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Hospital wastewater contains a variety of human antibiotics and pathogens, which makes the treatment of hospital wastewater essential. However, there is a lack of research on these pollutants at hospital wastewater treatment plants. In this study, the characteristics and removal of antibiotics and antibiotic resistance genes (ARGs) in the independent treatment processes of hospitals of different scales (primary hospital, H1; secondary hospital, H2; and tertiary hospital, H3) were investigated. The occurrence of antibiotics and ARGs in wastewater from three hospitals varied greatly. The first-generation cephalosporin cefradine was detected at a concentration of 2.38 μg/L in untreated wastewater from H1, while the fourth-generation cephalosporin cefepime had the highest concentration, 540.39 μg/L, at H3. Ofloxacin was detected at a frequency of 100% and had removal efficiencies of 44.2%, 51.5%, and 81.6% at H1, H2, and H3, respectively. The highest relative abundances of the β-lactam resistance gene blaGES-1 (1.77×10−3 copies/16S rRNA), the quinolone resistance gene qnrA (8.81×10−6 copies/16S rRNA), and the integron intI1 (1.86×10−4 copies/16S rRNA) were detected in the treated wastewater. The concentrations of several ARGs were increased in the treated wastewater (e.g. blaOXA-1, blaOXA-10, and blaTEM-1). Several pathogenic or opportunistic bacteria (e.g. Acinetobacter, Klebsiella, Aeromonas, and Pseudomonas) were observed at high relative abundances in the treated wastewater. These results suggested the co-occurrence of antibiotics, ARGs, and antibiotic-resistant pathogens in hospital wastewater, and these factors may spread into the receiving aquatic environment. Supplementary Information The online version contains supplementary material available at 10.1007/s11356-021-14735-3.

Due to low consumption and high efficiency, in situ microbial remediation of petroleum hydrocarbons (PHs)-contaminated sites in in-service petrochemical enterprises has attracted more and more attention. In this study, a degrading strain was isolated from oil depot-contaminated soil with soil extract (PHs) as the sole carbon source, identified and named Rhodococcus sp. OBD-3. Strain OBD-3 exhibited wide adaptability and degradability over a wide range of temperatures (15-37 °C), pH (6.0-9.0), and salinities (1-7% NaCl) to degrade 60.6-86.6% of PHs. Under extreme conditions (15 °C and 3-7% salinity), PHs were degraded by 60.6 ± 8.2% and more than 82.1% respectively. In OBD-3, the alkane monooxygenase genes alkB1 and alkB2 (GenBank accession numbers: MZ688386 and MZ688387) were found, which belonged to Rhodococcus by sequence alignment. Moreover, strain OBD-3 was used in lab scale remediation in which the contaminated soil with OBD-3 was isolated as the remediation object. The PHs were removed at 2,809 ± 597 mg/kg within 2 months, and the relative abundances of Sphingobium and Pseudomonas in soil increased more than fivefold. This study not only established a system for the isolation and identification of indigenous degrading strains that could efficiently degrade pollutants in the isolated environment but also enabled the isolated degrading strains to have potential application prospects in the in situ bioremediation of PHs-contaminated soils.

Various pollutants remaining in the livestock and poultry manures pose potential threat to the soil ecosystem during land application, whose impact should be appreciated. The occurrence of heavy metals, antibiotics, and antibiotic resistance genes (ARGs) in swine manure (SM), chicken manure (CM), and the SM organic fertilizer (OF) were investigated. The order of total concentrations of antibiotics detected in manures was as follows: SM > CM > OF. The amount of ciprofloxacin (CIP) in SM reached up to 6.61 mg/kg, which only occupied 1% of the antibiotic concentration reported in the past years. The total concentration of thirteen ARGs in CM ranked first, reaching 7.35 × 1011 copies/g, among which the strB gene was detected with the highest concentration. It was worth noting that the qnr ARGs were persistent in OF with the absence of corresponding antibiotics, indicating ARGs were harder to remove than antibiotics during manure composting. Zn and Cu (46.5-843 mg/kg) were obviously higher than other seven heavy metals, and significantly correlated with most ARGs (p < 0.01). This study provided the basic data of the pollution in animal manures that will be land-applied, illuminating the original source of potential risk in soil ecosystem.

The iron and nickel bimetallic nanoparticles supported by the block copolymer polystyrene-block-poly (acrylic acid) (PS-b-PAA-nZVI-Ni) were synthesized successfully and were applied to assess the degradation of 1,1,1-trichloroethane (1,1,1-TCA) in water. An optimal dose of Ni loading was 2 wt%, while an optimal mass ratio of PS-b-PAA to Ni/Fe, i.e., 0.5:1, at which the dechlorination efficiency was a maximum. The size of PS-b-PAA-nZVI-Ni nanoparticles (average size ~ 50 nm) was three times smaller than that of nZVI-Ni due to the prevention of agglomeration of the resultant zerovalent iron nanoparticles by PS-b-PAA. In the applying aspect, the pseudo-first-order rate constant (Kobs) of 1,1,1-TCA removal by PS-b-PAA-nZVI-Ni was 0.0142 min-1 within 240 min, which was approximately five times higher than nZVI. Meanwhile, PS-b-PAA-supported nZVI-Ni nanoparticles penetrated much deeper in quartz sand columns than nZVI-Ni nanoparticles, indicating PS-b-PAA had significant influence on nZVI transport. The findings from this study suggested that PS-b-PAA-nZVI-Ni, with its high reactivity, selective screening for 1,1,1-TCA, could be one significant potential for use as remedial agent to treat chlorinated solvents in water.

The excessive dissemination of New Delhi metallo-β-lactamase-1 (NDM-1), which mediates resistance to a majority of clinical β-lactam antibiotics, has created a major public health problem worldwide. Herein, a bla

Heterogeneous Fenton has emerged as a profitable solution for contaminant removal via advanced oxidation processes (AOPs). Besides the dominant hydroxyl radicals (HO•), some weaker oxidants, such as ferryl-oxo species (Fe(IV)=O) species, can also be produced during the surface H2O2 activation, but its function is not well understood. In this study, we developed a vanadium-etched iron oxychloride (V-FeOCl) catalyst that simultaneously incorporates Fenton-like sites and peroxidase-like (Fe(IV)=O) sites. The derived V-FeOCl material showed 2.8-5.4 times enhancement of the pseudo-first-order rate constant for various recalcitrant organic micropollutants. Most importantly, the activity demonstrated an intriguing induction period for the TOC removal as well as a rocketed kinetics after the induction. This induction period was further attributed to the oxidative coupling of the organic monomers, as revealed by the identification of dimers using UPLC-MS. The coupling intermediates were demonstrated to be more susceptible to HO• radical attack via the high-throughput prediction of the HO• radical rate constants of 94 possible coupling intermediates using machine learning. These findings clarified the key role of Fe(IV)=O in the HO•-based oxidation process and points to a novel coupling-enhanced degradation pathway, which could potentially pave a new avenue of oxidative transformations for catalytic and environmental applications.

Environmental antibiotics raise serious health concerns due to their contribution to the obesity prevalence. Moreover, antibiotics promote antibiotic-resistance bacteria (ARB) which represent another emerging pollutant. However, the interaction between antibiotic and ARB in the obesogenic effects remained unexplored. In the present study, the obesogenic effects of tetracycline antibiotic (TCH) and ARB containing tetA were studied on C. elegans, and E. coli OP50 (OP50) was referred as a normal bacterial food. Results showed that TCH stimulated nematode triglyceride contents, while ARB alone had no significant influences. The combination of TCH and ARB showed less obesogenic effects than TCH alone, showing antagonism. Biochemical assays showed that the combination of TCH and ARB showed similar effects to ARB alone, and had less increases in lipid metabolism enzymes or metabolites than those of TCH or ARB alone, supporting the antagonism. In the nontargeted metabolomic analysis, TCH with ARB showed less significantly changed metabolites (SCMs) in the nematodes than TCH or ARB alone, partially explaining the antagonism. The metabolomic results also pointed out the significant involvement of amino acids, the carboxylic acids and derivatives, and also the benzene and substituted derivatives in the obesogenic effects of TCH and ARB. The findings of the present study provided a direct support for interaction between antibiotics and ARB underlying their health risks.

Heavy metal exposure via food consumption is inadequately investigated and deserves considerable attention. We collected hundreds of food ingredients and daily meals and assessed their probabilistic health risk using a Monte Carlo simulation based on an ingestion rate investigation. The detected concentrations of four heavy metals (Cr, Cd, Pb, and Hg) in all daily meal samples were within the limits stipulated in the National Food Safety Standard (GB 2762-2017), while that for As level was excessive in 0.3 % of daily meal samples. The same results were also observed in most food ingredient samples, and a standard-exceeding ratio of 23 % of As was observed in aquatic food or products, especially seafood, which was with the highest concentration reaching 1.24 mg/kg. Combining the detected heavy metal amounts with the ingestion rate investigation, the hazard quotients (HQs) of As, Cr, Cd, Pb, and Hg in daily meals and food ingredients were all calculated as lower than 1 (no obvious harm), while the incremental lifetime cancer risk (ILCR) of As and Cr (1 × 10

Arsenic and antimony are common toxic metalloids found in associated minerals. These metalloids generally cause high-concentration pollution in non-ferrous metal smelting soils; however, few studies have investigated the pollution characteristics of these two metalloids at non-ferrous smelting sites using varying soil particle sizes. In this study, the valency distributions and geochemical fractions were investigated with varying soil particle sizes (≤ 0.05, 0.05-0.25, 0.25-1, and 1-2 mm). Soils were mainly concentrated in ≤ 0.05 and 0.05-0.25 mm with mass percentages of 32.97% and 29.02%, respectively. The highest total As and Sb concentrations in ≤ 0.05 mm were found to be 20,350 and 3655 mg/kg, respectively. In addition, As(Ⅲ), As(Ⅴ), Sb(Ⅲ), and Sb(Ⅴ) concentrations in this soil particle size were found to be 224, 19,813, 1036, and 24 mg/kg, respectively. The geochemical fractions of As and Sb in varying soil particle sizes were mainly residual, accounting for 50% and 90% in the ≤ 0.05 mm. Soil may bind ≤ 0.25 mm due to the disparity found in the geochemical compositions and valency distributions of arsenic and antimony. X-ray diffraction and scanning electron microscopy/energy dispersive system analysis confirmed that arsenolite accumulated in particle sizes of ≤ 0.05 and 0.05-0.25 mm. The results of this study may provide a scientific reference for risk assessment and restoration strategies for non-ferrous metal smelting soils.

Water pollution caused by organic pollutants and pathogenic microorganism is a critical issue. In this study, we reported a silver-modified β-cyclodextrin polymer (CD-CA/PDA-Ag) used for the removal of dyes and the suppression of microorganisms from water. In order to avoid silver nanoparticles agglomeration, the material was first coated with polydopamine (PDA) on β-cyclodextrin matrix, whose reducing catechol groups subsequently immobilized silver ions in situ to form uniformly dispersed silver nanoparticles. CD-CA/PDA-0.5Ag displayed a high adsorption capacity of methylene blue (535.93 mg/g), which is mainly attributed to electrostatic interactions, host-guest inclusions and π-π bond stacking effects. Furthermore, both diffusion inhibition zone tests and colony formation unit tests were investigated, which showed excellent antimicrobial capability on Escherichia coli (E. coli) and Staphylococcus aureus (S. auerus). Overall, CD-CA/PDA-Ag proved to have an excellent adsorption capacity and antibacterial performance, which provides a great potential in water purification.

The inactivation of an isolated sulfonamide antibiotic resistant bacteria (ARB) HLS-6 and reduction of intracellular sul1 and intI1 in its genome by UVC irradiation, PMS oxidation and UVC-activated peroxymonosulfate (UVC/PMS) treatments were investigated in this study. The UVC/PMS treatment was superior to the other two methods in the inactivation of ARB and reduction of qPCR-sul1 and qPCR-intI1. The HLS-6 ARB (108 CFU/mL) could be effectively inactivated 5.3 log by UVC (100 μW/cm2)/PMS (1 mg/L), and the reduction rates of qPCR-sul1 and qPCR-intI1 by UVC (100 μW/cm2)/PMS (20 mg/L), reached up to 2.9 log and 3.4 log, respectively within 30 min. qPCR-intI1 reacted faster than qPCR-sul1 in all methods. Sulfate radical was responsible for the reduction of target genes, while hydroxyl radical had negligible effect on that. The dosage of PMS positively affected the reduction of both genes during UVC/PMS, while the initial concentration of ARB could negatively influence the reduction of target genes. The pH 5 of reaction solution was most beneficial to the reduction of ARGs. The reduction rates at pH 5 reached up to 3.1 log (sul1) and 3.3 log (intI1). The reduction of target genes was slightly facilitated in the initial 5 min and suppressed after 5 min with the co-existence of sulfamethoxazole. This study will provide a potential alternative method for controlling the antibiotic resistance in aquatic environment.

Antibiotic resistance genes (ARGs) and their host antibiotic-resistant bacteria (ARB) are widely detected in the environment and pose a threat to human health. Traditional disinfection in water treatment plants cannot effectively remove ARGs and ARB. This study explored the potential of a heterogeneous photo-Fenton-like process utilizing a hierarchical macro-mesoporous Co

Various pollutants are released during pharmaceutical production processes, which is of great concern. Most studies have focused on the end treatment results of mixed pharmaceutical wastewater, and further research on wastewater from production processes is required. This study investigated the wastewater quality indicators, residual antibiotics, and biological toxicity of the wastewater during the production process in a large pharmaceutical producing factory in North China. The wastewater contained numerous organic pollutants, with the chemical oxygen demand (COD) values ranging from 2.0 × 103 to 2.6 × 105 mg L−1 and the total nitrogen (TN) values ranging from 1.3 × 103 to 2.0 × 104 mg L−1. High concentrations of cephalexin and cefradine remained in the wastewater of the production workshop, with the highest concentration of cefradine reaching 1328 mg L−1. The wastewater from the oxidation and solvent recovery workshops was more toxic to Vibrio fischeri and Daphnia magna than that of other workshops. Moreover, the biological acute toxicity of wastewater was significantly correlated (p

The application of animal manure is highly recommended in agricultural production. However, the effect of different kinds of manures on bacterial community in farmland still remains unclear. In this study, a short-term field experiment was conducted to investigate the rapid effects of pig manure (PM), chicken manure (CM) and organic fertilizer (OF, composted by pig manure) application on soil physicochemical properties and soil bacterial community. The results showed that the application of CM and OF significantly increased soil bacterial richness (p , the organic matter synthetic bacteria, and Nitrospirae, the nitrifying bacteria, by 17.18% and 40.00%, respectively. 16S functional prediction analysis results shows that the application of OF increased the relative abundance of genes encoding Ribulose-1,5-bisphosphate carboxylase/oxyg (RuBsiCO), the genes involved in soil Calvin cycling, by 20.51%, and increased the relative abundance of genes encoding nitrous-oxide reductase by 44.86%. In conclusion, Short-term application of OF had greater disturbance to soil bacteria than CM and PM, and it had a significant influence on soil functional bacteria and genes involved in soil carbon and nitrogen cycling.

A halophilic PAHs-degrading strain, Martelella AD-3, was previously isolated from highly saline petroleum-contaminated soil. In this study, label-free proteomics were performed to identify differentially expressed proteins (DEPs) under Group P (phenanthrene +5% salinity) and Group G (glycerol +1% salinity), which would help to reveal the mechanism of phenanthrene degradation and salt tolerance. A total of 307 up-regulated DEPs were found in Group P, including 17 phenanthrene degradation proteins. Among these phenanthrene-degrading proteins, the ferredoxin of aromatic ring-hydroxylating dioxygenase (RHD) was up-regulated by 110-fold and gentisate 1,2-dioxygenases (GDOs) were only expressed in Group P. Besides, we also found nine high salt stress response proteins, including ectoine synthase and transport protein of compatible (osmoprotectant) solutes, were differentially up-regulated. These results indicate that strain AD-3 mainly relied on RHD and dihydrodiol dehydrogenase to degrade phenanthrene, and accumulated compatible solutes for resistance to salt stress. This study provides strong theoretical guidance for understanding the degradation of phenanthrene by strain AD-3 in high salt environments.

To better understand the toxicity of tetrabromobisphenol A (TBBPA), its effects on the model nematode Caenorhabditis elegans were investigated. Following a step and repeated chronic exposure from L4-larvae to day-10 adult, physiology endpoints (growth and locomotion behaviors including head thrashes, body bends and pumping rate), biochemical endpoints (reactive oxygen species, superoxide dismutase activity, catalase activity), and molecular stress-related gene expression were tested at environmentally relevant concentrations of TBBPA (0.01–100 µg/L). The results showed that concentrations of TBBPA greater than 10 µg/L, clearly influenced the physiology behaviors (growth and locomotion endpoints). Under repeated exposure, C. elegans exhibited adaptive responses in head thrashes and pumping rate. Compared to toxicity evaluation following repeated chronic exposure, a significantly greater response was induced at the same concentration following a step chronic exposure. Reactive oxygen species production was significantly enhanced following a step and repeated TBBPA exposure at the concentrations of 1 and 10 µg/L, respectively. qRT-PCR showed that ctl-1, ctl-2, ctl-3 and sod-3 expression significantly increased, which was obviously correlated with physiological and biochemical behaviors under both treatment conditions according to Pearson correlation test analysis. sod-3 and ctl-2 mutations were more sensitive than the wild-type N2 under a step chronic TBBPA exposure at a level of 10 µg/L. Thus, chronic exposure to TBBPA induces an oxidative stress response in C. elegans, with ctl-2 and sod-3 playing a vital role in TBBPA-induced toxicity in nematodes.

This study investigated the reduction of one antibiotic resistance gene (ARG, sul1) and one integron (intI1) within a multiple-antibiotic-resistant bacterium (ARB), Pseudomonas. HLS-6, during UV, chlorination and UV/chlorination. This bacterial strain was easily inactivated by these three methods, but its gene inactivation was not so easy. Two short target gene sequences (sul1-qPCR and intI1-qPCR) were selected for quantitative analysis, and another two longer ones (sul1-PCR and intI1-PCR) were used for qualitative identification. During the initial reaction time ( chlorination>UV. The log reduction of sul1-qPCR and intI1-qPCR in UV/chlorination achieved >3.50 and 4.00 log, respectively. The removal efficiency of sul1-PCR and intI1-PCR was also identified by gel electrophoresis analysis, which further confirmed the advantage of UV/chlorination treatment on DNA damage. Among the radicals produced in UV/chlorination, only the reactive chlorine species (Cl⋅, Cl2⋅− and ClO⋅) can degrade the target genes. Under the condition of low chlorine dosage, sul1-qPCR was easier to be removed than intI1-qPCR by UV/chlorination. The log reduction of both sul1-qPCR and intI1-qPCR decreased with pH increasing during UV/chlorination. In the presence of sulfamethoxazole, UV/chlorination showed more advantages than direct UV and chlorination in the simultaneous removal of antibiotics, ARBs and ARGs.

The solid phase extraction (SPE) method is often used to enrich trace antibiotics in water before analysis by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), but the improvement of extraction efficiency has always been the hot issue in this method, which may be realized by developing new SPE materials and optimizing extraction conditions. Tetracyclines (TCs) are a class of common antibiotics, but appropriate SPE materials specifically used to detect them are lacking. Common SPE materials show low and unstable recoveries during the extraction and detection of TCs. In this study, a novel diol-based porous organic polymer (NTdiol-POP) was used as a new SPE material to detect trace TCs in water. This material has specific adsorptive properties for TCs via hydrogen bonds, electrostatic attractive interactions, and π–π interactions. The results show that the NTdiol-POP cartridges have higher recoveries (83.3–118.1%) for determining TCs than common SPE cartridges. Under optimum SPE conditions using NTdiol-POP, TCs were adsorbed at pH 5.0 and eluted with a solution of formic acid/methanol (7%/93%, v/v). Meanwhile, chromatographic separation conditions and MS/MS parameters in multiple reaction monitoring (MRM) mode were optimized to improve the sensitivity and specificity of the instrumental analysis. The limit of detection varied from 0.078 to 2.18 ng L−1, while the limit of quantification varied from 0.26 to 7.25 ng L−1. An assessment of the matrix effects in drinking water exhibited a slight signal variation for most TCs (−8.4% to 2.5%) except oxytetracycline, for which the detection signals were enhanced by 27.0%. The proposed method was successfully applied to determine the trace TCs in three reservoirs of East China.

Antibiotic resistance genes (ARGs) and their host antibiotic-resistant bacteria (ARB) are widely detected in the environment and pose a threat to human health. Traditional disinfection in water treatment plants cannot effectively remove ARGs and ARB. This study explored the potential of a heterogeneous photo-Fenton-like process utilizing a hierarchical macro-mesoporous Co3O4-SiO2 (MM CS) catalyst for activation of peroxymonosulfate (PMS) to inactivate ARB and degrade the intracellular ARGs. A typical gram-negative antibiotic-resistant bacteria called Pseudomonas sp. HLS-6 was used as a model ARB. A completed inactivation of ARB at ∼107 CFU/mL was achieved in 30 s, and an efficient removal rate of more than 4.0 log for specific ARGs (sul1 and intI1) was achieved within 60 min by the MM CS-based heterogeneous photo-Fenton-like process under visible light and neutral pH conditions. Mechanism investigation revealed that •O2− and 1O2 were the vital reactive species for ARB inactivation and ARG degradation. The formation and transformation of the active species were proposed. Furthermore, the hierarchical macro-mesoporous structure of MM CS provided excellent optical and photoelectrochemical properties that promoted the cycle of Co3+/Co2+ and the effective utilization of PMS. This process was validated to be effective in various water matrices, including deionized water, underground water, source water, and secondary effluent wastewater. Collectively, this work demonstrated that the MM CS-based heterogeneous photo-Fenton-like process is a promising technology for controlling the spread of antibiotic resistance in aquatic environments.

The super-resistant bacteria that produce the New Delhi metallo-β-lactamase 1 (NDM-1) enzyme are becoming a conceivably major worldwide clinical issue with serious consequences. Studying the disinfection and mechanism of super-resistant bacteria and their antibiotic resistance genes (ARGs) is crucial for controlling their spread in the water environment. In this study, the disinfection of the super-resistant bacterium Acinetobacter sp. CS-2 and its transferable ARGs (plasmid-encoded blaNDM-1 and blaOXA-58) by ultraviolet radiation (UV), peroxymonosulfate (PMS), and ultraviolet/peroxymonosulfate (UV/PMS) exposure were investigated. UV/PMS could completely inactivate CS-2 and control the photoreactivation risk, while bacteria that underwent UV and PMS treatment had survival ratios of 0.22% and 0.28%, respectively. The removal efficiencies of blaNDM-1 and blaOXA-58 ranged from 3.64 to 4.05 log, and the advantage of UV/PMS treatment on ARGs damage was further identified by gel electrophoresis analysis. The removal efficiency of blaNDM-1 was lower than that of blaOXA-58, which was attributed to the low number of adjacent 5′-TT-3′ harbored by blaNDM-1. The removal rate constants of the ARGs by UV treatment were significantly correlated with the number of adjacent base pairs (e.g., 5′-TT-3′, 5′-CT-3′, 5′-TC-3′ and 5′-CC-3′) and length, with R-values ranging from 0.9044 to 0.9512. Singlet oxygen (1O2) played a vital role in the reduction of blaNDM-1 and blaOXA-58 in the UV/PMS treatment. UV/PMS showed high removal efficiency under natural pH conditions and in the presence of various aqueous ions (e.g., Cl−, SO42− and HCO3−). Overall, this study provides new understandings and theoretical support for the risk control of super-resistant bacteria and plasmid-encoded ARGs.

Sulfonamides (SAs) and sul antibiotic resistance genes (ARGs) have been extensively detected in drinking water sources and warrant further studies on the removal of them in different drinking water treatment processes (DWTPs). The prevalence of 13 SAs, sul1, sul2 and class I integrase gene intI1 in conventional and advanced processes was investigated using HPLC-MS/MS and real-time quantitative PCR (qPCR), respectively. The most abundant SA was sulfamethoxazole, with the maximum concentration of 67.27 ng/L. High concentration of sulfamethoxazole was also measured in finished water in both conventional (22.05 ng/L) and advanced (11.24 ng/L) processes. Overall, the removal efficiency of advanced process for each SA was higher than that of conventional process, except for sulfameter. The absolute concentrations of sul1, sul2 and intI1 in raw water ranged from 1.8 × 103 to 2.4 × 105 gene abundance/mL. After treatment, the residual sul ARGs and intI1 in finished water still remained at 102 - 104 gene abundance/mL. Conventional treatment units, including flocculation/sedimentation/sand filtration, played a more important role in removing sul1, sul2 and intI1 than oxidation (chlorination or ozonation) and granular activated carbon filtration treatments. Based on this work, more investigations are needed to help improve the removal of both antibiotics and ARGs in DWTPs.

The coexistence of anionic dye, cationic dye and endocrine-disrupting chemicals (EDCs) in dyeing wastewater has highlighted a great necessity to develop new and effective approaches for their simultaneous removal. In this study, a novel amphoteric adsorbent was successfully synthesized using a two-step strategy, starting with the preparation of citric acid (CA) crosslinked β-cyclodextrin (CD) polymer (CD/CA) through esterification reactions, followed by the grafting of 2-dimethylamino ethyl methacrylate monomer (PDMAEMA) through polymerization reaction. Adsorption performance of the synthesized material (CD/CA-g-PDMAEMA) toward EDCs (bisphenol A, BPA), cationic dye (methylene blue, MB) and anionic dye (methyl orange, MO) in the monocomponent and multicomponent systems were evaluated. The adsorbent showed a maximum adsorption capacity (qmax) of 79.0 mg/g for BPA at pH 6.5, 165.8 mg/g for MO at pH 4.0 and 335.5 mg/g for MB at pH 11.0, respectively. By altering the solution pH, zeta-potential of the adsorbent could be changed, endowing the material with selective adsorption properties toward anionic or cationic dyes, while BPA adsorption efficiency was vastly insusceptible to the changes in solution pH from 2.0 to 10.0. These characteristics are beneficial for the application of CD/CA-g-PDMAEMA in real wastewaters treatment. In addition, the pseudo-second-order model fitted well with the experimental data in both monocomponent and multicomponent systems, and the adsorption mechanisms were proposed: BPA could form inclusion complex with β-cyclodextrin cavities, while MB and MO molecules could interact with the carboxyl and tertiary amino groups on CD/CA-g-PDMAEMA through electrostatic attractions.

The discharge of pharmaceutical wastewater introduces numerous pollutants into the environment, and their pollution level reduction has aroused extensive concern. This study investigated the variation in residual antibiotics and ecotoxicity to two nutritional-level model organisms in the pharmaceutical wastewater treatment process (PWTP). The wastewater in the equalization tank contained massive organic matters (2.9-18.7 times higher than the permissible values in GB21903-2008) and antibiotics (310.88 μg/L), posing extremely toxic effects to Vibrio fischeri (V. fischeri) and Daphnia magna (D. magna). The biological anaerobic/aerobic treatment units contributed the most to the reduction of antibiotics and the ecotoxicity to both organisms, with the removal rates of 72% and 90%, respectively. The ecotoxicity of pharmaceutical wastewater was strongly and positively correlated with the residual antibiotics, amoxicillin, cephalexin, ammonia nitrogen, and total phosphorus (P 0.05). However, the detected amounts of amoxicillin and cephalexin were approximately 10

Antibiotic resistance genes (ARGs) are extensively detected in various environmental media, whose risk assessment in the drinking water systems has not been comprehensive. This study established a new risk assessment of ARGs in the drinking water systems, considering the chlorine-resistance ability, transferability, and ARGs harboring potential of pathogens. The risk of ARGs in a typical drinking water reservoir was also evaluated based on the detection of ARGs and antibiotic-resistant bacteria (ARB). Fourteen ARGs were detected with a relative concentration range of 10-4-10-3 (ARGs/16S rRNA gene). Five isolated ARB were identified as human opportunistic pathogens, one of which (Pseudomonas aeruginosa HLS-6, CCTCC AB 2017269) is resistant to hundreds of milligrams per liter levels of antibiotics and low-level chlorine. This result indicated that ARB tolerant to high-levels of antibiotics could be isolated from environments containing trace levels of antibiotics. Moreover, complete genome sequencing confirmed the inclusion of ARGs (sul1, aadA2) on the class I integron in HLS-6, indicating that the risk of ARGs in this drinking water reservoir could be classified as resistance risk ranking in drinking water system 1 (R3DW 1). The risk assessment of ARGs in this study provides a clear understanding of ARG risk in drinking water systems. The results reveal that the ARGs and ARB contamination of drinking water reservoirs pose significant challenges for drinking water treatment efficiency and affect drinking water safety.

The extensive pollution of antibiotics and antibiotic resistance genes (ARGs) in drinking water has aroused worldwide concern. Successive monitoring of these pollutants has noteworthy significance for drinking water safety. Accordingly, this study conducted successive monitoring of antibiotics and ARGs from 2015 to 2017 in a drinking water source in East China. The total antibiotic concentration ranged from 19.68 ng/L to 497.00 ng/L, and decreased slightly from 2015 to 2017. Eighteen out of forty-one ARG subtypes showing resistance to six antibiotic classes and one class I integrase gene intI1, were detected in the drinking water source at concentrations ranging from 6.5 × 104 copies/mL to 1.6 × 106 copies/mL. Importantly, the total ARG concentration increased on an annual basis from 2015 to 2017 with an average annual increment of 0.25 orders of magnitude, which was mainly attributed to the increase in specific ARG subtypes, such as sul1, sul2, sul3, tetA, qnrB, and ermB. Most ARGs was positively correlated with the intI1 genes (r = 0.47–0.55, P

A 2D sandwich-like TiO2-rGO composite was fabricated by the Pickering emulsion approach to improve the photocatalytic efficiency. Through an in situ growth of antase-TiO2 nanoparticles on the interface of O/W type GO Pickering emulsion, TiO2 nanoparticles were closely and densely packed on the surface of well-exfoliated rGO sheets; meanwhile, many mesoporous voids acting as the adsorption chamber and microreactor were produced. Evaluated by methylene blue (MB) degradation, its photocatalytic activity was prominent compared with the common TiO2-based photocatalyst, with the rate constants 5 and 3.1 times higher under visible light and xenon lamp, respectively. When we applied it in the photocatalytic degradation of tetracycline hydrochloride (TCH, such as 10 ppm) under the visible light without adding any oxidants, the total removal efficiency was as high as 94% after 40 min. The mechanism of this good photocatalytic efficiency was illustrated by the scavenger trapping tests, which showed that this unique ...

The soil microbiota conducts important biological ecosystem functions, but the mechanism underlying community-environment interactions for soil microbiota remains unclear. By using two distinct soils for cross inoculation, we successfully simulated the assembly of the bacterial community in sterile soil. Thus, the reasons why inoculum and recipient have dominated community assembly in previous investigations are investigated in this study. We found that inoculated bacteria presided over environmental selection for community assembly due to the varied difference of ecological equivalent bacteria, either divergent or convergent. The significance of neutrality for the ecologically equivalent bacterial species that immigrated into the recipients should be emphasized in exploring the mechanisms of community assembly. Our finding is helpful for understanding the community-environment interaction, a basic question in ecology, and it would shed light on this issue that has perplexed scientists for many years., Exploring the assembly mechanism of microbiota is critical for understanding soil ecosystem functions. However, the relative importance of different biotic and abiotic factors in determining the bacterial community has not been properly clarified. In this study, the effects of inocula and recipients on the assembly of the soil community were investigated to evaluate their importance by inoculation experiments with sterile soil. Two distinct soils, conventional nitrogen-fertilized soil and aromatic-compound-contaminated soil, were sterilized, cross inoculated, and incubated for 2 months under different inoculation doses and oxygen conditions. The results showed that the greatest variation in community structure emerged in the samples inoculated with distinct inocula rather than in the samples of different soil recipients. The phylogenies in the two inocula were diverse and dissimilar, although there were many ecologically equivalent bacteria. When the inocula with dissimilar ecologically equivalent species were used, the assembled communities were primarily determined by the inocula as indicated by the beta diversity and variation partitioning analyses. In contrast, environmental selection dominated the process when ecologically equivalent species in the inocula were similar, as when only one type of inoculum was used, where the soil habitat selected the most adaptive bacteria from the defined inoculum pool. These results indicate that inoculated bacteria are dominant over environmental selection if they are sufficiently dissimilar, although the effect of environmental selection is more obvious when similar bacteria are inoculated in the soil for community assembly. Our findings suggest that the immigration of exotic bacteria could be a primary factor impacting community assembly. IMPORTANCE The soil microbiota conducts important biological ecosystem functions, but the mechanism underlying community-environment interactions for soil microbiota remains unclear. By using two distinct soils for cross inoculation, we successfully simulated the assembly of the bacterial community in sterile soil. Thus, the reasons why inoculum and recipient have dominated community assembly in previous investigations are investigated in this study. We found that inoculated bacteria presided over environmental selection for community assembly due to the varied difference of ecological equivalent bacteria, either divergent or convergent. The significance of neutrality for the ecologically equivalent bacterial species that immigrated into the recipients should be emphasized in exploring the mechanisms of community assembly. Our finding is helpful for understanding the community-environment interaction, a basic question in ecology, and it would shed light on this issue that has perplexed scientists for many years.

Tetrabromobisphenol A (TBBPA), one of the most common brominated flame retardants, has been associated with immunotoxicity, neurotoxicity, and reproductive toxicity. However, little attention has been focused on understanding the trans-generational effects of TBBPA. The present study used the Caenorhabditis elegans (C. elegans) animal model to evaluate the trans-generational effects of neurotoxicity induced by environmentally relevant concentrations of TBBPA (0, 0.1, 1, 10, 100, and 1000 µg/L). Multiple indicators including physiological effects (body length, brood size, head thrashes, body bends, and crawling trajectory), degree of neuronal damage (dopamine, GABAergic, and glutamatergic neurons), oxidative stress-related biochemical indicators (superoxide dismutase [SOD] activity, catalase [CAT] enzyme, malondialdehyde [MDA] production, and reactive oxygen species [ROS] accumulation), and stress-related gene expressions have been evaluated in the exposed parental C. elegans generation (G1) and their progeny (G2) under TBBPA-free conditions. The results showed that TBBPA exposure induced adverse effects on physiological endpoints, among which body bends and head thrashes were the most sensitive ones, detected above 1 µg/L in G1 and 100 µg/L in G2 nematodes, respectively. After contaminant exposure, the three neurons revealed damage related to neurobehavioral endpoints, with no hereditary effects in the progeny. The oxidative stress-related biochemical endpoints demonstrated that when the exposure concentrations were above 1 µg/L in maternal worms, impairment can be detected in both generations, but the progeny recovered at low toxicity concentration (1–100 µg/L). The integrated target gene expression profiles were clearly altered in G1 and G2 worms at concentrations between 1 and 1000 µg/L, and a more significant difference existed in two generations of nematodes at low levels (1–10 µg/L) of TBBPA. Studing trans-generational neurotoxicity and the underlying mechanism can generate a precise evaluation of the environmental risk of TBBPA.

Excessive sulfonamides accumulated in soil and groundwater seriously menace the ecological environment and human health. The performance of a Fenton-like system applying Fe

The widespread use of tetrabromobisphenol A (TBBPA) in industries has resulted in its frequent detection in environmental matrices, and the mechanisms of its associated hazards need further investigation. In this study, the nematode Caenorhabditis elegans (C. elegans) was exposed to environmentally relevant concentrations of TBBPA (0, 0.1, 1, 10, 100, 200 μg/L) to determine its effects. At TBBPA concentrations above 1 μg/L, the number of head thrashes, as the most sensitive physiological indicator, decreased significantly. Using the Illumina HiSeq™ 2000 sequencer, differentially expressed genes (DEGs) were determined, and 52 were down regulated and 105 were up regulated in the 200 μg/L TBBPA treatment group versus the control group. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database analysis demonstrated that dorso-ventral axis formation is related to neurotoxicity; metabolism of xenobiotics by Cytochrome P450 (CYP450) and glutathione-S-transferase (GST) was found to be the vital metabolic mechanisms and were confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). GST was ascribed to the augmentation because mutations in cyp-13A7 were constrained under TBBPA exposure. Additionally, oxidative stress indicators accumulated in a dose-dependent relationship. These results will help understand the molecular basis for TBBPA-induced toxicity in C. elegans and open novel avenues for facilitating the exploration of more efficient strategies against TBBPA toxicity.

Trace levels of residual antibiotics in drinking water may threaten public health and become a serious problem in modern society. In this work, we investigated the degradation of twelve sulfonamides (SAs) at environmentally relevant trace level concentrations by three different methods: ultraviolet (UV) photolysis, peroxymonosulfate (PMS) oxidation, and UV-activated PMS (UV/PMS). Sulfaguanidine, sulfadiazine, sulfamerazine, sulfamethazine, sulfathiazole, sulfamethoxydiazine, and sulfadimethoxine were be effectively removed by direct UV photolysis and PMS oxidation. However, sulfanilamide, sulfamethizole, sulfamethoxazole, sulfisoxazole, and sulfachloropyridazine were not completely degraded, despite prolonging the UV irradiation time to 30min or increasing the PMS concentration to 5.0mg·L-1. UV/PMS provided more thorough elimination of SAs, as demonstrated by the complete removal of 200ng·L-1 of all SAs within 5min at an initial PMS concentration of 1.0mg·L-1. UV/PMS promoted SA decomposition more efficiently than UV photolysis or PMS oxidation alone. Bicarbonate concentration and pH had a negligible effect on SA degradation by UV/PMS. However, humic acid retarded the process. Removal of 200ng·L-1 of each SA from a sample of sand-filtered effluent from a drinking water treatment plant (DWTPs) was quickly and completely achieved by UV/PMS. Meanwhile, about 41% of the total organic carbon (TOC) was eliminated. Scavenging experiments showed that sulfate radical (SO4-) was the predominant species involved in the degradation. It is concluded that UV/PMS is a rapid and efficient method for removing trace-level SAs from drinking water.

To investigate biological effects of bisphenol A (BPA) over the long term, the model animal Caenorhabditis elegans was used to conduct the chronic exposure. C. elegans were exposed to BPA (0.0001-10 μM) from L4 larvae to day-10 adult in the present chronic toxicity assay system. Multiple endpoints at the physiological (growth, locomotion behaviors and lifespan), biochemical (lipofuscin accumulation), molecular (stress-related genes expressions), and population (population size) levels were examined. At the physiological level, BPA exposure induced significant negative effects on the indicators. Among the endpoints, head thrash was most sensitive and the detection limit was 0.001 μM. At the biochemical level, BPA exposure induced no significant effects on lipofuscin accumulation. At the molecular level, BPA induced strong stress responses in vivo. At the population level, the population size was significantly decreased in the treatment groups from 0.1 to 10 μM. Compared to the previous short-term toxicity evaluation, long-term exposure to BPA induced a more obvious response at the same concentration, and the phenomenon might be due to cumulative toxic effects. By the Pearson correlation analyses, cep-1 was speculated to act as an important role in BPA-induced chronic toxicity on C. elegans.

The efficient degradation of fluoroquinolone antibiotics and the reduction of their antimicrobial activity were achieved in different water matrices through the photocatalysis of inverse opal potassium-doped carbon nitride (IO K-CN). The IO K-CN photocatalyst with optimum doping ratio of potassium performed much better than bulk carbon nitride and pure inverse opal carbon nitride for removing fluoroquinolone antibiotics, such as levofloxacin (LVX) and norfloxacin (NOR). The remarkably narrowed band gap resulting from potassium doping and the unique properties of the inverse opal construction jointly contributed to enhancing the activity of the photocatalyst. A possible mechanism and degradation pathway for LVX was proposed on the basis of a series of characterizations including electron spin resonance (ESR) experiments, and liquid chromatography-mass spectrometry (LC-MS) analysis. Meanwhile, the byproducts during the LVX photocatalytic degradation were shown to have much lower sterilization effect, implying that the toxicity and the potential risk of LVX were excellently reduced. The potential application for the treatment of antibiotic-containing wastewater was indicated by the excellent treatment efficiency and favorable durability of this photocatalyst.

Antibiotic resistance is extensively detected in drinking water sources, threatening its safety and human health, which deserves further attention to the removal of antibiotic resistance genes (ARGs) in the drinking water system. In this study, the occurrence and reduction of integrase gene intI1 and forty-one ARG subtypes, which confers resistance to six antibiotic classes (β-lactam, aminoglycoside, macrolide, tetracycline, sulfonamide, and quinolone), were investigated in a drinking water treatment plant (DWTP). Seventeen ARG subtypes with absolute concentrations ranging from 1.4 × 100 to 7.3 × 105 and 3.9 × 104 genes/mL (intI1) were detected in the raw water; and sul1 and sul2 were the two dominant ARG subtypes. Overall, the whole DWTPs achieved 0.03–2.4 log reduction of ARGs compared with those presented in raw water. The reduction efficiencies of sul1, strA, and intI1 were the highest (1.0–2.4 log) in both conventional and advanced processes. However, the levels of sul1, sul2, and ermC still remained high (1.3 × 100–1.9 × 104 genes/mL) in finished water. The treatment units, including pre-flocculation/sedimentation/sand filtration, and ozonation units, were beneficial for the reduction of ARGs, which was mostly ascribed to the decline in biomass and the strong oxidizing properties of ozone. However, the reduction effect was subsequently counteracted by the granular activated carbon and chlorination units. This study provides basic data for ARG pollution in the drinking water system, and suggests that ARGs persist in drinking water, even after conventional chlorination or advanced treatment processes, highlighting the need for new and efficient water purification technologies.

Pre-chlorination and UV disinfection are two common processes in drinking water treatment plants. Sulfamethoxazole (SMX), an antibiotic widely detected in source water, was selected as a precursor to study the conversion of chlorine/nitrogen species and DBP formation in pre-chlorination/post-UV process. The combined chlorine (mainly organic chloramines) produced in pre-chlorination of SMX can self-degrade and release free chlorine back again as pre-chlorination time goes on. With free chlorine dose increasing, the self-degradation rate of combined chlorine increased obviously. But the combined chlorine stopped self-degrading and remained stable around 1 mg-Cl2/L after adding 0.30 mM chlorine for 30 min. Post-UV treatment after pre-chlorination can enhance the degradation and achieve a complete removal of combined chlorine (including organic chloramines). Deamination occurred during pre-chlorination/post-UV process and deamination amount (-NH2) per SMX concentration was 0.19 M/M. Radicals in this process had no obvious influence on chlorine/nitrogen species conversion. Direct chlorination of SMX had the lowest DBP formation potentials while the application of pre-chlorination and UV enhanced them. Compared with UV treatment only, dichloroacetonitrile formation potential of SMX reduced by 1.58 × 10−3 mol/mol-SMX (17.37 μg/l) after pre-chlorination/post-UV treatment. During pre-chlorination/post-UV/final-chlorination treatment of SMX, Br− and natural organic matter can enhance DBP formation and toxicity-weighted values. Acid conditions showed a very high DBP risk, while alkaline conditions could cut this risk obviously, especially for the toxicity-weighted values of these DBPs.

An efficient novel amphiphilic material composed of core-double shells nanocomposite (CDSN) with nanoscale zero-valent iron (NZVI) as the core and PS100-b-PAA16 as inner shell and chitosan as outmost shell has been synthesized successfully. Its application to remove the trichloroethylene (TCE) in stimulated TCE solution with 7.3 ± 0.3 mg/L dissolved oxygen was investigated. The results showed that CDSN after exposure to air for a month could still remove 92.6% of TCE as compared to 61.5% removal rate of NZVI in 360 min (the gram ratio of material: TCE equals to 10:1), exhibiting the great oxidation resistance performance. Specifically, dynamic research of the total removal divided into adsorption by shell layer and degradation by reducibility of NZVI at a predetermined interval was engaged to understand the complete mass transfer process of TCE. The results revealed that CDSN adsorbed 1.5 to 2 folds time TCE as compared to NZVI in the same initial pH = 8.5 aqueous solution. Importantly, CDSN could sustain fixed reactivity to remove about 94.8% of TCE from the start to end. NZVI exhibited greater removal capacity in first 180 min, but later it lost the reducibility and finial removal rate was 89%. The selective adsorption to protonated CDSN was strengthened to increase the removal of TCE at pH 3.5 while NZVI had a worse removal in pH 3.5 performance than pH 8.5.

Adsorption is recognized as one of the most efficient approaches for antibiotics removal from water. Inspired by the enzyme-substrate interaction model, we proposed induced-fit adsorption (IFA) model, and rationally designed and fabricated diol-based porous organic polymers (POPs) as adsorbents for tetracycline (TC) removal. For 2,3-naphthalenediol-based POP (NTdiol-POP), the preferable geometry of diol-groups contributed to the high binding energy with TC species and flexible methylene linkages between neighboring rigid naphthalene rings gave rise to precisely matching between TC species and adsorbents, that is, the induced-fit conformation change. As a result, NTdiol-POP exhibited a high saturated adsorption capacity of 155.8 mg g−1. More importantly, NTdiol-POP exhibited excellent TC removal efficiencies in both concentrated solution (96% for 4 p.p.m) and trace level solution (97% for 250 p.p.b).

The presence of antibiotics in drinking water sources is worthy of concern regarding their potentially harmful effects on drinking water quality. In this study, a sensitive and reliable method was developed for the detection of 14 antibiotics in drinking water sources based on solid phase extraction (SPE) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The primary parameters for the SPE procedure, including different SPE cartridges, pH value of the sample, extraction volume and washing conditions, were optimized to extract the analytes efficiently in a single step with improved recoveries. Chromatographic separation conditions and MS/MS parameters in multiple reaction monitoring (MRM) mode were optimized to improve the sensitivity and specificity of the method. The optimized method provided acceptable recoveries ranging from 60.5% to 103.3%. The validation study indicated that the method detection limits varied from 0.001 to 2.160 ng L−1 and the method quantification limits varied from 0.003 to 6.740 ng L−1. The precision of the method, expressed as relative standard deviation (RSD), ranged from 0.1% to 2.6% and from 0.3% to 3.8% for inter- and intra-day analyses, respectively. Assessment of matrix effects exhibited partial signal suppression from 1.2% to 28.7% for most analytes, but it indicated signal enhancement for tetracycline (15.2%) and oxytracycline (12.6%). The method was successfully applied to the determination of trace levels of antibiotics in drinking water sources in East China. Up to 13 antibiotics were detected at concentrations ranging from 0.16 to 147.05 ng L−1, and the primary antibiotic residues belonged to the groups of fluoroquinolones and tetracyclines.