城市河道再生水特征水质因子空间变异机制分析

受城市污水处理厂处理工艺的限制和水源来源复杂等因素限制,再生水中富含的无机氮和痕量持久性有机物在河湖补给过程中通过侧向渗漏或生物累积的方式造成潜在人体健康风险.探究再生水补给河道不同类型再生水特征水质因子空间变异规律及其成因对于河湖管理具有重要意义.以北运河京津冀段为研究区域,借助于聚类、判别、主成分和方差分解等方法探...     

城市污泥中温厌氧消化过程中厌氧耐药菌的分布与去除研究

城市污泥中含有大量的耐药菌,具有向环境传播耐药菌与抗性基因的潜在危险,但目前缺乏对城市污泥厌氧消化过程中耐药菌的研究.为此对某城市污水处理厂卵形消化池污泥进行了为期1 a的调查研究,考察了中温厌氧消化过程中四环素类与β-内酰胺类抗生素厌氧耐药菌的污染特征与去除效果,并分析了耐药菌的季节性变化规律.结果表明,厌氧进泥中四环素类耐药菌浓度与耐药率均低于β-内酰胺类.中温厌氧消化过程可以去除1.48~1.64 log单位的耐药菌(P<0.05),但经过厌氧消化后氨苄西林与头孢噻吩耐药率有显著增长(分别增加了12.0%与14.3%,P<0.05).厌氧进泥中耐药菌分布有明显的季节特征,除金霉素耐药菌外,其它耐药菌的浓度均为寒冷季显著高于温暖季(P<0.05).     

养猪废水中抗生素和铜对潜流人工湿地土壤呼吸和芦苇光合作用的影响

为了探究养猪废水中抗生素和重金属对潜流人工湿地土壤微生物和植物生长的影响,构建了水平潜流人工湿地和垂直潜流人工湿地,用“根袋”法区分芦苇根际和非根际土壤。每种潜流人工湿地根据进水差异设置4个处理组：进水为模拟养猪废水(CK组)、模拟养猪废水中添加抗生素(抗生素组)、模拟养猪废水中添加铜(Cu组)、模拟养猪废水中同时添加抗生素和Cu(抗生素+Cu组),对2种潜流人工湿地土壤呼吸和芦苇光合作用指标进行为期1年的监测。结果表明：养猪废水中添加18.3~39.1 µg·L⁻¹抗生素或0.8~1.2 mg·L⁻¹铜均可抑制潜流人工湿地的芦苇根际、非根际土壤呼吸和芦苇的光合作用。与CK组相比,在抗生素和Cu复合胁迫下,水平和垂直潜流人工湿地芦苇根际土壤呼吸分别下降了20.4%~66.3%和20.8%~77.5%,非根际土壤呼吸分别下降了30.4%~71.0%、23.2%~60.7%,垂直潜流人工湿地的芦苇根际、非根际土壤呼吸在春、夏、秋季均显著高于水平潜流人工湿地。在抗生素和Cu复合胁迫下,水平潜流人工湿地和垂直潜流人工湿地芦苇的株高在运行后期与CK组相比均显著降低。与CK组相比,水平潜流人工湿地和垂直潜流人工湿地芦苇净光合速率分别下降了11.0%~73.8%和15.2%~45.3%,气孔导度和蒸腾速率也受到了抑制,胞间CO₂浓度则呈增加趋势。垂直潜流人工湿地比水平潜流人工湿地对养猪废水具有更好的深度处理能力。     

畜禽沼液中抗生素和激素的微波处理

通过间歇处理和连续处理实验,探讨微波技术对沼液中四环素类抗生素和激素喹乙醇去除的效果。结果表明,沼液在微波间歇处理中,最优反应时间为40min。此条件下沼液中喹乙醇、土霉素、四环素和金霉素的去除率分别达到26％、49％、48％和70％;微波可显著提高可生化性,BOD5／COD值达到0．37。微波一好氧处理系统中COD与氨氮的去除率分别达到91％和93％,明显优于单独好氧处理。沼液微波连续处理中,最优HRT为90min,此时喹乙醇、土霉素、四环素和金霉素的去除率分别达到24％、45％、50％和74％;BOD5／COD值达到0．34。微波．好氧处理系统中COD与氨氮的去除率均为90％,优于单独好氧处理效果。     

Photodegradation of sulfonamide antibiotics in simulated and natural sunlight: Implications for their environmental fate

The photochemical fate of seven sulfonamides was investigated in matrices representative of natural water bodies under various light sources. Fundamental photolysis parameters such as molar absorption coefficient, quantum yield (QY) and first-order rate constants were determined. The photolysis decay rate was dependent on the protonation state of the molecule, pH of the water sample and dissolved organic matter. Natural organic matter was the most significant factor in the indirect photolysis of sulfonamides. Half-lives were in the range of minutes at 254 nm to days under natural sunlight. Under natural sunlight, all sulfonamides showed higher removal rates in natural waters implying that indirect photolysis is the predominant mechanism.     

A/O-MBR中硝化活性污泥的富集及其对氧氟沙星的降解作用

采用A/O-MBR系统,逐步提高进水氨氮浓度富集了硝化活性污泥(NAS),在此基础上,考察了COD、烯丙基硫脲(ATU)、氨氮初始浓度及氨氧化速率对NAS降解氧氟沙星(OFL)的影响。结果表明:富集的NAS的氨氧化速率达到了20 mg/(g SS·h)以上,对OFL具有明显降解作用;ATU存在条件下,COD对OFL的去除作用没有影响;提高初始氨氮浓度和NAS氨氧化速率均可以提高OFL降解量;初始氨氮浓度由50 mg/提升至150 mg/L时,OFL降解量由67.26 μg/g提高到82.11 μg/g;氨氧化速率由小于2.5 mg/(g SS·h)提升至大于20 mg/(g SS·h)时,OFL降解量由30.71 μg/g提高到75.16 μg/g。     

Production of the monoclonal antibody against tylosin for immunoassay of macrolide antibiotics in milk

The objective of the present study was to develop an immunoassay for multi-determination of the residues of four macrolide antibiotics in milk. Tylosin was derivatized with 6-aminohexanoic acid to synthesize a hapten that was used to produce the monoclonal antibody. The obtained monoclonal antibody simultaneously recognized tylosin, acetylisovaleryltylosin, tilmicosin and desmycosin with crossreactivities of 100%, 91%, 49% and 76%, respectively. Then an indirect competitive immunoassay was developed to determine the four analytes in milk simultaneously. The limits of detection for the four analytes were in the range of 5.5–11.7 ng/mL depending on the compound. The recoveries of the four analytes from fortified blank milk were in the range of 78%–96% with coefficients of variation lower than 11.4%. The developed immunoassay could be used as a practical tool for rapid screening the residues of the four anlytes in milk.     

Pollution characteristics of 23 veterinary antibiotics in livestock manure and manure-amended soils in Jiangsu province,China

The aim of this study was to investigate the pollution characteristics of typical veterinary antibiotics in manure and soil of livestock farms in Jiangsu province. This investigation employed solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A total of 53 manure and 50 amended soil samples from 16 livestock farms in Jiangsu province were collected for analysis. In the manure samples, the highest detected frequencies and concentrations were those of tetracyclines (TCs, 54.1 ± 5775.6 μgkg^?1), followed by fluoroquinolones (FQs, 8.4 ± 435.6 μgkg^?1), sulphonamides (SAs, 3.2 ± 5.2 μgkg^?1) and macrolides (MACs, 0.4 ± 110.5 μgkg^?1). Statistical analysis was used to illuminate the pollution characteristics of 23 veterinary antibiotics for various animal types and different regions in Jiangsu province. The results showed that the pollution level in cow manure was relatively lower compared with pig and chicken manure due to the relative restriction of medication. Furthermore, contamination was serious in amended soil from chicken farms. The pollution level in manure among different regions was higher to the south and north compared with the centre of the region. The same outcome was found for soil. Antibiotic residues in organic fertilizer were also investigated in this study. We found that although the detected concentration was lower in organic fertilizer than in fresh manure, detection frequencies (10–90%) were high, especially for roxithromycin (90%) in MACs (30–90%). This finding suggests attention should be paid to the pollution levels in organic fertilizer. This study is the first extensive investigation of the occurrence and distribution of many kinds of typical veterinary antibiotics in manure and soil from livestock farms of Jiangsu province. This investigation systematically assesses veterinary antibiotics usage and related emissions in southeast China.     

三峡库区主要水域典型抗生素分布及生态风险评估

为评价三峡库区主要水域典型抗生素的污染状况和生态风险,利用固相萃取-高效液相色谱-串联三重四极杆质谱联用法（SPE-HPLC-MS/MS）,分析三峡库区长江干流和6条支流表层水体中6类28种抗生素的质量浓度,根据欧盟环境风险评价方法计算RQ_S（风险商值）及RQ_sum（联合风险商值）,并按照Hernando等提出评级方法评价研究区域的生态风险等级.结果表明:三峡库区7条河流共检出4类10种抗生素,质量浓度范围为0.6~218.0 ng/L,其中除OFX（氧氟沙星）和CAP（氯霉素）外,其余8种[SDI（磺胺嘧啶）、SMX（磺胺甲唑）、SMZ（磺胺二甲嘧啶）、ERM（红霉素）、ROM（罗红霉素）、TYL（泰乐菌素）、FF（氟苯尼考）、LIN（林可霉素）]均为畜禽药品,并且FF、LIN在我国畜禽药品中使用量排名居前五位.7条河流抗生素RQ_sum由高到低依次为濑溪河>琼江>綦江>碧溪河>嘉陵江>长江>乌江,其中,濑溪河RQ_sum高达5.532,SMX、ERM和OFX均为高风险,说明其对濑溪河水体中相应的水生生物表现出较高的毒性风险;琼江、綦江、碧溪河和嘉陵江的RQ_sum均处于1~2之间,表现出较高生态风险,但4条河流检出抗生素的单个RQ_S均小于1,处于低风险;长江的RQ_sum为0.605,检出抗生素中TYL、ERM和ROM处于中风险,其余为低风险;乌江的RQ_sum为0.013,检出抗生素均处于低风险,说明水体受人类活动干扰最小.研究显示,三峡库区主要水域中抗生素含量略低于其他水域,但应进一步强化对畜禽养殖行业抗生素使用的监管,开展畜禽粪污还田技术规范中抗生素含量限制的相关研究.      

加速溶剂萃取-固相萃取-高效液相色谱/三重四级杆质谱法测定土壤中6种喹诺酮类抗生素残留

为测定污染土壤中的6种低残留喹诺酮类抗生素(氧氟沙星、培氟沙星、恩诺沙星、环丙沙星、诺氟沙星、恶喹酸),全面优化了一种联合加速溶剂萃取(ASE)、固相萃取(SPE)和高效液相色谱/三重四级杆质谱(HPLC/MSMS) 3种检测技术的分析方法。样品采用甲醇和0.1 mol/L EDTA-McIlvaine缓冲液(1∶1)进行加速溶剂萃取,经Bond Elut Plexa型HLB固相萃取小柱富集纯化,土壤中6种喹诺酮类抗生素的基质效应因子控制在0.84～1.04。在0.2～100.0μg/L(以恶喹酸计)质量浓度范围内,目标化合物的线性关系良好(r>0.999),6种目标化合物的检出限为0.09～0.75μg/kg,加标回收率为60.9%～89.9%。该方法自动化程度和准确度较高,可极大程度地降低基质效应,提高测定方法的灵敏度,适用于土壤中喹诺酮类抗生素残留的检测。