zn-sod, Mn-sod, cat and gst combined with increased catalase and glutathione S-transferase activity were found in CAF-exposed mussels, while SA reduced ROS production and mitochondrial activity. CAF+SA exposure induced differential responses, and the integrated biomarker response (IBR) revealed more pronounced effects of SA than CAF. These results enlarge knowledge on pharmaceuticals impact on non-target organisms, emphasizing the need for proper environmental risk assessment.

Identifying knowledge gaps in understanding the effects of selective serotonin reuptake inhibitors (SSRIs) on fish behaviour

Selective serotonin reuptake inhibitors (SSRIs) are a class of antidepressants increasingly prescribed to treat patients with clinical depression. As a result of the significant negative impact of the COVID-19 pandemic on the population's mental health, its consumption is expected to increase even more. The high consumption of these substances leads to their environmental dissemination, with evidence of their ability to compromise molecular, biochemical, physiological, and behavioural endpoints in non-target organisms. This study aimed to provide a critical review of the current knowledge regarding the effects of SSRI antidepressants on fish ecologically relevant behaviours and personality-dependent traits. A literature review shows limited data concerning the impact of fish personality on their responses to contaminants and how such responses could be influenced by SSRIs. This lack of information may be attributable to a lack of widely adopted standardized protocols for evaluating behavioural responses in fish. The existing studies examining the effects of SSRIs across various biological levels overlook the intra-specific variations in behaviour and physiology associated with different personality patterns or coping styles. Consequently, some effects may remain undetected, such as variations in coping styles and the capacity to handle environmental stressors. This oversight could potentially result in long-term effects with ecological implications. Data support the need for more studies to understand the impact of SSRIs on personality-dependent traits and how they may impair fitness-related behaviours. Given the considerable cross-species similarity in the personality dimensions, the collected data may allow new insights into the correlation between personality and animal fitness.

Exploring the Impact of Contaminants of Emerging Concern on Fish and Invertebrates Physiology in the Mediterranean Sea

In this historical context, the Mediterranean Sea faces an increasing threat from emerging pollutants such as pharmaceuticals, personal care products, heavy metals, pesticides and microplastics, which pose a serious risk to the environment and human health. In this regard, aquatic invertebrates and fish are particularly vulnerable to the toxic effects of these pollutants, and several species have been identified as bio-indicators for their detection. Among these, bivalve molluscs and elasmobranchs are now widely used as bio-indicators to accurately assess the effects of contaminants. The study focuses on the catshark Scyliorhinus canicular and on the Mediterranean mussel Mytilus galloprovincialis. The first one is a useful indicator of localised contamination levels due to its exposure to pollutants that accumulate on the seabed. Moreover, it has a high trophic position and plays an important role in the Mediterranean Sea ecosystem. The bivalve mollusc Mytilus galloprovincialis, on the other hand, being a filter-feeding organism, can acquire and bioaccumulate foreign particles present in its environment. Additionally, because it is also a species of commercial interest, it has a direct impact on human health. In conclusion, the increasing presence of emerging pollutants in the Mediterranean Sea is a serious issue that requires immediate attention. Bivalve molluscs and elasmobranchs are two examples of bio-indicators that must be used to precisely determine the effects of these pollutants on the marine ecosystem and human health.

Prioritization of pharmaceuticals and personal care products in the surface waters of Korea: Application of an optimized risk-based methods

The occurrence of PPCPs in aquatic environments and their potential adverse effects on aquatic organisms have raised worldwide concerns. To address this issue, a study was conducted to analyze 137 selected PPCPs in Korean surface waters, and an optimized risk-based prioritization was performed. The results revealed that 120 PPCPs were detected, with 98 quantified at concentrations ranging from few ng/L to 42,733 ng/L for metformin. The 95% upper confidence limit (UCL95) of the mean value of the measured environmental concentration (MEC) for Metformin was about eight times higher than the second highest compound, dimethyl phthalate, indicating that antidiabetic groups had the highest concentration among the therapeutic groups. An optimized risk-based prioritization was then assessed based on the multiplication of two indicators, the Frequency of Exceedance and the Extent of Exceedance of Predicted No-Effect Concentrations (PNECs), which can be calculated using the traditional risk quotient (RQ) approach. The study found that clotrimazole had the highest risk quotient value of 17.4, indicating a high risk to aquatic organisms, with seven and 13 compounds showing RQ values above 1 and 0.1, respectively. After considering the frequency of exceedance, clotrimazole still had the highest novel risk quotient (RQ_f) value of 17.4, with 99.6% of its MECs exceeding PNECs. However, the number of compounds with RQ_f values above 1 decreased from seven to five, with cetirizine and flubendazole being excluded. Furthermore, only 10 compounds exhibited RQ_f values above 0.1. The study also observed significant differences in the results between risk-based and exposure-based prioritization methods, with only five compounds, cetirizine, olmesartan, climbazole, sulfapyridine, and imidacloprid, identified in both methods. This finding highlights the importance of considering multiple methods for prioritizing chemicals, as different approaches may yield different results.

Critical review of phytoremediation for the removal of antibiotics and antibiotic resistance genes in wastewater

Antibiotics in wastewater are a growing environmental concern. Increased prescription and consumption rates have resulted in higher antibiotic wastewater concentration. Conventional wastewater treatment methods are often ineffective at antibiotic removal. Given the environmental risk of antibiotics and associated antibiotic resistant genes (ARGs), finding methods of improving antibiotic removal from wastewater is of great importance. Phytoremediation of antibiotics in wastewater, facilitated through constructed wetlands, has been explored in a growing number of studies. To assess the removal efficiency and treatment mechanisms of plants and microorganisms within constructed wetlands for specific antibiotics of major antibiotic classes, the present review paper considered and evaluated data from the most recent published research on the topics of bench scale hydroponic, lab and pilot scale constructed wetland, and full scale constructed wetland antibiotic remediation. Additionally, microbial and enzymatic antibiotic degradation, antibiotic-ARG correlation, and plant effect on ARGs were considered. It is concluded from the present review that plants readily uptake sulfonamide, macrolide, tetracycline, and fluoroquinolone antibiotics and that constructed wetlands are an effective applied phytoremediation strategy for the removal of antibiotics from wastewater through the mechanisms of microbial biodegradation, root sorption, plant uptake, translocation, and metabolization. More research is needed to better understand the effect of plants on microbial community and ARGs. This paper serves as a synthesis of information that will help guide future research and applied use of constructed wetlands in the field antibiotic phytoremediation and wastewater treatment.

Fitorremediación de cinco productos farmaceúticos registrados como contaminantes emergentes en medio acuoso empleando la especie Jacinto de Agua (Eichhornia crassipes)

La contaminación de los sistemas acuáticos de agua dulce constituye un problema ambiental recurrente en el ámbito mundial, que se agudiza cada vez más con la presencia frecuente de nuevos compuestos químicos, tal es el caso de los contaminantes emergentes, dentro de los cuales se incluyen los productos farmacéuticos. El objetivo de esta investigación fue estimar la capacidad de la especie jacinto de agua (Eichhornia crassipes) para remover del medio acuoso cinco fármacos altamente recetados y de venta libre como ciprofloxacina, ibuprofeno, sulfametaxazol, diclofenaco y acetaminofén. El trabajo se llevó a cabo en condiciones de invernadero a una temperatura de 25 0C y a un pH de 6,5; con una toma de muestras cada 24 h a diferentes concentraciones (3, 6, 9,12) mg/L. Para el análisis de las muestras se utilizó Espectrofotometría UV-VIS con lectura directa de las absorbancias de cada uno de los fármacos. Se empleó la metodología de superficies de respuesta para el análisis estadístico de los datos, lo que permitió determinar los modelos para establecer tiempos y concentraciones óptimas maximizando la absorción de cada producto farmacéutico, así como obtener las pendientes de crecimiento para definir hacia donde se puede proyectar el óptimo. Los principales resultados en este estudio indican que E. crassipes removió 95% de diclofenaco en soluciones acuosas con una concentración de 3 mg/L en un tiempo de 24 h, seguido de ciprofloxacina y acetaminofén con una remoción máxima de 91,18% y 71% a las 96 h, respectivamente. Mientras que los más bajos porcentajes de remoción se obtuvo para ibuprofeno y sulfametaxazol con 57,56% y 36%, respectivamente. En el presente estudio, se comprobó la alta capacidad de remoción E. crassipes de los cinco productos farmacéuticos en condiciones controladas, evidenciando una gran posibilidad de aplicación en el campo de la fitorremediación de contaminantes emergentes en medio acuoso, lo cual constituye un importante aporte en este ámbito de la investigación. Palabras clave: Fitorremediación, contaminantes emergentes, jacinto de agua (Eichhornia crassipes), superficie de respuesta

Study on the removal characteristics and degradation pathways of highly toxic and refractory organic pollutants in real pharmaceutical factory wastewater treated by a pilot-scale integrated process

Introduction

Pharmaceutical wastewater frequently contains high levels of toxic pollutants. If they are discharged untreated, they pose a threat to the environment. The traditional activated sludge process and the advanced oxidation process do not sufficiently remove toxic and conventional pollutants from pharmaceutical wastewater treatment plants (PWWTPs).

Methods

We designed a pilot-scale reaction system to reduce toxic organic pollutants and conventional pollutants from pharmaceutical wastewater during the biochemical reaction stage. This system included a continuous stirred tank reactor (CSTR), microbial electrolysis cells (MECs), an expanded sludge bed reactor (EGSB), and a moving bed biofilm reactor (MBBR). We used this system to further investigate the benzothiazole degradation pathway.

Results and discussion

The system effectively degraded the toxic pollutants (benzothiazole, pyridine, indole, and quinoline) and the conventional chemicals (COD, NH4+-N, TN). During the stable operation of the pilot-scale plant, the total removal rates of benzothiazole, indole, pyridine, and quinoline were 97.66, 94.13, 79.69, and 81.34%, respectively. The CSTR and MECs contributed the most to the removal of toxic pollutants, while the EGSB and MBBR contributed less to the removal of the four toxic pollutants. Benzothiazoles can be degraded via two pathways: the benzene ring-opening reaction and the heterocyclic ring-opening reaction. The heterocyclic ring-opening reaction was more important in degrading the benzothiazoles in this study.

Conclusion

This study provides feasible design alternatives for PWWTPs to remove both toxic and conventional pollutants at the same time.

Occurrence, spatial distribution, and potential risks of organic micropollutants in urban surface waters from qinghai, northwest China

Lack of knowledge on the destiny of organic micropollutants (OMPs) in the Tibetan Plateau region of China prevents the public from being aware of the need for protecting these unique aquatic ecosystems that are precious water resources and source areas of the Yellow River. To address this knowledge gap, this study systematically investigated the multi-residue analysis, distribution, and potential risks of six types of OMPs, namely, neonicotinoid pesticides (NEOs), fungicides, organophosphate esters (OPEs), organophosphorus pesticides (OPPs), psychoactive substances (PSs), and antidepressants (ADs), in surface waters of major cities in Qinghai. A total of 31 compounds, consisting of 8 NEOs, 1 fungicide, 12 OPEs, 2 OPPs, 5 PSs, and 3 ADs, were detected in >50% of the sites, showing their ubiquitous nature in the study area. Results showed that the total OMP concentration in surface water was 28.3-908 ng/L, and OPEs were the dominant composition (48.6%-97.4%). The risk quotient values of the detected diazinon and dursban regularly exceeded 1 for aquatic organisms at all sampling sites, indicating moderate-high chronic ecological risk. The joint probability curves showed that dursban and NEOs have higher risk levels than other OMPs. Although the results of the non-carcinogenic total hazard quotient of the OMPs in the surface water was less than 1 in all age groups and the carcinogenic risk was lower than the negligible risk level, the potential risks to children and infants were considerably greater and should not be underestimated. In addition to pollutant concentration and exposure duration, ingestion rate and body weight (BW) are also important factors affecting health risk, with BW having a negative effect. To the best of the authors' knowledge, this report is the first to describe OMP pollution in Qinghai, and the results provide new insight into the ecological security of the water resources of the Tibetan Plateau.

Mechanism of β-blocker biodegradation by wastewater microorganisms

The recalcitrant β-blockers have been widely detected in aquatic environments up to several hundred μg/L, which are major contributors to β1 antagonistic activities in wastewater. Their biodegradation mechanisms remain obscure, hindering the development of efficient removal techniques. This study constructed the biodegradation pathways for three typical β-blockers, namely atenolol, metoprolol, and propranolol, assessed the toxicity of their major biotransformation products, and identified the key enzyme catalyzing the O-dealkylation reaction leading to pollutant mineralization. Atenolol and metoprolol degradation was more efficient than that of propranolol by activated sludge, producing metoprolol acid (MTPA) as a major intermediate. Hydrogenophaga sp. YM1 isolated from activated sludge possess the α-ketoglutarate dependent dioxygenase (TfdA) responsible for O-dealkylation of MTPA and propranolol, producing 4-hydroxyphenylacetic acid (4-HPA) that can be further degraded and ultimately enters the TCA cycle. The role of TfdA was verified by proteomics, enzyme stimulation/inhibition tests, and gene knockout experiments. Molecular docking suggests its different interactions with MTPA and propranolol. Acetate facilitated the degradation of β-blockers efficiently. The results may shed light on enhanced biological removals of broader β-blockers and their transformation products in the environment.

Appraising efficacy of existing and advanced technologies for the remediation of beta-blockers from wastewater: A review

The discharge of emerging pollutants, such as beta-blockers (BB), has been recognized as one of the major threats to the environment due to the ecotoxicity associated with these emerging pollutants. The BB are prescribed to treat high blood pressure and cardiovascular diseases; however, even at lower concentration, these pollutants can pose eco-toxic impacts towards aquatic organisms. Additionally, owing to their recalcitrant nature, BB are not effectively removed through conventional technologies, such as activated sludge process, trickling filter and moving bed bioreactor; thus, it is essential to understand the degradation mechanism of BB in established as well as embryonic technologies, like adsorption, electro-oxidation, Fenton process, ultraviolet-based advance oxidation process, ozonation, membrane systems, wetlands and algal treatment. In this regard, this review articulates the recalcitrant nature of BB and their associated removal technologies. Moreover, the major advantages and limitations of these BB removal technologies along with the recent advancements with regard to the application of innovative materials and strategies have also been elucidated. Therefore, the present review intends to aid the researchers in improving the BB removal efficiency of these technologies, thus alleviating the problem of the release of BB into the environment.

Novel method in emerging environmental contaminants detection: Fiber optic sensors based on microfluidic chips

Recently, human industrial practices and certain activities have caused the widespread spread of emerging contaminants throughout the environmental matrix, even in trace amounts, which constitute a serious threat to human health and environmental ecology, and have therefore attracted the attention of research scholars. Different traditional techniques are used to monitor water pollutants, However, they still have some disadvantages such as high costs, ecological problems and treatment times, and require technicians and researchers to operate them effectively. There is therefore an urgent need to develop simple, inexpensive and highly sensitive methods to sense and detect these toxic environmental contaminants. Optical fiber microfluidic coupled sensors offer different advantages over other detection technologies, allowing manipulation of light through controlled microfluidics, precise detection results and good stability, and have therefore become a logical device for screening and identifying environmental contaminants. This paper reviews the application of fiber optic microfluidic sensors in emerging environmental contaminant detection, focusing on the characteristics of different emerging contaminant types, different types of fiber optic microfluidic sensors, methodological principles of detection, and specific emerging contaminant detection applications. The optical detection methods in fiber optic microfluidic chips and their respective advantages and disadvantages are analyzed in the discussion. The applications of fiber optic biochemical sensors in microfluidic chips, especially for the detection of emerging contaminants in the aqueous environment, such as personal care products, endocrine disruptors, and perfluorinated compounds, are reviewed. Finally, the prospects of fiber optic microfluidic coupled sensors in environmental detection and related fields are foreseen.

Study of degradation of norfloxacin antibiotic and their intermediates by natural solar photolysis

In this work, the photolysis of the antibiotic norfloxacin (NOR) and the formation of its photodegradation products were studied using UV and solar radiation. Their extraction was also assessed in Milli-Q water and secondary effluents from a wastewater treatment plant. The photolysis of NOR was chromatographically monitored. The structure of each degradation product is related to the reaction of NOR with reactive oxygen species (ROS), as confirmed using radical quenchers and mass spectrometry. Additionally, the feasibility of extracting NOR and its degradation products was assessed using a commercial solid phase extraction system. Photolysis results showed the formation of five degradation products, generated under exposure to both types of radiation. The decays in NOR concentrations for the solar and UV treatments were adjusted to pseudo first-order kinetics with apparent constant values of k_solar = 1.19 × 10^-3 s^-1 and k_UV = 3.84 × 10^-5 s^-1. Furthermore, the superoxide radical was the main participant species in the formation of the degradation products P3, P4, and P5. Species P1 and P2 do not need this radical for their formation. The presence of NOR in water opens the possibility of its photolysis by solar radiation. This work contributes to the understanding of the mechanisms that mediate its photodegradation, in addition to studying potential options for its determination and its photodegradation products in the sample treatment.

Ecological and human health risks of antibiotics in marine species through mass transfer from sea to land in a coastal area: A case study in Qinzhou Bay, the South China sea

Antibiotics have been detected in aquatic environment around the world. Understanding internal concentrations of antibiotics in organisms could further improve risk governance. In this study, we investigated the occurrence of seven sulfonamides, four tetracyclines, five fluoroquinolones, and five macrolides antibiotics in six fish, four crustaceans, and five mollusks species collected from Qinzhou Bay, an important part of the Beibu Gulf in the South China Sea in 2018. 19 of all the 21 target antibiotics were detectable in biota. The total concentrations of the antibiotics ranged from 15.2 to 182 ng/g dry weight in all marine organisms, with sulfonamides and macrolides being the most abundant antibiotics. Mollusks accumulated more antibiotics than fish and crustaceans, implying the species-specific bioaccumulation of antibiotics. The pH dependent partition coefficients of antibiotics exhibited significantly positive correlation with their concentrations in organisms. The ecological risk assessment suggested that marine species in Qinzhou Bay were threatened by azithromycin and norfloxacin. The annual mass loading of antibiotics from Qinzhou Bay to the coastal land area for human ingestion via marine fishery catches was 4.02 kg, with mollusks being the predominant migration contributor. The estimated daily intakes of erythromycin indicated that consumption of seafood from Qinzhou Bay posed considerable risks to children (2-5 years old). The results in this study provide important insights for antibiotics pollution assessment and risk management.

Spatial and temporal variations in anti-androgenic activity and environmental risk in a small river

The biological effects of multiple compounds have been widely investigated in aquatic environments. However, investigations of spatial and temporal variations in biological effects are rarely performed because they are time-consuming and labor-intensive. In this study, the variability of the anti-androgen, receptor-mediated activity of surface water samples was observed over 3 years using in vitro bioassays. Large-volume water samples were collected at one site upstream (Wer site) and two sites downstream (Sil and Nien sites) of a wastewater treatment plant (WWTP) outfall in the Holtemme River. Anti-AR activity was persistently present in all surface water samples over the three years. Large spatial variations in anti-androgenic activity were observed, with the lowest activity at the Wer site (mean concentration of 9.5 ± 7.2 μg flutamide equivalents/L) and the highest activity at the Sil site (mean concentration of 31.1 ± 12.0 μg flutamide equivalents/L) directly influenced by WWTP effluents. On the temporal scale, no distinct trend for anti-AR activity was observed among the seasons in all three years. The anti-androgenic activity at the upstream Wer site showed a decreasing trend from 2014 to 2016, indicating improved water quality. A novel bioanalytical-equivalent-based risk assessment method considering the frequency of risk occurrence was developed and then utilized to assess the environmental risk of anti-androgenic activity in the Holtemme River. The results revealed that the highest risk was present at the Sil site, while the risk was considerably reduced at the Nien site. The risk at the upstream Wer site was the lowest.

An overall assessment of the effects of antidepressant paroxetine on aquatic organisms and human cells

Paroxetine (PRX) is one of the most used antidepressants and an emerging contaminant with potential harmful effects to the environment and human health. The present study investigates in detail the toxic potential of PRX using a battery of bioassays on fresh- and marine species, marine bacteria, and human lymphocytes. All the tested organisms and human lymphocytes were exposed at concentrations ranging from μg L^-1 to mg L^-1. It was found that PRX can cause toxic effects to aquatic organisms at environmental relevant concentrations (μg L^-1 level). A significant effect of PRX was observed in all tested algal species especially at the first 24 h. However, differences in responses and sensitivities among the tested algal species were observed. The most sensitive organism was found to be Dunaliella tertiolecta with IC₅₀ = 0.092 mg L^-1 (72 h). In the case of Aliivibrio fischeri, EC₅₀ values were determined to be 16.65, 14.31 and 14.41 mg L^-1 for 5, 15 and 30 min of exposure, respectively. PRX also induced cytotoxic and genotoxic effects in human lymphocytes. A dose-dependent increase in micronucleus frequencies was occurred at all tested concentrations with a statistically significant increase in micronucleus frequencies at the medium to high PRX tested concentrations. The findings of the present study expand the available toxicity profile of PRX on aquatic organisms and the knowledge about the potential risk of PRX to induce genotoxic effects in cultured human lymphocytes.

Antibiotics in sewage treatment plants, receiving water bodies and groundwater of Chennai city and the suburb, South India: Occurrence, removal efficiencies, and risk assessment

The presence of antibiotics in the aqueous environment can alter the water microbiome, inducing antimicrobial resistance genes. Hence, the occurrence of 18 antibiotics belonging to sulfonamides, fluoroquinolones, tetracyclines, phenicols, and macrolides classes were investigated in surface water, groundwater, and sewage treatment plants in Chennai city and the suburbs. Fluoroquinolones had the maximum detection frequency in both influent and effluent samples of urban and suburban STPs, with ofloxacin and ciprofloxacin showing the highest influent concentrations. Erythromycin was the predominant antibiotic in surface water samples with an average concentration of 194.4 ng/L. All the detected antibiotic concentrations were higher in the Buckingham Canal compared to those in Adyar and Cooum rivers, possibly due to direct sewer outfalls in the canal. In groundwater samples, ciprofloxacin showed the highest levels with an average of 20.48 ng/L and the concentrations were comparable to those of surface water. The average sulfamethazine concentration in groundwater (5.2 ng/L) was found to be slightly higher than that of the surface water and much higher than the STP influent concentrations. High levels of ciprofloxacin and sulfamethazine in groundwater may be because of their high solubility and wide use. Moreover, erythromycin was completely removed after treatment in urban STPs; FQs showed relatively lesser removal efficiency (2.4-54%) in urban STPs and (8-44%) in suburban STP. Tetracyclines and phenicols were not detected in any of the samples. Ciprofloxacin and azithromycin in surface water pose a high risk in terms of estimated antibiotic resistance. This study revealed that the measured surface water concentration of antibiotics were 500 times higher for some compounds than the predicted calculated concentrations from STP effluents. Therefore, we suspect the direct sewage outlets or open drains might play an important role in contaminating surface water bodies in Chennai city.

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.

Novel composite of Zn/Ti-layered double hydroxide coupled with MXene for the efficient photocatalytic degradation of pharmaceuticals

In the present study, a hybrid photocatalyst of Zn/Ti layered double hydroxide (LDH) coupled with MXene - Ti₃C₂ was synthesized for the first time and applied in photocatalytic degradation of acetaminophen and ibuprofen, two commonly present in the natural environment and prone to accumulate in the aquatic ecosystem pharmaceuticals. The effect of MXene content (0.5 wt%, 2.5 wt%, and 5 wt%) on the photocatalytic activity of LDH/MXene composite was investigated. The composite of LDH/MXene containing 2.5 wt% of MXene revealed the highest photocatalytic activity in the degradation of acetaminophen (100% within 40 min) and ibuprofen (99.7% within 60 min). Furthermore, an improvement in acetaminophen and ibuprofen mineralization was observed for the composite material. Meanwhile, the introduction of interfering ions (Na⁺, Ca²⁺, Mg²⁺, Cl^-, SO₄^2-) in the model seawater did not affect the removal efficiency of both pharmaceuticals. The photocatalytic experiment performed in the four subsequent cycles, as well as FTIR, TEM, and XPS analyses after the photodegradation process confirmed the excellent stability and reusability of the prepared composite material. In order to evaluate the effect of various reactive oxidizing species (ROS) on the photocatalytic process, the trapping experiment was applied. It was noticed that •O₂^- had the main contribution in photocatalytic degradation of acetaminophen, while •OH and h⁺ mainly affected the degradation of ibuprofen. Finally, based on the results of Mott Schottky analysis, bandgap calculation, and ROS trapping experiment, the possible mechanism for pharmaceuticals degradation was proposed. This research illustrates the feasibility and novelty of the treatment of pharmaceuticals by LDH/MXene composites, implying that MXene plays a significant role in the electron-hole separation and thus high photocatalytic activity.

Pharmaceutical pollution of hospital effluents and municipal wastewaters of Eastern Canada

Quantification of drugs residues in wastewaters of different sources could help better understand contamination pathways, eventually leading to effluent regulation. However, limited data are available for hospital-derived wastewaters. Here, an analytical method based on automated on-line solid-phase extraction liquid chromatography tandem mass spectrometry (on-line SPE - UPLC-MS/MS) was developed for the quantification of multi-class pharmaceuticals in wastewaters. Filtrate phase and suspended solids (SPM) were both considered to evaluate the distribution of targeted analytes. Experimental design optimization involved testing different chromatographic columns, on-line SPE columns, and loading conditions for the filtrate phase, and different organic solvents and cleanup strategies for suspended solids. The selected methods were validated with suitable limits of detection, recovery, accuracy, and precision. A total of 30 hospital effluents and 6 wastewater treatment plants were sampled to evaluate concentrations in real field-collected samples. Certain pharmaceuticals were quantified at high levels such as caffeine at 670,000 ng/L in hospital wastewaters and hydroxyibuprofen at 49,000 ng/L in WWTP influents. SPM samples also had high contaminant concentrations such as ibuprofen at 31,000 ng/g in hospital effluents, fluoxetine at 529 ng/g in WWTP influents or clarithromycin at 295 ng/g in WWTP effluents. Distribution coefficients (K_d) and particle-associated fractions (Φ) indicate that pharmaceuticals tend to have better affinity to suspended solids in hospital wastewater than in municipal wastewaters. The results also bring arguments for at source treatment of these specific effluents before their introduction into urban wastewater systems.

Occurrence and distribution of azithromycin in wastewater treatment plants, seawater, and sediments of the northern part of the Persian Gulf around Bushehr port: A comparison with Pre-COVID 19 pandemic

One of the environmental effects of COVID 19 is the contamination of ecosystems with antibiotics due to their high consumption to treat this disease. Many years ago, the distribution of antibiotics including azithromycin (Azi) in wastewater treatment plants in Bushehr city, seawater, and sediment of the Persian Gulf has been investigated. As Azi has been prescribed to COVID 19 patients, contamination of the environment with this drug can also be assumed. Thus, we decided to examine this hypothesis by repeating our previous study during COVID 19 period. We collected wastewater samples from influent, effluent, and different units of three wastewater treatment plants (WWTPs) including one municipal WWTP (Plant A) and two hospital-WWTPs (Plant B and C). Seawater and adjusted sediments were gathered from 8 stations located in the Persian Gulf in two seasons to evaluate the special and temporal variation. The results showed a huge growth of Azi pollution in all studied matrixes. The mean Azi values in the influent of Plant A, B, and C were 145 ng/L, 110 ng/L, and 896 ng/L, which represented an 9, 6, and 48-time increase compared with those obtained in 2017 (before COVID 19). The Azi removal efficiency had a different behavior compared to before COVID 19. The mean concentration of Azi in seawater and sediment samples was 9 ng/L and 6 ng/g, which was 3 and 4-fold higher than the previous study. Opposed to our former study, the Azi amount in the aqueous phase was less subjected to temporal seasonal variations. Our observations indicated the wide distribution of Azi in the environment and a future threat of intense growth of antibiotic resistance in ecosystems.

Investigation of membrane fouling and mechanism induced by extracellular organic matter during long-term exposure to pharmaceuticals and personal care products

This study investigated ultrafiltration membrane fouling by extracellular organic matter (EOM) and the mechanism operating during long-term exposure to pharmaceuticals and personal care products. The results indicated that carbamazepine and diclofenac in algal-laden water altered the filtration flux and membrane fouling by EOM. Exposure to low-concentration carbamazepine (0.25 μg/L) improved the filtration flux and the total (R_tot) and reversible fouling resistance (R_c), whereas the filtration flux and R_tot and R_c were reduced when EOM was used during long-term exposure to high carbamazepine concentrations (>1 μg/L). Both R_tot and R_c were increased when algae were exposed to 0.25 μg/L diclofenac, whereas the filtration flux and R_tot and R_c were alleviated when algae were exposed to >1 μg/L diclofenac. Moreover, carbamazepine and diclofenac (0.25 μg/L - 1000 μg/L) in water enhanced the irreversible fouling resistance (R_b) when ultrafiltration was used to treat algal-laden waters. The mechanism indicated that membrane fouling induced by standard blocking was transformed to complete blocking when EOM was exposed to high levels of carbamazepine (>0.25 μg/L) in the initial filtration process, whereas cake layer formation played an important role during the later filtration process; with low carbamazepine levels (0.25 μg/L), standard blocking of EOM was dominant during the entire filtration process. The membrane fouling mechanism also changed when algal-laden waters were exposed to diclofenac, the membrane fouling was transformed from complete blocking to standard blocking when DFC was present in the initial filtration process, whereas cake layer formation exerted an important role during the late filtration process. This research provides important information on the long-term risks caused by pharmaceutical and personal care products and potential threats to membrane treatment.

Occurrence and ecological risk assessment of antibiotic residues in urban wastewater discharged into the coastal environment of the Persian Gulf (the case of Bandar Abbas)

This is the first attempt to detect antibiotic residues released into the Persian Gulf marine environment. In particular, this study quantifies and assesses the ecological risks of amoxicillin (AMX) and azithromycin (AZM) residues in wastewater outfalls from Bandar Abbas, one of the major coastal cities in southern Iran. The wastewater effluent samples were collected from two main wastewater discharging stations, Gursuzan and Suru, between December 2020 and February 2021. High-performance liquid chromatography (HPLC) analysis revealed the average concentration (± 95% CL) of AMX were 460 ± 230.0 μg L^-1 and 280 ± 100.6 μg L^-1 in Gursuzan and Suru stations. Mean AZM concentrations were also 264 ± 10.59 μg L^-1 and 295 ± 89.75 μg L^-1 in these stations, respectively. Pooled data indicated that there are 335.17 ± 105.11 and 288.17 ± 37.94 μg of AMX and AZM residues in the wastewater per liter. The values of potential ecological risk, hazard quotient (HQ), were extensively above 10 (AMX: 90,586.5 and AZM: 5541.7) which suggest that these substances have a high health risk for the ecosystem and public. Given that Bandar Abbas wastewater treatment plant (WWTP) outlets are discharged at about 500 to 700 L s^-1, the daily maximum potential AMX and AZM released were estimated to be 19.05 (± 0.283) × 10³ and 14.74 (± 0.113) × 10³ g day^-1, respectively (α = 0.05). Our findings show that there is a concerning volume of antibiotic residues released into the northern Persian Gulf, and hence urgent policies and actions are necessary to reduce this pollution.

Invertebrates differentially bioaccumulate pharmaceuticals: Implications for routine biomonitoring

Surface water quality monitoring programs have been developed to examine traditional contaminants, such as persistent organic pollutants (POPs). However, urbanization, which is increasing around the world, is increasing discharge of treated wastewater and raw sewage in many regions. Pharmaceuticals and their metabolites represent typical markers of such trajectories in urbanization. We selected an ongoing monitoring program, which was designed for routine surveillance of nonionizable POPs in different aquatic matrices, to examine the occurrence of 67 pharmaceuticals and their metabolites in water and multiple bioindicator matrices: benthic invertebrates, juvenile fish, and adult fish (plasma and muscle tissue) from ten river systems with varying levels of watershed development. In addition, we placed zebra mussels and passive samplers in situ for a fixed period. A statistically significant relationship between pharmaceutical levels in passive samplers and biota was found for caged zebra mussels and benthic invertebrates, while only a few pharmaceuticals were identified in fish matrices. Invertebrates, which have received relatively limited study for pharmaceutical bioaccumulation, accumulated more pharmaceuticals than fish, up to thirty different substances. The highest concentration was observed for sertraline in zebra mussels and telmisartan in benthic invertebrates (83 and 31 ng/g ww, respectively). Our results across diverse study systems indicate that ongoing surface water quality monitoring programs, which were originally designed for traditional organic pollutants, need to be revised to account for bioaccumulation dynamics of pharmaceuticals and other ionizable contaminants. Aquatic monitoring programs routinely examine accumulation of nonionizable organic pollutants; however, we identified that these efforts need to be revised to account for bioaccumulation of ionizable contaminants, which reached higher levels in invertebrates than in fish.

The overall assessment of simultaneous photocatalytic degradation of Cimetidine and Amisulpride by using chemical and genotoxicological approaches

Pharmaceutical Active Compounds (PhACs) are of particular interest among the emerging contaminants detected in the aquatic environment. Commonly, PhACs exist as complex mixtures in aquatic systems, causing potential adverse effects to the environment and human health than those of individual compounds. Based on the increasing interest in the contamination of water resources by PhACs, the photocatalytic degradation of Cimetidine and Amisulpride as a mixture in combination with their toxic and genotoxic effects before and after the treatment were evaluated for the first time. The toxic, genotoxic and cytotoxic effects were investigated using the Trypan Blue Exclusion Test and the Cytokinesis Block MicroNucleus (CBMN) assay in cultured human lymphocytes. The photocatalytic degradation of the PhACs was studied in ultrapure water and environmentally relevant matrices using UV-A and visible (Vis) irradiation and C-TiO₂ (TiO₂ Kronos vlp 7000) as photocatalyst. High removal percentages were observed for both compounds under UV-A and Vis irradiation in ultrapure water. In lake and drinking water a slower degradation rate was shown that could be attributed to the complex composition of these matrices. Scavenging experiments highlighted the significant role of h⁺ and O₂^●- in the degradation mechanisms under both irradiation sources. Oxidation, dealkylation and deamination were the main degradation pathways. Regarding the individual compounds, Amisulpride was found to be more cytotoxic than Cimetidine. No significant differences of the genotoxic effects during the treatment were observed. However, a slight increase in cytotoxicity was observed at the first stages of the process. At the end of the process under both UV-A and Vis light, non-significant cytotoxic/toxic effects were observed. Based on the results, heterogeneous photocatalysis can be considered as an effective process for the treatment of complex mixtures without the formation of harmful transformation products.

Health effects and risks associated with the occurrence of pharmaceuticals and their metabolites in marine organisms and seafood

Pharmaceuticals and their metabolites are continuously invading the marine environment due to their input from the land such as their disposal into the drains and sewers which is mostly followed by their transfer into wastewater treatment plants (WWTPs). Their incomplete removal in WWTPs introduces pharmaceuticals into oceans and surface water. To date, various pharmaceuticals and their metabolites have been detected in marine environment. Their occurrence in marine organisms raises concerns regarding toxic effects and development of drug resistant genes. Therefore, it is crucial to review the health effects and risks associated with the presence of pharmaceuticals and their metabolites in marine organisms and seafood. This is an important study area which is related to the availability of seafood and its quality. Hence, this study provides a critical review of the information available in literature which relates to the occurrence and toxic effects of pharmaceuticals in marine organisms and seafood. This was initiated through conducting a literature search focussing on articles investigating the occurrence and effects of pharmaceuticals and their metabolites in marine organisms and seafood. In general, most studies on the monitoring of pharmaceuticals and their metabolites in marine environment are conducted in well developed countries such as Europe while research in developing countries is still limited. Pharmaceuticals present in freshwater are mostly found in seawater and marine organisms. Furthermore, the toxicity caused by different pharmaceutical mixtures was observed to be more severe than that of individual compounds.

Occurrence, Comparison and Priority Identification of Antibiotics in Surface Water and Sediment in Urbanized River: A Case Study of Suzhou Creek in Shanghai

Antibiotics in water have attracted increasing attention due to their potential threat to aquatic ecosystems and public health. Most previous studies have focused on heavily polluted environments, while ignoring urbanized rivers with high population density. Taking Suzhou Creek in Shanghai as an example, this study attempted to explore the antibiotic pollution characteristics of typical urbanized rivers. Further, it screened out priority antibiotics so as to provide reference for the regular monitoring of antibiotics in urban surface water in the study’s later stage. Four classes of 27 antibiotics in surface water samples and sediment samples were detected and analyzed by SPE-UPLC-MS/MS under both wet season and dry season. Results demonstrate that the total amount of antibiotics detected reached 1936.9 ng/L and 337.3 ng/g in water samples and sediment samples, respectively. Through Pearson correlation analysis, it can be shown that there is a very significant correlation between a variety of antibiotics in water and sediment. The results of ecological risk assessment based on risk quotient (RQ) show that certain antibiotics presented high and medium risk to the surrounding ecosystem. Finally, the priority antibiotics selected by optimized priority screening method were EM, SPD, CLR and RTM. Therefore, we have proven that the antibiotics being discharged in urbanized rivers show different types of antibiotics, while presenting a toxicological risk to certain species.

Application of Microbial Fuel Cell (MFC) for Pharmaceutical Wastewater Treatment: An Overview and Future Perspectives

Pharmaceutical wastewater (PWW) is rapidly growing into one of the world’s most serious environmental and public health issues. Existing wastewater treatment systems carry numerous loopholes in supplying the ever-increasing need for potable water resulting from rises in population, urbanization, and industrial growth, and the volume of wastewater produced is growing each day. At present, conventional treatment methods, such as coagulation, sedimentation, oxidation, membrane filtration, flocculation, etc., are used to treat PWW. In contrast to these, the application of microbial fuel cells (MFCs) for decontaminating PWW can be a promising technology to replace these methods. MFC technologies have become a trending research topic in recent times. MFCs have also garnered the interest of researchers worldwide as a promising environmental remediation technique. This review extensively discusses the flaws in standalone conventional processes and the integration of MFCs to enhance electricity production and contaminant removal rates, especially with respect to PWW. This article also summarizes the studies reported on various antibiotics and wastes from pharmaceutical industries treated by MFCs, and their efficiencies. Furthermore, the review explains why further research is needed to establish the actual efficiency of MFCs to achieve sustainable, environmentally friendly, and cost-effective wastewater treatment. A brief on technoeconomic impacts has also been made to provide a glimpse of the way these technologies might replace present-day conventional methods.

Hospital effluents as sources of antibiotics residues, resistant bacteria and heavy metals in Benin

This study aims to evaluate the bacteriological, chemical, and toxicological quality of hospital effluents in Benin. Eighteen (18) samples were collected from the south and north of Benin, and poles were set up. Bacteriological analysis was carried out according to the French National Organization for Standardization (AFNOR) standard. Identification of the bacterial species isolated was performed using the API 20E gallery and specific biochemical tests. Antibiotic residues were searched by following ELISA kit instructions. 109 bacterial isolates were obtained, with a predominance of non-enterobacteria (37.7%) and Acinetobacter spp. (24.6%), followed by Klebsiella spp. (11.48%); S. aureus and Coagulase-negative staphylococci (CoNS) were isolated at the same frequency (6.5%). Physico-chemical and toxicological parameter analyses showed that they were in conformity with the standards of discharge into the environment. The pH, temperature, electrical conductivity, total solids below, P-redox and suspended solids measured were, on average, 6.83, 27.21 °C, 693.68 µS/cm, 693.68 mg/l, 1.68 mV and 0.15 mg/l, respectively. For heavy metals, cadmium was most prevalent (0.22 mg/l), followed by nickel (0.18 mg/l) and lead (0.03 mg/l). The average antibiotic residue concentrations ranged from 0.043 to 7.65 µg/l. Ciprofloxacin, metronidazole and sulfamethoxazole had the highest residue concentrations of 7.65 ± 2.272 µg/l, 6.61 ± 0.051 µg/l and 3.88 ± 3.088 µg/l, respectively. The heavy metal concentrations obtained were below those required by Benin standards. These effluents therefore present health and environmental risks. It is then more than necessary to develop treatment methods for them before their rejection into the natural environment.

Transformation and fate of pharmaceuticals, personal care products, and per- and polyfluoroalkyl substances during aerobic digestion of anaerobically digested sludge

Post-anaerobic aerobic digestion (PAAD) is a promising strategy to further reduce the volume and improve the quality of anaerobically digested sludge (ADS). However, the effect of PAAD process on the fate of pharmaceuticals and personal care products (PPCPs) and per- and polyfluoroalkyl substances (PFAS) remains largely unknown. In this study, fourteen PPCPs and fifteen PFAS were detected in ADS and evaluated regarding their fate and transformation in a laboratory aerobic digester operated with a hydraulic retention time of 13 days under 22 ℃. Twelve PPCPs demonstrated significant (p < 0.05) decrease in their total concentrations (dissolved and adsorbed fractions combined) with six compounds presenting substantial transformation (> 80%) after aerobic digestion. On the contrary, PFAS were not removed and their concentrations were either increased (increasing ratio: 91 - 571%) or consistent in the sludge during PAAD process, suggesting their recalcitrance to post aerobic digestion. More than half of PPCPs and PFAS demonstrated medium to strong sorption onto solids with their solid fraction higher than 50% in the ADS. After PAAD process, sorption of four PPCPs and three PFAAs to solids was enhanced in sludge.

Ultrasound-assisted extraction as an easy-to-perform analytical methodology for monitoring ibuprofen and its main metabolites in mussels

Non-steroidal anti-inflammatory drugs (NSAIDs) have been reported to be the main pharmaceutical class accumulated in seafood. Among them, ibuprofen (IBU) is of special concern as it is used worldwide to treat common pain, does not require a medical prescription, it is often taken in a high daily dose, and has been reported to cause potential adverse effects on aquatic organisms. IBU is highly transformed into hydroxy- and carboxy-metabolites and/or degradation products generated not only after its administration but also during wastewater treatment or in the environment. These compounds can be present in the environment at higher concentrations than IBU and present higher toxicity. In this work, a low-cost and affordable routine analytical method was developed and validated for the first-time determination of IBU and its main metabolites in mussels. The method is based on ultrasound-assisted extraction (UAE), clean-up by dispersive solid-phase extraction (d-SPE) and analytical determination by liquid chromatography-tandem mass spectrometry. Box-Behnken experimental design was used for method optimisation to better evaluate the influence and interactions of UAE and d-SPE variables. Extraction recoveries were in the range from 81 to 115%. Precision, expressed as relative standard deviation, was lower than 7%. Method detection limits were in the range from 0.1 to 1.9 ng g⁻¹ dry weight. The method was successfully applied to wild mussels.