Human pharmaceuticals in the aquatic environment: a challenge to Green Chemistry

Adsorptive removal of oxytetracycline hydrochloride using bagasse-based biochar powder and beads

Oxytetracycline Hydrochloride (OTC), a common antibiotic used to treat specific illnesses in humans and animals, is characterized by poor absorption into cells, low volatility, and high hydrophilicity. It is a potent contaminant that poses a serious threat to the ecosystem, particularly the aquatic sources. Adsorption onto natural adsorbents is one of the most successful, economical, and ecologically friendly ways to remove antibiotics from waste water. The present work focuses on the adsorption of OTC utilizing alginate biochar beads (AlBCB) and biochar powder (BC) derived from bagasse. The influence of several factors were studies and optimized through batch studies employing BC and AlBCB. After 50 min BC displayed a removal of 97%, at an initial concentration of 10 ppm. The experimental data was discovered to follow PFO kinetics and fit with the Freundlich isotherm adsorption model. AlBCB, after a contact time of 40 min, indicated a maximum percentage removal of 86% for initial concentration of 10 ppm OTC. Al-biochar beads showed the maximum percentage removal at pH 10. 0.5 g of adsorbent was used to carry out all batch experiments at room temperature. The adsorption fitted Freundlich adsorption isotherm and intraparticle diffusion kinetics.

Quantitative Microbial Risk Assessment of Antibiotic-Resistant E. coli, Legionella pneumophila, and Mycobacteria in Nonpotable Wastewater Reuse Applications

Antibiotic-resistant bacteria (ARB) have become a major threat to public health and modern medicine. A simple death kinetics-based dose-response model (SD-DRM) was incorporated into a quantitative microbial risk assessment (QMRA) to assess the risks of exposure to reclaimed wastewater harboring antibiotic-resistant E. coli, Legionella pneumophila, and Mycobacterium avium for multiple exposure scenarios. The fractions of ARB and trace antibiotics present in the body were incorporated to demonstrate their impact on infection risks. Both ARB and antibiotic susceptible bacteria, ASB, are assumed to have the same dose-response in the absence of antibiotics but behave differently in the presence of residual antibiotics in the body. Annual risk of L. pneumophila infection exceeded the EPA 10-4 pppy (per person per year) benchmark at concentrations in reclaimed water greater than 103-104 CFU/L, depending on parameter variation. Enteropathogenic E. coli infection risks meet the EPA annual benchmark at concentrations around 105-106 total E. coli. The results illustrated that an increase in residual antibiotics from 0 to 40% of the minimum inhibitory concentration (MIC) reduced the risk by about 1 order of magnitude for E. coli but was more likely to result in an untreatable infection.

Contamination status, source analysis and exposure assessments of quinolone antibiotics in the south of Yancheng Coastal Wetland, China

Yancheng coastal wetland, the largest coastal wetland in the west coast of the Pacific Ocean and the margin of the Asian continent, has significant environmental, economic and social effects on local human beings. The extensive contamination and potential risk of quinolone antibiotics (QNs) on local aquaculture and human health are still not clear until now. In this study, 52 surface sediment samples were collected to investigate the contamination status and polluted sources, and evaluate ecological risks of QNs in the south of Yancheng coastal wetland. The total contents of QNs ranged from 0.33 to 21.60 ng/g dw (mean value of 4.51 ng/g dw), following the detection frequencies of QNs ranging from 19.23 to 94.23%. The highest content of QNs occurred around an aquaculture pond dominated by flumequine. The total organic carbon contents of sediment were positively correlated with sarafloxacin and lomefloxacin (p < 0.05), indicating the enhanced absorption of these QNs onto sediments. Partial QNs, such as lomefloxacin, enrofloxacin, sarafloxacin and flumequine, presented the homology features originating from the emission of medical treatment and aquaculture. There was no potential risk of QNs to human beings but a potential risk to aquatic organisms (algae > plant > invertebrate). Totally, the management and protection of Yancheng coastal wetland should be of concern with aquaculture as the important industry.

A new biphenol-dipicolylamine based ligand and its dinuclear Zn2+ complex as fluorescent sensors for ibuprofen and ketoprofen in aqueous solution

In this work, the study of the new ligand 3,3'-bis[N,N-bis(pyridine-2-ylmethyl)aminomethyl]-2,2'-dihydroxybiphenyl (L) is reported, where a central 2,2'-biphenol (BPH) fluorophore was functionalized at 3,3'-positions with two dipicolylamine (DPA) side arms as receptor units. Following the synthesis and full chemical-physical characterization, the acid-base and Zn2+-coordination abilities of L were investigated through a combination of potentiometric, UV-Vis, fluorescence, NMR, XRD and DFT measurements. The optical properties of the ligand turned out to be strongly dependent on the pH, being straightforwardly associated with the protonation state of the BPH moiety, whereas its peculiar design allowed to form stable mono and dinuclear Zn2+ complexes. In the latter species, the presence of two Zn2+ ions coordinatively unsaturated and placed at close distance to each other, prompted us to test their usefulness as metallo-receptors for two environmental pollutants of great relevance, ibuprofen and ketoprofen. Potentiometric and fluorescence investigations evidenced that these important non-steroidal anti-inflammatory drugs (NSAIDs) are effectively coordinated by the metallo-receptors and, of relevance, both the stability and the fluorescence properties of the resulting ternary adducts are markedly affected by the different chemical architectures of the two substrates. This study aims at highlighting the promising perspectives arising from the use of polyamino phenolic ligands as chemosensors for H+/Zn2+ and other additional anionic targets in their metal-complexed forms.

Recent advances in photocatalytic removal of antiviral drugs by Z-scheme and S-scheme heterojunction

The possible impact of antivirals on ecosystems and the emergence of antiviral resistance are the reasons for concern about their environmental release. Consequently, there has been a significant increase in curiosity regarding their presence in both organic and synthetic systems in recent years. The primary objective of this review is to address the void of information regarding the global presence of antiviral drugs in both wastewater and natural water sources. Photocatalytic degradation of pollutants is an eco-friendly, cost-effective method that effectively addresses environmental degradation. The development of efficient photocatalysts remains a significant issue in accelerating the degradation of pollutants, especially when employing solar light. Thus, the development of Z-scheme and S-scheme semiconductor heterojunctions has emerged as a viable method to improve light absorption and enhance the redox capability of photocatalysts. The principles of Z-scheme and S-scheme are reviewed extensively. The degradation route and occurrence of antiviral are discussed briefly. Finally, a short preview of the degradation of antiviral using Z-scheme and S-scheme is also highlighted.

Impact of the rearing environment on the metabolism of shrimps and tracing the origins and species of shrimps using specific metabolites

Herein, the link between rearing environmental condition and metabolism was explored. Metabolite fingerprint datasets of black tiger shrimp (Penaeus monodon) from three production sites were collected and studied using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) and HPLC-MS/MS. Two compounds, benzisothiazolinone and hippuric acid, were identified to be potentially related to pollution in the rearing environment and showed different abundances in the analysed shrimp samples with different origins. Furthermore, metabolomic analysis on three shrimp species, black tiger shrimp, kuruma shrimp (Penaeus japonicus) and sword shrimp (Parapenaeopsis hardwickii), under an identical rearing environment was also conducted. Two compounds, diethanolamine and benzisothiazolinone, potentially linked with pollution in the rearing environment were identified. The present protocol holds promise to be extended to the studies of exploring the relationship between rearing environmental conditions and metabolism. Furthermore, the analysis of single-blind samples was conducted. The results show that specific metabolites can be utilized as markers for tracing the origins of shrimp samples. The present protocol holds potential for application in tracing the origin and species of certain seafoods.

Geopolymer-Based Materials for the Removal of Ibuprofen: A Preliminary Study

Every year, new compounds contained in consumer products, such as detergents, paints, products for personal hygiene, and drugs for human and veterinary use, are identified in wastewater and are added to the list of molecules that need monitoring. These compounds are indicated with the term emerging contaminants (or Contaminants of Emerging Concern, CECs) since they are potentially dangerous for the environment and human health. To date, among the most widely used methodologies for the removal of CECs from the aquatic environment, adsorption processes play a role of primary importance, as they have proven to be characterized by high removal efficiency, low operating and management costs, and an absence of undesirable by-products. In this paper, the adsorption of ibuprofen (IBU), a nonsteroidal anti-inflammatory drug widely used for treating inflammation or pain, was performed for the first time using two different types of geopolymer-based materials, i.e., a metakaolin-based (GMK) and an organic-inorganic hybrid (GMK-S) geopolymer. The proposed adsorbing matrices are characterized by a low environmental footprint and have been easily obtained as powders or as highly porous filters by direct foaming operated directly into the adsorption column. Preliminary results demonstrated that these materials can be effectively used for the removal of ibuprofen from contaminated water (showing a concentration decrease of IBU up to about 29% in batch, while an IBU removal percentage of about 90% has been reached in continuous), thus suggesting their potential practical application.

Environmental risk assessment of selected pharmaceuticals in hospital wastewater in nothern Vietnam

Pharmaceuticals are progressively employed in both human and veterinary medicine and increasingly recognized as environmental contaminants. This study investigated the occurrence of selected pharmaceuticals in influent and effluent of wastewater treatment plants of 12 hospitals in Hanoi and 3 northern cities of Vietnam during dry and rainy seasons. In addition, environmental risk of pharmaceuticals in both hospital influents and effluents were evaluated based on risk quotients (RQs). Nine selected pharmaceutical compounds including sulfamethoxazole (SMX), naproxen (NPX), diclofenac (DCF), ibuprofen (IBU), acetaminophen (ACT), carbamazepine (CBM), iopromide (IOP), atenolol (ATN), and caffeine (CAF) were frequently detected in most influent and effluent wastewaters of 12 investigated hospitals. Detected compound levels exhibited a wide range, from as low as 1 ng/L for DCF to as high as 61,772 ng/L for ACT. Among these compounds, ACT, CAF, SMX, and IOP were consistently detected at substantial concentrations in both influents and effluents. This investigation also highlighted potential risks posed by SMX, ACT, and CAF residues present in influents and effluents of hospital wastewater treatment plants (WWTPs) to aquatic ecosystem. These finding are expected to provide scientific-based evidence for the development of hospital waste management and environmental management programs in Vietnam.

Assessment of new hydrogen peroxide activators in water and comparison of their active species toward contaminants of emerging concern

Advanced oxidation processes are the most efficient tool to thwart the overaccumulation of harmful organic compounds in the environment. In this direction bioinspired metal complexes may be a viable solution for oxidative degradations in water. However, their synthesis is often elaborated and their scalability consequently low. This study presents alternative easy-to-synthesize bioinspired metal complexes to promote degradations in water. The metals employed were iron and manganese ions, hence cheap and highly accessible ions. The complexes were tested toward Phenol, Estrone, Triclosan, Oxybenzone, Diclofenac, Carbamazepine, Erythromycin, Aspartame, Acesulfame K, Anisole and 2,4-Dinitrotoluene. The reaction favoured electron-rich compounds reaching a removal efficiency of over 90%. The central ion plays a crucial role. Specifically, Mn(II) induces a non-radical pathway while iron ions a predominant radical one (⋅OH is predominant). The iron systems resulted more versatile toward contaminants, while the manganese ones showed a higher turn-over number, hence higher catalytic behaviour.

A sustainable activated carbon fiber/TiO2 cathode for the photoelectro-Fenton treatment of pharmaceutical pollutant enalapril

In this work, a TiO2-decorated electrode was fabricated by dip coating activated carbon fibers (ACF) with TiO2, which were then used as a cathode for the photoelectro-Fenton (PEF) treatment of the pharmaceutical enalapril, an angiotensin-converting enzyme inhibitor that has been detected in several waterways. The TiO2 coating was found to principally improve the electrocatalytic properties of ACF for H2O2 production via the 2-e- O2 reduction, in turn increasing enalapril degradation by PEF. The effect of the current density on the mineralization of enalapril was evaluated and the highest TOC removal yield (80.5% in 3 h) was obtained at 8.33 mA cm-2, in the presence of 0.5 mmol L-1 of Fe2+ catalyst. Under those conditions, enalapril was totally removed within the first 10 min of treatment with a rate constant k = 0.472 min-1. In contrast, uncoated ACF only achieved 60% of TOC removal in 3 h at 8.33 mA cm-2. A degradation pathway for enalapril mineralization is proposed, based on the degradation by-products identified during treatment. Overall, the results demonstrate the promises of TiO2 cathodes for PEF, a strategy that has often been overlooked in favor of photoelectrocatalysis (PEC) based on TiO2-modified photoanodes.

Effects of a TAML catalyst on mice exposed during pregnancy and lactation

Tetra-amido macrocyclic ligands (TAMLs) are catalysts designed to mimic endogenous peroxidases that can degrade pollutants. Before TAMLs gain widespread use, it is first important to determine if they have endocrine disrupting properties. In this study, we evaluated the effects of the iron TAML, NT7, on hormone-sensitive outcomes in mice exposed during pregnancy and lactation, and on their litters prior to weaning. We administered NT7 at one of three doses to mice via drinking water prior to and then throughout pregnancy and lactation. Two hormonally active pharmaceuticals, ethinyl estradiol (EE2) and flutamide (FLUT), a known estrogen receptor agonist and androgen receptor antagonist, respectively, were also included. In the females, we measured pre- and post-parturition weight, length of pregnancy, organ weights at necropsy, and morphology of the mammary gland at the end of the lactational period. We also quantified maternal behaviors at three stages of lactation. For the offspring, we measured litter size, litter weights, and the achievement of other developmental milestones. We observed only one statistically significant effect of NT7, a decrease in the percentage of pups with ear opening at postnatal day 5. This contrasts with the numerous effects of EE2 on both the mother and the litter, as well as several modest effects of FLUT. The approach taken in this study could provide guidance for future studies that aim to evaluate novel compounds for endocrine disrupting properties.

Antibiotics and antibiotic resistance genes removal in biological aerated filter

Two laboratory-level biological aerated filters (BAF) were constructed to explore their treatment capacity for simulated antibiotic wastewater at high (1 - 16 mg/L) and low (0 - 0.5 mg/L) concentrations. Results showed that BAF was capable of removing both sulfonamides and tetracyclines with an efficiency of over 90 % at 16 mg/L. The main mechanism for removing antibiotics was found to be biodegradation followed by adsorption. Paenarthrobacter was identified as the key genus in sulfonamides degradation, while Hydrogenophaga played a crucial role in tetracyclines degradation. Antibiotics resistant genes such as intI1, sul1, sul2, tetA, tetW and tetX were frequently detected in the effluent, with interception rates ranging from 105 - 106 copies/mL. The dominated microorganisms obtained in the study could potentially be utilized to enhance the capacity of biological processes for treating antibiotics contaminated wastewater. These findings contribute to a better understanding of BAF treating wastewater containing antibiotics and resistant genes.

Efficient treatment of veterinary pharmaceutical industrial wastewater by catalytic ozonation process: degradation of enrofloxacin via molecular ozone reactions

The study focused on the efficacious performance of bimetallic Fe-Zn loaded 3A zeolite in catalytic ozonation for the degradation of highly toxic veterinary antibiotic enrofloxacin in wastewater of the pharmaceutical industry. Batch experiments were conducted in a glass reactor containing a submerged pump holding catalyst pellets at suction. The submerged pump provided the agitation and recirculation across the solution for effective contact with the catalyst. The effect of ozone flow (0.8-1.55 mg/min) and catalyst dose (5-15 g/L) on the enrofloxacin degradation and removal of other conventional pollutants COD, BOD5, turbidity was studied. In batch experiments, 10 g of Fe-Zn 3A zeolite efficiently removed 92% of enrofloxacin, 77% of COD, 69% BOD5, and 61% turbidity in 1 L sample of pharmaceutical wastewater in 30 min at 1.1 mg/min of O3 flow. The catalytic performance of Fe-Zn 3A zeolite notably exceeded the removal efficiencies of 52%, 51%, 52%, and 59% for enrofloxacin, COD, BOD5, and turbidity, respectively, achieved with single ozonation process. Furthermore, an increase in the biodegradability of treated pharmaceutical industrial wastewater was observed and made biodegradable easily for subsequent treatment.

Selected widely prescribed pharmaceuticals: toxicity of the drugs and the products of their photochemical degradation to aquatic organisms

Cholesterol-lowering drugs, antidiabetics, antiarrhythmics, antidepressants, and antibiotics belong to the most prescribed drugs worldwide. Because of the manufacture, excretion, and improper disposal of leftover drugs, the drugs enter waste waters and, subsequently, surface waters. They have been detected in surface waters all over the world, from concentrations of ng/l to concentrations several orders of magnitude higher. Since pharmaceuticals are designed to be both biologically and chemically stable, photochemical degradation by sun radiation represents a way of transformation in the natural environment. This review provides a survey of how selected drugs of the above-mentioned classes affect aquatic organisms of different trophic level. The emphasis is on the harmful effects of phototransformation products, an area of scientific investigation that has only attracted attention in the past few years, revealing the surprising fact that products of photochemical degradation might be even more toxic to aquatic organisms than the parent drugs.

Graphite/carbon-doped TiO2 nanocomposite synthesized by ultrasound for the degradation of diclofenac

Graphite/C-doped TiO2 nanocomposite was synthesized at room temperature using a simple, impressive, and indirect sonication (20 kHz) by the cup horn system. Tetrabutyltitanate as the precursor of titanium and graphite (G) as the carbon source was used in the preparation of nanocomposite as a photocatalyst. The molar ratio of G/TiO2 as a key parameter was investigated in the synthesis of G/C-doped TiO2. The obtained materials were widely characterized using XRD, SEM, TEM, FTIR, XPS, and UV-Vis diffuse reflectance techniques. The UV-Vis diffuse reflectance spectroscopy results showed that the edge of light absorption of nanocomposite was distinctly red-shifted to the visible area via carbon doping. The XPS outcomes acknowledged the existence of the C, Ti, and O in the photocatalyst. The composite showed an enhancement in the dissociation efficiency of photoinduced charge carriers through the doping process. The photocatalytic activity of the synthesized nanocomposite was checked with diclofenac (DCF) as a pharmaceutical contaminant. The results displayed that G/C-doped TiO2 represented better photocatalytic performance for DCF than TiO2. This was due to the excellent crystallization, intense absorption of visible light, and the impressive separation of photoinduced charge carriers. Various active species such as •OH, •O2¯, h+, and H2O2 play a role in the degradation of DFC. Therefore, different scavengers were used and the role of each one in degradation was investigated. According to the obtained results, •O2¯ radical showed a major role in the photocatalytic process. This work not only proposes a deep insight into the photosensitization-like mechanism by using G-based materials but also develops new photocatalysts for the removal of emerging organic pollutants from waters using sunlight as available cheap energy.

o-Semiquinone Radical and o-Benzoquinone Selectively Degrade Aniline Contaminants in the Periodate-Mediated Advanced Oxidation Process

Advanced oxidation processes (AOPs) often employ strong oxidizing inorganic radicals (e.g., hydroxyl and sulfate radicals) to oxidize contaminants in water treatment. However, the water matrix could scavenge the strong oxidizing radicals, significantly deteriorating the treatment efficiency. Here, we report a periodate/catechol process in which reactive quinone species (RQS) including the o-semiquinone radical (o-SQ•-) and o-benzoquinone (o-Q) were dominant to effectively degrade anilines within 60 s. The second-order reaction rate constants of o-SQ•- and o-Q with aniline were determined to be 1.0 × 108 and 4.0 × 103 M-1 s-1, respectively, at pH 7.0, which accounted for 21% and 79% of the degradation of aniline with a periodate-to-catechol molar ratio of 1:1. The major byproducts were generated via addition or polymerization. The RQS-based process exhibited excellent anti-interference performance in the degradation of aniline-containing contaminants in real water samples in the presence of diverse inorganic ions and organics. Subsequently, we extended the RQS-based process by employing tea extract and dissolved organic matter as catechol replacements as well as metal ions [e.g., Fe(III) or Cu(II)] as periodate replacements, which also exhibited good performance in aniline degradation. This study provides a novel strategy to develop RQS-based AOPs for the highly selective degradation of aniline-containing emerging contaminants.

Adsorption of Levofloxacin onto Graphene Oxide/Chitosan Composite Aerogel Microspheres

The removal of pharmaceutical residues from water resources using bio-based materials is very important for human safety and health. Bio-based graphene oxide/chitosan (GO/CS) aerogel microspheres were fabricated with emulsification and cross-linking, followed by freeze drying, and were used for the adsorption of levofloxacin (LOF). The obtained GO/CS aerogel microspheres were characterized with scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and thermogravimetry (TG). The effects of GO content, pH value, and temperature on their adsorption capacity were investigated. With the incorporation of 40 wt% GO, the adsorption capacity increased from 9.9 to 45.6 mg/g, and the highest adsorption capacity, 51.5 mg/g, was obtained at pH = 8 and T = 25 °C. In addition, to obtain deeper insight into the adsorption process, the thermodynamics and kinetics of the process were also investigated with four different models of LOF adsorption. The thermodynamic modeling results revealed that LOF adsorption is exothermic, and the kinetic investigation demonstrated that LOF adsorption is generally consistent with a pseudo-first-order rate law.

Tunnel vision in the drinking water research field - Time for non-targeted analysis implementation?

A plethora of compounds can reach our drinking water and possibly affect human health. Still, mostly notorious pollutants like pesticides and disinfection by-products are monitored and regulated. With the increasing availability of high-resolution mass spectrometers (HRMS), non-targeted analyses of environmental samples have become possible. Pilot studies demonstrating the applicability of this approach in the drinking water research field were published. We would like to highlight these studies and appeal to researchers focused on water quality to better exploit the potential of HRMS instruments and broaden the scale of studied pollutants. In addition, the data and experience should be further shared, and the quality standard for the analytical procedures should be set. With advanced knowledge of compounds reaching the drinking water, potential threats would be revealed, and the comprehensive results on water pollution might also act as impulses for associated research branches, including toxicity assessment or development of water treatment technologies, and/or for policy-making.

Effects of perinatal exposures to a TAML catalyst on the mammary gland and hormone-sensitive outcomes in male mice

Estrogenic chemicals are common pollutants in wastewater and current effluent treatment processes are not typically effective in removing these compounds. Tetra-amido macrocyclic ligands (TAMLs) are catalysts that mimic endogenous peroxidases that may provide a solution to remove environmental pollutants including low concentrations of estrogenic compounds. Yet relatively little is known about the toxicity of TAMLs, and few studies have evaluated whether they may have endocrine disrupting properties. We administered one of three doses of a TAML, NT7, to mice via drinking water throughout pregnancy and lactation. Two pharmacologically active compounds, ethinyl estradiol (EE2) and flutamide were also included to give comparator data for estrogen receptor agonist and androgen receptor antagonist activities. Male pups were evaluated for several outcomes at weaning, puberty, and early adulthood. We found that EE2 exposures during gestation and the perinatal period induced numerous effects that were observed across the three ages including changes to spleen and testis weight and drastic effects on the morphology of the mammary gland. Flutamide had fewer effects but altered anogenital distance at weaning as well as spleen, liver, and kidney weight. In contrast, relatively few effects of NT7 were observed, but included alterations to spleen weight and modest changes to adult testis weight and morphology of the mammary gland at weaning. Collectively, these results provide some of the first evidence suggesting that NT7 may alter some hormone-sensitive outcomes, but that the effects were distinct from either EE2 or flutamide. Additional studies are needed to characterize the biological activity of this and other TAML catalysts.

Cu2+ coordination-induced in situ photo-to-heat on catalytic sites to hydrolyze β-lactam antibiotics pollutants in waters

For degradation of β-lactam antibiotics pollution in waters, the strained β-lactam ring is the most toxic and resistant moiety to biodegrade and redox-chemically treat among their functional groups. Hydrolytically opening β-lactam ring with Lewis acid catalysts has long been recognized as a shortcut, but at room temperature, such hydrolysis is too slow to be deployed. Here, we found when Cu2+ was immobilized on imine-linked COF (covalent organic framework) (Cu2+/Py-Bpy-COF, Cu2+ load is 1.43 wt%), as-prepared composite can utilize the light irradiation (wavelength range simulated sunlight) to in situ heat anchored Cu2+ Lewis acid sites through an excellent photothermal conversion to open the β-lactam ring followed by a desired full-decarboxylation of hydrolysates. Under 1 W/cm2 simulated sunlight, Cu2+/Py-Bpy-COF powders placed in a microfiltration membrane rapidly cause a temperature rising even to ~211.7 °C in 1 min. It can effectively hydrolyze common β-lactam antibiotics in waters and even antibiotics concentration is as high as 1 mM and it takes less than 10 min. Such photo-heating hydrolysis rate is ~24 times as high as under dark and ~2 times as high as Cu2+ homogenous catalysis. Our strategy significantly decreases the interference from generally coexisting common organics in waters and potential toxicity concerns of residual carboxyl groups in hydrolysates and opens up an accessible way for the settlement of β-lactam antibiotics pollutants by the only energy source available, the sunlight.

Electrocatalytic Deep Dehalogenation and Mineralization of Florfenicol: Synergy of Atomic Hydrogen Reduction and Hydroxyl Radical Oxidation over Bifunctional Cathode Catalyst

It is difficult to achieve deep dehalogenation or mineralization for halogenated antibiotics using traditional reduction or oxidation processes, posing the risk of microbial activity inhibition and bacterial resistance. Herein, an efficient electrocatalytic process coupling atomic hydrogen (H*) reduction with hydroxyl radical (•OH) oxidation on a bifunctional cathode catalyst is developed for the deep dehalogenation and mineralization of florfenicol (FLO). Atomically dispersed NiFe bimetallic catalyst on nitrogen-doped carbon as a bifunctional cathode catalyst can simultaneously generate H* and •OH through H2O/H+ reduction and O2 reduction, respectively. The H* performs nucleophilic hydro-dehalogenation, and the •OH performs electrophilic oxidization of the carbon skeleton. The experimental results and theoretical calculations indicate that reductive dehalogenation and oxidative mineralization processes can promote each other mutually, showing an effect of 1 + 1 > 2. 100% removal, 100% dechlorination, 70.8% defluorination, and 65.1% total organic carbon removal for FLO are achieved within 20 min (C0 = 20 mg·L-1, -0.5 V vs SCE, pH 7). The relative abundance of the FLO resistance gene can be significantly reduced in the subsequent biodegradation system. This study demonstrates that the synergy of reduction dehalogenation and oxidation degradation can achieve the deep removal of refractory halogenated organic contaminants.

Sequential anodic oxidation and cathodic electro-Fenton in the Janus electrified membrane for reagent-free degradation of pollutants

Electrified membrane technologies have recently demonstrated high potential in tackling water pollution, yet their practical applications are challenged by relying on large precursor doses. Here, we developed a Janus porous membrane (JPEM) with synergic direct oxidation by Magnéli phase Ti4O7 anode and electro-Fenton reactions by CuFe2O4 cathode. Organic pollutants were first directly oxidized on the Ti4O7 anode, where the extracted electrons from pollutants were transported to the cathode for electro-Fenton production of hydroxyl radical (·OH). The cathodic ·OH further enhanced the mineralization of organic pollutant degradation intermediates. With the sequential anodic and cathodic oxidation processes, the reagent-free JPEM showed competitive performance in rapid degradation (removal rate of 0.417 mg L-1 s-1) and mineralization (68.7 % decrease in TOC) of sulfamethoxazole. The JPEM system displayed general performance to remove phenol, carbamazepine, and perfluorooctanoic acid. The JPEM runs solely on electricity and oxygen that is comparable to that of PEM relies on large precursor doses and, therefore, operation friendly and environmental sustainability. The high pollutant removal and mineralization achieved by rational design of the reaction processes sheds light on a new approach for constructing an efficient electrified membrane.

Environmental Sample Stability for Pharmaceutical Compound Analysis: Handling and Preservation Recommendations

Efficient and resilient techniques for handling samples are essential for detecting pharmaceutical compounds in the environment. This study explores a method for preserving water samples during transport before quantitative analysis. The study investigates the stability of 17α-ethynylestradiol (EE2), acetaminophen (ACM), oxytetracycline (OTC), sulfamethoxazole (SMX), and trimethoprim (TMP) after preconcentration within solid-phase extraction (SPE) cartridges. Through various experiments involving different holding times and storage temperatures, it was determined that four pharmaceutical compounds remained stable when stored for a month at 4°C and for six months when stored at -18°C in darkness. Storing these compounds in SPE cartridges at -18°C seemed effective in preserving them for extended periods. In addition, ACM, TMP, OTC, EE2, and SMX remained stable for three days at room temperature. These findings establish guidelines for appropriate storage and handling practices of pharmaceutical compounds preconcentrated from aqueous environmental samples using SPE.

Limitations of conventional approaches to identify photochemically produced reactive intermediates involved in contaminant indirect photodegradation

Dissolved organic matter (DOM) mediated indirect photodegradation can play an important role in the degradation of aquatic contaminants. Predicting the rate of this process requires knowledge of the photochemically produced reactive intermediates (PPRI) that react with the compound of interest, as well as the ability of individual DOM samples to produce PPRI. Key PPRI are typically identified using quencher studies, yet this approach often leads to results that are difficult to interpret. In this work, we analyze the indirect photodegradation of atorvastatin, carbamazepine, sulfadiazine, and benzotriazole using a diverse set of 48 waters from natural and engineered aquatic systems. We use this large data set to evaluate relationships between PPRI formation and indirect photodegradation rate constants, which are directly compared to results using standard quenching experiments. These data demonstrate that triplet state DOM (3DOM) and singlet oxygen (1O2) are critical PPRI for atorvastatin, carbamazepine, and sulfadiazine, while hydroxyl radical (˙OH) contributes to the indirect photodegradation of benzotriazole. We caution against relying on quenching studies because quenching of 3DOM limits the formation of 1O2 and all studied quenchers react with ˙OH. Furthermore, we show that DOM composition directly influences indirect photodegradation and that low molecular weight, microbial-like DOM is positively correlated with the indirect photodegradation rates of carbamazepine, sulfadiazine, and benzotriazole.

Multifunctional Cu:ZnS quantum dots for degradation of Amoxicillin and Dye Sulphon Fast Black-F and efficient determination of urea for assessing environmental aspects

This work is particularly aimed at the preparation of ZnS and Cu doped ZnS (Cu:ZnS) QDs by facile and easy technique, chemical precipitation method for the degradation of water pollutants and a simple scheme was proposed to prepare the urea-sensing system. The morphological and optical properties of the synthesized QDs was studied using high resolution transmission and scanning electron microscopes, X-ray diffraction, energy dispersive X-ray analysis, fluorescence and ultraviolet-visible spectroscopy, differential thermal and thermogravimetric analyses, Brunauer-Emmett-Teller analysis. The photocatalytic performance was systematically assessed by the photodegradation of an important pharmaceutical water pollutant, Amoxicillin (AMX) and a dye Fast Sulphon Black F (SFBF) in aqueous medium under UV light irradiation. Also, a very sensitive system was prepared by depositing the dots over an indium-tin-oxide (ITO) glass substrate for the sensing of biologically active molecule urea as it is an important monitor of public health in water and soil productivity. The results illustrated excellent photocatalytic efficiency (86.46% for AMX and 99.41% for SFBF) with stability up to four cycles of degradation reaction. The optimal photocatalyst dosage for achieving maximum removal of AMX was found to be 70 mg at a pH of 9.5, with a treatment time of 40 min. Similarly, for SFBF, the optimal photocatalyst dosage was determined to be 60 mg at pH 9, with a treatment time of 60 min. Further, the electrochemical analysis was done by fabricating Urease enzyme (UR)/Cu:ZnS QDs/ITO bioelectrode and then the fabricated bioelectrode, was utilized to determine the different concentrations of urea by cyclic voltammetry. Thus, the obtained limit of detection and sensitivity of the fabricated biosensing device for urea detection was obtained to be 0.0092 μM and 12 μA μM-1cm-2, respectively; under the optimized experimental conditions. Hence, it is anticipated that Cu:ZnS QDs can also successfully be applied as a promising material for fabrication of novel bioelectrode for urea determination and the biosensing platform is desirable and viable.

Photodegradable antimicrobial agents: towards structure optimization

Antibiotic resistance continues to be an ominous threat facing human health globally and urgent action is required to limit the loss of human life. The pollution of antibiotics into the environment is one of the drivers behind the crisis. With this in mind, we have developed novel photodecomposable antimicrobial agents based on an ethanolamine scaffold, which upon photoirradiation decomposes into two major inactive fragments. Herein we describe our further work on the synthesis of novel ethanolamines with a particular focus on structure activity relationship, resulting in four new active compounds which photodecomposed into inactive fragments.

Electrochemiluminescence Sensor with Controlled-Release Triggering Electrostatic Attraction Elimination Mechanism for Trenbolone Trace Detection

A controlled-release strategy can meet the needs of sensitive environmental monitoring for pollutants through a self-on/off mode. In this work, an electrochemiluminescence (ECL) biosensor with controlled-release triggering electrostatic attraction elimination and biomolecular stimulated response strategies was constructed to detect environmental steroid hormones sensitively. The blocked pores on the aminated mesoporous silica nanocontainers were opened by specific binding between the trenbolone (TB) antigen and the antibody. The released l-cysteine counteracted the negative charge on the MnO2 NF surface through the redox reaction between -SH and MnO2, making the electrostatic interaction between the MnO2 NFs and the Ru(dcbpy)32+ disappear. Ru(dcbpy)32+ released an ECL signal on the electrode, thus completing the controlled-release triggering electrostatic attraction elimination strategy. In addition, with the TB antibody as the target and the competition strategy between the TB antigen and the standard substance, the constructed controlled-release ECL biosensor was used to detect the TB standard substance. Moreover, MnO2 NFs as the substrate of the ECL biosensor increased the active specific surface area of the electrode, effectively catalyzing the production of OH• and O2•-, thus endowing the ECL biosensor with coreactant-catalytic enhancement characteristic and further improving its ECL performance. This sensitive signal response brought about a low limit of detection of 2.53 fg/mL for the constructed ECL biosensor, which contributed a feasible idea for efficient trace analysis of pollutants in the environment.

Escherichia coli Phylogenetic and Antimicrobial Pattern as an Indicator of Anthropogenic Impact on Threatened Freshwater Mussels

Freshwater bivalves are widely used as accumulation indicators and monitoring tools for assessing contaminant effects on different levels of biological integration. This pilot study aimed to explore the phylogenetic diversity of Escherichia coli isolated from freshwater mussels (Margaritifera margaritifera and Potomida littoralis) and characterize their phenotypes and antibiotic resistance profiles. Samples were collected in the Rabaçal and Tua Rivers, in the Douro basin, Portugal-two sites representing different levels of anthropogenic contamination. Antimicrobial susceptibility testing was performed via the disk diffusion method with 21 antibiotics. Results showed that 31% of isolates were multidrug-resistant (MDR). Thus, freshwater mussels provide an effective and time-integrated approach for identifying/quantifying fecal indicators, including MDR bacteria. PCR-based assays were designed for assessing phylogenetic E. coli groups. Among the E. coli isolates, the highest prevalence (44%) was observed in group D or E, followed by group E or Clade I (25%), group A (19%), and group B1 (13%). E. coli isolated from M. margaritifera predominantly exhibited a higher prevalence of phylogroups D or E, whereas E. coli from P. littoralis showed associations with phylogroups E or clade I, B1, A, and D or E. Our results provide new insights into the phylogenetic diversity of E. coli in freshwater bivalves. Additionally, the findings highlight the possible linkage of phylogroups with the host species, the geographical location in the water stream, and human activity. Using E. coli as a bioindicator isolated from freshwater mussels helps us grasp how human activities affect the environment. This study has important implications for those interested in safeguarding water resources, especially in tackling antibiotic resistance in aquatic ecosystems.

Stakeholders' perspectives and use of web-based knowledge support for environmental information on pharmaceuticals

Background

Pharmaceuticals treat and prevent diseases but can pose a risk to organisms, predominantly in aquatic environments. The use of pharmaceuticals is predicted to increase due to, among other factors, a growing and aging population and climate change. Therefore, it is important to develop mitigation strategies to prevent pharmaceutical residues from entering the environment. In Sweden, two public pharmaceutical web-based knowledge supports provide information on the environmental impact of pharmaceuticals.

Objective

To explore stakeholder perspectives, use and future opportunities related to two webbased knowledge supports publicizing environmental information on pharmaceuticals.

Methods

Stakeholders identified for their experience with the knowledge supports, pharmaceutical policy, and stakeholder collaboration were recruited using purposive and snowball sampling for semi-structured interviews. Interviews were conducted in person or via video calls. Respondents included twenty-one representatives from the pharmaceutical industry, regional and national authorities, academia, and an independent research institute. Interview transcripts were analyzed using content analysis.

Results

Respondents valued having environmental information on pharmaceuticals publicly accessible on two well-known pharmaceutical knowledge supports. The knowledge supports have been used in Sweden and internationally. Perceived differences were recognized between the impact and perspectives of the two knowledge supports with a general preference for the Janusinfo knowledge support. The preference was especially identified regarding transparency and the use of the information in clinical practice. Barriers to impact were a lack of resources and decision-making criteria. Respondents believed that the impact and value of the knowledge supports could be improved with more authority involvement.

Conclusion

Public knowledge support providing environmental information on pharmaceuticals has been valuable across sectors, especially, among Drug and Therapeutics Committees. We believe the results from this study could be useful for other countries interested in implementing a similar system.

Analysis on the attenuation characteristics of PPCPs in surface water and their influencing factors based on a compilation of literature data

The attenuation characteristics of PPCPs play an important part in predicting their environmental concentrations. However, considerable uncertainty remains in reported laboratory data on the attenuation characteristics of PPCPs. In this analysis, we compile information on laboratory-observed photodegradation half-lives (t1/2), biodegradation t1/2, the organic carbon normalized adsorption constant (KOC) and field-observed overall attenuation t1/2 for PPCPs in water bodies from more than 200 peer-reviewed studies. To mitigate the effects of such uncertainty, we derive representative values (RV) for PPCP degradability from these records to better compare the characteristics of different PPCPs. We further examine the influence of experimental conditions and environmental drivers on the determination of t1/2 using difference analysis and correlation analysis. The results indicate that for laboratory photodegradation tests, different light sources, initial concentration and volume significantly affect t1/2, whereas there is no significant difference between values obtained from tests conducted in pure water and natural water. For biodegradation, laboratory-measured t1/2 values in batch, flume and column studies gradually decrease, marking the controlling role of experimental setup. Redox condition, initial concentration and volume are also recognized as important influencing factors. For adsorption, water-sediment ratio is the primary reaction parameter. As two frequently investigated factors, however, pH and temperature are not significant factors in almost all cases. In field observations, the persistence of carbamazepine, typically used as a tracer, is in doubt. Water depth and latitude are the most correlated drivers of t1/2, indicating the predominant status of photodegradation in the overall attenuation rates. These findings call for caution when selecting experimental parameters and environmental drivers in determining PPCP's attenuation rates and establishing PPCP fate models in the field.

Advancements in electrochemical technologies for the removal of fluoroquinolone antibiotics in wastewater: A review

In recent times, the need to make water safer and cleaner through the elimination of recalcitrant pharmaceutical residues has been the aim of many studies. Fluoroquinolone antibiotics such as ciprofloxacin, norfloxacin, enrofloxacin, and levofloxacin are among the commonly detected pharmaceuticals in wastewater. Since the presence of these pharmaceuticals in water bodies poses serious risks to living organisms, it is vital to adopt effective wastewater treatment techniques for their complete removal. Electrochemical technologies such as photoelectrocatalysis, electro-Fenton, electrocoagulation, and electrochemical oxidation have been established as techniques capable of the complete removal of organics including pharmaceuticals from wastewater. Hence, this review presents discussions on the recent progress (literature within 2018-2022) in the applications of common electrochemical processes for the degradation of fluoroquinolone antibiotics from wastewater. The fundamentals of these processes are highlighted while the results obtained using the processes are critically discussed. Furthermore, the inherent advantages and limitations of these processes in the mineralization of fluoroquinolone antibiotics are clearly emphasized. Additionally, appropriate recommendations are made toward improving electrochemical technologies for the complete removal of these pharmaceuticals with minimal energy consumption. Therefore, this review will serve as a bedrock for future researchers concerned with wastewater treatments to make informed decisions in the selection of suitable electrochemical techniques for the removal of pharmaceuticals from wastewater.

Effect of Environmental Concentration of Carbamazepine on the Behaviour and Gene Expression of Laboratory Rats

Carbamazepine (CBZ), an effective drug for epilepsy and other neurological diseases, and its metabolites are one of the most frequently detected substances in the aquatic environment. Although these are doses of very low concentrations, chronic exposure to them can affect the physiological processes of living organisms. This experiment may clarify if carbamazepine, under an environmental and a therapeutic concentration, can affect the behaviour of higher vertebrates, especially mammals, and gene expressions of Ugt1a6 and Ugt1a7 in the brain compared to the control group without exposure to CBZ. Three groups of thirteen rats were randomly formed, and each group was treated either with carbamazepine 12 mg/kg (therapeutic), carbamazepine 0.1 mg/kg (environmental), or by 10% DMSO solution (control). The memory, anxiety, and social behaviour of the rats were assessed by the test Elevated Plus Maze, the novel object recognition test, and the social chamber paradigm. After testing, they were euthanised and brain tissue samples were collected and analysed for mRNA expression of Ugt1a6 and Ugt1a7 genes. The tests did not show significant differences in the behaviour of the rats between the groups. However, there were significant changes at the gene expression level of Ugt1a7.

Bioengineered microbial strains for detoxification of toxic environmental pollutants

Industrialization and other anthropogenic human activities pose significant environmental risks. As a result of the hazardous pollution, numerous living organisms may suffer from undesirable diseases in their separate habitats. Bioremediation, which removes hazardous compounds from the environment using microbes or their biologically active metabolites, is one of the most successful remediation approaches. According to the United Nations Environment Program (UNEP), deteriorating soil health negatively impacts food security and human health over time. Soil health restoration is critical right now. Microbes are widely known for their importance in cleaning up toxins present in the soil, such as heavy metals, pesticides, and hydrocarbons. However, the capacity of local bacteria to digest these pollutants is limited, and the process takes an extended time. Genetically modified organisms (GMOs), whose altered metabolic pathways promote the over-secretion of a variety of proteins favorable to the bioremediation process, can speed up the breakdown process. The need for remediation procedures, degrees of soil contamination, site circumstances, broad adoptions, and numerous possibilities occurring at various cleaning stages are all studied in detail. Massive efforts to restore contaminated soils have also resulted in severe issues. This review focuses on the enzymatic removal of hazardous pollutants from the environment, such as pesticides, heavy metals, dyes, and plastics. There are also in-depth assessments of present discoveries and future plans for efficient enzymatic degradation of hazardous pollutants.

Quantitative structure-activity relationship models for the reaction rate coefficients between dissolved organic matter and PPCPs

To predict PPCPs' photolysis rate in natural aquatic environment, it is essential to grasp the reaction rates between DOM and PPCPs, yet there are few measured data and no prediction models for this important photochemical parameter. To address this, a reaction rate coefficient (α_DOM) was defined to describe the apparent rate of DOM-involved photoreaction for PPCPs. The measured α_DOM values for 40 PPCPs in 9 DOM samples varied dramatically, ranging from (-2.1 ± 0.1)× 10¹⁰ to (2.2 ± 0.1)× 10¹¹ M^-1 s^-1. Then the quantitative structure-activity relationship (QSAR) models were developed using chemical and water quality descriptors via the random forest method. We initially separated positive and negative values by a classifier with an AUC value of 0.965, followed by the construction of regression models for positive and negative values, respectively, using a regressor. Positive models achieved satisfactory goodness-of-fit and predictive ability (R²_adj=0.92 and Q²_ext=0.86), while negative models demonstrated acceptable performance (R²_adj=0.71 and Q²_ext=0.70). Finally, a comprehensive photolysis model that incorporates the QSAR models for α_DOM was established and the significance of water quality parameters was emphasized through sensitive analysis. This model enables more elaborate predictions of PPCPs' photolysis rates in various water samples, providing valuable assistance for forecasting PPCPs' environmental fate.

Materials Based on Co, Cu, and Cr as Activators of PMS for Degrading a Representative Antibiotic-The Strategy for Utilization in Water Treatment and Warnings on Metal Leaching

A chromate of copper and cobalt (Φy) was synthesized and characterized. Φy activated peroxymonosulfate (PMS) to degrade ciprofloxacin (CIP) in water. The Φy/PMS combination showed a high degrading capability toward CIP (~100% elimination in 15 min). However, Φy leached cobalt (1.6 mg L^-1), limiting its use for water treatment. To avoid leaching, Φy was calcinated, forming a mixed metal oxide (MMO). In the combination of MMO/PMS, no metals leached, the CIP adsorption was low (<20%), and the action of SO₄•^- dominated, leading to a synergistic effect on pollutant elimination (>95% after 15 min of treatment). MMO/PMS promoted the opening and oxidation of the piperazyl ring, plus the hydroxylation of the quinolone moiety on CIP, which potentially decreased the biological activity. After three reuse cycles, the MMO still presented with a high activation of PMS toward CIP degradation (90% in 15 min of action). Additionally, the CIP degradation by the MMO/PMS system in simulated hospital wastewater was close to that obtained in distilled water. This work provides relevant information on the stability of Co-, Cu-, and Cr-based materials under interaction with PMS and the strategies to obtain a proper catalyst to degrade CIP.

European-wide spatial analysis of sewage treatment plants and the possible benefits to nature of advanced treatment to reduce pharmaceutical emissions

Pharmaceuticals are known to widely occur in the environment and to affect the health of ecosystems. Sewage treatment plants (STPs) are main emission pathways for pharmaceuticals, which are often not sufficiently removed during wastewater treatment. In Europe, STP treatment requirements are specified under the Urban WasteWater Treatment Directive (UWWTD). The introduction of advanced treatment techniques, such as ozonation and activated carbon, under the UWWTD is expected to be an important option to reduce pharmaceutical emissions. In this study, we present a European-wide analysis of STPs reported under the UWWTD, their current treatment level and potential to remove a set of 58 prioritised pharmaceuticals. Three different scenarios were analysed to show 1) UWWTD present effectiveness, 2) the effectiveness at full UWWTD compliance, and 3) the effectiveness when advanced treatment is implemented at STPs with a treatment capacity of >100.000 person equivalents. Based on a literature study, the potential of individual STPs to reduce pharmaceutical emissions ranged from an average of 9% for STPs with primary treatment to 84% for STPs applying advanced treatment. Results of our calculations show that European-wide emission of pharmaceuticals can be reduced with 68% when large STPs are updated with advanced treatment, but spatial differences exist. We argue that adequate attention should also be paid with regards to preventing environmental impacts of STPs with a capacity <100.000 p.e. Circa 44% of total STP effluent is emitted near Natura2000 sites (EU nature protection areas). Of all surface waters receiving STP effluent for which the ecological status has been assessed under the Water Framework Directive, 77% have a status of less than good. Relatively often only primary treatment is applied to wastewater emitted into coastal waters. This analysis can be used to further model pharmaceutical concentrations in European surface waters, to identify STPs for which more advanced treatment might be required and to protect EU aquatic biodiversity.

Antibiotic pollution of the Yellow River in China and its relationship with dissolved organic matter: Distribution and Source identification

Understanding the sources of antibiotics is important for managing antibiotic contamination and preventing environmental risks in the aquatic environment. In this study, the distribution of dissolved organic matter (DOM) and 24 antibiotics from four typical classes (quinolones, macrolides, sulfonamides and tetracyclines) in the Yellow River basin containing distinct sources of pollution was investigated. In particular, relationships between the antibiotic concentrations and fluorescent properties of DOM were to be established to identify antibiotic sources. A total of 22 antibiotics were detected, with maximum concentrations ranging from 0.27 to 30.14 ng/L in the mainstream of the Yellow River. Of these antibiotics, only erythromycin (ERY) and sulfamethoxazole (SMX) posed potential risks to aquatic organisms. Spatially, tetracyclines were mainly distributed in the upstream reaches of the river, and quinolones were largely distributed in the midstream. High levels of sulfonamides were present downstream of the investigated river. Only EYR belonging to the macrolide group was detected and had a high downstream concentration. EEM-PARAFAC analysis showed that DOM was composed of visible fulvic acid-like fluorescence fraction (C1), ultraviolet fulvic acid-like fluorescence fraction (C2) and protein-like fraction (C3). Using Pearson correlation analysis, this study demonstrated a close relationship between DOM spectral parameters and antibiotic concentrations in the Yellow River basin. Specifically, r (C3, C2) was significantly and positively correlated with the concentrations of SMX, sulfadoxine (SDX), and ERY, while humification index (HIX) had an opposite relationship with these antibiotics. These results suggested that SMX, SDX and ERY were mainly discharged from wastewater treatment plants into the mainstream of the Yellow River. This work provides a powerful demonstration that DOM plays an important role in indicating the occurrence and sources of antibiotics in the aquatic environment.

The determination and prediction of the apparent reaction rates between excited triplet-state DOM and selected PPCPs

To determine and predict the reaction rate between ³DOM* and PPCPs in various water bodies, this study defines a reaction rate coefficient ( [Formula: see text] ) to describe the reaction between ³DOM* and PPCPs. As the values also included the inhibition effect of DOM's antioxidant moieties, the calculation of [Formula: see text] is inconsistent with that of a bimolecular rate constant via the steady-state kinetic method. The [Formula: see text] values of 12 selected PPCPs were determined in two DOM solutions and ten DOM-containing water samples collected from typical surface water bodies in Beijing. The Pearson coefficients between nine predictors including the absorbance ratio (E2/E3), specific absorption coefficient at 254 nm (SUVA₂₅₄), fluorescence index (FI), biological index (BIX), humification index (HIX), pH, total organic carbon (TOC), total fluorescence intensity (TFI) and TOC normalized TFI (TFI/TOC) and [Formula: see text] were examined. Correlation patterns for sulfonamides, β-blockers and diclofenac supported the electron transfer pathway, and was distinctly different from those appeared for FQs where quenching effect played a main part. TFI and TFI/TOC were recognized as the most useful surrogates in empirically predicting [Formula: see text] . For PPCPs that went through the electron transfer pathway, [Formula: see text] could be well fit to the Rehm-Weller model assuming a proportional relationship between TFI and △G_et. For FQs, [Formula: see text] was found to linearly correlated with TFI/TOC. The [Formula: see text] values determined in this study enrich the database of PPCPs photolysis parameters, and the correlation analysis provides reference for forecasting PPCPs fate in the aquatic environment.

Adsorption of the First-Line Covid Treatment Analgesic onto Activated Carbon from Residual Pods of Erythrina Speciosa

In this study, the residual pods of the forest species Erythrina speciosa were carbonized with ZnCl₂ to obtain porous activated carbon and investigated for the adsorptive removal of the drug paracetamol (PCM) from water. The PCM adsorption onto activated carbon is favored at acidic solution pH. The isothermal studies confirmed that increasing the temperature from 298 to 328 K decreased the adsorption capacity from 65 mg g^-1 to 50.4 mg g^-1 (C₀ = 175 mg L^-1). The Freundlich model showed a better fit of the equilibrium isotherms. Thermodynamic studies confirmed the exothermic nature (ΔH⁰ = -39.1066 kJ mol^-1). Kinetic data indicates that the external mass transfer occurs in the first minutes followed by the surface diffusion, considering that the linear driving force model described the experimental data. The application of the material in the treatment of a simulated effluent with natural conditions was promising, presenting a removal of 76.45%. Therefore, it can be concluded that the application of residual pods of the forest species Erythrina speciosa carbonized with ZnCl₂ is highly efficient in the removal of the drug paracetamol and also in mixtures containing other pharmaceutical substances.

Enhanced degradation of emerging contaminants by percarbonate/Fe(II)-ZVI process: case study with nizatidine

Pharmaceuticals have recently emerged as a significant environmental concern due to the growth of population, expansion of industry, and the shift in modern lifestyles. Herein, we present a Fe(II)/percarbonate (SPC) process with dramatically enhanced efficiency by the introduction of zerovalent iron (ZVI). After the addition of ZVI, the removal rate of nizatidine (NZTD) went up from 71.7 to 84.2%. The removal rate of NZTD decreases with rising pH and speeds up with increasing temperature. It was found that under the condition of pH = 7 and T = 25 °C, the molar ratio of the optimal concentration of NZTD degradation in the system was [NZTD]₀:[SPC]₀:[Fe(II)]₀:[ZVI]₀ = 1:8:24:16, with a degradation rate of 99.8%. At the same time, target pollutants can also be successfully eliminated from actual water bodies. Moreover, we test for toxicity using luminescent bacteria, and the results demonstrate that the system is capable of effectively decreasing the toxicity of NZTD. The research findings can contribute to the clarification of the migration and transformation law of NZTD in the oxidation process, thereby providing a scientific basis and technical support for the removal of NZTD in the tertiary water treatment for a water source.

[Disposal of drugs and the ensuing environmental impacts: an integrative review of the literature]

The scope of this article is to investigate the national and international evidence available on the forms of drug disposal and the presence of drugs in environmental matrices. It involved an integrative review of the literature conducted in the PubMed, SciELO and Virtual Health Library (VHL) databases, which included articles in English, Spanish and Portuguese published between 2010 and 2020. Twenty-six articles were selected, which revealed the incorrect disposal of medicines by professionals and consumers due mainly to the lack of knowledge about the environmental impacts that they may cause. Studies have highlighted the contamination of water, sewage and sediments by incorrectly discarded drugs. Furthermore, it was observed that aquatic living creatures can be impacted by the presence of drugs in environmental matrices. The incorrect disposal of drugs continues to be a reality in the evidence assessed, which leads to the contamination of environmental matrices and is often not removed by wastewater treatment plants and interferes with the equilibrium of environmental life.

Presence Of Non-Steroidal Anti-Inflammatories In Brazilian Semiarid Waters

Non-steroidal anti-inflammatory drugs (NSAIDs) act as antipyretics, analgesics and anti-inflammatories. Among them, diclofenac and ibuprofen are the most consumed drugs worldwide. During the COVID-19 pandemic, some NSAIDs, such as dipyrone and paracetamol, have been used to alleviate the symptoms of the disease, causing an increase in the concentrations of these drugs in water. However, due to the low concentration of these compounds in drinking water and groundwater, few studies have been carried out on the subject, especially in Brazil. Thus, this study aimed to evaluate the contamination of the surface water, groundwater, and water treated with diclofenac, dipyrone, ibuprofen, and paracetamol at 3 cities (Orocó, Santa Maria da Boa Vista and Petrolândia) in the Brazilian semiarid region, in addition to analyzing the removal of these drugs by conventional water treatment (coagulation, flocculation, sedimentation, filtration and disinfection) in stations to each city. All drugs analyzed were detected in surface and treated waters. In groundwater, only dipyrone was not found. Dipyrone was seen in surface water with a maximum concentration of 1858.02 μg.L^-1, followed by ibuprofen (785.28 μg.L^-1), diclofenac (759.06 μg.L^-1) and paracetamol (533.64 μg.L^-1). The high concentrations derive from the increased consumption of these substances during the COVID-19 pandemic. During the conventional water treatment, the maximum removal of diclofenac, dipyrone, ibuprofen and paracetamol was 22.42%; 3.00%; 32.74%; and 1.58%, respectively, which confirms the inefficiency of this treatment in removing drugs. The variation in removal rate of the analyzed drugs is due to the difference in the hydrophobicity of the compounds.

Exposure to cadmium induced gut antibiotic resistance genes (ARGs) and microbiota alternations of Babylonia areolata

Cadmium (Cd) is widely distributed in aquatic environments and has multiple adverse effects on aquatic organisms such as the ivory shell (Babylonia areolata). However, its effects on antibiotic resistance genes (ARGs) and gut microbiota of B. areolata remain unclear. In this study, we explored the effects of different concentrations (0, 0.03, 0.18 and 1.08 mg/L) of Cd on intestinal microbial communities and ARGs in B. areolata through 16S rRNA gene sequencing and high-throughput quantitative PCR. The results showed that the structure and diversity of ARGs and microbiota in B. areolata gut were altered upon Cd exposure. Tetracycline, Vancomycin and Macrolide-Lincosamide-Streptogramin B (MLSB) resistance genes were identified as the major ARGs in B. areolata gut. The absolute abundance and alpha diversity of ARGs in B. areolata gut increased with the rise of cadmium concentration. The microbial communities at genus level were enriched in the low and medium Cd concentration groups, while decreased in the high Cd concentration group compared to the control groups. In addition, the influence of microbiota on the ARG profile was more significant than that of Cd concentration and MGEs in B. areolata gut. Null model analysis demonstrated that stochastic processes dominated ARG assembly in the Cd-exposed groups and were enhanced with the increasing Cd concentrations. Four opportunistic bacterial pathogens (Bacteroides, Legionella, Acinetobacter and Escherichia) detected in B. areolata gut maybe the potential hosts of ARGs. Our findings provide references for the hazards assessment of environmental Cd exposure of gut microbiome in aquatic animals.

Carbonized polyaniline-activated peracetic acid advanced oxidation process for organic removal: Efficiency and mechanisms

Recently, advanced oxidation processes (AOPs) based upon peracetic acid (PAA) with high efficiency for degrading aqueous organic contaminants have attracted extensive attention. Herein, a novel metal-free N-doped carbonaceous catalyst, namely, carbonized polyaniline (CPANI), was applied to activate PAA to degrade phenolic and pharmaceutical pollutants. The results showed that the CPANI/PAA system could effectively degrade 10 μM phenol in 60 min with low concentrations of PAA (0.1 mM) and catalyst (25 mg L^-1). This system also performed well within a wide pH range of 5-9 and displayed high tolerance to Cl^-, HCO₃^- and humic acid. The nonradical pathway [singlet oxygen (¹O₂)] was found to be the dominant pathway for degrading organic contaminants in the CPNAI/PAA system. Systematic characterization revealed that the graphitic N, pyridinic N, carbonyl groups (CO) and defects played the role of active sites on CPANI during the activation of PAA. The catalytic capacity of spent CPANI could be conveniently recovered by thermal treatment. The findings will be helpful for the application of metal-free carbonaceous catalyst/PAA processes in decontaminating water.

A Tetranuclear Copper(II)/Calcium(II) Complex as Dual Chemosensor for Colorimetric and Fluorescent Detection of Non-Steroidal Anti-Inflammatory Drugs

The tetranuclear Cu²⁺ /Ca²⁺ /Ca2⁺ /Cu²⁺ complex based on Malten ligand has been investigated as a platform for anion binding. Simple organic carboxylates and non-steroidal anti-inflammatory drugs (NSAIDs) have been tested, revealing the ability of the platform to bind them. The receiving platform hosts at least two guests in solution although a third anion can be bound, as suggested by X-ray diffraction analysis. The addition of the anions is accompanied by a color change of the solution, making the system a colorimetric sensor for carboxylates (LOD values comprised between 3.6 and 20.7 ppm). A fluorescent system consisting of the 2-(3-oxido-6-oxoxanthen-9-yl)benzoate (fluorescein anion) linked to the tetranuclear platform has been also prepared and used in a chemosensing ensemble approach to signal the presence of the selected anions (Log K between 2.6 and 5.6 for the addition of two guests). The latter also works in a paper strip test, offering the chemosensor a possible practical application.

Moving beyond standard toxicological metrics: The effect of diclofenac on planktonic host-parasite interactions

Pharmaceuticals are increasingly released into surface waters and therefore ubiquitous in aquatic systems. While pharmaceuticals are known to influence species interactions, their effect on host-parasite interactions is still underexplored despite potential ecosystem-level consequences. Here, we ask whether diclofenac, a widely used non-steroid anti-inflammatory drug, affects the interaction between a phytoplankton host (Staurastrum sp.; green alga) and its obligate fungal parasite (Staurastromyces oculus; chytrid fungus). We hypothesized that the effect of increasing diclofenac concentration on the host-parasite system depends on parasite exposure. We assessed acute and chronic effects of a wide range of diclofenac concentrations (0-150 mg/L) on host and parasite performance using a replicated long gradient design in batch cultures. Overall system response summarizing parameters related to all biotic components in an experimental unit i.e., number of bacteria and phytoplankton host cells along with photosynthetic yield (a measure of algal cell fitness), depended on diclofenac concentration and presence/absence of parasite. While host standing biomass decreased at diclofenac concentrations >10 mg/L in non-parasite-exposed treatments, it increased at ≥10 mg/L in parasite-exposed treatments since losses due to infection declined. During acute phase (0-48 h), diclofenac concentrations <0.1 mg/L had no effect on host net-production neither in parasite-exposed nor non-parasite-exposed treatments, but parasite infection ceased at 10 mg/L. During chronic phase (0-216 h), host net-production declined only at concentrations >10 mg/L in non-parasite-exposed cultures, while it was overall close to zero in parasite-exposed cultures. Our results suggest that chytrid parasites are more sensitive to diclofenac than their host, allowing a window of opportunity for growth of phytoplankton hosts, despite exposure to a parasite. Our work provides a first understanding about effects of a pharmaceutical on a host-parasite interaction beyond those defined by standard toxicological metrics.

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.

Surface Water Processes Influencing Alterations in Pharmaceutical Chemical Composition following Wastewater Discharge into a Freshwater Estuary

The tidal freshwater Potomac River (TFPR) in the metropolitan Washington, DC region receives wastewater discharge from eight major wastewater treatment plants with the potential to impact water quality. A total of 85 pharmaceutical chemicals and personal care products (PPCPs) were analyzed in surface water and sediments using solid-phase extraction and QuEChERS, respectively, in conjunction with liquid-chromatography tandem mass spectrometry-multiple reaction monitoring quantitation (LC-MS/MS-MRM). A total of 52 PPCPs were quantified in both surface water and sediment. The most frequently quantified PPCPs in water included caffeine, fexofenadine, nicotine, sulfamethoxazole, hydrochlorothiazide, MDA, desvenlafaxine, and metoprolol ranging from 10 to 360 ng/L, and in sediment included diphenhydramine, escitalopram, desvenlafaxine, fexofenadine, sertraline and triclocarban ranging from 20 to 120 ng/g (dry weight). Comparisons of PPCP constituents in WTP discharge and adjacent surface water showed altered compositions reflecting dispersal and transformation processes acted quickly following contact of effluent with surface water. Although the PPCPs were present at their greatest concentrations in surface water near the WTP discharge zones, PPCP concentrations rapidly attenuated yielding mainstem TFPR concentrations relatively consistent along the freshwater reach of the tidal range in the estuary. The PPCP concentrations in sediment maximized in the tributary shoals, but also decreased in the mainstem TFPR similarly to surface water. Compositional analysis showed sorption to geosolids was the most important factor in the loss of PPCPs following WTP discharge in the tributary embayments.

Boosting the Performance of Nanofiltration Membranes in Removing Organic Micropollutants: Trade-Off Effect, Strategy Evaluation, and Prospective Development

In view of the high risks brought about by organic micropollutants (OMPs), nanofiltration (NF) processes have been playing a vital role in advanced water and wastewater treatment, owing to the high membrane performance in rejection of OMPs, permeation of water, and passage of mineral salts. Though numerous studies have been devoted to evaluating and technically enhancing membrane performance in removing various OMPs, the trade-off effect between water permeance and water/OMP selectivity for state-of-the-art membranes remains far from being understood. Knowledge of this effect is significant for comparing and guiding membrane development works toward cost-efficient OMP removal. In this work, we comprehensively assessed the performance of 88 NF membranes, commercialized or newly developed, based on their water permeance and OMP rejection data published in the literature. The effectiveness and underlying mechanisms of various modification methods in tailoring properties and in turn performance of the mainstream polyamide (PA) thin-film composite (TFC) membranes were quantitatively analyzed. The trade-off effect was demonstrated by the abundant data from both experimental measurements and machine learning-based prediction. On this basis, the advancement of novel membranes was benchmarked by the performance upper-bound revealed by commercial membranes and lab-made PA membranes. We also assessed the potentials of current NF membranes in selectively separating OMPs from inorganic salts and identified the future research perspectives to achieve further enhancement in OMP removal and salt/OMP selectivity of NF membranes.