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1.
气相色谱测定沉积物中多氯联苯的样品处理方法研究 总被引：1，自引：0，他引：1
通过比较密闭微波萃取、超声波萃取、索氏提取3种方法对沉积物中多氯联苯(PCBs)提取效率,对比浓硫酸和Florisil小柱两种净化方式的净化效果,在实验基础上建立了密闭微波萃取-Florisil小柱净化-气相色谱(ECD)测定沉积物中多氯联苯的分析方法,加标质量比为0.2ng/g时,其相对标准偏差(RSD)为2.19%～8.71%,回收率为77.3%～94.6%,检出限为0.027～0.064ng/g。采用该方法对威海湾养殖区沉积物中PCBs进行了监测,结果表明本方法适用于海洋沉积物样品中PCBs的测定。 相似文献
2.
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
3.
用氢氟酸刻蚀不锈钢丝制作了固相微萃取（solid-phase microextraction， SPME）纤维，与气相色谱（gas chromatography， GC）联用直接测定了海水水样中的痕量多氯联苯（polychlorinated biphenyls， PCBs），优化了萃取时间、萃取温度、搅拌速率、解吸温度和解吸时间对SPME的萃取效率的影响。本方法的线性范围可达两个数量级，PCB28和PCB52的线性范围是1.0~100.0 ng/L，其他8种PCBs的线性范围是0.5~50.0 ng/L（除PCB198外，r2均在0.99以上），检出限为0.01~0.10 ng/L。单个纤维间及纤维与纤维间的相对标准偏差分别为2.4%~7.2%和4.9%~8.7%。实际海水样品的加标回收率为80.9%~106.0%。微萃取纤维机械强度高、耐海水腐蚀、寿命长、制作成本低，该方法适用于测定海水水样中的痕量PCBs。 相似文献
4.
亚临界流体萃取高效液相色谱法测定鱼肉中丙酸睾酮残留 总被引：1，自引：0，他引：1
采用亚临界1,1,1,2-四氟乙烷(R134a)萃取技术作为样品的前处理技术,建立亚临界流体萃取高效液相色谱法测定鱼肉中丙酸睾酮残留量的新方法。在对添加了丙酸睾酮的罗非鱼肌肉样品亚临界R134a萃取单因素实验的基础上,通过正交实验对萃取条件进行了优化,结果为:萃取压力14MPa,萃取温度23℃,R134a流量1.0L/min(标态),静态萃取30min,动态萃取40min,共溶剂甲醇添加量2mL,收集液为甲醇。收集液经石油醚纯化后,用高效液相色谱检测。在最优条件下,方法回收率大于90%、相对标准偏差(RSD)小于5%。最后,对实际样品进行实际检测,鱼肉冷冻干燥样品中丙酸睾酮的残留量为1.37μg/g。本方法首次利用亚临界R134a萃取作为兽药残留分析样品的前处理技术,萃取压力和萃取温度都比较低,易于大规模推广应用。 相似文献
5.
从样品采集与保存、样品前处理、多环芳烃的检测3个方面介绍了测定海水和海洋沉积物中多环芳烃的步骤和最新进展.对目前较为常用的几种样品前处理方法,如液-液萃取、固相萃取、固相微萃取、索氏提取、超声提取、微波萃取、超临界流体萃取、加速溶剂萃取;以及检测方法,如气相色谱-质谱法、高效液相色谱法等作了详细介绍,比较了各自的优缺点.对目前较为常用的2种多环芳烃的来源解析方法(分子指纹法和同位素指纹法)的相关研究进展进行了总结. 相似文献
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7.
元素分析仪快速测定海洋沉积物TOC和TN的条件优化 总被引：4，自引：0，他引：4
报道了在优化样品前处理、燃烧温度、最小加氧量和最佳称样量的基础上,综合构建优化了直接固体进样varioMACRO cube元素分析仪同时测定海洋沉积物样品中总有机碳(TOC)和总氮(TN)的条件,即准确称取20~30 mg沉积物样品用1 mol/L盐酸除去无机碳后,直接进样在燃烧管温度960℃,次级燃烧管温度830℃,还原管温度900℃,氦气压力0.12 MPa,流量600 mL/min,氧气压力0.20 MPa,加氧量22.5 mL仪器条件下,用标准曲线法峰面积获取TOC和TN浓度。结果表明,海洋沉积物中TOC和TN测定的检出限分别为0.0508%和0.0146%,回收率分别为97.7%~100.9%和97.2%~101.1%,对4个实际外海沉积物样测定总有机碳和总氮结果的相对标准偏差(RSD)为0.83%~3.06%和1.33%~3.49%(n=12)。该方法操作简便快速、灵敏度高,具有较好的精密度和准确度,可准确可靠地用于海洋沉积物中总有机碳和总氮含量的测定。 相似文献
8.
高效液相色谱法测定海水中溶解态游离氨基酸 总被引：1，自引：0，他引：1
采用邻苯二甲醛柱前衍生-高效液相色谱-荧光检测器(OPA—HPLC-FLD)联用技术分离测定了海水中的14种主要溶解游离氨基酸(DFAA),通过邻苯二甲醛—3-巯基丙酸(OPA—3-MPA)柱前衍生后,在XDB-C18柱上分离。不同氨基酸测定的精密度(RSD)为1.62%~3.80%,检测限为11.4~69.7 ng.L-1,海水加标回收率在92%~110%之间。利用该方法测得青岛近海表层海水中氨基酸浓度为0.015~0.284μmolL-1。 相似文献
9.
选择蒽、9-甲基蒽和9,10-二甲基蒽作为模型化合物,以李村河口区沉积物为培养基质,进行实验室好氧微生态培养,通过超声萃取-柱层析-气相色谱法测定目标污染物浓度随培养时间的变化,研究了它们在自然菌群作用下的生物降解行为。测定方法的基质加标回收率在66.20%~82.95%之间,相对标准偏差在3.34%~6.19%之间。6个月的好氧生物降解实验表明,沉积物中本底蒽由32.88 ng.g-1降到32.32 ng.g-1,降解率仅为1.70%;而在添加了蒽的沉积物样品中其浓度由170.40 ng.g-1降到151.36 ng.g-1,降解率高达11.17%;加入的9-甲基蒽和9,10-二甲基蒽的浓度也分别由133.84 ng.g-1和144.26 ng.g-1减少至122.52 ng.g-1和135.13 ng.g-1,降解率分别达到8.46%和6.33%。相同条件下三种有机污染物的不同降解速率表明,9,10位取代使得蒽在沉积环境中更加持久,自然降解速率更慢 相似文献
10.
氟喹诺酮类(FQs)药物是一种广泛使用的人工合成类抗生素,存在于水体、沉积物等各种环境介质中,并在水生生物体内得到富集,对人类健康和全球生态系统的可持续发展有重要的影响。环境中FQs残留的分析检测是了解其环境生物地球化学行为和潜在生态环境风险的基础,本文系统总结了近几年海洋水体、沉积物和生物体样品中FQs的残留特征、样品前处理与检测技术,在此基础上,前瞻分析了海洋环境中FQs残留分析检测技术的发展趋势。分析表明,FQs的分离富集和测定必须充分考虑FQs的物理化学性质和样品成分的复杂性。海水样品准备应注意过滤膜的选择和pH的调节;沉积物和生物体的样品准备应考虑水分、萃取溶剂、基质效应和pH的影响,并使用超声萃取。固相萃取、QuEChERS萃取、磁性固相萃取是分离富集FQs较常用的方法,吸附剂、淋洗溶液和洗脱溶液的选择和优化是提高样品回收率的关键。FQs的检测大多通过液质联用或液相色谱结合荧光检测器进行,其中色谱柱的选择、离子对试剂的添加和进样pH值的调整都是优化的关键因素。研究指出海洋领域FQs在线自动SPE技术的开发以及新型萃取吸附剂的研制应在未来研究中被重点关注。 相似文献
11.
东海表层水体中的多环芳烃及其沉积通量估算 总被引：2，自引：0，他引：2
以东海陆架水体中溶解态多环芳烃(PAHs)含量为基础,引入颗粒相-水相间的物质吸附系数(Koc)计算悬浮颗粒物中PAHs有机碳归一化含量,结合陆架沉积物有机碳的年埋藏通量,估算东海陆架沉积物中PAHs沉积通量。结果显示:水体中溶解态的15种PAHs总含量为(701±392)ng/L,变化范围为412~1 032ng/L,PAHs组成以3环为主。计算得到的悬浮颗粒物中15种PAHs有机碳归一化含量为20~28μg/g,对应的PAHs沉积通量为150~210t/a。估算结果与实测沉积物中PAHs含量和沉积通量结果基本吻合,表明实验室模拟实验获取的化合物Koc值适用于东海颗粒相-水相间的分配模型,证实悬浮颗粒物有机碳含量在控制PAHs两相分布过程中起着重要作用。同时,该方法为海洋沉积物中PAHs沉积通量的估算提供一种新途径。 相似文献
12.
Evaluation of atmospheric transport as a nonpoint source of polycyclic aromatic hydrocarbons in marine sediments of the Eastern Mediterranean 总被引：1，自引：0，他引：1
Coastal marine sediment, air and seawater samples were collected at six sampling stations in the Eastern Mediterranean Sea distant from pollutant point sources. All sediment samples were analyzed to determine polycyclic aromatic hydrocarbon (PAH), black carbon (BC) and organic carbon (OC) contents. The PAH contents of gaseous and seawater samples of the study were determined in order to evaluate the role of air–sea exchange as PAH nonpoint source to the marine sediments. The average concentration of the total PAHs (∑PAHs) in the sediments varied from 2.2 to 1056.2 ng g−1 dry weight. The average BC and OC contents varied from 0.3 to 5.6 and from 2.9 to 21.4 mg g−1 dry weight, respectively. ∑PAH concentration in the marine atmosphere varied from 20.0 to 83.2 ng m−3. Air–water exchange flux (FA–W) estimation has indicated air transport as a significant source of PAHs to pristine marine sediments of Eastern Mediterranean. In addition, the significant correlation between the PAHs and the organic and soot carbon content further suggests the importance of atmospheric input of PAHs to the sediments. 相似文献
13.
白令海和楚科奇海表层沉积物中多环芳烃降解微生物多样性 总被引：4，自引：0，他引：4
为了研究白令海(海盆及陆架)至楚科奇海陆架表层沉积物中多环芳烃(PAHs)降解菌的多样性,并获得新的PAHs降解菌资源。在GC-MS分析沉积物中PAHs种类和含量的基础上,以萘、菲和芘的混合物为唯一碳源和能源对表层沉积物样品进行富集,通过平板分离鉴定可培养菌株,并验证其降解能力;同时利用变性梯度凝胶电泳(DGGE)和Illumina高通量测序技术分析降解菌群结构。GC-MS测定结果表明,14个表层沉积物中PAHs总干质量介于32.99~276.97ng/g。富集菌群中共分离获得51株可培养细菌,平板纯培养、PCR-DGGE及Illumina测序结果均表明,菌群中优势的降解菌是γ-proteobacteria的Marinobacter,Pseudoalteromonas,Pseudomonas和Actinobacteria门的Dietzia菌。此外,Illumina测序结果还表明14个降解菌群在菌群结构组成上,可分为海盆区和陆架区两种类群;同时检测到一些低丰度的海洋专属PAHs降解菌,如Cycloclasticus,Alteromonas和Neptunomonas等。本文结果将加深对白令海及楚科奇海表层沉积物中PAHs降解菌资源与生物多样性的认识。 相似文献
14.
The PAH composition of surface sediments from Stagnone coastal lagoon, Marsala (Italy) 总被引：2，自引：0，他引：2
Loredana Culotta Concetta De Stefano Antonio Gianguzza Maria Rosaria Mannino Santino Orecchio 《Marine Chemistry》2006,99(1-4):117
This paper examines the presence, distribution, nature and sources of 22 Aromatic Hydrocarbons (PAHs), which are important environmentally and toxicologically, in sediments from the Stagnone coastal lagoon at Marsala (Italy). Analysis was performed by gas chromatography/mass spectrometry (GC/MS) with selected ion monitoring (SIM). The total concentration of polycyclic aromatic hydrocarbons ranged from 72 to 18381 μg/kg of dry matrix. The relative standard deviation (RSD) of the replicates on the concentrations of individual compounds ranged from 5% to 20%. The accuracy of method was estimated by analyzing “blank” samples added of known quantities of analytes and the recover percentage was 88 ± 9%. The detection limit (LOD) of analytical procedure was less than 0.2 μg/kg d.w. for all analytes. The quantification limit (LOQ) of analytical procedure was less than 0.7 μg/kg d.w.The resulting distributions and weight ratios of specific compounds are discussed in terms of sampling location and origin of organic matter. A comparison with other studies of total PAHs suggests that the levels are within the concentration ranges already reported by other authors. From an eco-toxicological point of view, total PAH concentrations at seven out of the eight sites studied represent a relatively clean environment when compared to other sites.Organic matter content and PAH concentrations were found to be correlated and the compounds present in Stagnone sediments were shown to be mainly of pyrolitic origin, while a negligible quantity of PAHs may derive from biogenic sources since all the sediments contain perylene traces. There is no evidence of coal-tar contamination.Cluster analysis was carried out in order to discriminate between different PAH origins. 相似文献
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2007年11-12月采集福建和粤东近岸海域的沉积物样品,对沉积物中的PAHs含量、组成进行研究,分析了研究海域沉积环境中PAHs的分布特征、来源,并利用Long等人建立的评价模式对PAHs的生态风险进行了评价.研究结果为深入研究海域沉积环境中PAHs的地球化学行为提供了科学依据.结果表明：研究海域PAHs的含量范围为52.93-398.50 ng/g,平均值为170.30 ng/g,研究发现闽江径流是影响海区沉积物中PAHs含量分布的重要因素之一.通过不同环数PAHs的相对丰度和异构体比值分析,对研究海区沉积物中PAHs进行了溯源分析,发现厦门以北海域沉积物中的PAHs主要来自化石燃料燃烧,而厦门以南海域则主要来源于石油污染.生态风险评价结果显示,研究海域PAHs对生物体极少产生负面生态效应,潜在生态风险很小. 相似文献
16.
Ying Wang Xing Liu Yi Cong Jin Fei Juying Wang Dian Zhang Liang Liu Jingli Mu Ziwei Yao 《海洋学报(英文版)》2020,39(12):95-105
Parent and alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs), which are a class of important toxic components of crude oil especially in the marine environment, exhibit adverse effects on aquatic life and potentially pose a human health risk. However, the lack of chronic toxicity data is one of the hindrances for alkyl-PAHs when assessing their ecological risks. In this study, predicted no-effect concentrations (PNECs) in seawater and marine sediment for ten parent- and alkyl-PAHs were derived by applying species sensitivity distributions (SSDs) and quantitative structure?activity relationships (QSARs). The local area, Dalian Bay, where an oil-spilled accident happened in 2010, was chosen as a case site to assess ecological risks for ten PAHs in surface seawaters and marine sediments. Their PNECs in seawater and sediment for protecting aquatic organisms in marine ecosystems were calculated and recommended in the range of 0.012?2.79 μg/L and 48.2?1337 ng/g (dry weight), respectively. Overall, the derived PNECs for the studied PAHs in seawater and marine sediment were comparable to those obtained by classical methods. Risk quotient results indicate low ecological risks to ecosystems for ten parent- and alkyl-PAHs in surface seawaters and surface sediments from the Dalian Bay. These findings provide a first insight into the PNECs and ecological risks of alkyl-PAHs, emphasizing the role of the computational toxicology in ecological risk assessments. The use of QSARs has been identified as a valuable tool for preliminarily assessing ecological risks of emerging pollutants, being more predictable of real exposure scenarios for risk assessment purposes. 相似文献
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研究了台州湾海域海水和表层沉积物中15种多环芳烃(PAHs)的浓度水平,评价了表层沉积物对多环芳烃的富集规律,探讨其可能来源.结果表明,表层沉积物中PAHs的浓度范围为85.4 ～ 167.6 ng/g,平均值为138.62 ng/g,总多环芳烃的最大值是椒江码头.表层沉积物中二环、三环、四环、五环和六环多环芳烃占总多环芳烃的百分含量平均值分别为7.8 %,42.1 %, 33.3 %, 9.6 %和 7.2 %,三环多环芳烃的含量最高;表层沉积物对多环芳烃的富集系数为532.7 ～ 1068.9,平均值为807.5,单组分菲的富集系数最高为122.7,最小的是苯并(a)芘为2.7;台州湾表层沉积物中的多环芳烃主要来源于燃煤污染,部分来源于石油烃类物质的直接污染. 相似文献
18.
Contents of heavy metals, polycyclic aromatic hydrocarbons （PA Hs）, dichlorodiphenyltrichloroethanes （DDTs） and hexachlorcy- clohexanes （HCHs） in surface sediments from mangrove areas of the Leizhou Peninsula were analyzed in July and November 2005. Risk assessment criteria applied by Long E R et al. （1995） and Long E D et al. （1995） （effects range low, ERL; effects range mean, ERM） of chemicals in sediments from the gulf or estuary were used to assess the potential ecological risks of heavy metals, PAHs, DDTs and HCHs to aquatic organisms in the studied area. The results indicated that the average contents of zinc, nickel, chromium, lead, copper, arsenic and mercury were （61.97 ± 55.87）, （59.99 ± 39.01 ）, （47.93 ± 28.37）, （26.64± 13.00） , （23.45 ± 41.96）, （9.32 ± 3.62）, （0.14 ± 0.18） mg/kg in dry weight in the sediment samples col- lected from five studied sites in the Leizhou Peninsula, respectively. Cadmium was not calculated due to its content being below the detection limit （ 〈 0.3 mg,/kg）. The average levels of Cr, Cu, Ni, Pb, Zn and Hg exceed their background values. The average contents of Ni were higher than ERM. The contents of PAHs in the sediments from the five studied sites were （79.78 ± 43.70） ng/g in dry weight, far lower than ERL（4 022 ng/g）. The contents of DDE, DDD and DDTs in the sediments from five studied sites were （2.60 ± 4.68）, （ 17.52 ± 27.25 ）, （27.78 ± 46.64） ng/g in dry weight respectively, clearly higher than ERL, and the average contents of DDT were （7.66 ± 15.93） ng/g in dry weight, much higher than ERM. HCHs could be detected in the sediments only from Gaoqiao sampling site, with the average contents （0.07 ± 0.08） ng/g in dry weight. 相似文献
19.
Deposit-feeding polychaetes constitute the dominant macrofauna in marine environments that tend to be depositional centers for organic matter and contaminants. Polychaetes are known to accumulate polycyclic aromatic hydrocarbons (PAHs) from both particulate and dissolved phases but less is known about the mechanisms underlying elimination of accumulated PAHs. An important pathway of elimination is through biotransformation which results in increased aqueous solubility of the otherwise hydrophobic PAHs. Biotransformation in marine polychaetes proceeds in a two phased process similar to those well studied in vertebrates, phase I enzymes belonging to the Cytochrome P450 (CYP) enzyme family, along with a few phase II enzymes have been identified in marine polychaetes. In this review we aim at highlighting advances in the mechanistic understanding of PAH biotransformation in marine polychaetes by including data obtained using analytical chemistry and molecular techniques. In marine polychaetes induction of CYP enzyme activity after exposure to PAHs and the mechanism behind this is currently not well established. Conflicting results regarding the inducibility of CYP enzymes from polychaetes have led to the suggestion that induction in polychaetes is mediated through a different mechanistic pathway, which is corroborated by the apparent lack of an AhR homologous in marine polychaetes. Also, none of the currently identified CYP genes from marine polychaetes are isoforms of those regulated by the AhR in vertebrates. Relatively few studies of phase II enzymes in marine polychaetes are currently available and most of these studies have not measured the activity of specific phase II enzymes and identified phase II metabolites but used an extraction technique only allowing determination of the overall amount of phase II metabolites. Studies in insects and various marine invertebrates suggest that in invertebrates, enzymes in the important phase II enzyme family, UDP-glucuronosyl transferases primarily use glucoside as co-substrate as opposed to the vertebrate cosubstrate glucuronic acid. Recent studies in marine polychaetes have however identified glucuronidation of PAHs indicating no mechanistic difference in co-substrate preference among UDP-glucuronosyl transferases between vertebrates and marine polychaetes but it might suggest a mechanistic difference between marine polychaetes and insects. 相似文献
20.
海洋沉积物的顺序萃取方法及其在冲绳海槽热液影响沉积物中的应用 总被引：1，自引：0，他引：1
不同沉积环境和沉积机制下进入海洋沉积物中的元素分别与不同介质结合,因此,将沉积物中不同结合形态元素相分离的顺序萃取方法是研究沉积物源和沉积环境的重要手段。以Tessier等建立的萃取流程为基础,针对深海沉积物标准物质GBW07315中Fe、Mn、Co、Cu、V元素,分析了方法的准确性和重复性。结果表明:各元素回收率基本介于94%～126%之间,平均值为106%。在重复性方面,除V元素在铁锰氧化物结合态中的相对标准偏差较高外,其余元素在铁锰氧化物结合态、有机结合态以及残渣态中的相对标准偏差均低于15%,而碳酸盐结合态和可交换态中元素的相对标准偏差较大,这与其样品中这些结合态的元素含量相对较低有关。因此,对于深海沉积物来讲,顺序萃取法具有较好的稳定性和可靠性,尤其是对其中铁锰氧化物结合态、有机结合态和残渣态的萃取效果令人满意。将该方法应用于冲绳海槽热液影响沉积物中,实现了热液源铁锰氧化沉积的有效萃取和分离。 相似文献