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Abstract We used a hybrid precipitation method to simultaneously extract and analyze 24 personal care products (PCPs), including 16 biocides, 4 synthetic musks, and 4 benzotriazoles, in the plasma of fish. The method's performance was validated for plasma samples with and without β -glucuronidase/aryl-sulfatase hydrolysis. The recoveries were in the range of 70–120% for most of the PCPs, except N , N -diethyl-3-methylbenzamide (DEET), clotrimazole (CTZ), miconazole and itraconazole at spiking concentration of 20 and 5 ng/mL. The quantification limits ranged between 0.89 and 17.9 ng/mL (hydrolyzed plasma) and 0.85–18.5 ng/mL (non-hydrolyzed plasma), except CTZ at 77.5 ng/mL and 76.3 ng/mL. Totally, 13 PCPs were detected in plasma samples of fish collected from the Yangtze River, with a maximum concentration of 58.4 ng/mL (galaxolide). Compounds with the phenol hydroxyl groups of parabens or triclosan in hydrolyzed plasma showed higher concentrations than those in unhydrolyzed plasma with the ratio of conjugation (glucuronides + sulfates) forms up to 86%. The median values for the logarithm of bioaccumulation factors were between 1.39 and 4.15, which were 2–3 orders of magnitude higher than the theoretical logarithm of bioconcentration factors. Using the fish plasma model, the effect ratios (effect concentration/measured plasma concentration ratios) of tonalide, galaxolide, benzotriazole, triclosan, and DEET reached 0.35, 4.15, 3.78, 7.52, and 9.24, respectively. These are recognized as priority chemicals for further risk assessment. Graphical abstract Unlabelled Image Highlights • A method was developed to determine personal care products (PCPs) in fish plasma. • The MQLs of most PCPs ranged at 0.85–18.5 ng/mL (except clotrimazole at 77.5 ng/mL). • Thirteen PCPs were detected in plasma from fish collected from the Yangtze River. • Parabens and triclosan with OH group showed high ratio of conjugation up to 86%. • Five PCPs are recognized as the priority attended chemicals. [ABSTRACT FROM AUTHOR]

Abstract Animal manure contains various organic contaminants such as steroids. The fate of these steroids during composting is still unknown. Here we investigated the fate of androgens, progestogens, and glucocorticoids during animal manure composting and evaluated their residues in compost-applied soils. The results showed the presence of 16 steroid hormones in the initial compost with concentrations ranging from 3.26 ng/g dw (Cortisol) to 2520 ng/g dw (5α-dihydroprogesterone). The concentrations of almost all detected hormones increased on the 2nd day of composting, and some of them increased several or even dozens of times. Steroids such as hydroxyprogesterone caproate, melengestrol acetate, and methyltestosterone were not found in the initial compost but later detected during the composting process. After 171 days of composting, only 40.4% of detected steroid hormones was removed, and the total concentration of detected steroids was still as high as 3210 ng/g dw. The removal rates of some target compounds were negative, especially for the natural androgens androsta-1,4-diene-3,17-dione and the synthetic androgen 17β-boldenone whose concentrations significantly increased by the end of composting, indicating conversion from their conjugates or transformation from other steroids. The steroid hormones were mainly eliminated in the first three weeks; prolonged composting time did not obviously promote further removal. The variations in steroid concentration were related to the changes in compost properties such as pH and temperature during the composting process. The dissipation of steroid hormones was also linked to the changes of microbial communities in the compost to some extent. Twelve steroids were detected in the compost-treated soils of a kailyard, while 26 steroid hormones were detected in the roots of Chinese cabbages grown on the soil. The results suggest that the application of manure compost product can lead to soil contamination and plant uptake. Graphical abstract Unlabelled Image Highlights • We investigated fate of steroid hormones during manure composting process. • 19 of 40 target steroid hormones were detected in compost. • Steroid hormones persisted in composting with a total removal rate of 40.4%. • Dissipation was related to the compost properties and microbial communities. • Steroid hormones were detected in the compost-treated soils and cabbages. [ABSTRACT FROM AUTHOR]

Abstract Dydrogesterone (DDG) is a synthetic progestin broadly used in human and veterinary medicine and has been widely detected in aquatic environments. However, its potential effects on aquatic organisms are little documented. Here we investigate the short-term effects of DDG on the transcriptional and histological responses in adult zebrafish (Danio rerio). Adult zebrafish were exposed to 32.0, 305 and 2490 ng L−1 of DDG for 14 days. Real time quantitative PCR analysis showed that DDG significantly increased transcripts of most genes involved in the gonadotropin–releasing hormone (GnRH) pathway in the brain of female. In contrast, apparent down-regulation of these gene transcriptions was observed in the brain of males. The transcription of cyp19a1a in the ovary had a 2.3 fold increase at 2490 ng L−1 of DDG and the transcription of hsd17b2 at 305 and 2490 ng L−1 in the testis was enhanced by approximately 2.0 fold and 2.4 fold, respectively. Histopathological analysis revealed exposure to 2490 ng L−1 DDG significantly increased the percentage of atretic follicles in the ovary. The results of this study suggest that DDG has potential endocrine disrupting effects and affects the ovarian development in zebrafish. Graphical abstract Image 1 Highlights • DDG influenced gonadotropin genes. • DDG affected transcription of steroidogenesis genes in gonads. • Transcriptional alteration displayed sex−dependent. • DDG increased frequency of atretic follicles. [ABSTRACT FROM AUTHOR]

[Display omitted] • We identified 75 Antimicrobial drugs (ADs) and 314 transformed products (TPs). • Tetracyclines has the highest concentration and strongest migration ability in soil. • Ten ADs were reported for the first time from suspect screening. • The main transformed pathway was microbial/enzymatic metabolism. • Attentions should be paid for the significant number of less-concerned ADs and TPs. Swine farms contaminated the surrounding environment through manure application and biogas slurry irrigation, hence causing the wide residual of multiple antimicrobial drugs (ADs) and their transformation products (TPs). This study performed target, suspect, and nontarget screening methods to comprehensively investigate the pollution profiles of ADs in a typical swine farm, and characterize the potential transformed pathway of TPs and distinguish specific reactions of different catalog of ADs. Samples of fresh feces, compost, biogas slurry, topsoil, column soil, groundwater and plants were analyzed using the database containing 98 target analytes, 679 suspected parent ADs, and ∼ 107 TPs. In total, 29 ADs were quantitively detected, and tetracyclines (TCs) were mostly frequently detected ADs with the concentrations up to 4251 ng/g in topsoil. Soil column investigation revealed that doxycycline (DOX) and tetracycline (TC) in soil could migrate to depths of approximately 1 m in soil. Suspect screening identified 75 parent ADs, with 10 being reported for the first time in environmental media. Semi-quantification of ADs revealed that one of the less-concerned ADs, clinafloxacin, was detected to exceed 5000 ng/L in biogas slurry, suggesting that significant attentions should be paid to these less-concerned ADs. Moreover, 314 TPs was identified, and most of them were found to undergo microbial/enzymatic metabolism pathways. Overall, our study displays a comprehensive overview of ADs and their TPs in swine farming environments, and provides an inventory of crucial list that worthy of concern. The results emphasize the need to quantify the levels and distribution of previously overlooked ADs and their TPs in livestock farms. [ABSTRACT FROM AUTHOR]

Antibiotics are increasingly used and released into the marine environment due to the rapid development of mariculture, resulting in spread of antibiotic resistance. The pollution, distribution, and characteristics of antibiotics, antibiotic resistance genes (ARGs) and microbiomes have been investigated in this study. Results showed that 20 antibiotics were detected in Chinese coastal environment, with predominance of erythromycin-H 2 O, enrofloxacin and oxytetracycline. In coastal mariculture sites, antibiotic concentrations were significantly higher than in control sites, and more types of antibiotics were detected in the South than in the North of China. Residues of enrofloxacin, ciprofloxacin and sulfadiazine posed high resistance selection risks. β -Lactam, multi-drug and tetracycline resistance genes were frequently detected with significantly higher abundance in the mariculture sites. Of the 262 detected ARGs, 10, 26, and 19 were ranked as high-risk, current-risk, future-risk, respectively. The main bacterial phyla were Proteobacteria and Bacteroidetes, of which 25 genera were zoonotic pathogens, with Arcobacter and Vibrio in particular ranking in the top10. Opportunistic pathogens were more widely distributed in the northern mariculture sites. Phyla of Proteobacteria and Bacteroidetes were the potential hosts of high-risk ARGs, while the conditional pathogens were associated with future-risk ARGs, indicating a potential threat to human health. [Display omitted] • 20 antibiotics and 262 ARGs were detected in mariculture of coastal China. • Antibiotic residues could pose resistance selection risks. • β-Lactam, multi-drug and tetracycline resistance genes were frequently detected. • Proteobacteria and Bacteroidetes were the potential hosts of high-risk ARGs. • The results suggest potential health risks associated with the coastal mariculture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Swine farming shifted airborne bacterial communities and antibiotic resistomes. • Swine feces contributed 77% of bacteria and 48% of AMR in the air. • Firmicutes bacteria including Streptococcus and Clostridium were major ARG hosts. • Streptococcus alactolyticus carried multiple (MGE-associated) ARGs and VFGs. • Swine farm air faced higher AMR and inhalation exposure risks than hospital air. Globally extensive use of antibiotics has accelerated antimicrobial resistance (AMR) in the environment. As one of the biggest antibiotic consumers, livestock farms are hotspots in AMR prevalence, especially those in the atmosphere can transmit over long distances and pose inhalation risks to the public. Here, we collected total suspended particulates in swine farms and ambient air of an intensive swine farming area. Bacterial communities and antibiotic resistomes were analyzed using amplicon and metagenomic sequencing approaches. AMR risks and inhalation exposure to potential human-pathogenic antibiotic-resistant bacteria (HPARB) were subsequently estimated with comparison to the reported hospital samples. The results show that swine farms shaped the airborne bacterial community by increasing abundances, reducing diversities and shifting compositions. Swine feces contributed 77% of bacteria to swine farm air, and about 35% to ambient air. Airborne antibiotic resistomes in swine farms mainly conferred resistance to tetracyclines, aminoglycosides and lincosamides, and over 48% were originated from swine feces. Distinct to the hospital air, Firmicutes were dominant bacteria in swine farming environments with conditional pathogens including Clostridium , Streptococcus and Aerococcus being major hosts of antibiotic resistance genes (ARGs). Therein, genomes of S. alactolyticus carrying (transposase/recombinase-associated) ARGs and virulence factor genes were retrieved from the metagenomes of all swine feces and swine farm air samples, but they were not detected in any hospital air samples. This suggests the indication of S. alactolyticus in swine farming environments with potential hazards to human health. Swine farm air faced higher AMR risks than hospital air and swine feces. The inhalation intake of HPARB by a swine farm worker was about three orders of magnitude higher than a person who works in the hospital. Consequently, this study depicted atmospheric transmission of bacteria and antibiotic resistomes from swine feces to the environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tire additives and transformation products are ubiquitous in urban water system. • 1,3-Diphenylguanidine and some transformation products are the dominant compounds in most samples. • 6PPD-Quinone is firstly reported in surface water and drinking water treatment plant in China. • Surface runoff and wastewater treatment plants as sources of tire additives in urban water systems. • 6PPD-Quinone and N , N' -Di-2-naphthyl-p-phenylenediamine displayed high ecological risks in some sites of surface water. Tire wear particles (TWPs) enter road surface with the friction between tires and road surfaces. Under the volatilization, leaching, and transformation action on TWPs by sunlight and rain, tire additives are released into urban water systems, such as surface rainfall runoff, wastewater treatment plants (WWTPs), receiving surface waters, and drinking water treatment plant (DWTP). In this study, we investigated the occurrence of 23 tire additives and their transformation products in the urban water system of the Pearl River Delta region, South China. Nineteen target compounds were detected in the surface runoff, with 1,3-Diphenylguanidine (DPG) showing highest maximum concentration of 58780 ng/L. Benzothiazole and its transformation products are detected at the frequency of 100 % with the total concentrations of 480–42160 ng/L. The antioxidant derivative N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine-quinone (6PPD-Q) was also detected up to 1562 ng/L, which was considerably higher than that of the parent compound 6PPD (the maximum concentration of 7.52 ng/L). Eleven and 8 compounds were detected in WWTPs influents and effluents, respectively, with removal rates of − 62–100 %. Seventeen compounds were detected in the receiving Zhujiang and Dongjiang rivers, while 9 compounds were detected in drinking water sources and DWTP samples. Road runoff, with total concentrations of target compounds up to 79200 ng/L, is suggested as the main non-point source for receiving rivers, while WWTPs effluents are the point sources due to incomplete removal of target compounds after accepting the initial runoff. 6PPD-Q and other 10 compounds displayed median to high ecological risks in surface waters, and the human daily intake of tire additives was estimated to be 2.63 × 10−8-3.16 × 10−5 mg/(kg d) via drinking water. This is the first report of the 6PPD-Q and 1,3-Diphenylurea levels in surface waters in China. [ABSTRACT FROM AUTHOR]

• Multi-residue analysis for 151 chemicals in fish was developed and validated. • Captiva EMR-Lipid cartridge showed better protein removal efficiency than QuEChERS. • LC-QTOF-MS/MS combined with Captiva EMR-Lipid cartridge showed good performance. • 867 chemicals were tentatively identified in cultured fish by nontarget screening. An effective analytical method for target and non-target screening of multi-class emerging organic chemicals in aquaculture fish muscle samples using liquid chromatography coupled with high resolution time-of-flight mass spectrometry (LC-QTOF-MS/MS) was reported. Two sample pretreatment methods (QuEChERS and Captiva EMR-Lipid cartridge) were compared and assessed for 151 organic compounds covering a wide range of log Kow (-1.37—11.51) in freeze-dried fish samples. Captiva EMR-Lipid cartridge outperformed QuEChERS by high detection frequency (> 87.5%) and effective matrix removal with satisfactory standard deviation of the compounds (< 20%), and meanwhile provided acceptable recoveries for most organic chemicals at three spiking concentration levels (10, 50, and 100 ng g−1). Spiking experiments suggested that the developed non-target screening workflow showed further convincible identification results with over 83.3% of the chemicals confirmed at even low spiking levels. A list of 867 organic chemicals were tentatively identified in fish samples collected from fish ponds with 21 of them classified as high confidence levels (L1 and L2). The results showed that the simplified analytical strategy can be applied for the quantification and screening analysis of a broad range of emerging organic chemicals in fish samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Non-target and target screening of PFAS was conducted in a drinking water system. • Nine out of 50 target PFAS were detected with concentrations of

Wide use of various chemicals has resulted in water pollution, which has become a global environmental concern. So far limited information is available on what chemicals in our water. Here we investigated the occurrence and profiles of organic chemicals in the North River, South China by applying non-target screening analysis with high resolution mass spectrometry. A total of 402 organic chemicals belonging to eleven categories were identified in the North River, with notable presence of industrial chemicals, pharmaceuticals and pesticides. Among these detected chemicals, over half of the tentatively identified compounds were rarely reported in the surface water, with a few compounds, e.g., sisomicin, simeton, 2-methyl-4,6-dinitrophenol, xanthurenic acid and indole-3-carboxylic acid that have never been documented in the North River before, while the metabolites like 4-acetamidoantipyrine were also observed. The maximum concentration of the identified chemicals in the North River was above 300 ng/L (Sulfamonomethoxine). Principle component analysis results of the obtained dataset showed significant seasonal distribution, which could be linked to variations in wastewater discharge, river dilution and anthropogenic activities such as pesticide spray. Agricultural activities in the upper reaches led to detection of various pesticides in the river basin, especially in the wet season. The findings from this study demonstrated the widespread presence of chemicals in our waterway, and further retrospective analysis would reveal more information about chemicals of emerging concern. [Display omitted] • Non-target analysis was performed to identify organic chemicals in the North River. • A total of 402 organic chemicals was identified in the water. • Industrial chemicals, pharmaceuticals and pesticides were predominant in the river. • >50% of the identified compounds have not been reported in the river before. • This study demonstrates the widespread presence of chemicals in our waterway. [ABSTRACT FROM AUTHOR]

Poly- and perfluoroalkyl substances (PFASs) are contaminants of global concern. Studies in Pearl River, south China have focused on the delta area, while the upstream contributions are unclear. Here, we systematically investigated the fate, trends and potential sources of 57 PFASs in river water, sediment and fish of the North and West Rivers of the Pearl River system. Perfluorooctanoic acid (PFOA), Perfluorooctanesulfonic acid (PFOS) and 6:2 chlorinated polyfluoroalkyl ether sulfonate (6:2Cl-PFESA) were frequently found compounds in waters, sediments and fish, suggesting their wide usage in this area and potential for bioaccumulation. Waters showed a higher ∑PFASs in the wet season compared to the dry season, but sediments did not. The North River contributed higher PFAS loads to the Pearl River Delta. Our results also reflect the current shift in PFAS usage from legacy substances to alternatives. This study, for the first time, reports data on PFASs in two upstream rivers of the Pearl River and on alternative PFASs such as PFESA in this area, which can better the understanding of their use, fate, risk assessment and further controls and management. [Display omitted] • Legacy and alternative PFASs were investigated in two river systems, South China. • PFOA, PFOS and 6:2 Cl-PFESA were the most frequently detected compounds. • PFAS profiles in surface water differed between rivers and sampling seasons. • Legacy PFASs are being replaced by alternative PFASs at Pearl River Basin. [ABSTRACT FROM AUTHOR]

Trace antiviral drug contamination in aquatic ecosystems is becoming a significant environmental concern that requires an urgent efficient determination method. Here we developed sensitive and robust multi-residue determination methods to simultaneously extract and analyze 9 commonly used antiviral drugs (abacavir, zidovudine, efavirenz, nevirapine, ritonavir, lopinavir, lamivudine, telbivudine and entecavir) in surface water, wastewater, sediment, and sludge. Water samples were extracted with solid-phase extraction (SPE) technique using tandem hydrophilic–lipophilic balance and graphitized carbon black cartridges, while sediment and sludge samples were extracted using QuEChERS (quick, easy, cheap, effective, rugged, and safe) method. The extraction conditions of SPE (pH and cartridge type) and QuEChERS (acetic acid content, salts reagent, and purification sorbent) methods were carefully optimized. We observed that under optimum conditions, the method quantification limits of the 9 antiviral drugs in water and solid samples ranged from 0.05 to 19.23 ng L−1 and from 0.02 to 7.38 ng g−1, respectively. For environmental samples spiking 3 different concentrations, the recovery values for the most targeted antiviral drugs ranged from 70 to 130%, except for efavirenz. All targeted antiviral drugs were detected in wastewater samples except for entecavir. We also found abacavir, efavirenz, ritonavir, lopinavir, and telbivudine in sediment and sludge samples. Notably, telbivudine was identified in all environmental matrices, with a high concentration of 127 ng L−1 and 222 ng g−1 in water and sediment samples, respectively. [Display omitted] • Easy and robust determination methods were developed for four environmental matrices. • Sensitive UPLC-MS/MS methods were developed to analyze 9 antiviral drugs. • The MQLs of antiviral drugs in environmental water ranged at 0.05–19.23 ng L−1. • Telbivudine was widely detected with the highest concentration up to 222 ng g−1 in sludge. [ABSTRACT FROM AUTHOR]

• Three modification TFCWs with baffle and plants were developed to treat PPCPs. • Efficient PPCPs removal was achieved in TFCW with baffle and plants. • Microbial degradation dominates the PPCPs removal by TFCWs. • Baffle and plants changed dominant microorganisms of substrates in TFCWs. • Thaumarchaeota is potentially responsible for PPCPs elimination in TFCWs. Research on decentralized wastewaters deserves special focus due to the potential abundance of emerging organic pollutants including pharmaceutical and personal care products (PPCPs), which might pose serious threats to the local water bodies and even to human health. Constructed wetland (CW) is a common decentralized wastewater treatment technology, with a certain ability to eliminate PPCPs. Nonetheless, PPCPs removal in common CWs is frequently challenging, besides, the removal mechanism remains elusive. Based on our previous study, tidal flow constructed wetlands (TFCWs) is effective in nitrogen removal. Here, 3 TFCWs with different modifications (baffle, plants, both baffle and plants) were constructed to treat raw domestic sewage and specifically to evaluate the removal efficiencies and mechanism of PPCPs. 24 PPCPs including 7 antibiotics, 8 steroid hormones and 9 biocides were detected in the level of 1.10 ± 0.29 ng/L-799 ± 10.6 ng/L in the influents. Consequently, we found that modification with both baffle and plants significantly influenced the removal of PPCPs. Moreover, the highest removal rates of biocides (97.1 ± 0.29%), steroid hormones (99.8 ± 0.02%), and antibiotics (90.2 ± 1.60%) were achieved via both baffles and plants in TFCWs. Based on the mass balance analysis, microbial degradation dominated the removal of PPCPs with a percentage higher than 85.7%, followed by substrate adsorption (5.22 × 10−2–14.3%) and plant uptake (1.66 × 10−3–0.44%). Further, 16S rDNA sequencing analysis revealed that the presence of baffle and plants improve the removal efficiency of PPCPs by means of enhancing microbial diversity and changing dominant microorganisms. Moreover, Thaumarchaeota was potentially the key microorganism in the phylum level for PPCPs elimination by TFCWs through LEfSe (linear discriminant analysis (LDA) effect size) analysis. These findings provide new insights into the removal of PPCPs in CWs. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• We investigated the fate of 40 steroid hormones in two swine farms. • 31 and 22 target steroids were detected in the wastewater and feces. • The two integrated WWTPs are effective in removing steroids. • The contribution of some steroids by sows was higher than byhumans. Steroid hormones are endocrine-disrupting chemicals that can cause adverse effects even at trace levels. The information about steroid hormones in animal wastes is still very limited. Here we investigated the occurrence and fate of fourteen androgens, twenty-one progestogens, and five glucocorticoids in Farm Luo Cheng (LC) and Farm Shui Tai (ST) with integrated wastewater treatment systems (WTSs) in South China. These two integrated systems have four stages: primary treatment (primary sedimentation tank), secondary biological treatment (biogas digester and up-flow anaerobic sludge reaction bed (UASB)), third-stage disinfection process, and fourth-stage dilution and further biodegradation process (oxidation fish ponds/lagoons). A total of 31 target steroid hormones were detected in the wastewater of the two swine farms, with concentrations ranging from 0.12 ng/L (medroxyprogesterone acetate, MPA) to 11,200 ng/L (5α-dihydroprogesterone, 5α-DHP). A total of 22 target steroid hormones were detected in feces, of which 19 were detected in Farm LC and 17 in Farm ST. Some of these detected steroids were synthetic chemicals, which might be parent chemicals from exogenous addition or their metabolites, or transformation products from other natural steroids. The steroids excretion of sows in swine farms were estimated, with some steroids such as androstenedione (AED, 41.5 μg/d), epiandrosterone (EADR, 268 μg/d), progesterone (P, 661 μg/d), and 5α-DHP (982μg/d) having much higher values than those from human bodies. Both WTSs in the swine farms could effectively remove the target steroid hormones, with the removal rates of most targets exceeding 90%. In comparison, the anaerobic digester-A2/O (anaerobic-anoxic-oxic)-lagoon system performed better in removing steroids than the up-flow anaerobic sludge reaction bed (UASB)-two-stage series (A/O)2-oxidation fish ponds system. However, there were still 22 steroid hormones, including 14 synthetic ones detected in the effluent, with the risk quotients of most synthetic steroids exceeding 1, showing high risks to aquatic organisms. The findings from this study showed that there is a wide presence of steroid hormones, especially some synthetic steroids in animal wastes, posing potential ecological risks, and these steroids should be removed before discharge to the environment. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Constructed wetland (CW) has been proved to be a reliable wastewater treatment technology for removal of various contaminants. However, the removal of specific contaminants such as steroid hormones by wetlands without optimized design parameters would be unstable. Here we investigated the removal mechanism of steroid hormones by constructed wetlands, and optimized various design parameters for the removal of these contaminants in wastewater. Four CW systems with different designs (artificial aeration or series wetland unit) were constructed outdoors to treat raw domestic sewage. The results showed that 9 steroid hormones were detected at concentrations from 7.13 ± 0.28 ng/L to 3040 ± 199 ng/L, with their removal rates ranged from 14.7 ± 3.04% to 100% by these CWs. It was also found that enhanced designs including aeration and series wetland unit can effectively improve the removal of steroid hormones. Combined with ecological risk assessment, CW4 (aerated VSSF CW and aerated HSSF CW combination) was the best design for removal of steroid hormones, but CW2 (VSSF CW with artificial aeration) may be better for urban areas with limited space. Based on mass balance calculation, biodegradation played a dominant role in removing steroid hormones by CWs, while substrate adsorption and plant uptake also played a limited role. The findings from this study suggest that CWs can be optimized to better remove steroid hormones in sewage before discharge into receiving environments. Unlabelled Image • We investigated removal of steroid hormones in domestic wastewater by CWs. • Optimized CWs can enhance removal of steroid hormones in domestic sewage. • Aeration and series wetland unit can significantly improve the treatment efficiency. • Microbial degradation is predominant for the removal of steroid hormones by CWs. • CWs treatment can reduce significantly the ecological risks of steroids. [ABSTRACT FROM AUTHOR]

Benzodiazepines (BZDs) are one of the most widely prescribed psychoactive drugs, however their persistence in the receiving environment has raised great concerns about their potential ecological risks. Here we investigated the occurrence, fate and mass loading of 17 BZDs and their 3 transformation products in 11 wastewater treatment plants (WWTPs) in Guangdong province, China. A total of 10 BZDs and 1 transformation product were found in the WWTPs influents, effluents and excess sludge, with concentrations reaching up to 44.5 ng/L (clozapine), 27.1 ng/L (oxazepam) and 62.9 ng/g (clozapine), respectively. The overall removal efficiency varied widely from negative to complete removal in these 11 WWTPs. Mass balance analysis of two representative WWTPs (WWTP A and WWTP B) with different treatment processes showed that their removals were mainly attributed to the sludge adsorption and biodegradation/biotransformation. The total usage of detected BZDs was estimated to be 185 kg/y in Guangdong province, China, while the total emission was 143 kg/y. Based on sewage epidemiology method, the total back-estimated consumption and emissions of BZDs and their transformation products in one district of Guangzhou (WWTP C service area) were 1012 mg/d/1000 people and 10.1 mg/d/1000 people, respectively. The findings from this study demonstrate the persistence of BZDs in WWTPs and also provide basis for further investigation into the potential ecological risks from this group of chemicals. Unlabelled Image • Benzodiazepines were frequently detected in 11 WWTPs in Guangdong. • Benzodiazepines cannot be efficiently removed in these WWTPs. • The estimated usage and emissions of benzodiazepines were 185 kg/y and 143 kg/y in Guangdong. • Clozapine, diazepam and estazolam are the most widely used compounds in WWTP C service area. [ABSTRACT FROM AUTHOR]

• UV/chlorine process dramatically enhanced the degradation of fluconazole. • Theoretical calculation was used to study the radical mediated degradation mechanism. • Six transformation products were identified by high resolution mass spectrometry. • The toxicity of reaction system decreased with only minor chloroform formation. The emerging organic contaminants can be effectively removed in the UV/chlorine process by produced hydroxyl radical (HO) and chlorine-derived radicals (Cl , ClO , etc.). However, the degradation mechanism and pathways of reactive radical reaction with contaminants are still unclear. Here we investigated the reactive radical mediated reaction kinetics and mechanism of fluconazole in UV/chlorine process using theoretical calculations and experimental studies. The results showed that fluconazole could be degraded effectively by UV/chlorine treatment than by UV photolysis and chlorination alone. The Cl and HO were found to play a major role in degradation of fluconazole by hydrogen atom transfer and radical adduct formation mechanisms, respectively. The single-electron transfer pathway of Cl , HO and ClO seems to be impossible due to the high free energy barriers of 21.87 kcal mol−1, 35.12 kcal mol−1 and 46.05 kcal mol−1, respectively. Six transformation products were identified by high resolution mass spectrometry and they were formed via fluconazole de-fluorination, hydroxylation, cleavage and cyclization with the triazole ring. The water quality parameters such as pH and coexisting components (DOM, HCO 3 −/CO 3 2−) could influence the removal of fluconazole in UV/chlorine process by impacting the generation of reactive radicals. The toxicity of fluconazole to aquatic organisms can be decreased by UV/chlorine process, and only trace amounts of chloroform were detected. [ABSTRACT FROM AUTHOR]

Animal waste fertilization is a traditional agricultural practice, which may have adverse effects to soil ecosystem. However, the side-effects of animal waste fertilization on vegetables are less studied. Here we selected a swine farming village for investigation with a nearby village without swine farming as comparison. In the swine farming village, the farmers use untreated swine manure and wastewater as fertilizers for vegetable cultivation. In the reference village, the farmers mainly use commercial organic fertilizers. The objective of this study is to assess the impacts of untreated swine waste fertilization on both soils and vegetables in terms of antibiotics, antibiotic resistance genes (ARGs) and bacterial microbial communities. The results indicate that untreated swine waste fertilization caused both antibiotic and ARG contaminations and changed the microbial community compositions in the soils. Varieties of tetracyclines and related resistance genes were detected especially in swine wastewater treated soils. The soil quality was impacted with the relations to bacterial abundances and microbial geochemical functions. Proteobacteria and Bacteroidetes were prevalent and positively correlated to ARGs in soils, indicating they were potential antibiotic resistant bacteria. Antibiotics and ARGs were detected in vegetables of both villages. The abundances of ARGs were relatively higher in some vegetable samples of the swine farming village than the reference village. In addition, intracellular parasites Rickettsiales with positive correlation to ARGs were prevalent in some vegetables of swine farming village, indicating potential health risks through eating contaminated vegetables. The results of this study suggest that untreated swine wastes may cause adverse effects to not only agricultural soils but also associated vegetables. Unlabelled Image • Swine wastewater released more antibiotics and ARGs than manure to soils. • Untreated swine wastes shifted both microbial community and function in soils. • Varieties of antibiotics and ARGs were detected in vegetables. • Rickettsiales were prevalent in some species of vegetables. • Consumption of the vegetables might pose risks to human health. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl substances (PFASs) are of particular environmental concern due to their environmental persistence and potential toxicity. Phytoremediation may be used to remove PFASs from wastewater. Here we investigated the uptake mechanism, subcellular distribution, and uptake process of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate acid (PFOS) in the wetland plant Alisma orientale by using a series of hydroponic experiments. Active uptake facilitated by water transporters and anion channels was involved in the uptake of PFASs by plant roots. PFOA and PFOS were mainly distributed in the water-soluble fraction (46.2–70.8%) and in cell walls (45.6–58.4%), respectively. The uptake process was proposed as follows: PFOS and PFOA were first distributed in the soluble fraction; a proportion of PFOS and PFOA were adsorbed gradually by the cell wall, and a proportion of PFOS and PFOA in the cell wall passed through the cell wall and plasmalemma and bind with organelles. PFOS and PFOA were transported from the external solution to the vascular bundle of the plant root through both symplastic and apoplastic routes. Unlabelled Image • Uptake of PFASs was an active process facilitated by transporters. • PFOA (PFOS) was mainly distributed in soluble components (cell walls). • Most of PFASs accumulated in root subcellular components were revisable. • PFASs in soluble fraction could be adsorbed by cell walls and bind with organelles. • PFASs could be transported through both symplastic and apoplastic routes. [ABSTRACT FROM AUTHOR]

Dissemination of antibiotic resistance genes (ARGs) in the water environment has become an increasing concern. There have been many reports on ARGs in surface water, but little is known about ARGs in groundwater. In this study, we investigated the profiles and abundance of ARGs in groundwater in comparison with those in surface water of Maozhou River using high-throughput quantitative PCR (HT-qPCR). Totally 127 ARGs and 10 MGEs were detected by HT-qPCR, and among them the sulfonamides, multidrug and aminoglycosides resistance genes were the dominant ARG types. According to the results of HT-qPCR, 18 frequently detected ARGs conferring resistance to 6 classes of antibiotics and 3 MGEs were further quantified by qPCR in the wet season and dry season. The absolute abundance ranged from 1.23 × 105 to 8.89 × 106 copies/mL in wet season and from 8.50 × 102 to 2.65 × 106 copies/mL in the dry season, with sul1 and sul2 being the most abundant ARGs. The absolute abundance of ARGs and MGEs has no significant difference between the wet season and dry season while the diversity of ARGs in the dry season was higher than that in the wet season (p < 0.05). Totally 141 and 150 ARGs were detected in the water and sediments of Maozhou River, respectively. A total of 116 ARGs were shared among the groundwater, river water, and sediment, which accounted for 67.1% of all detected genes. Redundancy analysis further demonstrated that the environmental factors contributed 70.7% of the total ARG variations. The findings of large shared ARGs, abundant Total Coliforms and large wastewater burden in the groundwater provide a clear evidence that anthropogenic activities had a significant impact on groundwater. Unlabelled Image • High-throughput qPCR was applied to screen ARGs and MGEs in groundwater. • Total Coliform and wastewater indicators were found in the groundwater. • The groundwater was an important reservoir of ARGs. • A large numbers of ARGs were shared among groundwater, river water and sediment. • Anthropogenic activities had a significant impact on groundwater. [ABSTRACT FROM AUTHOR]

• Swine farm wastewaters (SFWs) led to elevated steroid levels in the environment. • SFWs resulted in masculinization, defeminization and feminization in fish. • Steroid hormones in waters accounted for 53.4% of adverse effects in fish. • The adverse effects in fish from the ponds corroborated those from the rivers. Swine farm wastewaters (SFWs) are generally discharged either directly into nearby rivers or into fish ponds as a source of fertilizer/food for aquaculture in China. SFWs contain various contaminants including steroid hormones. However, there is an extreme paucity of data on their effects in fish populations. Here we investigated the endocrine disrupting effects of SFWs in G. affinis from 2 rivers (7 sites) and 2 fish ponds (2 sites) receiving SFWs and a reference site in Guangdong Province, China. In this study, a total number of 3078 adult western mosquitofish (Gambusia affinis) were collected and the sex ratio was determined. In addition, secondary sexual characteristics were examined and the transcriptional levels of target genes were analyzed. The results showed the mosquitofish populations had a significant increase in male-to-female ratio from 7 sites (including 2 fish ponds) among the 9 sampling sites. The hemal spines of females were masculinized at most sites while the hemal spines of males were feminized at approximately half of the sites (including 2 fish ponds). Significant reduction in vitellogenin (Vtg) mRNA expression was observed in females from 2 sites (including RS7) while elevated Vtg mRNA expression was noticed in males from 2 sites along the rivers (including RS7). Redundancy analysis showed that androgens in the water samples were closely related with male-to-female ratio in the mosquitofish populations and the masculinized hemal spines of females. The findings from this study demonstrated that discharge of SFWs could result in occurrence of both masculinized females and feminized males in mosquitofish population. [ABSTRACT FROM AUTHOR]

• Biodegradation of progestogens under oxic and anoxic conditions was investigated. • Degradation of PGT and DGT by swine wastewater-borne bacteria was investigated. • Natural progesterone was degraded more rapidly than synthetic progestogens. • Transformation products and pathways were proposed for PGT and DGT. • Hydroxylation, reduction and oxidation were involved in the degradation. Natural and synthetic progestogens in livestock environments have become a concern due to the frequent presence and potential adverse effects on aquatic organisms. Here we investigated the biotransformation of progestogens by wastewater-borne bacteria in the field and laboratory under oxic and anoxic conditions. The results showed that all progestogens dissipated faster under oxic conditions than under anoxic conditions, and natural progesterone transformed faster than synthetic progestogens. Meanwhile, dozens of bacterial strains capable of degrading progestogens were successfully isolated from the swine wastewater, and Bacillus sp. P19 and Bacillus sp. DGT2 were found the best for progesterone and dydrogesterone transformation, respectively. In the degradation experiments using a single bacterial strain, progesterone and dydrogesterone dissipated under oxic conditions with half-lives of 11.6 h and 18.2 h, respectively. The transformation pathways were proposed based on the identified transformation products. The findings from this study showed that progestogens can be biotransformed, but not fully mineralized in the environment. [ABSTRACT FROM AUTHOR]

Pharmaceutical plant sites play a significant role in the dissemination of antibiotic resistance genes (ARGs) into the environment. It is imperative to comprehensively monitor of ARGs across various environmental media at these sites. This study focused on three pharmaceutical plants, two located in North China and one in South China. Through metagenomic approaches, we examined the composition, mobility potential, and bacterial hosts of ARGs in diverse media such as process water, groundwater, topsoil, soil cores, and pharmaceutical fermentation residues across diverse environmental matrices, including topsoil, soil cores, process water, groundwater, and pharmaceutical fermentation residues. We identified a wide array of ARGs, comprising 21 types and 740 subtypes, with process water exhibiting the highest abundance and diversity. Treatment processes varied in their efficacy in eliminating ARGs, and the clinically relevant ARGs should also be considered when evaluating wastewater treatment plant efficiency. Geographical distinctions in groundwater ARG distribution between northern and southern regions were observed. Soil samples from the three sites showed minimal impact from pharmaceutical activity, with vancomycin-resistance genes being the most prevalent. High levels of ARGs in pharmaceutical fermentation residues underscore the necessity for improved waste management practices. Metagenomic assembly revealed that plasmid-mediated ARGs were more abundant than chromosome-mediated ARGs. Metagenome-assembled genomes (MAGs) analysis identified 166 MAGs, with 62 harboring multiple ARGs. Certain bacteria tended to carry specific types of ARGs, revealing distinct host-resistance associations. This study enhances our understanding of ARG dissemination across different environmental media within pharmaceutical plants and underscores the importance of implementing strict regulations for effluent and residue discharge to control ARG spread., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Environmental concentrations of antimicrobials can inhibit Cyanobacteria, but little is known about their effects on Cyanobacteria-blooming freshwater ecosystem. Here, a 21 days' outdoor freshwater mesocosm experiment was established to study effects of single and combined tetracycline, triclocarban and zinc at environmental concentrations on microbial community, microbial function and antimicrobial resistance using amplicon- and metagenomic-based methods. Results showed that three chemicals reshaped the microbial community with magnified effects by chemical combinations. Relative abundance of Cyanobacteria was decreased in all chemical groups, especially from 74.5 to 0.9% in combination of three chemicals. Microbial community networks were more simplified after exposure. Proteobacteria and Bacteroidetes predominated in Cyanobacteria-degraded ecosystems, and their relative abundances were significantly correlated with antibiotic resistome, suggesting that they might host antibiotic resistance genes. Notably, relative abundance (copy per 16 S rRNA gene) of total antibiotic resistome reached five to nine folds higher than the initial abundance in chemical-combined groups. The affected antibiotic resistance genes referred to a wide range of antibiotic classes. However, weak effects were detected on biocide/metal resistance and microbial virulence. Three chemicals posed complicated effects on microbial function, some of which had consistent variations across the groups, while some varied greatly in chemical groups. The findings highlight sensitivity of Cyanobacteria-blooming ecosystem to antimicrobials., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q) is an ozonation product of the rubber antioxidant N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD). 6PPD-Q has recently been detected in various environmental media, which may enter the human body via inhalation and skin contact pathways. However, the human metabolism of 6PPD-Q has remained unknown. This study investigated the in vitro Cytochrome P450-mediated metabolism of 6PPD-Q in human and rat liver microsomes (HLMs and RLMs). 6PPD-Q was significantly metabolized at lower concentrations but slowed at high concentrations. The intrinsic clearance (CL int ) of 6PPD-Q was 21.10 and 18.58 μL min -1  mg -1 protein of HLMs and RLMs, respectively, suggesting low metabolic ability compared with other reported pollutants. Seven metabolites and one intermediate were identified, and metabolites were predicted immunotoxic or mutagenic toxicity. Mono- and di-oxygenation reactions were the main phase I in vitro metabolic pathways. Enzyme inhibition experiments and molecular docking techniques were further used to reveal the metabolic mechanism. CYP1A2, 3A4, and 2C19, especially CYP1A2, play critical roles in 6PPD-Q metabolism in HLMs, whereas 6PPD-Q is extensively metabolized in RLMs. Our study is the first to demonstrate the in vitro metabolic profile of 6PPD-Q in HLMs and RLMs. The results will significantly contribute to future human health management targeting the emerging pollutant 6PPD-Q., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

To understand the contamination characteristics and ecological risk of antibiotics in contaminated fields of pharmaceutical plants， samples of the surface soil， soil column， wastewater treatment process water， ground water， and residue dregs were collected from two typical antibiotic pharmaceutical plants in South and North China. A total of 87 commonly used antibiotics were quantified using ultrasound extraction-solid phase extraction and ultra-high performance liquid chromatography-mass spectrometry. The results showed that a total of 31 antibiotics of five classes were detected in all types of samples， and the maximum concentrations at each sampling point in the surface soil， soil column， residue dregs， wastewater treatment process water， and groundwater were 420 ng·g -1 ， 595 ng·g -1 ， 139 ng·g -1 ， 1 151 ng·L -1 ， and 6.65 ng·L -1 ， respectively. Most of the antibiotics were found in the surface soil， showing a decreasing trend with the depth of the soil column. The ecological risk assessment indicated that sulfamethazine， sulfaquinoxaline， tetracycline， chlorotetracycline， and D-sorbitol were at higher risk. Improving the efficiency of antibiotic removal from pharmaceutical wastewater and preventing production shop leaks are effective measures of controlling antibiotic contamination into and around fields in pharmaceutical plants.

In the past decade, organophosphate esters (OPEs) undergo rapid increase in production and use. Meanwhile, owing to their additive property, OPEs exhibit liability to escape from related products and therefore ubiquity in various environments. Moreover, numerous researches verify their bioavailability and negative effects on biota and human, hence their occurrence and associated risks have caught much concern, particularly those in aquatic systems. So far, however, OPEs in water are generally investigated as a whole, their phase distribution and behavior in waterbodies are incompletely characterized. We examined 25 OPEs in water (including dissolved and particulate phases), sediment, and sediment core samples from the Lian River, which flows through the Guiyu e-waste recycling zone and Shantou specific economic zone in South China. Compared to most global waterbodies, the Lian River showed high or ultrahigh OPE levels in both water and sediments, particularly in the reaches surrounded by e-waste recycling and plastic-related industries, which were the top two greatest OPE sources. Non-industrial and agriculture-related anthropogenic activities also contributed OPEs. Sediment core data suggested that OPEs have been present in waters in Guiyu since the 1960s and showed a temporal trend consistent with the local waste-recycling business. The phase distribution of OPEs in the Lian River was significantly correlated with their hydrophobicity and solubility. Owing to their wide range of physicochemical properties, OPE congeners showed significant percentage differences in the Lian River water and sediments. Generally, OPEs in water reflect their dynamic real-time inputs, while those in sediment signify their accumulative deposition, which is another cause of their phase distribution disparities in the Lian River. The physicochemical parameters of OPEs first imposed negative and then positive influences on their dissolved phase-sediment distribution, indicating the involvement of both the adsorption of dissolved OPEs and the deposition of particle-bound OPEs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Many organic chemicals are present in aquatic environments, but how to screen and prioritize these chemicals has always been a difficult task. Here we investigated organic chemicals in the West River Basin by using a developed non-target identification workflow. A total of 957 chemicals were tentatively identified, with 96 assigned as high confidence levels by matching with reference standards, MassBank spectral library, and using CompTox Chemistry Dashboard database as the compound library for MetFrag. More pesticides and their transformation products (e.g., metolachlor ESA, acetochlor ESA, deethylatrazine, and hydroxyatrazine) were detected in the wet season due to the increasing usage. High detection of pharmaceutical and personal care products and their transformation products in the tributaries was linked to rural farming and human activities. Irbesartan that is used to treat high blood pressure was recognized in the river and positive correlations between some detected chemicals and irbesartan were observed, indicating a domestic wastewater source. Ecological risks of the identified chemicals were calculated by toxicological prioritization ranking schemes, and 24 chemicals showed high ToxPi scores in the river. The results from this study show the presence of a large number of emerging organic chemicals in our waterways, and demonstrated conceptual schemes for integrating risk assessment into a non-target screening workflow., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Acinetobacter is present in the livestock environment, but little is known about their antibiotic resistance and pathogenic species in the farm groundwater. Here we investigated antibiotic resistance of Acinetobacter in the swine farm groundwater (JZPG) and residential groundwater (JZG) of a swine farming village, in comparison to a nearby (3.5 km) non-farming village (WTG) using metagenomic and culture-based approaches. Results showed that the abundance of antibiotic resistome in some JZG and all JZPG (~3.4 copies/16S rRNA gene) was higher than that in WTG (~0.7 copies/16S rRNA gene), indicating the influence of farming activities on both groundwater types. Acinetobacter accounted for ~95.7% of the bacteria in JZG and JZPG, but only ~8.0% in WTG. They were potential hosts of ~95.6% of the resistome in farm affected groundwater, which includes 99 ARG subtypes against 23 antibiotic classes. These ARGs were associated with diverse intrinsic and acquired resistance mechanisms, and the predominant ARGs were tetracyclines and fluoroquinolones resistance genes. Metagenomic binning analysis elucidated that non-baumannii Acinetobacter including A. oleivorans, A. beijerinckii, A. seifertii, A. bereziniae and A. modestus might pose environmental risks because of multidrug resistance, pathogenicity and massive existence in the groundwater. Antibiotic susceptibility tests showed that the isolated strains were resistant to multiple antibiotics including sulfamethoxazole (resistance ratio: 96.2%), levofloxacin (42.5%), gatifloxacin (39.0%), ciprofloxacin (32.6%), tetracycline (32.0%), doxycycline (29.0%) and ampicillin (12.0%) as well as last-resort polymyxin B (31.7%), colistin (24.1%) and tigecycline (4.1%). The findings highlight potential prevalence of groundwater-borne antibiotic-resistant pathogenic Acinetobacter in the livestock environment., (© 2023. The Author(s).)

As the nexus where rivers and oceans meet, estuaries are vulnerable to microplastic (MP) pollution derived from rivers. However, few studies have focused on the pollution status of MPs in small estuarine areas. Here, the abundance and characteristics of MPs in surface water and sediment samples from a small estuary, the Wanquan River estuary, were studied. The average abundance of MPs was 6573 ± 2659 n/m 3 in surface water and 1065 ± 696 n/kg dw in sediment samples from the Wanquan River estuary. Most of the MPs in water samples and sediments were red (92.9 % and 88.1 %) fragments (87.4 % and 95.5 %) with sizes <1.0 mm (90.8 % and 92.4 %) made up of antifouling paint particles (APPs) (83.5 % and 89.8 %), respectively. A significant positive correlation (p < 0.01) was found between the concentration of Cu 2+ and the abundance of APPs in sediment samples from the Wanquan River estuary. The APPs in the sediments can act as a continuous source of toxic chemicals (e.g., Cu 2+ ) to marine environments. The results of this study expand our knowledge about MP pollution in small estuaries, and the ecological risk of APPs in the Wanquan River estuary to aquatic organisms should not be ignored., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

As a class of common emerging pollutants, per- and polyfluoroalkyl substances (PFASs) and their alternatives have been widely detected in various environmental matrices, exhibiting a great threat to the ecological environment and human health. Nevertheless, changes in biomolecular structure and function of duckweed caused by PFASs and their alternatives remain unknown thus far. Herein, the effects of four PFASs, including two common legacy PFASs (perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA)) and two PFASs alternatives (perfluorobutane sulfonic acid (PFBS) and 1H,1H,2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)) on duckweed (Lemna minor) at biochemical level were investigated with Fourier transform infrared spectroscopy (FTIR). Although no obvious inhibitions were observed in the growth of L. minor with PFASs exposure at three levels of 1 μg L -1 , 100 μg L -1 , and 10 mg L -1 , significant structural and functional alterations were induced at the biochemical level. In response to PFASs exposure, lipid peroxidation, proteins aggregation and α-helix to β-sheet transformation of the protein conformation, as well as changes of DNA conformations were detected. Moreover, alterations in lipid, protein, and DNA were proved to be concentration-related and compound-specific. Compared to the two legacy PFASs (PFOS and PFOA), alternative ones exhibited greater effects on the biological macromolecules of L. minor. The findings of this study firstly reveal structural and functional alterations in L. minor induced by PFASs exposure, providing further understanding of their toxicity effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Emission of antibiotics into riverine environments affects aquatic ecosystem functions and leads to the development of antibiotic resistance. Here, the profiles of forty-four antibiotics and eighteen antibiotic resistance genes (ARGs) were analyzed in two large rivers of the Pearl River System. In addition, the risks of ecotoxicity and resistance selection posed by the antibiotics were estimated. As compared to the reservoirs, the river sections close to the urban and livestock areas contained more antibiotics and ARGs. Seasonal variations of antibiotics (higher in the dry season) and relative ARGs (normalized by 16S rRNA gene, higher in the wet season) were found in the water, but not in the sediment. Sulfonamide resistance genes were the most prevalent ARGs in both river water and sediment. Antibiotic concentration was correlated with ARG abundance in the water, indicating that antibiotics play a critical role in ARG spread. In addition, oxytetracycline was the most abundant antibiotic with concentrations up to 2030 ng/L in the water and 2100 ng/g in the sediment respectively, and posed the highest risks for resistance selection. Oxytetracycline, tetracycline and sulfamethoxazole were expected to be more ecotoxicologically harmful to aquatic organisms, while ofloxacin, enrofloxacin, norfloxacin, chlortetracycline, oxytetracycline and tetracycline posed ecotoxicological risks in the sediment. The Nanliujiang river with intensive livestock activities was contaminated by antibiotics and ARGs and faced high ecotoxicological and resistance selection risks. Collectively, these findings reflect the impacts of anthropogenic activities on the spread of antibiotic resistance in large river basins., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Antibiotic resistance genes (ARGs) pose a serious threat to environmental biology and public health, along with the discharge and spread of wastewater. The advanced treatment of ARGs in wastewater therefore deserves special attention. In our previous study, we found that tidal flow constructed wetlands can effectively remove multiple ammonia from wastewater. In this study, we further optimized tidal flow constructed wetland systems by adding baffles and cultivating plants; we investigated the influence of process optimization on the removal of ARGs and the influence of functional microorganism distribution on nitrogen removal. The results show that the addition of baffles and plants can effectively improve the removal efficiency of ARGs, with the maximum removal rate of 21 resistance genes, in 7 categories, reaching 83.82%-100.0% with the simultaneous addition of baffles and plants. These removal rates were significantly higher than the increase resulting from a single baffle or plant group. From the comparison of the absolute abundance of ARGs in the substrate and plants, it is clear that the baffles can promote the enrichment of ARGs in the wetland substrate, while uptake by plants is also a way of removing ARGs. Combined with the results of nitrogen-cycle functional gene sequencing, system optimization can increase the diversity and richness of nitrification and denitrification functional microorganisms in the substrate, which is consistent with the higher removal rate of nitrification and total nitrogen in wastewater.

As an alternative to volatile organic solvents, ionic liquids (ILs) are known as "green solvents", and widely used in industrial applications. However, due to their high solubility and stability, ILs have tendency to persist in the water environment, thus having potential negative impacts on the aquatic ecosystem. For assessing the environmental risks of ILs, a fundamental understanding of the toxic effects and mechanisms of ILs is needed. Here we evaluated the cytotoxicity of 1-methyl-3-decylimidazolium chloride ([C 10 mim]Cl) and elucidated the main toxic mechanism of [C 10 mim]Cl in human cervical carcinoma (Hela) cells. Microstructural analysis revealed that [C 10 mim]Cl exposure caused the cell membrane breakage, swollen and vacuolated mitochondria, and spherical cytoskeletal structure. Cytotoxicity assays found that [C 10 mim]Cl exposure increased ROS production, decreased mitochondrial membrane potential, induced cell apoptosis and cell cycle arrest. These results indicated that [C 10 mim]Cl could induce damage to cellular membrane structure, affect the integrity of cell ultrastructure, cause the oxidative damage and ultimately lead to the inhibition of cell proliferation. Moreover, alterations of biochemical information including the increased ratios of unsaturated fatty acid and carbonyl groups to lipid, and lipid to protein, and the decreased ratios of Amide I to Amide II, and α-helix to β-sheet were observed in [C 10 mim]Cl treated cells, suggesting that [C 10 mim]Cl could affect the structure of membrane lipid alkyl chain and cell membrane fluidity, promote the lipid peroxidation and alter the protein secondary structure. The findings from this work demonstrated that membrane structure is the key target, and membrane damage is involved in [C 10 mim]Cl induced cytotoxicity., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Domestic wastewaters are an important source of endocrine disrupting chemicals in the receiving aquatic environment. Most rural domestic wastewaters (RDWs) in China have been directly discharged into the aquatic environment without any treatment. Here we studied the effects of RDWs on the western mosquitofish (Gambusia affinis) from two rural rivers receiving untreated RDWs. Mosquitofish samples were collected at 5 sampling sites along two rivers during dry and wet seasons. Sex ratios, secondary sex characteristics and transcriptional levels of target genes related to the endocrine system in adult females and males were determined. In parallel, various pollutants including steroid hormones, phenolic compounds, pesticides, polycyclic aromatic hydrocarbons (PAHs) and heavy metals were measured in the water samples at all sites. The results showed that the androgenic effects in the fish were evidenced by significant increase in male to female ratio in fish populations at two sampling sites and by the presence of modified hemal spines in females at four sampling sites when compared to the reference site. The males from the two rivers had increased Vtg mRNA expressions with a maximal 6.2-fold increase relative to the reference site and a delayed development of hemal spines. The redundancy analysis (RDA) showed that some physiological parameters were related to steroid hormones, phenolic compounds and PAHs. The findings from this study suggest that RDWs can lead to masculinization in females and feminization in males., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This study measured the concentrations of six N -nitrosamines (NAs) in water samples from each process stage of three wastewater treatment plants (WWTPs) and their corresponding receiving rivers. The occurrence and removal of NAs was then systematically studied in three WWTPs using different treatment processes, and their pollution profiles and sources in the receiving rivers were analyzed. The results showed that the six NAs occurred widely in the wastewater from every process stage of three WWTPs. NPIP, NDMA, and NPYR were the dominant pollutants with concentrations in the tens to hundreds ng·L -1 . The three WWTPs using different treatment processes removed a certain amount of NAs, and the modified A 2 /O and A 2 /O+MBR showed good NAs removal effects, with total removal rates of 95% and 63%, respectively. The removal of NAs mainly relied on microbial degradation and transformation during the biochemical stage. During the filtration, disinfection, and MBR stages, NAs precursors in the wastewater treatment system could form some added NAs after a series of reactions. The six NAs were also frequently detected in the surface waters of receiving rivers, where the main pollutants were also MDMA, NPIP, and NPYR, which was consistent with the influent of the WTTPs. The sources of NAs in the receiving rivers were wide ranging and complicated, including emission from the effluent of the WTTPs, the release of untreated sanitary sewage, industrial wastewater, and surface runoff from industrial districts. Therefore, effective measures should be taken to reduce the input of NAs into receiving rivers, such as enhancing the capacity of sewage collection and treatment and optimizing sewage treatment processes.

Hybrid design and artificial aeration has been widely applied in wetlands, but little is known about their effectiveness in the removal of antibiotics and antibiotic resistance genes (ARGs). Here we investigated the performance of various mesocosm-scale constructed wetlands (CWs) with artificial aeration and hybrid design in removal of antibiotics and ARGs from antibiotics-spiked domestic sewage. Four hybrid constructed wetland systems with zeolite as substrate and Iris tectorum Maxim as plant were set up to have different artificial aeration designs. The aqueous removal efficiencies of total antibiotics ranged from 87.4% to 95.3%, while those of total ARGs varied from 87.8% to 99.1%. The mass removal of antibiotics by the CWs was attributed mainly to the microbial degradation. The present study imply that sorption of substrates and biological processes could be the two main mechanisms for ARGs elimination. The results from this study showed the hybrid CWs with artificial aeration could enhance treatment efficiencies of antibiotics and ARGs as well as conventional pollutants., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Benzotriazoles (BTs) are a group of heterocyclic compounds which have been widely applied in industrial activities and domestic life mainly as corrosive inhibitors. BTs have been ubiquitously detected in receiving environments and cause potential toxicity to non-target organisms. This paper reviews the occurrence and fate of six selected benzotriazole compounds in different environmental and biological matrices, as well as the transformation and toxicity. Due to their high hydrophilicity and insufficient removal in wastewater treatment plants (WWTPs), these compounds were widely detected in aquatic environments with concentrations mainly from tens ng/L to tens μg/L. Considerable residual levels of BTs in plant, fish, air, tap water and human urine have implied the potential risks to various organsims. The reported acute toxicity of BTs are generally low (EC 50 in mg/L level). Some observed sublethal effects including endocrine disrupting effects, hepatotoxicity and neurotoxicity, as well as the ability to promote the development of endometrial carcinoma still raise a concern. BTs are found often more recalcitrant to biodegradation compared to photolysis and ozonation. Environmental factors including pH, temperature, irradiation wavelength, redox condition as well as components of matrix are proved crucial to the removal of BTs. Further studies are needed to explore the precise environment fate and toxicity mechanism of BTs, and develop advanced treatment technologies to reduce the potential ecological risks of BTs., (Copyright © 2019. Published by Elsevier B.V.)

Steroid hormones and biocides are regarded as emerging contaminants in rural wastewater in China, owing to their widespread occurrence and adverse effects on both aquatic organisms and humans. Constructed wetlands (CWs) are an alternative technology for cost-effective and efficient decentralized rural sewage treatment. In this study, an integrated constructed wetland (ICW) system was built and used to treat a typical rural wastewater mixture composed of domestic sewage and livestock wastewater from a small village. As expected, five steroid hormones (ADD, AED, 19-NTD, T, and P) and four biocides (DEET, TCS, CBD, and MP) were detected in the influent in concentrations ranging from 30.5 ± 1.25 ng/L to 105 ± 5.14 ng/L and from 63.4 ± 2.85 ng/L to 515 ± 19.7 ng/L, respectively. The ICW system effectively removed the detected steroid hormones (97.4 ± 0.09%) and biocides (92.4 ± 0.54%). Based on the measured concentrations, the total pollution loadings of the detected steroid hormones and biocides in the influent were calculated to be 2330 ± 26.5 μg/day and 5710 ± 196 μg/day, which decreased to 60.8 ± 1.44 μg/day and 433 ± 25.6 μg/day in the final effluent. The risk quotients for these steroid hormones and biocides in the effluent from the ICW system were lower than those from reported wastewater treatment plants, indicating that CWs are a promising technology for removing contaminants including steroid hormones and biocides in rural wastewater, although additional efforts are required to optimize and improve the design of CWs before the steroid hormones and biocides present in the effluent can be safely and directly discharged into the environment., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Antibiotics are widely applied in livestock industry to prevent or treat animal diseases. However, those antibiotics are poorly metabolized in livestock animals, most of them being excreted via feces or urine. Hence we need to understand the removal of antibiotics in swine farm wastewater treatment systems. This study investigated occurrence and fate of various antibiotics in two full-scale swine farm wastewater treatment systems (Farm A: anaerobic digester-A 2 /O-lagoon; Farm B: upflow anaerobic sludge blanket (UASB)-(A/O) 2 -lagoon). The results showed the presence of 25 antibiotics out of 40 target antibiotics in the wastewater and sludge samples from the two farms. In Farm A, sulfamonomethoxine, sulfachlorpyridazine, oxytetracycline and lincomycin were predominant in the influent with concentrations up to 166 ± 3.64 μg/L, while in the dewatered sludge chlortetracycline, oxytetracycline, tetracycline and norfloxacin were the predominant target compounds with concentrations up to 29.2 ± 3.74 μg/g. In Farm B, high concentrations (up to 3630 ± 1040 μg/L) of sulfachlorpyridazine, sulfamonomethoxine and lincomycin were detected in the influent, and the predominant target antibiotics detected in the dewater sludge were similar to those in Farm A, with concentrations up to 28.6 ± 0.592 μg/g. The aqueous removal rates for the total antibiotics were >99.0% in the wastewater treatment plants of both farms. Among a series of treatment units, the anaerobic digester in Farm A and UASB in Farm B made a significant contribution to the elimination of the target antibiotics from the animal wastewater. The daily mass loadings of total antibiotics in the manure, influent, dewatered sludge and effluent were 17.1, 28.0, 2.53, and 0.0730 g/d for Farm A and 24.5, 354, 3.17, and 0.293 g/d for Farm B. The full-scale swine wastewater treatment facilities could effectively remove antibiotics from swine wastewater, but the dewatered sludge needs to be further treated before disposal on land., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Aim: To explore the associations of polymorphisms of lipopolysaccharide binding protein (LBP), cluster of differentiation 14 (CD14), toll-like receptor 4 (TLR-4), interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) with the colorectal carcinoma (CRC) risk in Han Chinese., Methods: Polymorphisms of LBP (rs1739654, rs2232596, rs2232618), CD14 (rs77083413, rs4914), TLR-4 (rs5030719), IL-6 (rs13306435) and TNF-α (rs35131721) were genotyped in 479 cases of sporadic colorectal carcinoma and 486 healthy controls of Han Chinese in a case-control study. Single-nucleotide polymorphisms (SNPs) between cases and controls were analyzed by unconditional logistic regression., Results: GA and GG genotypes of LBP rs2232596 were associated with a significantly increased risk of CRC [odds ratio (OR) = 1.51, 95% confidence interval (CI) 1.15-1.99, P = 0.003; OR = 2.49, 95% CI 1.16-5.38, P = 0.016, respectively]. A similar association was also observed for the CG genotype of CD14 rs4914 (OR= 1.69, 95% CI 1.20-2.36, P = 0.002). In addition, a combination of polymorphisms in LBP rs2232596 and CD14 rs4914 led to a 3.4-fold increased risk of CRC (OR = 3.44, 95% CI 1.94-6.10, P = 0.000)., Conclusion: This study highlights the LBP rs2232596 and CD14 rs4914 polymorphisms as biomarkers for elevated CRC susceptibility in the Chinese Han population.

Objective: To investigate the related factors of portal vein tumor thrombosis (PVTT) in patients with HCC., Methods: A total number of 234 patients with hepatocellular carcinoma (HCC) were included in this retrospective study. Uni-variate and multi-variate logistic regression analysis were employed to analyze the association between PVTT and 18 routine clinical parameters., Results: Among the 234 patients with HCC, 15% of patients (35/235) had PVTT. Univariate logistic regression analysis revealed significant association of age (P = 0.016), gamma glutamyl transferase (GGT, P = 0.003), number of segmental invasion (P = 0.007), microvascular invasion (P < 0.01), segment location of S2 (P = 0.001), S3 (P = 0.000), S4 (P = 0.004) and S6 (P = 0.016). Multivariate analysis shows potential significant predictors of PVTT in HCC were age (RR: 0.373; 95% CI: 0.146-0.954; P = 0.040), the tumor location of S3 (RR: 4.625; 95% CI: 1.916-11. 165;P = 0.001), GGT (RR: 4.091; 95% CI: 1.448-11.553; P = 0.008) and microvascular invasion (RR: 20.912; 95% CI: 4.745-92.172; P < 0.01)., Conclusions: PVTT occurred more commonly in the younger (< 50 years old), and those with high level of GGT, segment location of S3 and microvascular invasion.