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1.
Diatom Skeletonema costatum Cleve is one of the main predominant phytoplankton species in the Changjiang Estuary in China. In order to provide some basic information for future assessment of the potential risk on phytoplankton communities in this estuary caused by polycyclic aromatic hydrocarbons(PAHs), this alga was selected as a representative to investigate the photoinduced toxicity of PAHs, in single and mixture. Four PAHs including three-ring phenanthrene and anthracene, four-ring fluoranthene and pyrene were tested in the laboratory. The single toxicity of each PAH on this microalga was compared with and without the simulated solar UV radiation. The results showed that this microalga was sensitive to PAH's photoinduced toxicity. Ratios of the 72 h median effect concentration obtained for fluorescent and UV light tests were about 8.4 for phenanthrene, 13.0 for anthracene, 6.5 for fluoranthene, and 5.7 for pyrene, indicating that UV light enhanced the PAH toxicity to this alga significantly. Under the fluorescent radiation (lacking UV), the dose-response curves based on chemical concentrations revealed that the order of toxic strength was fluoranthene greater than pyrene greater than anthracene greater than phenanthrene; while under the UV radiation (476 μW/cm2 for UVA, 6.5 μW/cm2 for UVB) it became fluoranthene approximately equaling anthracene greater than pyrene greater than phenanthrene, indicating that the UV light also changed its relative toxicity to this alga. The photoinduced toxicity of PAHs to the marine diatom S. costatum might be a synergistic effect of photosensitization reactions (e.g., generation of single-state oxygen) and photomodification (photooxidation and/or photolysis).The combined effects of six binary mixtures on the marine diatom S. costatum were investigated using the additive-index method. Four binary-mixtures (phenanthrene plus anthracene; phenanthrene plus pyrene; anthracene plus fluoranthene; anthracene plus pyrene) were found to be synergistic joint action mode, while two binary-mixtures (phenanthrene plus fluoranthene; fluoranthene plus pyrene) displayed antagonist, revealing a complex pattern of possible interactions. The combined action mode of PAHs might be related to various factors such as the mixture compounds, mixture ratios and test conditions, etc.  相似文献   

2.
夏季珠江口水体中多环芳烃的分布、组成及来源   总被引：2，自引：0，他引：2  
利用1999年7月对珠江口海域的调查资料,对该区表层海水中优控多环芳烃的分布、组成及来源进行了分析和讨论,结果表明:(1)夏季珠江口海域表层海水中14种溶解态多环芳烃[苊、芴、菲、蒽、荧蒽、芘、苯并(a)蒽、艹屈、苯并(b)荧蒽、苯并(k)荧蒽、苯并(a)芘、二苯并(a,h)蒽、苯并(g,h,i)艹北、茚并(1,2,3-cd)艹比]的质量浓度为63.8~171.7 ng/L,且沿着冲淡水流向呈降低趋势;(2)颗粒态中15种多环芳烃[萘、苊、芴、菲、蒽、荧蒽、芘、苯并(a)蒽、艹屈、苯并(b)荧蒽、苯并(k)荧蒽、苯并(a)芘、二苯并(a,h)蒽、苯并(g,h,i)艹北、茚并(1,2,3-cd)艹比]的质量浓度为60.7~186.7 ng/L,其分布与水体载沙量及悬浮颗粒物的性质、粒径有关,具有从河口内向外海降低的分布特征;(3)多环芳烃组成和特征参数比值的分析表明,珠江口海域高温裂解来源的多环芳烃在伶仃洋海区输入最多,且主要为人类活动中煤燃烧排放的,而在香港岛周围海区的输入则相对较少,且主要为油燃烧排放的;(4)与法国塞纳河及长江口等河口相比,珠江三角洲海域水体中存在高菲含量排放源。  相似文献   

3.
Little is known about the types and concentrations of polycyclic aromatic hydrocarbons (PAHs) existing in the deep-sea subsurface environment, which is believed to be cold, oligothrophic and of high static pressure. PAHs in the upper layers of the water column are unavoidably subjected to degradation while they are deposited to the sea floor and become embedded in the deep-sea sediment. In this report, a high concentration of PAHs was discovered in the sediment 2.7 m beneath the bottom surface at a water depth of 3962 m on the Mid-Atlantic Ridge (MAR). The total concentration of PAHs was 445 ng (g dry wt sediment)-1. Among the seven detected PAHs, the concentrations of phenanthrene (222 ng g-1) and fluorene (79 ng g-1) were relatively high. In addition, PAH-degrading bacteria were found within the sediments. As in a previously detected site on the MAR, in the PAH-enriched region of this site, a bacterium of the genus Cycloclasticus was found to be the predominant isolate detected by PCR-DGGE analysis. In addition, bacteria of the Halomonas, Marinobacter, Alcanivorax, Thalassospira and Maricaulis genera, were also included in the PAH-degrading community. In summary, a high concentration of PAHs was detected in the subsurface of the deep-sea sediment, and once again, the Cycloclasticus bacterium was confirmed to be a ubiquitous marine PAH degrader even in the subsurface marine environment. Considering the abundance of PAHs therein, biodegradation is thus thought to be inactive, probably because of the low temperature, limited oxygen and/or limited nutrients.  相似文献   

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   

5.
This study examined the concentrations of polycyclic aromatic hydrocarbons (PAHs) in surface sediments collected in July 2004 from eight stations in the Zhelin Bay, one of the most important bays for large-scale mariculture in Guangdong Province. Thirteen individual parent PAH compounds were identified using high performance liquid chromatography with UV detection. The overall average concentration of total PAHs was 477.0 ng/g, ranging from 146.1 to 928.8 ng/g. Low molecular mass PAHs with two to three rings (e.g., acenaphthene) were dominant in each sample. The PAH concentration varied among sampling stations, with the highest concentration observed at bay outlets and the lowest found at stations outside the bay. Ratios of low to high molecular mass PAHs and fluoranthene to pyrene were used to determine the origin of PAHs, and results indicated mainly petroleum-derived contamination. Compared with other bays and harbors around the world, the total concentrations of PAHs in surface sediments at the Zhelin Bay are moderate, but this does not exclude the possibility of potential impact on human consumers because some strong carcinogenic PAHs with high molecular mass were found at the station with a nearby caged-fish and oyster farm. Long-term monitoring of PAH contamination in the Zhelin Bay is recommended to reduce the potential toxicological effects on aquatic organisms and humans.  相似文献   

6.
海洋微生物对多环芳烃的降解   总被引：15，自引：1，他引：15  
从海域沉积物中富集分离出以芘作为唯一碳源和能源的海洋微生物，以ST4富集培养的混合微生物作为研究对象；该海洋混合菌株能利用菲（Phe）、芘（Pyr)、荧蒽（Fla)等多种多环芳烃；在不同浓度的芘的降解中，当芘的浓度为50mg/dm^3时，其生长水平和降解速率最高；当芘的浓度为200mg/dm^3时，其生长受到抑制，芘几乎不能被降解。外加营养盐酵母浸出液和葡萄糖促进降解微生物的生长，提高降解速率。研究表明了海洋微生物在多环芳烃污染环境的生物修复应用前景。  相似文献   

7.
The relative potency of polycyclic aromatic compounds as aryl hydrocarbon receptor (AhR) agonists in fish was determined using data on CYP1A induction or AhR binding for 74 polycyclic aromatic hydrocarbons (PAHs) and heterocycles in teleost, avian, or mammalian systems from 18 published papers. Each PAH was assigned a fish potency factor relative to the potency of 2,3,7,8-tetrachlorodibenzo-p-dioxin as an AhR agonist. Two and three ring unsubstituted PAHs were generally inactive in fish, avian, and mammalian systems. Benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene were consistently the most potent PAHs, with fish potency factors of 0.001-0.002. Common structural features associated with higher potency PAHs included 4-6 rings containing fluoranthene or phenanthrene structures with an exposed bay region. These results show that PAHs can have similar potency as many dioxin-like PCBs, and AhR mediated toxicity should be considered in assessing the risks of PAHs in fish.  相似文献   

8.
南大西洋沉积物中多环芳香化合物的组成特征研究   总被引：1，自引：0，他引：1  
10 samples of sediments obtained from the South Mid-Atlantic Ridge were measured for the abundances and distributions of polycyclic aromatic compounds(PAHs). The total concentrations of PAHs(∑PAHs) ranged from 2.768 to 9.826 μg/g dry sediment. The ∑PAHs was higher in sample 22V-TVG10 and sample 26V-TVG05 which were close to hydrothermal fields, with the lowest value in sample 22V-TVG14 which was farthest from hydrothermal fields, suggesting a probable hydrothermal origin of ∑PAHs of samples. Approximately nine kinds of PAHs were identified, and low molecular mass tricyclic and tetracyclic aromatic compounds were predominant in the samples. The concentrations of fluoranthene which were typical as hydrothermal alteration compounds were the highest among PAHs with dry weight between 0.913–3.157 μg/g. The phenanthrene homologue was most abundant in the samples, and the ratios between parent phenanthrene and methylphenanthrene which probably reflected the degree of hydrothermal alteration ranged from 0.097 to 1.602. The sample 22V-TVG10 possessing a maximum ratio value showed the intense influence of the hydrothermal alteration on this sample, which might further imply that PAHs in sediments were mainly derived from the hydrothermal alteration.  相似文献   

9.
Stress proteins (heat shock proteins, hsps) form part of the cellular protein repair system, and are induced by a wide variety of Stressors. To determine their suitability as tools for assessing sublethal sediment toxicity, we measured levels of members of the stress protein families hsp60 and hsp70 in benthic estuarine amphipods (Ampelisca abdita) exposed to sediments from 23 different sampling sites in San Francisco Bay for 10 d. Concentrations of sediment-associated xenobiotics were determined. Per cent survival was recorded and surviving animals were analysed for stress proteins using western blotting techniques. An inverse correlation (r2 = 0.44) was seen between amphipod survival and hsp64 levels, and hsp64 levels were positively correlated with concentrations of total polycyclic aromatic hydrocarbons (PAHs) (r2 = 0.5). Principal component analysis revealed that amphipod mortality was linked to a combination of several PAHs (phenanthrene, fluoranthene, pyrene, benzo(a)pyrene) and di-n-butylphthalate at southern San Francisco Bay sites. At northern San Francisco Bay sites, negative correlations were found between hsp64 levels and organotin compounds (MBT, DBT, TBT), and between hsp71 levels and the PAHs, benzo (b,k)fluoranthene and benzo(G,H,I)perylene, suggesting an inhibitory effect of these compounds on stress protein expression.  相似文献   

10.
Polycyclic aromatic hydrocarbon (PAH) bioaccumulation by the polychaete worm Streblospio benedicti (Webster) was measured under exposure to PAH-contaminated sediments in the field and for 28 d in the laboratory. Streblospio benedicti collected from field sediments contaminated at 2.94, 1.07, and l.52 μg g−1 fluoranthene (FLU), benz[a]anthracene (BAA), and benzo[a]pyrene (BAP), bioaccumulated those PAHs at 1.53, 0.215, and 0.332 μg g−1, while worms isolated from less contaminated field sediments (0.399, 0.228, 0.288 μg g−1 FLU, BAA, and BAP) had FLU, BAA, and BAP body burdens of 0.543, 0.236, and 0.083 μg g−1. Worms incubated for 28 d in PAH-spiked sediments (1.52, 0.991, 0.504 μg g−1 FLU, BAA, and BAP) bioaccumulated those PAHs at 0.382, 0.966, and 0.602 μg g−1, respectively. Data normalization to organism lipid and sediment organic carbon (biota-sediment accumulation factors [BSAFs] strongly suggest that Streblospio PAH bioaccumulation was directly related to percent sediment organic carbon, but BSAFs were substantially lower than predicted by equilibrium partitioning theory. BSAFs decreased with increasing PAH log Kow, in worms collected from field sediments, but in spiked sediments BSAFs increased with increasing PAH hydrophobicity. This disparity may have been caused by insufficient spiked-sediment equilibration time (1.5h) in the case of the laboratory test sediments.  相似文献   

11.
The scope of this work was to evaluate the levels of polycyclic aromatic hydrocarbons (PAHs) and their possible sources in two shallow sediment cores from an estuarine area located in the south region of Brazil, the Guaratuba Bay. The estuary is encompassed by an Environmental Protection Area (EPA) of 1306 km2, which is still considered to be pristine, despite recent urban growth. To assess levels of 14 selected PAHs in the sediments, among those listed as “priority pollutants” by the US Environmental Protection Agency, the cores were divided in several sections, followed by extraction, clean-up, fractionation and subsequent analysis using HPLC coupled to a fluorescence detector. Among the PAHs detected, phenanthrene and fluoranthene showed the highest concentrations. PAHs with more than four rings were usually present in low concentrations or were undetectable. To assist in the identification of possible sources, the ratios An/(An + Phe) and Flt/(Flt + Py) (anthracene to anthracene plus phenanthrene and fluoranthene to fluoranthene plus pyrene) and a PCA model were also used. Total concentrations of PAHs ranged between 1.5 and 3130 ng/g (mean 495) dry weight for the core collected in the inner part of the estuary, and between 78.5 and 3270 ng/g (mean 899) dry weight for the other core, collected in the outer part. Compared to values found in other studies in coastal zones along South American eastern margin, this area can be considered to range from low polluted to moderately polluted. From the data, it was also possible to conclude that there is predominance of petroleum sources, and essentially close to the more urbanised areas. Combustion sources have only minor contribution and are episodic, when compared to the latter.  相似文献   

12.
Polycyclic aromatic hydrocarbons (PAHs) were identified and measured in surface seawater and in the tissues (gills and mantle) of indigenous black mussels, Mytilus galloprovincialis, collected from three coastal sites of Saronikos Gulf (Greece), a gulf that exhibits high levels of pollution. The total PAHs measured by spectrofluorometry in the surface seawater were found in the range of 425–459 ng L−1 at the most polluted sites 1 and 2 (Elefsis Bay–Salamis Island) and in the range of 103–124 ng L−1 at site 3 (Aegina Island). PAHs' sources in seawater were identified by application of specific PAH ratios, such as phenanthrene/anthracene and fluoranthene/pyrene. Levels of PAHs in soft tissues (gills and mantle) of indigenous mussels were much higher than those reported for seawater. Total PAH concentrations in mantle tissues were in the range of 1300–1800 ng g−1 dry weight (dw) tissue at sites 1 and 2 and approximately 380 ng g−1 dw at site 3. In gill tissues total PAH concentrations were in the range of 1480–2400 ng g−1 dw at sites 1 and 2 and approximately 430 ng g−1 dw at site 3. PAHs composition was dominated by two-, three- and four-ring compounds in seawater, where 17 different PAH compounds were identified and measured in mussel tissues. Mussels can be used as sentinel organisms to monitoring PAHs' contamination, since they concentrate PAHs from the surrounding water media and therefore making the chemical analysis simpler and less prone to error than that for water. In surface seawater possible weathering and photodegradation due to hot climates contribute to reduced PAHs concentrations.  相似文献   

13.
The effect of sediment resuspension on the mineralization of phenanthrene was examined in microcosms and sediment slurries. In computer-controlled, flow-through microcosms, 14C-phenanthrene-amended sediments were resuspended into overlying oxic water at frequencies of 12, 4, 1, 0.25 and 0 d(-1). In slurry bottle experiments 14C-phenanthrene-amended sediments were continuously resuspended under oxic (excess air headspace) and anoxic (N2 headspace) conditions and mineralization was measured at periods from 2 h to 7 days. Our main findings were: (1) mineralization rate constants from the microcosms ranged from 0.001 to 0.01 d(-1) and increased with frequency of resuspension, (2) these rates fell between those measured in oxic and anoxic slurries and were predicted within a factor of 2.5 by a model in which mineralization depended on the degree of oxygen exposure, and (3) the phenanthrene-degrading bacterial community was more active in resuspended sediments incubated in the microcosms than in sediments which were not resuspended, or which were stored under refrigeration. We conclude from these experiments that the effects of sediment resuspension on phenanthrene degradation are consistent with a primary role of average oxygen exposure, and also an alteration in the PAH-degrading activity of microbial populations.  相似文献   

14.
Benthic amphipod,Grandidierella japonica widely inhabits the Korean coastal waters and is developed as a standard test species for sediment toxicity tests. We exposedG . japonica to various pollutants including 4 kinds of inorganic metals (Ag, Cd, Cu and Hg), tributyltin [TBT], ammonia and 7 polycyclic aromatic hydrocarbon (PAH) compounds (acenaphthene, chrysene, fluoranthene, fluorene, naphthalene, phenanthrene and pyrene) to estimate the no observed effect concentration (NOEC) and the median lethal concentration (LC50) of each pollutant during the 96-hour acute exposure. Among all tested pollutants, TBT was most toxic toG. japonica, and Hg was most toxic among inorganic metals. The toxicity of pyrene toG. japonica was greatest among PAH compounds, followed by fluoranthene, phenanathrene, acenaphthene, fluorene and naphthalene. The toxicity of PAH compounds was closely related to their physico-chemical characteristics such as Kow and water solubility.G. japonica responded adequately to pollutant concentrations and exposure durations, and the sensitivity ofG. japonica to various inorganic and organic pollutants was generally comparable to other amphipods used as standard test species in ecotoxicological studies, indicating this species can be applied in the assessment of environments polluted by various harmful substances.  相似文献   

15.
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   

16.
The possibility of using the pyrene metabolite 1-hydroxypyrene as a biomarker of polycyclic aromatic hydrocarbons (PAHs) exposure was investigated by exposure of the marine polychaete Nereis diversicolor to several PAHs in the laboratory. Animals were exposed to pyrene alone and to five different PAHs – phenanthrene, anthracene, pyrene, benzo[a]pyrene and benzo[k]flouranthene. After five days of exposure the concentrations of parent PAHs and 1-hydroxypyrene were identified using three different analytical methods, high-performance liquid chromatography with fluorescence detection (HPLC/F), synchronous fluorescence spectroscopy (SFS) and gas chromatography with mass spectrometric detection (GC/MS). The SFS measurements of 1-hydroxypyrene were validated by the more sensitive method HPLC/F. The positive correlation between total PAHs and 1-hydroxypyrene concentrations in the polychaete tissues observed in experiments, suggests the feasibility of 1-hydroxypyrene as a suitable biomarker for total PAH exposure assessment. Furthermore, the possibility of employment of the simple and rapid SFS method instead of HPLC/F for biomarker analysis has been confirmed by the positive and significant correlation between results achieved by these two analytical methods.  相似文献   

17.
本文在现场情况下，研究了自然条件下受污染海岸带沉积物中的7种多环芳烃（Polynuclear Aromatic Hydrocarbons，简称PAHs）的解吸动力学行为。结果表明，7种PAHs）的解吸动力学行为。结果表明，7种PAHs的解吸动力学行为可以用二元模型模拟。文中并将所得数据与文献报道的数据进行了比较。  相似文献   

18.
Sebastiscus marmoratus larvae were exposed to waterborne polycyclic aromatic hydrocarbons (PAHs) containing 3-5 rings, benzo[a]pyrene (BaP), pyrene (Py) or phenanthrene (Phe), respectively at 0.01, 0.1 and 1 μg L?1. Cumulative mortality, frequency of dorsal curvature and rate of pericardial and yolk sac edema in larvae treated for 8 days were significantly increased in a dose-dependent manner. All three PAHs resulted in reduction of the lower jaw, and the extent of reduction increased with increasing concentrations of the PAHs. Na+/K+-ATPase and Ca2+-ATPase activity in larvae exposed to the three PAHs were all significantly inhibited in a dose-dependent manner. Analysis using the Pearson correlation coefficient indicated a significant correlation between the rate of the dorsal curvature and edema and the inhibition of Na+/K+-ATPase and Ca2+-ATPase activity, suggesting that the developmental defects caused by PAHs were related to their inhibition of Na+/K+-ATPase and Ca2+-ATPase activity.  相似文献   

19.
The purpose of this study was to investigate the accumulation behavior of two typical PAHs,phenanthrene(PHE) and fluoranthene(FLA),uptaken by the mangrove Kandelia candel in various treated sandy soils.The experiment lasted for three months.Soil and plant samples were collected after 3,6,9 and 13 weeks of the incubation and the levels of PAHs were analyzed using a GC/MS(HP6890-5975B).The results showed that the root accumulations of PHE and FLA were elevated with the increase of the PAH concentrations in the soil.With prolonged exposure time,PHE and FLA concentrations of the roots increased significantly in comparison with the control.PHE and FLA concentrations of root after 13 weeks of treatment ranged from 0.28 to 4.36 μg·g-1 and 0.79 to 35.76 μg·g-1,respectively.The calculated mean values of the root concentration factors were 0.58 for PHE and 0.71 for FLA.This indicated that root accumulation of FLA was greater than PHE,which would result from the higher octanol-water partition coefficient(Kow) of FLA.These results underline the ability of mangroves to remove PAHs from contaminated marine substrates and hence their potential use in bioremediation and the removal of PAHs from the marine food chain.  相似文献   

20.
Experimental exposure tanks were set up containing 'clean' marine sediment spiked with set doses of polyaromatic hydrocarbons (PAH), or polychlorinated biphenyls (PCB), or both. Reference tanks contained only 'clean' sediment. Female dab Limanda limanda L., exposed to these sediments for 7 days showed no differences in serum total protein concentration, serum lysozyme activity or body growth. Their kidney leucocytes were assayed for extracellular production of reactive oxygen species of the phagocytic respiratory burst. No significant differences in superoxide anion (O2-) production were found between fish exposed to the 'spiked' sediments and those on the 'clean' reference sediment. The production of hydrogen peroxide (H2O2) was, however, reduced in the fish held on the PAH and PAH/PCB spiked sediments. H2O2 levels for fish exposed to PCBs alone, did not differ significantly from those of control fish. Our results suggest that the decrease in H2O2 production was due to exposure to PAHs, rather than to PCBs.  相似文献   

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