Liver Metabolic Dysregulation Induced by Polypropylene Nano- and Microplastics in Nile Tilapia Using Internal Extractive Electrospray Ionization Mass Spectrometry.

Understanding the metabolic disorders induced by nano- and microplastics in aquatic organisms at the molecular level could help us understand the potential toxicity of nano- and microplastics more thoroughly and provide a fundamental scientific basis for regulating the usage and management of plastic products. In this research, the effect of polypropylene nanoplastics (PP-NPs) and microplastics (PP-MPs) on metabolites in the tilapia liver was comprehensively investigated by internal extractive electrospray ionization mass spectrometry (iEESI-MS). A partial least-squares discriminant analysis (PLS-DA) and a one-component analysis of variance (ANOVA) were used for selecting 46 differential metabolites, including phospholipids, amino acids, peptides, carbohydrates, alkaloids, purines, pyrimidines, and nucleosides. Pathway enrichment analysis showed significant effects on glycerophospholipid metabolism, arginine and proline metabolism, and aminoacyl-tRNA biosynthesis after tilapia were exposed to PP-N/MPs. Dysregulation of these metabolites is mainly reflected in the possible induction of hepatitis, oxidative stress, and other symptoms. The application of iEESI-MS technology without sample pretreatment to the study of metabolic disorders in aquatic organisms under the interference of nano- and microplastics provides a promising analytical method for environmental toxicology research.

Correction: Direct analysis of metabolites in the liver tissue of zebrafish exposed to fiproles by internal extractive electrospray ionization mass spectrometry.

Correction for 'Direct analysis of metabolites in the liver tissue of zebrafish exposed to fiproles by internal extractive electrospray ionization mass spectrometry' by Jun Liu et al., Analyst, 2021, 146, 4480-4486, https://doi.org/10.1039/D1AN00490E.

Internal extractive electrospray ionization mass spectrometry for investigating the phospholipid dysregulation induced by perfluorooctanoic acid in Nile tilapia.

Direct profiling of endogenous biomolecules in tissue samples is considered as a promising approach to investigate metabolic-related toxicity in organisms induced by emerging pollutants. Herein, we report the application of internal extractive electrospray ionization mass spectrometry (iEESI-MS) to direct phospholipid profiling in the liver and spleen tissues of Nile tilapia exposed to perfluorooctanoic acid (PFOA). Combining positive and negative ion detection modes, 130 phospholipid signals were directly detected and identified by iEESI-MS in the tissues of Nile tilapia, including phosphatidyl cholines (PCs), sphingomyelins (SMs), phosphatidic acids (PAs), phosphatidyl ethanolamines (PEs), phosphatidyl glycerols (PGs), phosphatidyl inositols (PIs) and phosphatidyl serines (PSs). With the help of partial least squares discriminant analysis (PLS-DA) and one-way analysis of variance (ANOVA), several phospholipid signals showed a significant difference in the tissue of Nile tilapia between the control group and PFOA exposure groups. In addition, pathway analysis revealed that PFOA has a significant metabolic impact on the glycerophospholipid metabolism in Nile tilapia. Without complex sample preparation, iEESI-MS was applied to direct phospholipid profiling in the liver and spleen tissues of Nile tilapia treated with PFOA, which provided a promising methodology for investigating environmental toxicity and phospholipid-dysregulation caused by emerging pollutants in aquatic organisms.

The effect of carbonization temperature on the capacity and mechanisms of Cd(II)-Pb(II) mix-ions adsorption by wood ear mushroom sticks derived biochar.

Heavy metals often coexist in contaminated environmental media, and competition between heavy metals for adsorption sites influences the absorption capacity of biochar. In this study, the adsorption mechanism of pyrolytically modified wood ear mushroom sticks (250, 450, and 650 °C) as a new bio-adsorbent for single-ion and mixed-ion solutions Cd2+ and Pb2+ Biochar adsorption experiments showed that the adsorption abilities of Cd2+ and Pb2+ increased with increasing WMBC (wood ear mushroom sticks biochar) pyrolysis temperature. According to the Langmuir model, the maximum adsorption capacity of Cd2+ and Pb2+increased with higher pyrolysis temperature, being 29.84, 39.08, 46.16 mg·g-1and 124.3, 186.8, 234.2 mg·g-1, respectively for three different pyrolysis temperatures 250, 450, and 650 °C. WMBC exhibited a stronger adsorption ability for Pb2+ than for Cd2+. Competition between the two heavy metals severely inhibited the adsorption of Cd2+. Based on X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and Fourier transform infrared spectroscopy (FTIR) analyses, the dominant interaction mechanisms were determined to be complexation, ion exchange, precipitation, and C-π interaction. The results suggest WMBC shows promise as a novel, cheap, and effective adsorbent that can be used to remove both Cd2+ and Pb2+ pollutants from environmental media.

Direct analysis of metabolites in the liver tissue of zebrafish exposed to fiproles by internal extractive electrospray ionization mass spectrometry.

Exploring the metabolic disturbance of fipronil and its derivatives in aquatic organisms may provide a more comprehensive understanding of the impact of fipronil on the ecological environment. In this work, internal extractive electrospray ionization mass spectrometry (iEESI-MS) was used to directly analyze metabolites in the liver tissue of zebrafish exposed to fipronil and its three derivatives. Partial least squares-discriminant analysis (PLS-DA) revealed that 32 signals were considered as differential signals in zebrafish after the exposure treatment of fipronil and its derivatives, including phosphatidylcholines (PCs), lysophosphatidylcholines (LPCs), phosphatidylethanolamines (PEs), fatty acids and so on. The pathway analysis result showed that both fipronil and its derivatives have a significant impact on the glycerophospholipid metabolism of zebrafish. Besides, the intensities of PC signals in the liver samples of each group showed such a trend: mixed fiprole exposed group > fipronil sulfone exposed group ≈ fipronil sulfide exposed group > fipronil exposed group > fipronil desulfinyl exposed group > control group, indicating that mixed exposure of fipronil and its derivatives exhibited more significant metabolic disturbance in zebrafish. Taken together, iEESI-MS is applied to environmental toxicology and investigating the metabolic disturbance induced by fipronil and its derivatives in aquatic organisms, providing a new analytical method for this field.

Microalgae biofilm formation and antioxidant responses to stress induce by Lemna minor L., Chlorella vulgaris, and Aphanizomenon flos-aquae.

The study shows how microalgae biofilm formation and antioxidant responses to the production of reactive oxygen species (ROS) is alter by the presences of Lemna minor L., Chlorella vulgaris, and Aphanizomenon flos-aquae. The study involves the cultivation of the biofilm of Chlorella vulgaris and Aphanizomenon flos-aquae in three bioreactors. The condition of growth for the biofilm formation was varied across the three bioreactors to enable the dominance Chlorella vulgaris and Aphanizomenon flos-aquae in one of the bioreactors. Lemna minor L. was also introduce into one of the bioreactors to determine its effect on the biofilm formation. The result obtained shows that C. vulgaris and A. flos-aquae dominate the biofilm, resulting in a high level of H2O2 and O2- (H2O2 was 0.122 ± 0.052 and 0.183 ± 0.108 mmol/L in C. vulgaris and A. flos-aquae, respectively, and O2- was 0.261 ± 0.039 and 0.251 ± 0.148 mmol/L in C. vulgaris and A. flos-aquae, respectively). The study also revealed that the presence of L. minor L. tend to reduce the oxidative stress to the biofilm leading to low production of ROS (H2O2 was 0.086 ± 0.027 and 0.089 ± 0.045 mmol/L in C. vulgaris and A. flos-aquae respectively, and O2- was 0.185 ± 0.044 and 0.161 ± 0.065 mmol/L in C. vulgaris and A. flos-aquae respectively). The variation in the ability of the biofilm of C. vulgaris and A. flos-aquae to respond via chlorophyll, carotenoid, flavonoid, anthocyanin, superoxide dismutase, peroxidase, catalase, glutathione reductase activities, antioxidant reducing power, phosphomolybdate activity, DPPH reduction activity, H2O2 scavenging activity, lipid content and organic carbon also supports the fact that the presence of biomass of microalgae and aquatic macrophytes tend to affect the process of microalgae biofilm formation and the ability of the biofilm to produce antioxidant. This high nutrient utilization leads to the production of biomass which can be used for biofuel production and other biotechnological products.

Potential health risks of metals in skin care products used by Chinese consumers aged 19-29 years.

Metal contamination of skin care products that occurs during their production poses potential health risks, which are of increasing concern, to consumers. Here, we collected 570 responses to an online survey to analyze the usage pattern of skin care products across China. Then a total of 30 commonly used skin care products with various prices and applications were purchased. The concentrations of metals (Al, Zn, Cu, Ni, Cr, Pb, Hg, and Cd) and metalloid As, were determined. Next, we improved the frequency calculation method and used the weighted exposure frequency to calculate the dermal absorption dose (DAD). The amounts of Zn, Cr, and Al that were assimilated by the human body via uptake were approximately 2 orders of magnitude greater than those of Pb, Hg, Cd, Ni and metalloid As. In addition, younger consumers were at higher risk of metals exposure than older consumers because of their higher frequency of use of skin care products. Al and Zn posed higher risk to consumers because of its high DAD. There was no significant chronic non-carcinogenic health risk (hazard index < 1) posed by skincare product use.

Microalgae biofilm cultured in nutrient-rich water as a tool for the phycoremediation of petroleum-contaminated water.

This study aimed at studying the phycoremediation of petroleum-contaminated water using microalgae biofilm cultured in nutrient-rich water. Microalgae biofilm was grown in a photobioreactor containing water rich in calcium nitrate, manganese chloride, sodium potassium tartrate, calcium phosphate, and ammonium sulfate. Petroleum contaminated water was poured into a photobioreactor, and the substrate containing microalgae biofilm was inserted into the photobioreactor and allowed for eight weeks for biofilm formation. Physicochemical parameters (pH, turbidity, conductivity, sulfate, alkalinity, chloride, TDS, TSS, nitrate, salinity, iron, potassium, phosphate, chlorine, chromium, magnesium, zinc, COD, BOD, and total petroleum hydrocarbon (TPH) of the petroleum contaminated water before and after treatment were determined. The microalgae biofilm used for the treatment was characterized before and after treatment using a Scanning Electron Microscope, X-Ray Fluorescence, and Fourier-transform infrared spectroscopy. The phytochemical constituent of the microalgae biofilm was also determined before and after treatment of the petroleum-contaminated water. The result obtained shows highest removal efficiency of physicochemical parameters (turbidity (81%), conductivity (51.2), sulfate (17.5%), alkalinity 28.4%), chloride (14.6%), TDS (7.9), TSS (26%), nitrate (33%), salinity (23.4), iron (16%), potassium (22%), phosphate (28.2%), chlorine (14%), chromium (13.6%), magnesium (30.3%), zinc (40.5%), COD (8%), BOD (16.7%) and total petroleum hydrocarbon (15%)). The microalgae's characterization shows microalgae biofilm's ability to adsorb pollutants in petroleum-contaminated water due to the presence of microspores and larger surface area of the cells of the microalgae forming the biofilm or due to the absorption efficiency of the extracellular polymeric substances (EPS). The analysis of the microalgae biofilm's phytochemical parameters shows the involvement of the chemicals components in pollutants degradation and antioxidant response of the microalgae to counteract the oxidative effect resulting from the exposure of the microalgae to the contaminated water. NOVELTY STATEMENT This is the first study that attempts the phycoremediation of petroleum contaminated water using microalgae biofilm. The reduction efficiency of the parameters treated in this study is very low compared to that reported in the literature but increases with the retention day. This low reduction efficiency is attributed to the slow assimilation of organic and inorganic pollutants due to the initial growth condition. This study is the first to re-affirm that microalgae biofilm can phycoremediate petroleum-contaminated water by adsorption and assimilation due to the presence of microspores and a larger surface area the cells of the microalgae forming the biofilm or the extracellular polymetric surface covering the biofilm. Several studies have reported that phytochemicals present in microalgae play an antioxidant response role to prevent the microalgae from oxidative damage resulting from water pollution. However, this study is the first to strongly link phytochemicals to the enhancement of pollutants degradation and adsorption by microalgae biofilm.

The efficiency of microalgae biofilm in the phycoremediation of water from River Kaduna.

This study is aimed at investigating the efficiency of microalgae biofilm in the phycoremediation of water from a polluted river. Freshwater microalgae biofilm inherent in a contaminated petrochemical stream was employed to remediate water from the River Kaduna, which is the largest river in Kaduna town, Kaduna State, Nigeria, and serves as the primary water source in Kaduna town. The results indicate high reduction efficiency of some physicochemical parameters and pollutants (turbidity (71%), conductivity (9.8%), sulfate (37.5%), alkalinity (62.5%), chloride (11.5%), TDS (9.9%), TSS (66.7%), nitrate (42.9%), COD (24%), and BOD (33%), Cd (70.0%), Ni (74.0%) and Pb (71.0%)), indicating the effectiveness of microalgae biofilm in the phycoremediation of water from River Kaduna. According to scanning electron microscope (SEM) observation, the microalgae biofilm has rough surface morphology after the treatment of the river water, which implies that the biofilm was capable of removing the pollutants in water via biosorption. Other characterizations such as XRF, XRD, and FTIR also buttressed that biosorption was the primary removal mechanism of pollutants by microalgae biofilm. Besides, the results also show the production of ROS during the treatment of water from the River Kaduna by the microalgae biofilm. This high concentration of ROS produced during the treatment correlates significantly with pollutant degradation. The GC-MS analysis of the microalgae biofilm shows the involvement of some phytochemicals in the process of pollutant degradation. As a result, microalgae biofilm is a simple and cost-effective method of polluted water phycoremediation with promising applications and future prospects.

The Toxicological Effects of Mercury Exposure in Marine Fish.

Since the Minamata incident in Japan, the public have become increasingly aware of the negative health effects caused by mercury pollution in the ocean. Consequently, there has been significant interest in the health of humans eating fish exposed to mercury (Hg). However, the toxicity of mercury to the marine fish themselves has received far less attention. In this review, we summarize mercury accumulation in marine fish and the toxicological effects of mercury exposure. Results showed that the bioaccumulation of mercury in marine fish was highly variable, and its concentration was affected by the specific physiological and ecological characteristics of different fish species. Mercury exposure can produce teratogenic, neurotoxic effects, and reproductive toxicity. These effects can then cause harm to cells, tissues, proteins and genes, and ultimately, the survival, growth, and behavior of marine fish. Future studies should afford more attention to the toxicological effect of mercury exposure upon marine fish.

Polycyclic aromatic hydrocarbons (PAHs) in an urban river at mid and high latitudes: A case study in Siping, a traditional industrial city in Northeast China.

The occurrence, spatial distribution, seasonal variation, sources, and ecological risks of polycyclic aromatic hydrocarbons (PAHs) in overlying water and surface sediments from Tiaozi River, which is an urban river running through the downtown of Siping City, a traditional industrial city of northeastern China, were investigated. The total PAH concentrations (ΣPAHs) in water varied from 473.5 to 2674.3 ng/L with a mean value of 1272.6 ng/L and ranged from 601.5 to 2906.3 ng/g with a mean value of 1534.4 ng/g in sediments. Both the individual and total PAH concentrations in water and sediments decreased from upstream to downstream, and the average ΣPAHs between the four seasons in water and sediments decreased in the following order of winter> autumn> spring> summer. The composition of the PAHs was characterized by an abundance of PAHs from 2 rings to 4 rings, and the predominant components were naphthalene, chrysene, and benzo(a)anthracene. The identification of the source indicated that coal combustion could be the main contributor to the PAHs. The equivalent toxic concentrations of benzo[a]pyrene in the water ranged from 11.5 to 33.1 ng/L, which were much higher than the concentration limit, suggesting that PAHs in the water could cause potential risks. The risk assessment of PAHs in sediments also showed that PAHs could cause negative effects on aquatic organisms in this river.

Ammonia nitrogen removal and recovery from acetylene purification wastewater by air stripping.

Ammonia nitrogen (NH4-N) contaminated wastewater has posed a great threat to the safety of water resources. In this study, air stripping was employed to remove and recover NH4-N from acetylene purification wastewater (APW) in a polyvinylchloride manufacturing plant. Investigated parameters were initial APW pH, air flow rate, APW temperature and stripping time. The NH4-N removal by air stripping has been modeled and the overall volumetric mass transfer coefficient (KLa) of the stripping process has been calculated from the model equation obtained. In addition, the ability of H2SO4 solution to absorb the NH3 stripped was also investigated. The results indicated that under the experimental conditions, the APW temperature and its initial pH had significant effects on the NH4-N removal efficiency and the KLa, while the effects of other factors were relatively minor. The removal efficiency and residual concentration of NH4-N were about 91% and 12 mg/L, respectively, at the optimal operating conditions of initial APW pH of 12.0, air flow rate of 0.500 m3/(h·L), APW temperature of 60 °C and stripping time of 120 min. One volume of H2SO4 solution (0.2 mol/L) could absorb about 93% of the NH3 stripped from 54 volumes of the APW.

Ammonia nitrogen removal from acetylene purification wastewater from a PVC plant by struvite precipitation.

Acetylene purification wastewater (APW) usually contains high concentrations of ammonia nitrogen (NH4-N), which is generated during the production of acetylene in a polyvinylchloride manufacturing plant. In this study, a struvite precipitation method was selected to remove NH4-N from the APW. Laboratory-scale batch experiments were performed to investigate the effects of the initial APW pH, phosphate (PO4(3-)) concentration, magnesium (Mg(2+)) concentration, and sources of PO4(3-) and Mg(2+) on NH4-N removal. The results indicated that the initial APW pH had a significant effect on the removal of NH4-N, while the other factors had relatively minor effect. The NH4-N could be effectively removed at an optimum initial APW pH of 9.5, when Na2HPO4·12H2O and MgSO4·7H2O were both applied to NH4-N at a ratio of 1.2. Under these conditions, the efficiency of removal of NH4-N, total nitrogen and chemical oxygen demand were 85%, 84% and 18%, respectively. The X-ray diffraction analysis indicated that the precipitates were dominated by struvite. The scanning electron microscopy analysis of the precipitates showed a typical morphology of stick-like and prismatic crystals with coarse surface. The energy dispersive spectroscopy analysis indicated that the precipitates contained P, O, Mg and Ca.

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

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

Inactivation of antibiotic resistant bacteria by Fe3O4 @MoS2 activated persulfate and control of antibiotic resistance dissemination risk.

Antibiotic resistance poses a global environmental challenge that jeopardizes human health and ecosystem stability. Antibiotic resistant bacteria (ARB) significantly promote the spreading and diffusion of antibiotic resistance. This study investigated the efficiency and mechanism of inactivating tetracycline-resistant Escherichia coli (TR E. coli) using Fe3O4 @MoS2 activated persulfate (Fe3O4 @MoS2/PS). Under optimized conditions (200 mg/L Fe3O4 @MoS2, 4 mM PS, 35 °C), TR E. coli (∼7.5 log CFU/mL) could be fully inactivated within 20 min. The primary reactive oxygen species (ROS) responsible for TR E. coli inactivation in the Fe3O4 @MoS2/PS system were hydroxyl radicals (•OH) and superoxide radicals (•O2-). Remarkably, the efflux pump protein was targeted and damaged by the generated ROS during the inactivation process, resulting in cell membrane rupture and efflux of cell content. Additionally, the horizontal transmission ability of residual antibiotic resistance genes (ARGs) harboring in the TR E. coli was also reduced after the inactivation treatment. This study offers an efficient approach for TR E. coli inactivation and substantial mitigation of antibiotic resistance dissemination risk.

Diversity characterization of bacteria and fungi in water, sediments and biofilms from Songhua River in Northeast China.

Water, sediments, and biofilms are the typical microbial carriers in natural water environments. However, comparative analysis of the distribution of bacterial and fungal communities in different carriers within the same habitat is relatively lacking. Therefore, this study employed 16 S and ITS rRNA gene sequencing to identify bacterial and fungal community structures in water, sediments, and biofilm. The results show that (1) the OTUs numbers revealed that the bacterial abundance, at the levels of species, genus, and family, followed the order of sediments > water > biofilms, while the fungal abundance order was water > sediments > biofilms. In addition, bacteria were mainly present in sediments, while fungi were mainly present in water. (2) The α diversity index (Shannon, ACE, Simpson, and Chao1) order, for bacteria was: sediments > water > biofilms, indicating that the diversity and homogeneity of bacteria in sediments were relatively higher; for fungi was: water > sediments > biofilms, indicating that the diversity and abundance of fungi in water were high. (3) The core phylum of bacterial in the water, sediments, and biofilms was Cyanobacteria (31.3-46.1%) and Actinobacteria (27.6-36.1%); Proteobacteria (35.0-41.8%), Cyanobacteria (14.7-36.6%); and Proteobacteria (63.3-69.2%), respectively. (4) The mainly colonized fungal phyla in biofilms in the water, sediments, and biofilms were Basidiomycota (29.3-38.7%) and Ascomycota (16.2-27.7%); Zygomycota (13.1-17.5%), Basidiomycota (5.6-17.6%); and Zygomycota (23.8-44.2%). (5) There were significant species differences in bacterial and fungal communities in water, sediments, and biofilm by NMDS analysis. Findings are useful for guiding significance for the Biogeochemical cycle of elements, the environmental fate of pollutants, and the study of water ecosystems.

Photocatalytic Degradation of Acetaminophen in Aqueous Environments: A Mini Review.

Over the past few decades, acetaminophen (ACT), a typical nonsteroidal anti-inflammatory drug (NSAID), has gained global usage, positioning itself as one of the most extensively consumed medications. However, the incomplete metabolism of ACT leads to a substantial discharge into the environment, classifying it as an environmental contaminant with detrimental effects on non-target organisms. Various wastewater treatment technologies have been developed for ACT removal to mitigate its potential environmental risk. Particularly, photocatalytic technology has garnered significant attention as it exhibits high efficiency in oxidizing and degrading a wide range of organic pollutants. This comprehensive review aims to systematically examine and discuss the application of photocatalytic technology for the removal of ACT from aqueous environments. Additionally, the study provides a detailed overview of the limitations associated with the photocatalytic degradation of ACT in practical applications, along with effective strategies to address these challenges.

Visible-light-driven photocatalytic degradation of tetracycline hydrochloride by Z-scheme Ag3PO4/1T@2H-MoS2 heterojunction: Degradation mechanism, toxicity assessment, and potential applications.

Residual antibiotics in wastewater threaten living organisms and the ecosystem, while the photocatalytic process is recognized as one of the most eco-friendly and promising technologies for the treatment of antibiotic wastewater. In this study, a novel Z-scheme Ag3PO4/1T@2H-MoS2 heterojunction was synthesized, characterized, and used for the visible-light-driven photocatalytic degradation of tetracycline hydrochloride (TCH). It was found that Ag3PO4/1T@2H-MoS2 dosage and coexisting anions had significant effects on the degradation efficiency, which could reach up to 98.9 % within 10 min under the optimal condition. Combing experiments and theoretical calculations, the degradation pathway and mechanism were thoroughly investigated. The excellent photocatalytic property of Ag3PO4/1T@2H-MoS2 was achieved attributed to the Z-scheme heterojunction structure, which remarkably inhibited the recombination of photoinduced electrons and holes. The potential toxicity and mutagenicity for TCH and generated intermediates were evaluated, which revealed the ecological toxicity of antibiotic wastewater was reduced effectively during the photocatalytic degradation process.

{N'-[(2-Oxidonaphthalen-1-yl)methyl-idene]benzohydrazidato}(1,10-phenanthroline)copper(II) methanol monosolvate.

The title mononuclear complex, [Cu(C(18)H(12)N(2)O(2))(C(12)H(8)N(2))]·CH(3)OH, contains one N'-[(2-oxidonaphthalen-1-yl)methyl-idene]benzohydrazidate ligand (L(2-)), a Cu(2+) cation, one 1,10-phenanthroline ligand and a methanol solvent mol-ecule. The Cu(II) ion adopts a CuO(2)N(3) distorted square-pyramidal coordination. An O-H⋯O hydrogen bond is formed between the methanol solvent mol-ecule and the hydrazide O atom of the L(2-) ligand.

Photodegradation of norfloxacin in ice: Role of the fluorine substituent.

Ice is an important medium in cold regions, because it regulates the environmental behaviors and the fate of pollutants. The photodegradation of fluoroquinolone (FQ) antibiotics as emerging contaminants of concern in ice remains poorly understood. Here, the photodegradation of fluorine-containing norfloxacin (NOR) as one model of FQs in ice formed from freezing solutions was investigated. Pipemidic acid (PPA) as a structural analogue of NOR was selected to compare the effect of molecular structure on the antibiotic photodegradation in the ice. Results suggested that the photodegradation rate constant of NOR in ice relative to pure water increased by 40.0%. Both the absorbance in the absorption spectra and quantum yields of NOR in ice over water increased by 1.4 times. Direct photodegradation mainly caused the defluorination of NOR, which was more important than cleavage and oxidation of the piperazine ring by self-sensitized photooxidation in ice. The defluorination rate of NOR in the ice relative to water increased by about 12.7%. The fluorine substituent played a more important role in the NOR photodegradation in the ice, resulting in a 1.6-fold increase in the photodegradation rate constant of NOR relative to PPA. This work provides a new insight into the role of fluorine substituents in the photodegradation of fluorinated pharmaceuticals in cold regions.