[Contamination Characteristics and Ecological Risk of Antibiotics in Contaminated Sites of Typical Pharmaceutical Factories in China].

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.

Biotransformation of sulfamonomethoxine in a granular sludge system: Pathways and mechanisms.

The biotransformation of sulfamonomethoxine (SMM) was studied in an aerobic granular sludge (AGS) system to understand the role of sorption by microbial cells and extracellular polymeric substances (EPS) and the role of functional microbe/enzyme biodegradation. Biodegradation played a more important role than adsorption, while microbial cells covered with tightly bound EPS (TB-EPS) showed higher adsorption capacity than microbial cells themselves or microbial cells covered with both loosely bound EPS (LB-EPS) and TB-EPS. The binding tests between EPS and SMM and the spectroscopic analyses (3D-EEM, UV-Vis, and FTIR) were performed to obtain more information about the adsorption process. The data showed that SMM could interact with EPS by combining with aromatic protein compounds, fulvic acid-like substances, protein amide II, and nucleic acids. Batch tests with various substances showed that SMM removal rates were in an order of NH2OH (60.43 ± 2.21 µg/g SS) > NH4Cl (52.96 ± 0.30 µg/g SS) > NaNO3 (31.88 ± 1.20 µg/g SS) > NaNO2 (21.80 ± 0.42 µg/g SS). Hydroxylamine and hydroxylamine oxidoreductase (HAO) favored SMM biotransformation and the hydroxylamine-mediated biotransformation of SMM was more effective than others. In addition, both ammonia monooxygenase (AMO) and CYP450 were able to co-metabolize SMM. Analysis of UPLC-QTOF-MS indicated the biotransformation mechanisms, revealing that acetylation of arylamine, glucuronidation of sulfonamide, deamination, SO2 extrusion, and δ cleavage were the five major transformation pathways. The detection of TP202 in the hydroxylamine-fed Group C indicated a new biotransformation pathway through HAO. This study contributes to a better understanding of the biotransformation of SMM.

Responses of aerobic granular sludge to fluoroquinolones: Microbial community variations, and antibiotic resistance genes.

In this study, aerobic granular sludge (AGS) was operated under high levels of ammonium for removing three fluoroquinolones (FQs), i.e., ciprofloxacin (CFX), ofloxacin (OFX), and norfloxacin (NFX) at 3, 300, and 900 µg/L, respectively. Two key objectives were to investigate the differential distribution of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in sludge fractions and to evaluate correlations between ARGs and MGEs to nitrifying and denitrifying bacteria. AGS showed excellent stability under the exposure of FQs, with nitrite-oxidizing bacteria (NOB) more sensitive to FQs than ammonium-oxidizing bacteria (AOB). Specific oxygen utilization rates (SOUR) showed a reduction of 26.9% for NOB but only 4.0% of the reduced activity of AOB by 3 µg/L FQs. AGS performed better removal efficiencies for CFX and NFX than OFX, and the efficiencies increased with their elevated concentrations, except at 900 µg/L FQs. The elevated FQ concentrations led to a significant enrichment of intI1 and genus Thauera, while qnrD and qnrS showed no accumulation. Compared to nitrifiers, FQs relevant ARGs and the intI1 gene preferred to exist in denitrifiers, and the abundance of denitrifiers behaved a decreasing trend with the sludge size. Two quinoline-degrading bacteria were found in the AGS system, i.e., Alicycliphilus and Brevundimonas, possibly carrying qnrS and qnrD, respectively. Their relative abundance increased with the sludge size, which was 2.18% in sludge <0.5 mm and increased to 3.70% in sludge >2.0 mm, suggesting that the AGS may be a good choice in treating FQs-containing wastewater.

Untreated swine wastes changed antibiotic resistance and microbial community in the soils and impacted abundances of antibiotic resistance genes in the vegetables.

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.

[Contamination Characteristics and Ecological Risk Assessment of Androgens, Glucocorticoids, and Progesterone in the Liusha Bay, South China Sea].

Steroid hormones have been continuously detected and well studied in freshwater bodies in recent years, although information regarding their contamination characteristics in seawater is rare. In this paper, samples were collected in Liusha Bay, South China Sea, and the contamination characteristics, as well as the spatial distribution of 33 steroid hormones, were studied by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that 7 steroid hormones occurred with concentrations ranging from 0.003 (medroxyprogesterone, MP) to 9.023 ng·L-1(dehydroprogesterone, DGT), and from 0.017 (androsta-1,4-diene-3,17-dione, ADD) to 9.281 ng·g-1 (4-androstene-3,17-dione, AED) in seawater and sediment samples, respectively. The concentrations of detected steroid hormones were higher during wet weather than during the dry weather, and higher in the aquaculture area compared to that in the non-aquaculture area. There were no significant differences in the spatial and temporal distribution of steroid hormones in sediment. Wastewater discharge and additives in aquaculture feeds were the main routes of steroid hormones entering the marine environment. The results of the ecological risk assessment indicated that the AED posed low risk to the marine environment, whereas other steroid hormones posed no risk. Correlation analysis indicated that the concentration distribution of steroid hormones was related to salinity, water temperature, particulate matter (SS), and chemical oxygen demand (COD) in the marine environment. The results of this study contribute to the understanding of the contamination characteristics of steroid hormones in the Liusha Bay area and provide a scientific basis for ecological risk assessment and control.

Characterization of the interactions between tetracycline antibiotics and microbial extracellular polymeric substances with spectroscopic approaches.

The antibiotics have attracted global attentions for their impact on aquatic ecosystem. The knowledge about the fate of antibiotics encountering extracellular polymeric substances (EPS) is, however, limited. In this study, we investigated the interacting mechanisms of tetracycline (TC) to EPS extracted from aerobic activated sludge. The contributions of the main components of EPS, extracellular proteins, and polysaccharides were evaluated using bovine serum albumin and alginate sodium, respectively. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and nuclear magnetic resonance indicated that hydroxyl, carboxyl, and amino groups were the domain chemical groups involved in the interaction between TC and EPS, and the binding of TC onto EPS changed the structure of these chemical groups, thus causing shifts in their UV-visible absorption spectra. In addition, we found that extracellular proteins, rather than polysaccharides, were the major active contents involved in the interaction. Three-dimensional excitation-emission matrix fluorescence spectroscopy showed that the fluorophores in EPS were clearly quenched by TC and the static quenching process was observed, implying the complex formation of TC and EPS. Furthermore, thermodynamic analysis indicated that the binding of TC with EPS is spontaneous and dominated by electrostatic forces.

Fluoride adsorption on carboxylated aerobic granules containing Ce(III).

Aerobic granules (AG) were carboxylated and Ce(III) was incorporated to obtain modified granuels (Ce(III)-MAG) for removal of fluoride from aqueous solutions. The Ce(III)-MAG was characterized by SEM, FTIR, XRD and pH(pzc), and the introduction of carboxyl groups and Ce(III) was confirmed. The adsorption capacity of Ce(III)-MAG for fluoride was 45.80 mg/g at neutral pH, an increase of 359% compared to the capacity of pristine AG. Adsorption was highest at pH range of 3.0-5.0. A positive effect on fluoride removal in the order of K(+) ≈ Mg(2+) > Ca(2+) > Na(+) and a negative effect in the order of NO(3)(-) > Cl(-) > SO(4)(2-) > HCO(3)(-) > PO(4)(3-) was observed. Fluoride adsorption followed the Redlich-Peterson model and the pseudo-first order model with correlation factors of 0.999 and 0.950, respectively. Ce(III)-MAG held up to 790 bed volumes and the effluent fluoride concentration remained below 1.0mg/L (influent fluoride 10mg/L).

Effects of step-feed on granulation processes and nitrogen removal performances of partial nitrifying granules.

Two anoxic/oxic sequencing batch reactors (A/O SBRs) were operated to investigate the effects of step-feed on granulation processes and performances of partial nitrifying granules (PNG). R1 was operated in a traditional single-feed mode, while a two-step-feed strategy was used in R2. Results showed that R1 had a faster granulation process and better performance in maintaining partial nitrification compared with R2, indicating that the step-feed mode had a negative effect of on formation of PNG. However, after full granulation, PNG in both reactors had similar properties in terms of suspended solids (MLSS), sludge volume index (SVI) and granule size. Moreover, mature granules in R2 had a higher nitrite accumulation rate than that in R1. Step-feed strategy was also observed to enhance denitrification and TN removal, as well as ammonia oxidation. It can be concluded that step-feed was unfavorable for cultivating PNG, but it significantly improved the nitrogen removal performance of PNG.

Enhanced aerobic nitrifying granulation by static magnetic field.

One of the main challenging issues for aerobic nitrifying granules in treating high strength ammonia wastewater is the long granulation time required for activated sludge to transform into aerobic granules. The present study provides a novel strategy for enhancing aerobic nitrifying granulation by applying an intensity of 48.0mT static magnetic field. The element analysis showed that the applied magnetic field could promote the accumulation of iron compounds in the sludge. And then the aggregation of iron decreased the full granulation time from 41 to 25days by enhancing the setting properties of granules and stimulating the secretion of extracellular polymeric substances (EPS). Long-term, cycle experiments and fluorescence in-situ hybridization (FISH) analysis proved that an intensity of 48.0mT magnetic field could enhance the activities and growth of nitrite-oxidizing bacteria (NOB). These findings suggest that magnetic field is helpful and reliable for accelerating the aerobic nitrifying granulation.

Sorption and biodegradation of tetracycline by nitrifying granules and the toxicity of tetracycline on granules.

This paper examines the simultaneous sorption and biodegradation performance of tetracycline (TC) by the nitrifying granular sludge as well as the short-term exposure toxicity of TC. The removal of TC was characterized by a quick sorption and a slow process of biodegradation. The adsorption process fits pseudo-second-order kinetic model, with a complex mechanism of surface adsorption and intra-particle diffusion. Both temperature and mixed liquor suspended solid (MLSS) influenced TC sorption to the granules. TC biodegradation was enhanced with the increase of COD and NH(4)(+)-N concentrations, with except of the NH(4)(+)-N concentrations higher than 150 mg/L. With the ATU addition, TC degradation was weakened remarkably, indicating a synergistic effect of multiple microbes. Results of the short-term exposure (12h) effects showed that the respirometric activities of the microbes decreased greatly. The addition of TC also decreased the rate of NH(4)(+)-N utilization considerably, with the half saturation constant (K(s)) increasing from 297.7 to 347.2 mg/L.

Aerobic granulation for nitrogen removal via nitrite in a sequencing batch reactor and the emission of nitrous oxide.

In this study, the granulation of nitrifying-denitrifying via nitrite process in a sequencing batch reactor (SBR) as well as N(2)O emission patterns was investigated. After 60 days of operation, 0.8 mm granules were obtained, and partial nitrification was achieved after NH(4)(+)-N was raised to 350 mg/L. Fluorescence In-Situ Hybridization (FISH) analysis indicated that a fairly large proportion of ammonia-oxidizing bacteria (AOB) was close to the surface but nitrite-oxidizing bacteria (NOB) were rarely found. Batch experiments showed that 64.0% of NH(4)(+)-N in influent was transformed into NO(2)(-)-N, which showed the granules had excellent partial nitrification ability. Inhibition of free ammonia (FA) and limited DO diffusion within granules may contribute to the development and stabilization of partial nitrification. This process did not simultaneously lead to increased N(2)O production. N(2)O emissions at the anoxic and aerobic phases were 0.06 and 13.13 mg N(2)O/cycle, respectively.

[Degradation of phthalate esters in soil and the effects on soil enzyme activities].

Phthalate esters (PAEs) are a kind of widespread toxic organic compounds in the environment. We discussed the different degradation rate of four kinds of PAEs in the soil and its impact on different soil enzyme activities. We used GC-MS methods to determine the concentration of PAEs in soil. The results showed that soil microorganisms play a major role in the degradation of PAEs. The biodegradation diagram of PAEs was accord with first-order kinetics equation. And the shorter carbon chain, the better degradation efficiency. With the high concentration of PAE30, DnOP, which has long carbon chain, the degradation efficiency is lower than that of PAE1 and PAE10, only 73% was degraded after 40 days. We use standard methods to determine the matrix enzyme activities, after adding the PAEs into soil, beta-glucosidase, phosphatase, urease, protease activity have changed. Phosphatase activity decreased at first and then increased, beta-glucosidase activity decreased slowly, protease activity increased at first and then decreased, the activity of urease increased gradually. After 20 days, except for beta-glucosidase activity continued decreasing, the activities of others enzyme recovered gradually, and higher than the control group.

[Impact of phthalic acid easters on diversity of microbial community in soil].

Phthalic acid easters (PAEs) are one of the most extensive organic and poisonous pollutants. BIOLOG and ARDRA method were used to analyze the impact of PAEs on microbial diversity in soil. BIOLOG analysis shows that the increase of average well color development (AWCD) is different in soils dealt with different concentrations of PAEs. With a higher PAEs concentration, the AWCD increases more slowly and the metabolic activity decreases more quickly. Physiological metabolism activity and carbon metabolic group show obvious difference in different samples. Although metabolic groups of carbohydrates and carboxylic acids were the dominant groups in control sample and low concentration sample, the dominant group is main polyamines in middle and high concentration samples. Principal component analysis (PCA) shows the differences of carbon metabolism. Four samples could be separated by PC1. Substrates of high positive correlation coefficients with PC1 were L-asparagine, 4-hydroxy benzoic acid and D-malic acid, but D-galacturonic acid, i-erythritol, gamma-hydroxybutyric acid and glucose-1-phosphate showed high negative correlation. ARDRA analysis showed that the diversity index decreased, with the increased concentration of PAEs. In a short time, PAEs could increase the diversity of microbial genotype in soil.