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81.
Variation of polycyclic aromatic hydrocarbons (PAHs) levels was assessed in Tapes philippinarum from the Lagoon of Venice. Clams were transplanted from a polluted area next to Porto Marghera to two rearing areas of the Southern Lagoon. Analyses of PAHs were made in sediments and clams by GC/MS at first sampling and after 30, 60 and 180 days. Principal component analysis was performed to elucidate bioaccumulation and depuration pattern and input sources. Biota-Sediment-Accumulation-Factor (BSAF) was applied to evaluate the PAHs input sources from sediment. Condition index was calculated to compare the seasonal variation of clam tissue to PAHs levels. To propose results not affected by seasonal changes in flesh weight of clams, the approach based on the calculation of PAHs/SW index was applied. From the results, it was concluded that PAHs/SW index is more recommendable to asses temporal variation of PAHs levels in Manila clams.  相似文献   
82.
我国湖泊沉积物多环芳烃的分布特征及来源分析   总被引:1,自引:0,他引:1  
湖泊沉积物不但可以反映流域多环芳烃(PAHs)的空间分布特征,更能忠实的记录PAHs排放历史.本文收集了我国湖泊沉积物有关PAHs已有的文献报道,并与部分发达国家和地区(美国、欧洲、日本等)的湖泊做对比,系统地综述了我国湖泊沉积物多环芳烃的空间分布、沉积记录及来源.通过对收集数据分析表明,我国湖泊表层沉积物中∑PAHs含量为3.2~ 5260ng/g(dw),平均值为753.1 ng/g (dw)(n=495).主成分分析及多元回归分析结果表明:我国湖泊表层沉积物PAHs主要来源及其贡献量分别为机动车尾气排放占42.7%、煤炭燃烧占30.1%以及石油泄漏占27.2%.我国湖泊钻孔沉积记录PAHs从下向上总体表现出由低到高的变化特征,基本反映了我国经济发展历史.我国PAHs排放历史与发达国家有着明显不同,PAHs排放峰值一般出现在20世纪90年代以后,明显晚于发达国家的50 ~ 80年代.同时,湖泊沉积物记录的PAHs来源有所改变,煤炭资源是我国部分湖泊沉积历史中PAHs的主要来源,随着机动车数量的增加,机动车尾气排放也成为目前我国湖泊沉积物的主要污染源之一.  相似文献   
83.
通过对渤海湾中部海域19个站位表层沉积物样品中检测出的13种优控多环芳烃(EPAs)进行同分异构体、甲基菲、GC—MS定量等分析,探讨了研究区沉积物中多环芳烃分布特征、输入来源和污染水平,结果表明,研究区表层沉积物中多环芳烃总含量为2.1~374.8ng/g,平均值为33.1ng/g,多环芳烃总含量呈现出由近岸区向深海区递减的趋势,除最高值BG-60站位外,研究区与其他地区相比污染水平为中—低;化合物组成上以3~4环为主,5~6环次之,从多环芳烃组成以及异构体和甲基菲比值分析表明,研究区沉积物中PAHs以燃烧来源为主,石油类产品和石油化工燃料燃烧贡献最大,煤、木材燃烧贡献次之;高含量的菲和4个高成熟度异常点证实石油烃PAHs污染客观存在。  相似文献   
84.
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   
85.
Reports of the occurrence and accumulation patterns of polycyclic aromatic hydrocarbons (PAHs) and synthetic musk compounds (SMCs) in marine mammals are scarce. In this study, the concentrations and accumulation profiles of PAHs and SMCs were determined in blubber from finless porpoises in Korean coastal waters. Total concentrations of PAHs and SMCs ranged from 6.0 to 432 (mean: 160) ng/g lipid weight and from 17 to 144 (mean: 52) ng/g lipid weight, respectively. Residue levels of PAHs were lower than those reported from other studies, while residue levels of SMCs were relatively higher than those reported in other studies. Naphthalene was the most abundant PAH and HHCB was the dominant SMC observed in finless porpoises. The concentrations of PAHs and SMCs were not correlated with each other, but were significantly correlated within the same chemical groups. No correlations were found between body size and residue levels of PAHs and SMCs.  相似文献   
86.
Recent occurrence, distribution and mass inventories of 16 priority polycyclic aromatic hydrocarbons (PAHs) proposed by USEPA in the south Bohai Sea (BS) were studied based on the analytical data of 71 surface sediment samples. The concentrations of 16 PAHs varied from 37 to 537 ng g−1 (dry weight). A clear difference was observed between the coastal Bohai Bay (CBB) and its adjacent BS (ABS) in the distribution and compositions of PAHs. The petrogenic source of phenanthrene in CBB was attributable to the industrial wastewater, fugitive fuel leakages from ships and offshore oil production. Four to six ring PAHs were predominantly from the coal and wood combustions in the whole area. The estimated PAH input to the south BS (43,000 km2, 56% of BS in area) was 36.6 ton yr−1, indicating that the study area was one of the important reservoirs of PAHs in world.  相似文献   
87.
Segara Anakan, a mangrove-fringed coastal lagoon in Indonesia, has a high diversity of macrobenthic invertebrates and is increasingly affected by human activities. We found >50 organic contaminants in water, sediment and macrobenthic invertebrates from the lagoon most of which were polycyclic aromatic compounds (PACs). Composition of PACs pointed to petrogenic contamination in the eastern lagoon. PACs mainly consisted of alkylated PAHs, which are more abundant in crude oil than parent PAHs. Highest total PAC concentration in sediment was above reported toxicity thresholds for aquatic invertebrates. Other identified compounds derived from municipal sewage and also included novel contaminants like triphenylphosphine oxide. Numbers of stored contaminants varied between species which is probably related to differences in microhabitat and feeding mode. Most contaminants were detected in Telescopium telescopium and Polymesoda erosa. Our findings suggest that more attention should be paid to the risk potential of alkylated PAHs, which has hardly been addressed previously.  相似文献   
88.
After the Hebei Spirit oil spill incident (7th December, 2007) in the west coast of Korea, contamination of biliary PAH metabolite and hepatic biomarkers in a pelagic and a benthic fish was monitored for 1 year. Concentrations of 16 PAHs and alkylated PAHs in fish muscle were highest (22.0 ng/g d.w. for 16 PAHs and 284 ng/g d.w. for alkylated PAHs) at 5 days after the spill and then decreased rapidly to background levels at 11 months after the spill. Fish from the oiled site had elevated biliary PAH metabolite concentrations immediately after the spill; these declined steadily in both species, but were still above reference site concentrations 2 months after the spill. Oiled-site fish showed hepatic CYP 1A induction whose trend closely followed those of biliary PAH metabolite concentrations, implying continuous exposure to PAHs. Brain acetylcholinesterase activity was not related to oil exposure.  相似文献   
89.
采用高效液相色谱法对沈阳市地表土壤中的多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)进行了定量分析,研究了沈阳市地表土壤中PAHs在不同功能区的含量及分布特征。结果表明:从土壤PAHs总量来看,居民区最低,其次是商业区,交通干道、文教区和公园排在商业区之后,工业区的PAHs总量最多;从PAHs的空间差异来看,靠近工业区以及机动车车流量较大的地区PAHs含量较高,靠近文教区和居住区的地区PAHs含量较低;从PAHs种类来看,所有功能区样品中PAHs的组分分布状况较为一致,以四环PAHs含量最多,其次是五环PAHs和三环PAHs;参考美国EPA沉积物PAHs质量标准和治理标准,沈阳市内五区PAHs总量超过质量标准的功能区有工业区、交通干道(4个采样点,占比36.3%)、文教区(3个采样点,占比75%)和公园区(4个采样点,占比40%),超过治理标准的功能区有工业区,公园区(1个采样点,占比10%),文教区(1个采样点,25%)。  相似文献   
90.
The influence of each of four organic pollutants selected from among those commonly found in coastal areas, 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (DDE), monobutyltin (MBT), Triton X-100 and polycyclic aromatic hydrocarbons (PAHs), on Cu accumulation by Halimione portulacoides was investigated. Experiments were carried out in a laboratory setting, either in hydroponics (sediment elutriate) or in a salt marsh sediment (Cávado River, NW Portugal) soaked in elutriate. Groups of H. portulacoides were exposed to media for 6 days spiked with 10 mg/L Cu(II) and with one of the selected pollutants, at an environmentally realistic concentration. DDE and MBT did not cause any major change on Cu accumulation by H. portulacoides, whereas PAHs slightly increased accumulation only in hydroponics i.e. in the absence of sediment. On the other hand, the non-ionic surfactant Triton X-100 markedly favoured Cu accumulation on plant roots both in the presence and absence of sediment. The addition of DDE, MBT and Triton X-100 also favoured Cu solubility from sediments. Therefore, the simultaneous presence of pollutants from different nature (inorganic and organic) in the estuarine environment may result in a composition of water column, pore water, sediment or biota different of that expected considering the effect of each individual pollutant.  相似文献   
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