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Detection of 36 antibiotics in coastal waters using high performance liquid chromatography-tandem mass spectrometry 总被引：2，自引：0，他引：2
Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines (TCs), sulfanilamides (SAs), and quinolones (QLs). The method consists of solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, using electrospray ionization (ESI) in positive mode. The SPE was performed with Oasis HLB and Oasis MCX cartridges. Chromatographic separation on a C18 column was achieved using a binary eluent containing methanol and water with 0.1% formic acid. Typical recoveries of the analytes ranged from 67.4% to 109.3% at a fortification level of 100 ng/L. The precision of the method, calculated as relative standard deviation (RSD), was below 14.6% for all the compounds. The limits of detection (LODs) varied from 0.45 pg to 7.97 pg. The method was applied to determine the target analytes in coastal waters of the Yellow Sea in Liaoning, China. Among the tested antibiotics, 31 were found in coastal waters, with their concentrations between the LOD and 212.5 ng/L. These data indicate that this method is valid for analysis of antibiotics in coastal waters. The study first reports such a large number of antibiotics along the Yellow Sea coast of Liaoning, and should facilitate future comprehensive evaluation of antibiotics in coastal ecosystems. 相似文献
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应用广泛且具有毒性的有机磷酸酯(organophosphate esters,OPEs)类阻燃剂,通过水、气输送等多种途径进入海洋环境,可能会导致人类和海洋生物面临潜在的健康风险。因此,建立高效可靠的分析方法对于揭示OPEs在海洋环境中的赋存状况,评估其生态风险具有重要的科学意义。文章建立了同时测定沉积物中27种OPEs的超声提取、固相萃取(SPE)净化以及高效液相色谱-串联质谱(HPLC-MS/MS)检测的分析方法。结果表明:30mL乙酸乙酯(EA)和乙腈(ACN)混合溶剂(体积比为3︰7)的提取效果明显优于单独使用甲醇(MeOH)、二氯甲烷(DCM)、EA和ACN;用5mL EA经LC-C18固相萃取小柱洗脱两次回收率最好;以MeOH和含0.0025%甲酸的水溶液作为流动相时,质谱离子丰度最高。27种OPEs的线性范围为5~500 ng/g (R2>0.99),方法检出限(MDL)范围为0.004~1.250 ng/g,定量限(LOQ)为0.01~4.17 ng/g。三个加标水平(低、中、高)基质加标样品的平均回收率在45%~130%之间,相对标准偏差(RSD)最高11.0%,表明此方法可靠,精密度和灵敏度较高。采用优化的方法分析我国长江口、杭州湾入海口以及东海和黄海交界处海域表层沉积物中OPEs的含量,共检出了21种OPEs,浓度范围为9.83~48.70 ng/g,平均浓度为28.40 ng/g。该方法检测结果高效准确,可用于海洋沉积物中27种OPEs的同时测定。 相似文献
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基于等价分析法评估溢油事故的自然资源损害 总被引：2，自引：0，他引：2
尽管国际公约和许多国家立法已将海上溢油事故导致的自然资源损失列入索赔范围,然而,在量化和货币化损害以及确定索赔和修复范围等方面尚未建立被广泛接受的计算方法。生境等价分析(Habitat Equivalency Analysis,HEA)和资源等价分析(Resource Equivalency Analysis,REA)是美国和欧盟应用于评估自然资源损害的理论方法,二者的关键假设是受损的生态服务损失和修复计划的服务收益应当相等。HEA结果依赖于生态服务价值标尺选择、服务价值水平、恢复曲线形状、修复计划时长以及贴现率等;REA结果受死亡生物数量和年龄组成的影响。HEA和REA的非货币形式结果补偿的并非生态环境,而是人类社会福祉。目前,一些货币化损失的方法已被提出,然而传统经济学家和生态经济学家之间存在争议。美国部分法庭承认HEA和REA方法,其结果为法庭索赔提供数据支持。如果将生态学和经济学原理结合考虑,将能够促进等价分析法的深入发展,推动索赔工作更加有理有据。 相似文献
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Characteristics of nitrogen forms in the surface sediments of southwestern Nansha Trough,South China Sea 总被引：5，自引：0，他引：5
The area of the southwestern Nansha Trough is one of the most productive areas of the southern South China Sea.It is a typical semi-deep sea area of transition from shoal to abyssal zone.To understand distributions and roles of nitrogen forms involved in biogeochemical cycling in this area,contents of nitrogen in four extractable forms:nitrogen in ion exchangeable form(IEF-N),nitrogen in weak acid extractable form(WAEF-N),nitrogen in strong alkali extractable form(SAEF-N) and nitrogen in strong oxidation extractable form(SOEF-N),as well as in total nitrogen content(TN) in surface sediments were determined from samples collected from the cruise in April-May 1999.The study area was divided into three regions(A,B and C) in terms of clay sediment(<4 μm) content at <40%,40%-60% and >60%,respectively.Generally,region C was the richest in the nitrogen of all forms and region A the poorest,indicating that the finer the grain size is,the richer the contents of various nitrogen are.The burial efficiency of total nitrogen in surface sediments was 28.79%,indicating that more than 70% of nitrogen had been released and participated in biogeochemical recycling through sediment-water interface. 相似文献
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大连湾和杭州湾表层沉积物中多氯联苯和有机氯农药及风险评价 总被引：2，自引：0，他引：2
对大连湾与杭州湾沉积物样品中多氯联苯(Polychlorinated Biphenyls,PCBs)和有机氯农药(Organochlorine Pesticides,OCPs)进行了分析测定。结果表明,大连湾和杭州湾沉积物中PCBs的含量为0.72~14.87 ng/g和0.76~3.86 ng/g,其中3、4、5氯联苯比例较高,其和超过总含量的70%;OCPs的含量为2.98~32.23 ng/g和1.61~4.71 ng/g,其中主要成分为六六六(Hexachlorocyclohexanes,HCHs)和滴滴涕(Dichlorodiphenyldichloroethylenes,DDTs)。大连湾和杭州湾表层沉积物中HCHs主要来自农业使用,而且大连湾有新的DDTs输入,杭州湾表层沉积物中的DDTs则主要来自历史残留。生态风险评价的结果表明,PCBs几乎不会对研究区域产生生态风险,OCPs对杭州湾也不会造成潜在的生态风险,但大连湾的OCPs处于中等风险水平,应当引起关注。 相似文献
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本文建立了半透膜渗透装置(semi-permeable membrane device,SPMD)富集-超声萃取-凝胶渗透色谱净化-气相色谱法测定沉积物间隙水中多氯联苯(PCBs)的方法。比较了有机溶剂透析法与超声萃取法从膜袋内提取PCBs的回收率,发现超声萃取法在节省时间和溶剂方面有明显优势。应用凝胶渗透色谱分离与净化SPMD提取物,收集11—17min的流出液能达到最佳分离效果。基于此方法测定了大连湾沉积物间隙水中自由溶解态PCBs的含量(C_(W-SPMD)),同时又分析了沉积物中PCBs的总量(C_(SED))、间隙水中PCBs的含量(有机碳含量校正法,C_(W-SED))和间隙水中PCBs的总含量(离心法,C_(PW))。结果表明,C_(PW)值显著高于C_(W-SED)和C_(W-SPMD)值。因此,考虑到生物可利用性,无论采用沉积物中或者间隙水中的PCBs总量进行污染物生态风险评价均会造成风险被高估,建议采用间隙水中可溶解态含量。 相似文献
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Three extraction techniques have been recently used for the quantitative extraction of semi-volatile organic pollutants in sediments, i.e. accelerated solvent extraction (ASE), microwave assisted extraction (MAE) and ultrasonic assisted extraction (UAE). However, their extraction efficiencies have rarely been quantitatively compared using rigorous mathematical methods. In this paper, one-way analysis of variance (ANOVA) was employed to evaluate the performance of ASE, MAE and UAE in the overall extraction of PCBs, DDTs and HCHs by analysis of their recoveries from the Standard Reference Material IAEA-417, a sediment sample certified by many international laboratories. Conclusions were drawn at a significance level of P ≤ 0.05. No significant differences were found among the mean values for method recoveries using ASE, MAE and UAE. The mean values for real recoveries using ASE and MAE were nearly identical, but the real recovery using UAE was much lower. The concentrations of all PCBs, DDTs and HCHs except for CB52 and o,p′-DDT using UAE were the lowest. Comparing the results obtained using ASE with MAE, the concentrations of CB28, CB52, CB138, α-HCH, β-HCH, p,p′-DDE and p,p′-DDD were nearly identical, while the concentrations of other compounds were significantly different. Based on the low recoveries, it was concluded that UAE is a relatively inefficient extraction method, while ASE and MAE are equivalent methods. Taking into consideration the relative standard deviation (RSD) values, solvent volume, extraction time, and purchasing costs of the apparatus, MAE was considered superior to ASE for extraction of PCBs, DDTs and HCHs. 相似文献
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