Occurrences and removal of pharmaceuticals and personal care products (PPCPs) in drinking water and water/sewage treatment plants: A review

Zebrafish embryos as an in vivo model to investigate cisplatin-induced oxidative stress and apoptosis in mitochondrion-rich ionocytes

Pharmaceuticals and personal care products are emerging environmental pollutants. Cisplatin, one of the most widely used platinum-based chemotherapeutic agents, has been found to contaminate aquatic environments. Using zebrafish embryos as a model, cisplatin was previously found to impair skin ionocytes and ion regulation. The purpose of this study was to further investigate how cisplatin damages ionocytes. Zebrafish embryos were exposed to cisplatin (0, 50, and 100 μM) for 96 h (4-100 h post-fertilization) and then stained with fluorescent dyes to reveal mitochondrial activity (rhodamine123), apoptosis (acridine orange), and oxidative stress (CellROX/MitoSOX) in ionocytes of living embryos. Results showed that cisplatin exposure decreased rhodamine 123-labeled ionocytes, induced oxidative stress in ionocytes, and promoted apoptosis in a concentration-dependent manner. Quantitative PCR analysis showed that mRNA levels of antioxidative genes (sod1, sod2, gpx1a, and cat) and an apoptotic gene (caps3a) were induced. In the time-course experiment at 96-98 h post-fertilization, cisplatin increased oxidative stress and apoptosis in ionocytes in a time-dependent manner. In conclusion, this study demonstrates that cisplatin exposure induces oxidative stress, mitochondrial damage, and apoptosis in ionocytes of zebrafish embryos.

First report on the occurrence of pharmaceuticals and cocaine in the coastal waters of Santa Catarina, Brazil, and its related ecological risk assessment

The worldwide occurrence of pharmaceuticals and personal care products (PPCPs) in aquatic ecosystems is reason for public concern. These emerging micropollutants include a large and diverse group of organic compounds, with continuous input, high environmental persistence and potential threat to biota and human health. The aim of this study was to evaluate, for the first time, the occurrence of twenty-seven PPCPs of various therapeutic classes (including cocaine and its primary metabolite, benzoylecgonine), in the coastal waters of Santa Catarina, southern Brazil. Water samples were taken in November 2020, during the low tide periods, at eight sampling points located along the coast of Santa Catarina, covering its entire geographical extension. Sampling was carried out in triplicate and at different depths of the water column. Nine compounds were detected through liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS): caffeine (12.58-119.80 ng/L), diclofenac (1.34-7.92 ng/L), atenolol (1.13-2.50 ng/L), losartan (0.43-3.20 ng/L), acetaminophen (0.21-10.04 ng/L), orphenadrine (0.07-0.09 ng/L), cocaine (0.02-0.17 ng/L), benzoylecgonine (0.01-1.1 ng/L) and carbamazepine (0.02-0.27 ng/L). The highest occurrence of these compounds was detected in the northern and central coastal region of Santa Catarina, namely in Penha and Palhoça cities. Moreover, the risk assessment showed that almost compounds (atenolol, benzoylecgonine, carbamazepine, cocaine and orphenadrine) presented no ecological risk in the recorded concentrations. However, a few compounds suggest low (caffeine and diclofenac) to moderate (acetaminophen and losartan) risk taking into consideration the acute and chronic effects for the three trophic levels (algae, crustacean and fish) tested. These compounds are usually found in areas with high population density, aggravated by tourism, because of the sanitary sewage and solid waste. Although in low concentrations, the occurrence of these chemical compounds can imply deleterious effects on the environmental health of Santa Catarina coastal zone, and therefore deserve more attention by the public authorities and environmental agencies.

Occurrence, distribution and risk of pharmaceutical and personal care products in the Haihe River sediments, China

In the aquatic environment, pharmaceuticals and personal care products (PPCPs) detected in sediments are rising health concerns to human and aquatic ecosystem. The migration of PPCPs in the sediments poses a potential risk to surface water and groundwater environment. Insight on the spatial distribution and vertical profile of PPCPs in sediments at the regional scale is valuable for comprehensive prevention of PPCP risk. The Haihe River is one of the major water systems for the rapid development of urbanization, industrialization and agriculture in Northern China. The study aimed to characterize the occurrence, distribution and ecological risks of PPCPs in the sediments of the Haihe River, especially to investigate the vertical distribution of PPCPs using core sediments. High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to analyze 24 selected PPCPs in sediment samples. In total, 11 PPCPs were detected, and the detected concentrations (0-1.26 ng g^-1) were, lower than in other water bodies in literature (0-24.4 ng g^-1). The sediments of the Haihe River located in the Tianjin downtown were most-severely polluted, with the highest cumulative concentration of PPCPs of 9.45 ng g^-1, indicating the relatively high contribution of human consumption of PPCPs for the megacity. Spearman correlation analysis shows that both of the TOC contents and particle size distribution can influence the migration and deposition of PPCPs. The risk assessment results showed that the current level of PPCPs has no severe adverse effects on aquatic organisms in the Haihe River. However, special attention should be paid to the environmental risks caused by the migration of PPCPs with high loading and mobility (such as sulfamethoxazole).

A critical review on paracetamol removal from different aqueous matrices by Fenton and Fenton-based processes, and their combined methods

Paracetamol (PCT), also known as acetaminophen, is a drug used to treat fever and mild to moderate pain. After consumption by animals and humans, it is excreted through the urine to the sewer systems, wastewater treatment plants, and other aquatic/natural environments. It has been detected in trace amounts in effluents of wastewater plant treatments, sewage sludge, hospital wastewaters, surface waters, and drinking water. PCT can cause genetic code damage, oxidative degradation of lipids, and denaturation of protein in cells, and its toxicity has been well-proven in bacteria, algae, macrophytes, protozoan, and fishes. To avoid its harmful health problems over living beings, powerful Fenton and Fenton-based treatments as pre-eminent advanced oxidation processes (AOPs) have been developed because of the inefficient treatment by conventional treatments. This paper presents a comprehensive and critical review over the application of such Fenton technologies to remove PCT from natural waters, synthetic wastewaters, and real wastewaters. The characteristics and main results obtained using Fenton, photo-Fenton, electro-Fenton, and photoelectro-Fenton are described, making special emphasis in the oxidative action of the generated reactive oxygen species. Hybrid processes based on the coupling with ultrasounds, gamma radiation, photocatalysis, photoelectrocatalysis, zero-valent iron-activated persulfate, adsorption, and microbial fuel cells, are analyzed. Sequential treatments involving the initiation with plasma gliding arc discharge and post-biological process are detailed. Comparative results with other available AOPs are also described and discussed. Finally, 13 aromatic by-products and 9 short-linear aliphatic carboxylic acid detected during the PCT removal by Fenton and Fenton-based processes are reported, with the proposal of three parallel pathways for its initial degradation.

Historical development and prospect of intimately coupling photocatalysis and biological technology for pollutant treatment in sewage: A review

Through the synergistic effect of photocatalysis and biodegradation, intimately coupling photocatalysis and biological (ICPB) technology could improve the removal rate and mineralization rate of refractory pollutants and reduce the toxicity of intermediate products. ICPB system was characterized with the advantages of simple operation, low energy consumption and high treatment efficiency. As a new sewage treatment technology, ICPB system has shown great potential in the treatment of refractory pollutants, and has been widely concerned. In this study, the research progress of photocatalyst, carrier and biofilm in ICPB system were discussed, and the degradation mechanism was introduced. The shortcomings of the current ICPB system were pointed out, and the possible research directions of ICPB in the future were proposed. This review aimed to deepen the understanding of ICPB technology and promoted the further development of ICPB technology in the treatment of refractory pollutants.

Catalytic oxidation of 4-acetamidophenol with Fe3+-enhanced Cu0 particles: In-site generation and activation of hydrogen peroxide

Cu⁰ coupled with O₂ was used to degrade contaminant due to in-site generation and catalysis of H₂O₂, while the low reactivity and active dismutation reaction of Cu⁺ refrained the performance at acidic condition. In this study, the removal rate of 4-acetamidophenol increased from 27 % to 83.4 % with Fe³⁺ spiked into the Cu⁰ system within 60 min •OH was the primary reactive species in the Fe³⁺/Cu⁰ system. In the Fe³⁺/Cu⁰ system, Cu⁰ was corroded to form Cu⁺ by H⁺ and O₂, and then Cu⁺ interacted with O₂ generating H₂O₂, and meanwhile Fe³⁺ was reduced to Fe²⁺ by Cu⁺ and Cu⁰; Consequently, Cu⁺ and Fe²⁺ induced H₂O₂ to produce •OH, but Fe²⁺ was easier to catalyze H₂O₂ than Cu⁺ at acidic pH. Except for fulvic acid, common water matrix including sulfate ion, phosphate ion, chloride ion and nitrate ion had no inhibition effect on the degradation of 4-acetamidophenol in the Fe³⁺/Cu⁰ system. over 62 % of 4-acetamidophenol in tap water, Hou-lake water and well water was greatly oxidized by the Fe³⁺/Cu⁰ system. Furthermore, the amount of total dissolved copper decreased to 0.895 mg/L by the method of alkali precipitation in the Fe³⁺/Cu⁰ system. The study provided a theoretical direction to the Fe³⁺-enhanced Cu⁰ system for purifying wastewater.

Removal of microorganic pollutants in aquatic environment: The utilization of Fe(VI)

Microorganic pollutants (MOPs) in aquatic environment with low levels but high toxicity are harmful to ecosystem and human health. Fe(VI) has a dual-functional role in oxidation and coagulation, and can effectively remove MOPs, heavy metal, phosphate, particulates and colloids. Moreover, Fe(VI) can combine with traditional coagulants, or use as a pretreatment for membrane treatment because of its characters to generate nanoparticles by degradation in water. Based on the relevant toxicity experiments, Fe(VI) had been proved to be safe for the efficient treatment of MOPs. For better utilization of Fe(VI), its oxidation and coagulation mechanisms are summarized, and the knowledge about the control parameters, utilization methods, and toxicity effect for Fe(VI) application are reviewed in this paper. pH, different valences of iron, environmental substances, and other parameters are summarized in this study to clarify the important factors in the treatment of MOPs with Fe(VI). In the future study, aiming at cost reduction in Fe(VI) preparation, transportation and storage, enhancement of oxidation in the intermediate state, and better understanding the mechanism between interface and Fe(VI) oxidation will help promote the application of Fe(VI) in the removal of MOPs. This study offers guidelines for the application and development of Fe(VI) for the treatment of MOPs in aquatic environment.

Integrated adsorption and biological removal of the emerging contaminants ibuprofen, naproxen, atrazine, diazinon, and carbaryl in a horizontal tubular bioreactor

Groundwater and surface water bodies may have contaminants from urban, industrial, or agricultural wastewater, including emerging contaminants (ECs) or micropollutants (MPs). Frequently, they are not efficiently removed by microbial action due to their minimal concentration in water and the low microbiota affinity for complex compounds. This work developed a process allowing the adsorption of contaminants and their simultaneous biodegradation using horizontal tubular fixed-bed biofilm reactors (HTR). Each HTR has two zones: an equalizer-aerator of the incoming liquid flow and a fixed bed zone. This zone was packed with a mixed support material consisting of granular bio-activated carbon (Bio-GAC) and porous material that increases the bed permeability, thus decreasing the pressure drop. Five microbial communities were acclimated and immobilized in granular activated carbon (GAC) to obtain different specialized Bio-GAC particles able to remove the micropollutants ibuprofen, naproxen, atrazine, carbaryl, and diazinon. The Bio-GAC particles were transferred to HTRs continuously run in microaerophilia at several MPs loading rates. Under these conditions, the removal efficiencies of MPs, except atrazine and carbaryl, were around 100.

Efficient capture of radioactive iodine by ZIF-8 derived porous carbon

Due to the rapid diffusion of radioactive iodine, the demand for safe and efficient capture and storage of radioactive iodine is increasing worldwide. The use of porous carbon materials to capture iodine has aroused great interest. This work prepared porous carbon materials derived from polymetallic oxides of the zeolitic imidazolate framework (ZIF) by pyrolysis at 1000 °C. The carbon materials (CZIF-1000) have a high specific surface area of about 1110 m2/g and a total pore volume of 0.92 cm3/g. Adsorption studies have shown that the CZIF-1000 had significant adsorption performance for iodine, and the adsorption capacity can reach 790.8 mg/g at 8h. The potential mechanism of adsorption is that the carbonization causes the charge-transfer interaction and pore size distribution. Compared with the conventional adsorbents, the adsorbents showed faster kinetics and high extraction capacity for iodine. This experiment provides an effective method for designing a highly efficient adsorbent for iodine and broadens the ideas for developing new iodine extraction adsorbents.

Environmentally relevant concentration of caffeine-effect on activity and circadian rhythm in wild perch

We studied the ecological consequences of widespread caffeine contamination by conducting an experiment focused on changes in the behavioral traits of wild perch (Perca fluviatilis) after waterborne exposure to 10 μg L^-1 of caffeine. We monitored fish swimming performance during both light and dark conditions to study the effect of caffeine on fish activity and circadian rhythm, using a novel three-dimensional tracking system that enabled positioning even in complete darkness. All individuals underwent three behavioral trials-before exposure, after 24 h of exposure, and after 5 days of exposure. We did not observe any effect of the given caffeine concentration on fish activity under light or dark conditions. Regardless of caffeine exposure, fish swimming performance was significantly affected by both the light-dark conditions and repeating of behavioral trials. Individuals in both treatments swam significantly more during the light condition and their activity increased with time as follows: before exposure < after 24 h of exposure < after 5 days of exposure. We confirmed that the three-dimensional automated tracking system based on infrared sensors was highly effective for conducting behavioral experiments under completely dark conditions.

Method optimisation and application based on solid phase extraction of non steroidal anti-inflammatory drugs, antiretroviral drugs, and a lipid regulator from coastal areas of Durban, South Africa

This study presents an optimized method that is applicable in monitoring the occurrence of pharmaceuticals in a wide range of aquatic environments. The optimised Solid Phase Extraction method is based on Bond Elut Plexa cartridges for the identification and quantification of three non-steroidal anti-inflammatory drugs, three antiretroviral drugs and a lipid regulator in the coastal area of Durban city, South Africa covering four seasons. The extracted compounds are qualitatively and quantitatively detected by a high-performance liquid phase chromatographic instrument coupled to a photodiode array detector. The recoveries range from 62 to 110% with a Relative Standard Deviation of 0.56−4.68%, respectively, for the determination of emtricitabine, tenofovir, naproxen, diclofenac, ibuprofen, efavirenz, and gemfibrozil. The analytical method is validated by spiking estuarine water samples with 5 µg L− 1 of a mixture containing the target pharmaceuticals and the matrix detection limit is established to be 0.62–1.78 µg L− 1 for the target compounds. The optimized method is applied to seasonal monitoring of pharmaceuticals at chosen study sites from winter and spring of 2019 and summer and autumn of 2020. The results indicate the concentration of the pharmaceuticals studied varies with the type of aquatic environment and season.

Fate and removal of emerging contaminants in anaerobic fluidized membrane bioreactor filled with thermoplastic gel as biofilm support

The Anaerobic Fluidized Membrane Bioreactor (AnFMBR) is a membrane-based hybrid technology that can overcome the limitations of conventional anaerobic sewage treatment. Although previous studies have demonstrated excellent performance in the removal of conventional organic pollutants, further research into the removal paths of emerging contaminants (ECs) under various operating conditions is required for proper design and development of the AnFMBR technology. Regarding this, the fate of four ECs in a lab-scale AnFMBR filled with thermoplastic gel for biofilm growth was investigated under various Hydraulic Retention Time (HRT) conditions. When the HRT was 13 h, diclofenac and 17β-estradiol were efficiently removed at 93% and 72% respectively. Even after an HRT reduction to 6.5 h, the system was still able to maintain high ECs removals (74% for diclofenac and 69% for 17β-estradiol). However, irrespective of HRT operational condition, smaller removals of 17a-ethinylestradiol (37-52%) were observed, while only marginal removals of amoxicillin were achieved (5-29%). Biotransformation was attributed as the main route for ECs removal. The results obtained in this study indicate that the membrane-based hybrid AnFMBR can be used to treat the target ECs without influence on anaerobic process. The technology had better removal efficiency for diclofenac and 17β-estradiol. However, the AnFMBR system exhibits high variability in EC removal and low capacity for amoxicillin removal, implying that a combination of other processes is still required to properly avoid the release of these contaminants into the environment.

Cuttlefish bone powder as an efficient solid-phase extraction sorbent of anti-SARS-CoV-2 drugs in environmental water

Many antiviral drugs were developed to counteract coronavirus disease, 2019 (COVID-19) with severe acute respiratory syndrome. Therefore, the scientific community's efforts have focused on the detection and quantification of antiviral compounds currently being tested for COVID-19 treatment. Cuttlefish bone powder (CFBP) has been used for the first time as solid-phase extraction (SPE) sorbent for the extraction of SARS CoV-2 antiviral drugs (chloroquine, ritonavir and indomethacin) from water samples. An effective and sensitive method was developed by combining SPE and liquid chromatography- UV detection (LC-UV). An experimental design was applied for the optimization of extraction process. Experimental variables were optimized using Doehlert matrix. The developed method included 50 mg of CFBP sorbent, 20 mL of water sample at pH = 9 and 5 mL of ACN/KH₂PO₄ buffer solution (80:20, v/v) in the elution step. For validation of the method, selectivity, linearity precision, and sensitivity were evaluated. Extraction recovery percentage of all Sars cov-2 antivirals were above 98.2%. The detection and quantification limits were between 0.1 and 0.5 µg L⁻¹ and 0.6 and 2 µg L⁻¹, respectively. The current study suggested that CFBP has the application potential for the enhanced SPE of SARS CoV-2 antiviral drugs from water samples.

Underlying mechanisms of promoted formation of haloacetic acids disinfection byproducts after indometacin degradation by non-thermal discharge plasma

Indometacin (IDM), as a kind of non-steroidal anti-inflammatory drugs, has ecological and health risks, which is the potential precursor of chlorination disinfection byproducts (DBPs). Non-thermal discharge plasma was attempted to eliminate IDM and control subsequent DBPs formation. Satisfactory removal performance for IDM was realized by the plasma oxidation; almost 100% of IDM was removed within 2 min. Relatively greater removal efficiency was gained at a higher plasma voltage and a lower pH level. Electron paramagnetic resonance spectrometer revealed that reactive species ·OH, O₂·^-, and ¹O₂ were responsible for IDM decomposition. Based on analyses of Fourier transform infrared spectroscopy, two-dimensional correlation spectroscopy, three-dimensional fluorescence spectrum, and gas chromatography-mass spectrometer, attacks of reactive species resulted in sequence breakages in functional groups of IDM, leading to production of small molecular alcohols, acids, and amines. Possible decomposition pathways of IDM were proposed. The produced acetamide and 1H-indol-5-ol were important precursors of DBPs. Formation and toxicity of nitrogen-containing DBPs were dramatically inhibited after IDM degradation; however, those of haloacetic acids were strengthened. The relevant roadmaps among DBPs and degradation intermediates were figured out. This study revealed the underlying mechanisms of IDM degradation by discharge plasma and its potential risks in chlorination disinfection.

Nano delivery systems to the rescue of ciprofloxacin against resistant bacteria "E. coli; P. aeruginosa; Saureus; and MRSA" and their infections

Ciprofloxacin (CIP) a broad-spectrum antibiotic, is used extensively for the treatment of diverse infections and diseases of bacteria origin, and this includes infections caused by E. coli; P. aeruginosa; S. aureus; and MRSA. This extensive use of CIP has therefore led to an increase in resistance by these infection causing organisms. Nano delivery systems has recently proven to be a possible solution to resistance to these organisms. They have been applied as a strategy to improve the target specificity of CIP against infections and diseases caused by these organisms, thereby maximising the efficacy of CIP to overcome the resistance. Herein, we proffer a brief overview of the mechanisms of resistance; the causes of resistance; and the various approaches employed to overcome this resistance. The review then proceeds to critically evaluate various nano delivery systems including inorganic based nanoparticles; lipid-based nanoparticles; capsules, dendrimers, hydrogels, micelles, and polymeric nanoparticles; and others; that have been applied for the delivery of CIP against E. coli; P. aeruginosa; S. aureus; and MRSA infections. Finally, the review highlights future areas of research, for the optimisation of various nano delivery systems, to maximise the therapeutic efficacy of CIP against these organisms. This review confirms the potential of nano delivery systems, for addressing the challenges of resistance to caused by E. coli; P. aeruginosa; S. aureus; and MRSA to CIP.

Sonophotocatalysis—Limits and Possibilities for Synergistic Effects

Advanced oxidation processes are promising techniques for water remediation and degradation of micropollutants in aqueous systems. Since single processes such as sonolysis and photocatalysis exhibit limitations, combined AOP systems can enhance degradation efficiency. The present work addresses the synergistic intensification potential of an ultrasound-assisted photocatalysis (sonophotocatalysis) for bisphenol A degradation with a low-frequency sonotrode (f = 20 kHz) in a batch-system. The effects of energy input and suspended photocatalyst dosage (TiO2-nanoparticle, m = 0–0.5 g/L) were investigated. To understand the synergistic effects, the sonication characteristics were investigated by bubble-field analysis, hydrophone measurements, and chemiluminescence of luminol to identify cavitation areas due to the generation of hydroxyl radicals. Comparing the sonophotocatalysis with sonolysis and photocatalysis (incl. mechanical stirring), synergies up to 295% and degradation rates of up to 1.35 min−1 were achieved. Besides the proof of synergistic intensification, the investigation of energy efficiency for a degradation degree of 80% shows that a process optimization can be realized. Thus, it could be demonstrated that there is an effective limit of energy input depending on the TiO2 dosage.

Micropollutant removal and disinfection byproduct control by sequential peroxymonosulfate-UV treatment in water: A case study with sulfamethoxazole

UV/peroxymonosulfate (UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole (SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product (DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane (TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief (5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5-1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation.

Novel laccase from Xylaria polymorpha and its efficiency in the biotransformation of pharmaceuticals: Optimization of operational conditions, comparative effect of redox-mediators and toxicity studies

The promising potentials of biocatalytic treatment processes in the removal of micropollutants whilst eliminating health and environmental hazards have attracted great attention in recent years. This current work investigated the biotransformation efficiency of a novel laccase from Xylaria polymorpha (XPL) in comparison with commercial laccases from Trametes versicolor (TVL) and Aspergillus sp. (ASL). XPL exhibited better oxidation performance (95.7%) on AMX than TVL (92.8%) and ASL (90.5%). Optimization of operational conditions revealed that AMX was best oxidized at pH 5, temperature (30 °C), and concentration (1.0 mg L^-1). The investigation carried out to determine the effect of redox mediators revealed violuric acid (VLA) as the best redox mediator. The laccase stability experiments elucidated that the oxidation of AMX is time and mediator concentration dependent with ABTS exhibiting highest deactivation of XPL active sites. Two metabolic products; amoxicillin penilloic acid and 5-hydroxy-6-(4-hydroxyphenyl)- 3-(1,3-thiazolidin-2-yl)piperazin-2-one of AMX were obtained through Liquid Chromatography-Mass Spectrometry (LC-MS) analyses. The toxicity assessments carried out after oxidation of AMX by XPL showed 94% and 97% reduced toxicity on Artemia salina and Aliivibrio fischeri respectively. The study further underscored the efficiency of biocatalytic-mediator technology in the transformation of complex micropollutants into less toxic substances in an eco-friendly way.

Effect-Directed Analysis Based on the Reduced Human Transcriptome (RHT) to Identify Organic Contaminants in Source and Tap Waters along the Yangtze River

Since a large number of contaminants are detected in source waters (SWs) and tap waters (TWs), it is important to perform a comprehensive effect evaluation and key contributor identification. A reduced human transcriptome (RHT)-based effect-directed analysis, which consisted of a concentration-dependent RHT to reveal the comprehensive effects and noteworthy pathways and systematic identification of key contributors based on the interactions between compounds and pathway effects, was developed and applied to typical SWs and TWs along the Yangtze River. By RHT, 42% more differentially expressed genes and 33% more pathways were identified in the middle and lower reaches, indicating heavier pollution. Hormone and immune pathways were prioritized based on the detection frequency, sensitivity, and removal efficiency, among which the estrogen receptor pathway was the most noteworthy. Consistent with RHT, estrogenic effects were widespread along the Yangtze River based on in vitro evaluations. Furthermore, 38 of 100 targets, 39 pathway-related suspects, and 16 estrogenic nontargets were systematically identified. Among them, diethylstilbestrol was the dominant contributor, with the estradiol equivalent (EEQ) significantly correlated with EEQ_water. In addition, zearalenone and niclosamide explained up to 54% of the EEQ_water. The RHT-based EDA method could support the effect evaluation, contributor identification, and risk management of micropolluted waters.

Dynamic SPME-SERS Induced by Electric Field: Toward In Situ Monitoring of Pharmaceuticals and Personal Care Products

The core of the surface-enhanced Raman spectroscopy (SERS)-based techniques for dynamic monitoring is to realize rapid and reversible adsorption. Herein, the integration technology of electro-enhanced adsorption, solid-phase microextraction, and surface-enhanced Raman spectroscopy (EE-SPME-SERS) was developed to obtain sensitive, ultrafast, and reversible SERS response toward in situ monitoring of pharmaceuticals and personal care products (PPCPs). In the EE-SPME-SERS method, a roughened Ag fiber with Au modification (r-Ag/Au fiber) was used as the SERS substrate, SPME sorbent, and working electrode. The r-Ag/Au fiber displayed good SERS sensitivity, ultrahigh photostability, and adsorption properties. The adsorption efficiency of benzidine was 76 times accelerated in EE-SPME-SERS compared to that in static adsorption. The whole process of "sampling and detection" in EE-SPME-SERS can be finished within 1 s. Reversible adsorption and desorption can be achieved in situ by switching the direction of electric field, and the regeneration process takes only a few minutes. Simulated release of benzidine from household wastewater was in situ and dynamically monitored using this strategy. EE-SPME-SERS was proved universal for ionized PPCPs and can detect multicomponents simultaneously. In addition, EE-SPME-SERS showed very good analytical properties. Great potential of EE-SPME-SERS can be expected in environmental monitoring.

Challenges of TiO2 heterogeneous photocatalysis on cytostatic compounds degradation: state of the art

The following work provides a perspective on the degradation of cytostatic pollutants through TiO₂ heterogeneous photocatalysis. Cytostatic drugs are emerging pollutants used for cancer treatment found in hospital and domestic wastewater. Small amounts of cytostatic pollutants may pose severe health problems in human beings, animals, and plants after prolonged contact. This research presents a general review of some water treatment methods, such as aerobic activated sludge, enzymatic degradation, nanofiltration and chlorination, that have been used for the degradation or elimination of cytostatic drugs in wastewater. In recent years, photocatalysis has become important to solve this problem; these advanced oxidation process uses pure and modified TiO₂ to degrade cytostatic contaminants and convert them into non-harmful substances or to eliminate them completely. This work contains a comprehensive review of the heterogeneous photocatalysis process and mechanism, and its application on the removal of cytostatic pollutants. Even if research on the topic is still scarce, this literature review provides interesting highlights on the scope of the research field, and the path such research could follow.

Efficient with low-cost removal and adsorption mechanisms of norfloxacin, ciprofloxacin and ofloxacin on modified thermal kaolin: experimental and theoretical studies

Quinolone antibiotics (QNs) can be potential hazard to environment and human. Combination of experimental and theoretical studies was used to analyze the adsorption properties of norfloxacin, ciprofloxacin and ofloxacin on modified thermally activated kaolin (KL). Main factors (calcination temperature, dose, pH, cations and regeneration) affecting the adsorption were discussed. Adsorption processes fit the pseudo-second order kinetic and Langmuir model well. The adsorption removal of norfloxacin, ciprofloxacin and ofloxacin can reach 88.53%, 89.43% and 91.46%, respectively. Cations inhibited adsorption, and AlS-KLB can maintain 80% efficiency in five cycles under optimal conditions. Simulations showed that the materials had good adsorption capacity for QNs, and the "①" of KL had the best capacity. Simulations explain the adsorption mechanism: F, H, O atoms of QNs are covalently bonded to O atoms from KL, Al₂O₃ and Al (OH)₃, C atoms from amorphous carbon and H atoms from C-H and Al (OH)₃. The Al atoms of Al₂O₃ and Al, Si atoms of KL are ionically bonded to F, H, O atoms of QNs. This study shed new light on the removal of QNs by providing low-cost and efficient modified KL and elucidating the adsorption mechanism in conjunction with DFT simulations.

Fingerprinting pharmaceuticals of multiple sources at a provincial watershed scale

Pharmaceutical residues in the aquatic environment have increasingly attracted public concerns but their fingerprint of sources remain unclear at a watershed scale. This study systematically explored pharmaceutical residues in effluent of 8 different type of sources in a provincial watershed in China using a multi-category protocol of pharmaceutical quantification. Seventy-seven out of 94 target compounds from 6 categories were quantified in effluent, up to 71,318 ng L^-1 in total from urban hospital sources with 20 antibiotics and 32 others. The spectrum of the quantified compounds in effluent significantly differentiated the urban (hospitals, domestic sewages, and WWTPs), rural (health centers and domestic sewages), and agricultural production sources (poultry and swine breeding yards, aquaculture ponds, and paddy fields). Compounds of non-steroidal anti-inflammation drugs (NSAIDs), cardiovascular drugs (CVs), and central nervous drugs (CNs) could fingerprint the three groups of sources. However, the three categories contributed 7 out of 10 compounds with high risk (risk quotient >1.0) to the aquatic environment identified by the eco-environmental risk assessment. No high-risk compounds were identified in effluent of urban WWTPs. Findings of this study suggest source identification and compound spectrum fingerprinting are crucial for studies on pharmaceutical residues in the aquatic environment, especially the complexity of pharmaceutical residues in source effluents for exploring source-sink dynamics at a watershed scale.

A review on the adsorption mechanism of different organic contaminants by covalent organic framework (COF) from the aquatic environment

Recently, covalent organic frameworks (COFs) have gained significant attention as a promising material for the elimination of various organic pollutants due to their distinctive characteristics such as high surface area, adjustable porosity, high removal efficiency, and recyclability. The efficiency and selectivity of COFs depend on the decorated functional group and the pore size of the chemical structure. Hence, this review highlights the adsorption removal mechanism of different organic contaminants such as (pharmaceutical and personal care products, pesticides, dyes, and industrial by-products) by COFs from an aqueous solution. Spectroscopic techniques and theoretical calculation methods are introduced to understand the mechanism of the adsorption process. Also, a comparison between the performance of COFs and other adsorbents was discussed. Furthermore, future research directions and challenges encountered in the removal of organic contaminants by COFs are discussed.

Nitrogen-doped carbon nanosheets with Fe-based nanoparticles for highly efficient degradation of antibiotics and sulfate ion enhancement effect

Developing Fe-based catalysts with high-effective and environmentally friendly features in Fenton-like system for treating wastewater is still a challenge. Novel nitrogen-doped carbon nanosheets with Fe⁰/Fe₃C nano-particles (Fe@NCS-900) were prepared through a simple solvent-free strategy by pyrolyzing the mixture of 2,6-diaminopyridine and ferric chloride hexahydrate under 900 °C. The Fe@NCS-900 possessed almost 100% removal efficiency and 66.5% mineralization rate for the degradation of CBZ in 10 min. Moreover, the Fe@NCS-900 exhibited an apparent first-order constant as high as 0.8809 min^-1, which is 22 and 29 times higher than that of the commercial Fe⁰ and traditional Fenton system, respectively, which could be attribute to the high graphitization degree and rich nitrogen content. Besides, the results of the radical quenching experiments, electron paramagnetic resonance (EPR) and the probe experiments demonstrated that a large number of high valent iron species (Fe (IV)) besides singlet oxygen (¹O₂) and superoxide radicals (O₂^•-) existed and contributed to the CBZ degradation. More interestingly, the addition of coexisting anion SO₄^2- in the reaction system could significantly boost the concentration of •OH and SO₄^•- by 28.3 times and 9.7 times, respectively, resulting in the increase of the apparent first-order constant by 5.9 times (5.1733 min^-1), which was entirely different from previous reports that SO₄^2- had no effect on the catalytic activity or even displayed slightly inhibitory effect. In addition, the catalyst exhibited broad pH adaptability in the pH range of 2-9. The intermediate products of CBZ degradation were investigated by liquid chromatography mass spectrometry (LC-MS) and the degradation pathway was proposed. This paper provides new insights for developing a promising Fe-based nitrogen-doped catalyst for practical wastewater treatment.

Wastewater effluent affects behaviour and metabolomic endpoints in damselfly larvae

Wastewater treatment plant effluents have been identified as a major contributor to increasing anthropogenic pollution in aquatic environments worldwide. Yet, little is known about the potentially adverse effects of wastewater treatment plant effluent on aquatic invertebrates. In this study, we assessed effects of wastewater effluent on the behaviour and metabolic profiles of damselfly larvae (Coenagrion hastulatum), a common aquatic invertebrate species. Four key behavioural traits: activity, boldness, escape response, and foraging (traits all linked tightly to individual fitness) were studied in larvae before and after one week of exposure to a range of effluent dilutions (0, 50, 75, 100%). Effluent exposure reduced activity and foraging, but generated faster escape response. Metabolomic analyses via targeted and non-targeted mass spectrometry methods revealed that exposure caused significant changes to 14 individual compounds (4 amino acids, 3 carnitines, 3 lysolipids, 1 peptide, 2 sugar acids, 1 sugar). Taken together, these compound changes indicate an increase in protein metabolism and oxidative stress. Our findings illustrate that wastewater effluent can affect both behavioural and physiological traits of aquatic invertebrates, and as such might pose an even greater threat to aquatic ecosystems than previously assumed. More long-term studies are now needed evaluate if these changes are linked to adverse effects on fitness. The combination of behavioural and metabolomic assessments provide a promising tool for detecting effects of wastewater effluent, on multiple biological levels of organisation, in aquatic ecosystems.

Effect of magnetization on the adsorptive removal of an emerging contaminant ciprofloxacin by magnetic acid activated carbon

Magnetic acid activated carbons (MAAC) were prepared from the shells of Sterculia villosa Roxb by activating the biomass and magnetizing it using the co-precipitation technique. Characterization of MAAC prior and post adsorption was performed using various microscopic and spectroscopic analytical techniques, and they verified the formation of magnetic aggregates over porous activated carbon surface. Vibrating Sample Magnetometer (VSM) analysis confirmed the superparamagnetic behaviour of the adsorbent with saturation magnetization (Ms) value of 18.2 emu/g, causing an easy and rapid recovery from the adsorption setup in the presence of an external magnetic field. Langmuir isotherm and pseudo-second-order kinetic model best fit the experimental data with theoretical Langmuir maximum adsorption capacity as 81.97 mg/g and verifying chemisorption type of adsorption process, respectively. Thermodynamic analysis verified the interaction among adsorbate and adsorbent as endothermic, spontaneous, and thermodynamically favourable. Co-existing metal cations showed a significant reduction in ciprofloxacin removal efficiency; co-existing anions, though, showed a negligible influence on the adsorption efficiency of MAAC. Recyclability studies verified that the adsorption efficiency fell from 98% in the first cycle to 43% in the fifth cycle. The Ms value fell to 7.6 emu/g (after five adsorption cycles), affecting the adsorbent's recovery. The Phyto-toxicological assessment was performed to evaluate the environmental risk to human and aquatic life using Vigna mungo seeds. MAAC proved to be an effective and magnetically separable adsorbent for removing antibiotics.

Sustainable biochar: A facile strategy for soil and environmental restoration, energy generation, mitigation of global climate change and circular bioeconomy

The increasing agro-demands with the burgeoning population lead to the accumulation of lignocellulosic residues. The practice of burning agri-residues has consequences viz. Release of soot and smoke, nutrient depletion, loss of soil microbial diversity, air pollution and hazardous effects on human health. The utilization of agricultural waste as biomass to synthesize biochar and biofuels, is the pertinent approach for attaining sustainable development goals. Biochar contributes in the improvement of soil properties, carbon sequestration, reducing greenhouse gases (GHG) emission, removal of organic and heavy metal pollutants, production of biofuels, synthesis of useful chemicals and building cementitious materials. The biochar characteristics including surface area, porosity and functional groups vary with the type of biomass consumed in pyrolysis and the control of parameters during the process. The major adsorption mechanisms of biochar involve physical-adsorption, ion-exchange interactions, electrostatic attraction, surface complexation and precipitation. The recent trend of engineered biochar can enhance its surface properties, pH buffering capacity and presence of desired functional groups. This review focuses on the contribution of biochar in attaining sustainable development goals. Hence, it provides a thorough understanding of biochar's importance in enhancing soil productivity, bioremediation of environmental pollutants, carbon negative concretes, mitigation of climate change and generation of bioenergy that amplifies circular bioeconomy, and concomitantly facilitates the fulfilment of the United Nation Sustainable Development Goals. The application of biochar as seen is primarily targeting four important SDGs including clean water and sanitation (SGD6), affordable and clean energy (SDG7), responsible consumption and production (SDG12) and climate action (SDG13).

Quantitatively identifying the emission sources of pharmaceutically active compounds (PhACs) in the surface water: Method development, verification and application in Huangpu River, China

Recognizing the main sources of pharmaceutically active compounds (PhACs) found in surface waters has been a challenge to the effective control of PhAC contamination from the sources. In the present study, a novel method based on Characteristic Matrix (ChaMa) model of indicator PhACs to quantitatively identify the contribution of multiple emission sources was developed, verified, and applied in Huangpu River, Shanghai. Carbamazepine (CBZ), caffeine (CF) and sulfadiazine (SDZ) were proposed as indicators. Their occurrence patterns in the corresponding emission sources and the factor analysis of their composition in the surface water samples were employed to construct the ChaMa model and develop the source apportionment method. Samples from typical emission sources were collected and analyzed as hypothetical surface water samples, to verify the method proposed. The results showed that the calculated contribution proportions of emission sources to the corresponding source samples were 45%-85%, proving the feasibility of the method. Finally, the method was applied to different sections in Huangpu River, and the results showed that livestock wastewater was the dominant emission source, accounting for 55%-73% in the upper reach of Huangpu River. Untreated municipal wastewater was dominant in the middle and lower reaches of Huangpu River, accounting for 76%-94%. This novel source apportionment method allows the quantitative identification of the contribution of multiple PhAC emission sources. It can be replicated in other regions where the occurrence of localized indicators was available, and will be helpful to control the contamination of PhACs in the water environment from the major sources.

Single enrichment systems possibly underestimate both exposures and biological effects of organic pollutants from drinking water

Comprehensive enrichment of contaminants in drinking water is an essential step for accurately determining exposure levels of contaminants and testing their biological effects. Traditional methods using a single absorbent for enriching contaminants in water might not be adequate for complicated matrices with different physical-chemical profiles. To examine this hypothesis, we used an integrated enrichment system that had three sequential stages-XAD-2 resin, poly (styrene-divinylbenzene) and activated charcoal to capture organic pollutants and disinfection by-products (DBPs) from drinking water in Shanghai. Un-adsorbed Organic Compounds in Eluates (UOCEs) named UOCEs-A, -B, and-C following each adsorption stage were determined by gas chromatography-mass spectrometry to evaluate adsorption efficiency of the enrichment system. Meanwhile, biological effects such as cytotoxicity, effects on reactive oxygen species (ROS) generation and glutathione (GSH) depletion were determined in human LO2 cells to identify potential adverse effects on exposure to low dose contaminants. We found that poly-styrene-divinylbenzene (PS-DVB) and activated charcoal (AC) could still partly collect UOCEs-A and-B that the upper adsorption column incompletely captured, and that potential carcinogens like 2-naphthamine were present in all eluates. UOCEs-A at (1-4000), UOCEs-B at (1000-4000), and UOCEs-C at (2400-4000) folds of the actual concentrations had significant cytotoxicity to LO2 cells. Additionally, ROS and GSH change in cells treated with UOCEs indicated the potential for long-term effects of exposure to some mixtures of contaminants such as DBPs at low doses. These results suggested that an enriching system with a single adsorbent would underestimate the exposure level of pollutants and the biological effects of organic pollutants from drinking water. Effective methods for pollutants' enrichment and capture of drinking water should be given priority in future studies on accurate evaluation of biological effects exposed to mixed pollutants via drinking water.

Stable isotope probing reveals specific assimilating bacteria of refractory organic compounds in activated sludge

Activated sludge in wastewater treatment bioreactors contains diverse bacteria, while little is known about the community structure of bacteria responsible for degradation of refractory organic compounds (ROCs). In this study, 10 ROCs frequently detected in sewage were investigated, and the potential bacteria degrading these ROCs were analyzed by DNA stable isotope probing and high-throughput sequencing. The results showed that the bacterial communities responsible for degradation of different ROCs were largely different. A total of 84 bacterial genera were found to be involved in degrading at least one of the 10 ROCs, however, only six genera (Acinetobacter, Bacteroides, Bosea, Brevundimonas, Lactobacillus and Pseudomonas) were common to all 10 ROCs. This suggests that different ROCs may have specific assimilating bacteria in the activated sludge. Our results also showed that these ROC-degrading bacteria are difficult to isolate by conventional methods and that most of them have relatively low relative abundance in municipal wastewater treatment bioreactors. Development of new technologies to increase the abundance and activity of these bacteria may significantly improve the removal efficiency of ROCs from wastewater.

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.

Effective degradation of COVID-19 related drugs by biochar-supported red mud catalyst activated persulfate process: Mechanism and pathway

With the global spread of the COVID-19 pandemic, the water pollution caused by extensive production and application of COVID-19 related drugs has aroused growing attention. Herein, a novel biochar-supported red mud catalyst (RM-BC) containing abundant free hydroxyl groups was synthesized. The RM-BC activated persulfate process was firstly put forward to degrade COVID-19 related drugs, including arbidol (ARB), chloroquine phosphate, hydroxychloroquine sulfate, and acyclovir. Highly effective removal of these pharmaceuticals was achieved and even 100% of ARB was removed within 12 min at optimum conditions. Mechanism study indicated that SO₄ ^•- and HO^• were the predominant radicals, and these radicals were responsible for the formation of DMPOX in electron spin resonance experiments. Fe species (Fe⁰ and Fe₃O₄) and oxygen-containing functional groups in RM-BC played crucial roles in the elimination of ARB. Effects of degradation conditions and several common water matrices were also investigated. Finally, the degradation products of ARB were identified by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and possible degradation pathways were proposed. This study demonstrated that RM-BC/PS system would have great potential for the removal of COVID-19 related drug residues in water by the catalyst synthesized from the solid waste.

Stability and Removal of Benzophenone-Type UV Filters from Water Matrices by Advanced Oxidation Processes

Benzophenone (BP) type UV filters are common environmental contaminants that are posing a growing health concern due to their increasing presence in water. Different studies have evidenced the presence of benzophenones (BP, BP-1, BP-2, BP-3, BP-4, BP-9, HPB) in several environmental matrices, indicating that conventional technologies of water treatment are not able to remove them. It has also been reported that these compounds could be associated with endocrine-disrupting activities, genotoxicity, and reproductive toxicity. This review focuses on the degradation kinetics and mechanisms of benzophenone-type UV filters and their degradation products (DPs) under UV and solar irradiation and in UV-based advanced oxidation processes (AOPs) such as UV/H₂O₂, UV/persulfate, and the Fenton process. The effects of various operating parameters, such as UV irradiation including initial concentrations of H₂O₂, persulfate, and Fe²⁺, on the degradation of tested benzophenones from aqueous matrices, and conditions that allow higher degradation rates to be achieved are presented. Application of nanoparticles such as TiO₂, PbO/TiO₂, and Sb₂O₃/TiO₂ for the photocatalytic degradation of benzophenone-type UV filters was included in this review.

Pharmaceuticals as emerging pollutants: Case naproxen an overview

Nonsteroidal anti-inflammatory drugs (NSAIDs), including naproxen (NP), diclofenac, ibuprofen, etc., are widely used for fever and pain relief. NP is one of the most widely consumed drugs in the world, because it is available over the counter in many countries. Many studies have proven that NP is not eliminated in conventional water treatment processes and its biodegradation in the environment is also difficult compared to other drugs. Along these lines, we are aware that both the original compound and its metabolites can be found in different destinations in the environment. To assess the environmental exposure and the risks associated with NP, it is important to understand better the environment where they finally reach, the behavior of its original compounds, its metabolites, and its transformation products. In this sense, the purpose of this review is to summarize the current state of knowledge about the introduction and behavior of NP in the environments they reach and highlight research needs and gaps. Likewise, we present the sources, environmental destinations, toxicology, environmental effects, and quantification methodologies.

Photodegradation and ozonation of ibuprofen derivatives in the water environment: Kinetics approach and assessment of mineralization and biodegradability

This article presents the results of studies on the degradation of ibuprofen transformation products: 1-hydroxyibuprofen (1OHIBF), 4-ethylbenzaldehyde (4EBA), 1-[4-(2-methylpropyl)phenyl]ethan-1-ol (MPPE) in water. To the best of our knowledge, this is the first paper where the ozonation and photodegradation (VIS and UV photolysis, degradation in H₂O₂/UV system, photosensitized oxidation) of 1OHIBF, 4EBA and MPPE are reported. The processes were performed in demineralized and natural river water. The influence of various reaction parameters on the removal degree was checked. Both, photolysis under VIS light and photosensitized oxidation of target compounds are very low-efficient processes. Ozonation and degradation in H₂O₂/UV system are effective methods for ibuprofen derivatives degradation. Components present in river water reduced removal degree of investigated compounds during ozonation and degradation in H₂O₂/UV system. The biodegradability assessment using the Average Oxidation State (AOS) and COD/TOC ratio proved the formation of more oxidized by-products during both processes. The determined second-order rate constants for ozone reaction with 1OHIBF, 4EBA and MPPE are 0.1 ± 0.01, 10.95 ± 1.36 and 3.04 ± 0.33 M^-1 s^-1, respectively. The calculated reaction rate constants of hydroxyl radicals with MPPE, 4EBA and 1OHIBF are 3.57 × 10⁹, 6.83 × 10⁹ and 1.06 × 10⁹ M^-1 s^-1, respectively.

A recent advancement on nanomaterials for electrochemical sensing of sulfamethaoxole and its futuristic approach

Sulfamethoxazole (SMX) forms the high harmfulness and causing negative health impacts to well-being human and environment that found to be major drastic concern. It is subsequently important to keep in track for monitoring of SMX through convenient detecting devices which include the requirement of being minimal expense and potential for on location environmental applications. Nanomaterials based design has been proposed to determine the SMX antibiotic which in turn provides the solution for this issue. In spite of the critical advancement accomplished in research, further endeavors are yet to foster the progress on electrochemical sensors with the guide of various functional nanomaterials and guarantee the effective transportability for such sensors with improved coherence. Moreover, it has been noticed that, only few reports on electrochemical sensing of SMX detection using nanomaterials was observed. Hence an in-depth evaluation of electrochemical sensing systems using various nanomaterials for SMX detection was summarized in this review. Additionally this current review centers with brief presentation around SMX hazard evaluation followed by study on the current logical techniques to feature the importance for SMX detection. This review will provide the sum up view towards the future ideas of this field which assists in improving the detecting strategies for SMX detection.

Pharmaceuticals and Personal Care Products in the Marine Environment Around False Bay, Cape Town, South Africa: Occurrence and Risk-Assessment Study

Pollution of the marine environment has been increasing as a result of anthropogenic activities. The preservation of marine ecosystems as well as the safety of harvested seafood are nowadays a global concern. In the present study, levels of pharmaceuticals and personal care products were assessed in different environmental compartments in the near-shore marine environment of False Bay, Cape Town, South Africa. The study revealed the presence of these persistent chemical compounds in different environmental samples from this location. Diclofenac was the most dominant compound detected, with higher concentration than the other pharmaceutical compounds, as well as being present in almost all the samples from the different sites (seawater, 3.70-4.18 ng/L; sediment, 92.08-171.89 ng/g dry wt; marine invertebrates, 67.67-780.26 ng/g dry wt; seaweed, 101.50-309.11 ng/g dry wt). The accumulation of pharmaceuticals and personal care products in the different species of organisms reflects the increasing anthropogenic pressure taking place at the sampling sites along the bay, as a result of population growth, resident lifestyle as well as poorly treated sewage effluent discharge from several associated wastewater-treatment plants. The concentration of these contaminants is in the order marine biota > sediments > seawater. The contaminants pose a low acute and chronic risk to the selected trophic levels. A public awareness campaign is needed to reduce the pollution at the source, as well as wastewater discharge limits need to be more stringent. Environ Toxicol Chem 2022;41:614-634. © 2021 SETAC.

Individual and synergic effect of carbamazepine and diclofenac in the removal of organic matter from an expanded granular bed anaerobic reactor

Due to the negative effects caused to the natural environment by the presence of pharmaceutical-type traces and other pollutants in wastewater, it is necessary to develop and optimize efficient treatment systems. This study evaluated the effect of carbamazepine (CBZ) and diclofenac (DCF) on the behavior of seven EGSB (expanded granular sludge bed) anaerobic reactors at laboratory scale, using chromatographic and physicochemical analyses of the influent, effluent, and the biomass contained in the reactors. The results showed that CBZ had a greater effect on the removal and behavior of microorganisms than DCF, with average efficiencies of 34.04 ± 18.58%, 20.76 ± 8.51% and 16.29 ± 11.08% during stage II, III and IV, respectively, for CBZ, and 92.37 ± 12.74%, 26.77 ± 5.90% and 22.28 ± 9.60% during stage II, III and IV, respectively, for DCF. Additionally, it was found that the interaction of the co-substrate used (sodium acetate) in conjunction with the pharmaceutical compounds decreased the efficiency of the system in terms of the removal of analytes.

Electron beam induced degradation of indomethacin in aqueous solution: kinetics, degradation mechanism, and toxicity assessment

Pharmaceutical compounds were emerging contaminants, and the accumulation of pharmaceutical compounds in the environment increased the risk to humans and ecosystems. In this study, electron beam irradiation was applied to degrade indomethacin (IDM) in aqueous solution. IDM degradation followed pseudo-first-order kinetics and 300 μM IDM could be completely degraded at only 2 kGy. According to the quenching experiment, the dose constant ratios of oxidative radicals (•OH) and reductive radicals (e^-aq and •H) could be calculated as k_•OH: k_{e aq and •H}=4.79:1. As the concentration of H₂O₂ increased from 0 to 10 mM, the dose constant increased from 1.883 to 2.582 kGy^-1. However, degradation effect would be restrained in the existence of NO^-₃, NO^-₂, CO^2-₃, HCO^-₃, SO^2-, and humic acid due to their competition for the active species. Theoretical calculation revealed the radical attacking sites of IDM molecule and the most probable pathways were proposed with identification of intermediates. The attack of •OH mainly resulted in the cleavage of amide bond, indole ring opening, demethoxylation, and •OH addition. Dechlorination and the reduction of the carbonyl group occurred on IDM molecular through the reduction of e^-_aq and •H. The intermediates could continue to be degraded to small molecule acid, such as formic acid, acetic acid, and oxalic acid. Furthermore, highly toxic IDM transformed into less toxic products during the irradiation process.

Heat-activated peracetic acid for degradation of diclofenac: kinetics, influencing factors and mechanism

ABSTRACTHeat-activated peracetic acid (PAA) was used to degrade diclofenac (DCF) in this study. Electron paramagnetic resonance and radical scavenging experiments proved that organic radicals (i.e. CH₃C(=O)O• and CH₃C(=O)OO•) were the primary active species for DCF removal in the heat/PAA process. The degradation efficiency of DCF increased with the increase of temperature or initial PAA concentration in the heat/PAA process, and the optimal reaction pH for DCF removal was neutral. The presence of NO₃^- or SO₄^2- insignificantly affected DCF degradation, while Cl^- was favourable for DCF removal in this process. In contrast, an obvious inhibition on the removal of DCF was observed with the addition of natural organic matter, which might be responsible for the lower DCF removal in real waters. Finally, dechlorination, formylation, dehydrogenation and hydroxylation were proposed to be four degradation pathways of DCF in the heat/PAA system based on the five detected transformation products.