南方典型水源地及水产养殖区抗生素的复合污染特征及生态风险

抗生素作为生长促进剂和疾病预防控制药物在水产养殖领域得到广泛应用,目前在许多环境水体中检测到不同类型的抗生素。环境中抗生素的残留问题也是目前环境研究的热点问题之一。本研究选择南方某市8个水源地和5个典型水产养殖区作为研究对象,采用固相萃取、高效液相色谱串联三重四级杆质谱联用仪方法,调查了32种常用抗生素在水体中的含量水平和空间分布特征,揭示了抗生素的来源,并对其生态风险进行了评价。水源地共检出12种抗生素,浓度范围为0.12～44.6 ng·L~(-1),以磺胺甲噁唑含量最高;水产养殖区检出14种抗生素,浓度范围为0.95～716 ng·L~(-1),以氯四环素检出浓度最高。整体上水产养殖区抗生素的浓度高于水源地。抗生素浓度与环境因子的冗余分析表明,水产养殖和生活污水排放是水体中抗生素的主要来源。对检出的13种抗生素进行生态风险评价,单一抗生素而言,环丙沙星、氧氟沙星、磺胺嘧啶、氯四环素和脱水红霉素的风险商值大于0.01而小于0.1,表现为低风险。总抗生素风险商值加和在大部分水源地大于0.01而小于0.1,表现为低风险;总抗生素风险商值加和在2个水产养殖区大于0.1,表现为中等风险,水产养殖区抗生素的长期生态风险应该引起关注。     

Occurrence and fate of antibiotics in advanced wastewater treatment facilities and receiving rivers in Beijing,China

The occurrence and removal of 13 antibiotics were investigated in five wastewater treatment plants （WWTPs） with advanced wastewater treatment processes in Beijing, China. Most of the target antibiotics were detected in the secondary and tertiary effluents, with the concentrations of 4.8-1106.0 and 0.3-505.0ng·L^-1. Fluoroquinolone antibiotics showed relatively high concentrations in all samples （782-1814ng·L^-1）. Different tertiary treatment processes showed discrepant antibiotics removal performances. Ozonation process was found more effective in removing target antibiotics compared to the coagulation-flocculation-sedimentation process and sand filtration process. Investigation of the target antibiotics in three typical urban rivers in Beijing was carried out to understand antibiotics occurrence in surface water environment. Eight antibiotics were detected in the studied rivers, with highest concentration of antibiotics in the fiver which was mainly replenished by reclaimed water. This study showed the necessity of employing more effective advanced treatment facilities to further reduce the discharge amount of antibiotics.     

Occurrence and fate of typical antibiotics in wastewater treatment plants in Harbin,North-east China

• The concentration distributions and removals of 12 antibiotics were investigated. • Macrolides and fluoroquinolones presented relatively higher concentrations. • The removal of antibiotics did not differ among the different treatment processes. As a new pollutant, antibiotics in the environment and their removal in wastewater treatment plants (WWTPs) have gained considerable attention. However, few studies investigated antibiotics in the north-eastern areas of China. By employing high-performance liquid chromatography-tandem mass spectrometry, the concentration distribution and removal of 12 antibiotics belonging to four types (cephalosporins, sulfonamides, fluoroquinolones, and macrolides) were investigated in influents and effluents as well as the removal efficiencies of four typical treatment processes in 18 wastewater treatment plants of Harbin City, north-eastern China. Macrolides and fluoroquinolones presented relatively higher detection concentrations and rates both in the water and in the sludge phases. Sulfonamides and cephalosporins displayed higher detection concentrations in the water phase. The representative antibiotics in influents and effluents included ROX, NOR, OFL, SMX, AZI, and CLA, with detection rates above 95%. The detection rates of the other six antibiotics exceeded 30%. In the sludge, the other five antibiotics, except SMX, presented relatively higher detection concentrations and rates, with detection rates greater than 95%. For cephalosporin, the detection rates of CTX and CFM in the sludge were 0. The removal efficiencies for the 12 antibiotics differed greatly, with average values ranging from 30% to 80% and the highest values for cephalosporin. The removal of antibiotics did not differ significantly among the four different treatment processes.     

基于小流域尺度的目标抗生素排放量估算方法——以梅江流域为例

抗生素的大量使用和排放造成的环境污染和生态风险问题日益突出,抗生素排放量的估算是评价流域内抗生素污染程度的重要指标,但目前抗生素排放量估算方法尚不完善。本研究以梅江流域为例,建立了适合小流域尺度的典型抗生素排放量估算方法,计算了四环素类抗生素(TCs)向不同环境相的排放量并分析了其主要来源。结果表明:2016年梅江流域TCs排放量为8 558.1 kg,不同行政区抗生素排放量差异较大,其中梅江镇受人口密度及养殖密度影响,抗生素排放量最大,高达1 224.4 kg;同时流域内不同抗生素的排放量也有所不同,其大小顺序为强力霉素(DXC)土霉素(OTC)四环素(TC)金霉素(CTC);TCs受排放源、排放途径等因素影响,以进入环境水相及土壤相为主,其中进入水相中的抗生素主要来自人类及生猪粪便,进入土壤相中的抗生素主要来自生猪及三黄鸡粪便。梅江小流域抗生素具有潜在的生态风险,应加强抗生素使用管理。该研究为我国小尺度流域目标抗生素排放量的估算提供了十分有效的方法。     

Simultaneous quantification of several classes of antibiotics in water,sediments, and fish muscles by liquid chromatography–tandem mass spectrometry

Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments, and fish muscles were developed. In water samples, drugs were extracted with solid-phase extraction (SPE) by passing 1000 mL of water through hydrophilic lipophilic balanced (HLB) SPE cartridges. Sediment samples were solvent-extracted, followed by tandem SPE (strong anion exchange (SAX) + HLB) clean-ups. Fish muscles were extracted by a mixture of acetonitrile and citric buffer (80:20, v/v) solution, and cleaned by SPE. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM) detection was employed to quantify all compounds. The recoveries for the antibiotics in the spiked water, sediment, and fish samples were 60.2%–95.8%, 48.1%–105.3%, and 59.8%–103.4%, respectively. The methods were applied to samples taken from Dianchi Lake, China. It showed that concentrations of the detected antibiotics ranged from limits of quantification (LOQ) to 713.6 ng·L^-1 (ofloxacin) in surface water and from less than LOQ to 344.8 μg·kg^-1 (sulphamethoxazole) in sediments. The number of detected antibiotics and the overall antibiotic concentrations were higher in the urban area than the rural area, indicating the probable role of livestock and human activities as important sources of antibiotic contamination. In fish muscles, the concentration of norfloxacin was the highest (up to 38.5 μg·kg^-1), but tetracyclines and macrolides were relatively low. Results showed that the methods were rapid and sensitive, and capable of determining several classes of antibiotics from each of the water, sediment, and fish matrices in a single run.     

畜禽养殖过程抗生素使用与耐药病原菌及其抗性基因赋存的研究进展

兽用抗生素在提高畜禽生产性能、防治疾病方面发挥着重要作用,目前全球超过一半以上抗生素用于畜禽养殖,畜禽养殖源耐药病原菌、抗性基因及其传播风险愈益得到人们的重视。我国是畜禽养殖和抗生素使用大国,但兽用抗生素使用、病原菌耐药水平及其抗性基因类型等数据却较为缺乏,不利于今后畜禽养殖源耐药病原菌及其传播风险的控制。因此,本文通过文献调研,对我国和主要发达国家的兽用抗生素使用情况、畜禽养殖源耐药病原菌及其携带的抗性基因、基因移动元件以及向环境传播的途径进行分析、总结,以期为规范合理用药、降低耐药病原菌及其抗性基因传播风险,建立从畜禽养殖场至公共环境全过程的抗性污染控制链条提供借鉴。     

北江流域抗生素污染水平和来源初探

北江是发源于湖南(武水)和江西(浈水),汇于广东韶关,流经广东全境并入海的三大河流之一。为了解整个北江抗生素污染情况,共设置44个采样点,并采集了河水及部分沉积物样品,较全面地分析了各样品中12种典型抗生素含量并初步探究了其污染来源。研究发现,包括北江源头在内的全河段均有抗生素的检出,5类抗生素在表层水和沉积物中的平均浓度分别为77.8 ng·L~(-1)和3.6 ng·g~(-1)。其中,大环内酯类污染最为严重,其含量范围为11.7~114.6 ng·L~(-1)和0~435.3 ng·g~(-1),远高于其他类抗生素。表层水中磺胺类的磺胺甲恶唑和氯霉素类的检出率达100%,其中以磺胺甲恶唑(14.7 ng·L~(-1))和阿奇霉素(25.0 ng·L~(-1))为主,而沉积物中以阿奇霉素(35.9 ng·g~(-1))、氧氟沙星(5.4 ng·g~(-1))和四环素(3.3 ng·g~(-1))为主。由于流域污染源种类和数量不同,各抗生素在北江中的分布也存在差异。表层水中抗生素含量水平表现为下游高于上中游,在沉积物中则主要集中于中、下游之间河段。这反映了人类活动强度对北江抗生素污染的直接影响。     

Effects of pitamin on growth performance, carcass characteristics and cecal microflora of broiler chicken

The aim of this study is to determine the effect of dietary pitamin as an antibiotic replacement in broiler chicken. The treated groups were as follows: 1) the control, 2) the antibiotics (8 mg of avilamycin kg(-1) of diet) and 3) the pitamin (70 mg of pitamin kg(-1) of diet) groups. Body weight gain, feed intake, and feed efficiency were significantly higher in the pitamin group than in the antibiotics and control groups (p<0.05). Carcass weight, dressing percentage, and the weight of breast and thigh muscle recorded significantly higher levels in the pitamin group as compared to the other groups (p<0.05). The addition of pitamin to the diets for broilers reduced abdominal fat by 23.35% and stimulated the growth of the thymus, the spleen, and the bursa of Fabricius. TAG levels of the pitamin group declined by 12.03 and 10.45% as compared to the control and antibiotics groups, and their TC levels were reduced by 15.17 and 14.39%, and LDL. C levels were reduced by 10.56 and 11.24%, respectively. Serum IgG was increased significantly by 137.43 and 36.80% in the pitamin group as compared to the control and antibiotics groups, respectively (p<0.05). The numbers of Bifidobacterium and Lactobacillus on the cecum digesta were significantly higher in the pitamin group than in the antibiotics and control groups and the numbers of Escherichia coli and Salmonella tended to be reduced (p<0.05). In conclusion, when Korean red pine bark extract, pitamin, was added to the broiler diets at a concentration of 70 mg of pitamin kg(-1) of diet, it resulted in better growth performance as compared to the antibiotics by improving immunity and the cecal beneficial microfloral population.     

我国养猪业废弃物中四环素类、磺胺类抗生素及相关抗性基因污染研究进展

我国是世界养猪第一大国,生猪饲养量和猪肉产量均位居世界第一。养猪业每年所产生的粪便、废水中含有大量畜用抗生素及其代谢产物,使养猪业废弃物成为环境中重要的抗生素污染源之一,随之产生的抗性基因污染及传播问题也不容忽视。本文结合近年来国内外的研究数据,对我国养猪业废弃物中四环素类、磺胺类抗生素及其相关抗性基因的检测方法、污染状况及影响抗性基因传播的因素进行了分析,并基于控制我国养猪行业抗生素及抗性基因污染的目的,提出了今后的研究重点。     

Microwave-assisted synthesis of biodegradable and antibacterial thiophene,furan and thiazole derivatives

Environmental Chemistry Letters - The rise of bacterial resistance to common clinical antibiotics is calling for alternative techniques to synthesize antibacterial drugs with high biodegradability....     

Mitigation of antibiotic resistance using probiotics,prebiotics and synbiotics. A review

Environmental Chemistry Letters - Multi-drug resistant microbes are becoming a serious threat to health security and the economy. Antibiotic resistance results from the overuse of antibiotics for...     

Antibiotic distribution,risk assessment,and microbial diversity in river water and sediment in Hong Kong

Environmental Geochemistry and Health - For the past fewer years, environment antibiotic residues have got more and more attention. The occurrence and distribution of eight common antibiotics,...     

抗生素在地下水系统中的环境行为及生态效应研究进展

抗生素在环境中的残留已引起广泛关注。随着对地下水污染的报道日益增多,抗生素对地下水系统的潜在影响不容忽视。本文系统地阐述了地下水中抗生素的来源、污染水平及迁移转化规律,总结了抗生素对地下水微生物群落的影响以及抗生素诱导产生的抗性基因的潜在污染趋势。因地下水赋存隐蔽,一旦污染难以及时察觉,抗生素进入地下水系统后易长期残留。目前,针对抗生素及抗性基因在地下水系统中的环境行为及生态效应研究还十分有限,本文据此指出了当前形势下开展相关研究的必要性,并对今后的研究方向进行了展望。     

抗生素与LED209对大肠杆菌的联合毒性机制

抗生素是一把双刃剑,在提高医疗水平的同时会促进抗性基因的发展。群体感应抑制剂(quorum sensing inhibitors,QSIs)可有效地避免这一缺陷,有望成为抗生素的替代品而与抗生素有环境共存的可能,但目前尚缺乏它们的联合毒性机制及其相关的环境风险评价研究。本文以大肠杆菌为受试生物,测定了群体感应抑制剂N-苯基-4-(3-苯基硫代脲基)苯磺酰胺(LED209)与5种抗生素的单一和二元联合毒性。结果表明,LED209与5种抗生素的联合毒性作用均表现为拮抗,推测是LED209通过影响鞭毛合成,减弱了抗生素对大肠杆菌的生物有效性;同时通过拆分分子式,发现了拮抗作用可能源于LED209分子式中的含苯基和硫代脲基的L1分子,因此建议未来在LED209药物优化时,应尽可能的保留L1部分的基团,从而保证混合体系的最小环境风险。本研究不仅为联合用药提供依据,而且从环境风险评价角度为抗生素替代品LED209的结构优化提供理论指导。     

光催化降解对抗生素藻类毒性效应影响研究进展

抗生素滥用带来环境中残留抗生素及其抗性基因的问题,近年来已成为全球关注的热点问题.光催化氧化技术是当前研究领域广泛采用的有效降解水环境中残留抗生素的热门方法;但光催化氧化无法使水环境中抗生素完全矿化,存在生态风险,探明光催化降解抗生素对其藻类毒理效应影响及内在机制,对研发高效、安全的光催化技术具有重要意义.本文在总结水...     

Adsorption behavior of antibiotic in soil environment: a critical review

Antibiotics are used widely in human and veterinary medicine, and are ubiquitous in environment matrices worldwide. Due to their consumption, excretion, and persistence, antibiotics are disseminated mostly via direct and indirect emissions such as excrements, sewage irrigation, and sludge compost and enter the soil and impact negatively the natural ecosystem of soil. Most antibiotics are amphiphilic or amphoteric and ionize. A non-polar core combined with polar functional moieties makes up numerous antibiotic molecules. Because of various molecule structures, physicochemical properties vary widely among antibiotic compounds. Sorption is an important process for the environment behaviors and fate of antibiotics in soil environment. The adsorption process has decisive role for the environmental behaviors and the ultimate fates of antibiotics in soil. Multiply physicochemical properties of antibiotics induce the large variations of their adsorption behaviors. In addition, factors of soil environment such as the pH, ionic strength, metal ions, and organic matter content also strongly impact the adsorption processes of antibiotics. Review about adsorption of antibiotics on soil can provide a fresh insight into understanding the antibiotic-soil interactions. Therefore, literatures about the adsorption mechanisms of antibiotics in soil environment and the effects of environment factors on adsorption behaviors of antibiotics in soil are reviewed and discussed systematically in this review.     

基于高通量分析方法的长江干流重庆段抗生素种类特征及来源初探

采用高通量分析方法对长江干流重庆段11个流域断面、2个市政污水处理厂进水和6个养殖场废水的潜在抗生素进行筛查,并结合抗生素使用调查探讨其来源。结果表明,(1)共检出83种抗生素,其中流域内检出36种,污水处理厂和养殖场废水中检出70种;磺胺间甲氧嘧啶检出率最高,在流域水体和废水的检出率分别为91%和55%,喹诺酮类是检出抗生素的主要类型;(2)长江干流重庆段下游检出抗生素数量高于上游检出抗生素;(3)有20种抗生素可能由上游携带和重庆市内排放2种方式进入流域,7种抗生素可能由上游携带入境,9种抗生素可能由重庆市内排放引入长江。     

抗生素抗性基因在环境中的来源、传播扩散及生态风险

近年来,由于抗生素的滥用首先诱导动物体内产生抗生素抗性基因(antib iotic resistance genes,ARGs),从而加速了抗性基因在环境中细菌间的传播扩散.目前,抗生素抗性基因作为一类新型环境污染物,在不同环境介质中的传播、扩散可能比抗生素本身的环境危害更大.本文针对抗生素抗性基因在地表水、地下水、医疗废水、城市污水处理厂、养殖场、土壤、沉积物以及大气环境中的来源、分布、传播情况以及国内外最新研究动态进行综述.分析了抗生素抗性基因在环境中的潜在传播途径及其可能影响因素,并指出光照,厌氧,高温处理可以有效遏制抗生素抗性基因在环境中的传播和扩散.揭示了抗生素抗性基因可能造成的生态风险,针对我国对该类污染物的研究现状,提出了今后的研究重点.     

Tetracycline antibiotics in the environment: a review

Tetracycline antibiotics are one of the primarily antibiotics groups used for veterinary purposes, for human therapy and for agricultural purposes. Amongst the different antibiotics used, more attention is paid to tetracycline’s as it exhibits serious environmental problems including ecological risks and human health damages. Due to their extensive usage, most of the actual evidence suggests that tetracycline antibiotics are omnipresent compounds found in different ecological compartments. After medication, more than 70 % of tetracycline antibiotics are excreted and released in active form into the environment via urine and feces from humans and animals. Their highly hydrophilic character and low volatility have resulted in significant persistence in the aquatic environment. Very few studies describe the fate and toxicity of tetracycline antibiotics in the environment. Here, we review several important issues with regard to: (1) the toxicity of these compounds on aquatic and terrestrial organisms; (2) their estrogenic effects; (3) their behavior in different ecological systems and; (4) the by-products generated during water treatment. These antibiotics residues promote the development of antibiotic resistant microorganisms, which can induce adverse effect to human health by increasing the risk of certain infections. Based on recent research results, the occurrence of tetracycline antibiotics in the environment inhibits the growth of some terrestrial and aquatic species. Besides, the residual concentrations of such drugs could affect steroidogenic pathway and consequently may cause endocrine disruption of aquatic species. Most of the wastewater treatment plants are not capable of removing effectively the tetracycline antibiotics. Therefore, there is a need to develop alternative processes to remove them from waters. Advanced oxidation processes have been proposed as alternative methods to ensure higher degradation and mineralization of tetracycline antibiotics are present in waters.