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21.
Changes in the levels and spatial distribution of PAHs as a consequence of the Oder flood in the summer of 1997 were investigated in post‐flood sediments from the Oder River and the Oder Lagoon. The aim of this study was to identify sources of the PAH pollution and in particular investigate polluted sites (“hot spots”) in the most highly suspected locations of the drainage area. Molecular indices based on isomeric PAH ratios and the ratio of the parent PAHs to methylated PAHs were used to distinguish between the pollution sources. Elevated levels of PAHs were discovered in the post‐flood sediments of the Oder River in comparison to the average regional values. Elevated concentrations of PAHs were also found in fluffy layer samples taken from the Oder Lagoon and the Pomeranian Bight in late August. The highest concentrations of PAHs were observed near power plants or roads with heavy traffic. Most of the contamination originates from high temperature pyrogenic sources with some slight overlays of petrogenic sources. These increased concentrations of pyrogenic origin may be attributable to flooding of municipal and industrial waste disposal areas in the Oder River drainage.  相似文献   
22.
The solubilization and degradation of polycyclic aromatic hydrocarbons (PAHs) in soil was amending by many microorganisms. One of these microorganisms is Bacteria, which were isolated from different contaminated areas at Kafer El Zyat City, Gharbia governorate, Egypt. Wastes samples were collected and bacterial isolation was carried out using enriched media technique. More than 78 isolates were obtained and the degradation capability was examined for all of them. Fingerprinting was carried out for all the isolates using REP-PCR and the obtained results grouped them into 10 groups. Two bacterial strains from the isolated bacteria were showed high degradation talent and specificity for the type of the polyaromatic hydrocarbons (naphthalene or phenol). Pseudomonas putida (DQ399838) and Flavobacterium sp. (DQ398100) were identified and their degradation capacity was examined using real time method. Strain P. putida showed degradation rate for naphthalene reached to 50% after 20 hours from inoculation. However, Flavobacterium sp. reached 50% rate of degradation after 17 hours from inoculation time. Whenever, the soil degradation rate can be enhanced by adding these adapted bacteria to the soil and amendment of these bacteria which will help in bioremediation technology.  相似文献   
23.
To reduce rehabilitation time and improve survival, a practical, objective test is needed to determine if marine birds are contaminated with oil before they enter captivity. The RaPID Assays and EnviroGard immunoassays for detection of polycyclic aromatic hydrocarbons (PAHs) in soil were evaluated for their ability to detect petroleum on feather samples from 30 intermediate fuel oil contaminated and 30 uncontaminated common murres (Uria aalge). Sensitivity, specificity, positive and negative predictive value, precision, and time required to run each assay were determined. The RaPID Assays was 96.7% sensitive and specific, while the EnviroGard assay was 93.3% sensitive, and 90.0% specific. Sensitivity decreased at higher dilutions for both assays. Intra-replicate variation was less than 20%. Our evaluation showed that these immunoassays are rapid and cost-effective methods for detecting oil-contamination on the plumage of seabirds, with the EnviroGard assay being more practical in most oil spill response situations due to ease of use and rapidity of results.  相似文献   
24.
原煤尾气和煤渣中多环芳烃相关性测定   总被引:2,自引:0,他引:2  
张丽珠  刘永庆 《岩矿测试》1996,15(4):268-273
对原煤、尾气和煤渣中多环芳烃进行了相关性测试。在模拟工业锅炉代表性燃烧条件下将烟煤和无烟煤样品在管式炉中燃烧,分别采用GCMS和HPLC法对原煤、尾气和煤渣中的多环芳烃种类和含量进行了定性和定量测定。通过在特定条件下某一煤种中多环芳烃种类、含量在燃前、燃后变化的相关性,探索煤中多环芳烃在燃烧过程中的衍变规律  相似文献   
25.
多环芳烃生物恢复技术的研究进展   总被引:2,自引:0,他引:2  
多环芳烃是一大类广泛存在于环境中的有机污染物,本文介绍了多环芳烃生物恢复的三种不同方法:就地耕作法,场外耕作法和塞流式污泥生物反应器,并对其研究现状和最新研究成果进行了归纳,总结和探讨。  相似文献   
26.
The distribution and fate of polycyclic aromatic hydrocarbons (PAHs) were investigated in surface sediments (0...2 cm) and fluffy layer material of the internal and external coastal waters of the Odra river estuary (north-eastern Germany). The area includes the Odra Lagoon (Oderhaff), the Greifswalder Bodden, the Pomeranian Bight, and the Arkona Basin. Elevated concentrations were observed in the surface sediments of the internal coastal waters with highest concentrations in the Odra Lagoon. This indicates a significant contribution of river discharge to the contamination of sediments with PAHs. During the exceptional Odra flood in the summer of 1997 significantly higher concentrations of PAHs were found in the fluffy layer material of the Odra Estuary. The distribution of the individual PAH compounds varies widely depending on their structure and molecular weight. A concentration gradient of the lower molecular weight PAHs was found from the Odra Lagoon to the open sea areas. The concentrations decreased rapidly from the Oder Haff to the Arkona Basin. These results were found in both sediments and fluffy layer material. This is attributed to the degradation of the lower molecular weight PAHs during transport from the urban regions to the sedimentation basins. A decrease of this magnitude was not found for the higher molecular weight PAHs (i.e. benzo(a)pyrene) due to their higher persistence. An enrichment of these compounds was measured in the Arkona Basin.  相似文献   
27.
A study on the bulk distributions and molecular structures of n-alkanes and polycyclic aromatic hydrocarbons (PAH) in organic matter of the sediments from the Bay of Bengal and the Eastern and Central Indian Basins was undertaken. The former two regions represent areas characterised by “normal” sedimentation while the third one mainly represents a region of “active tectonism”. Content of the hydrocarbons in the sediments of “normal” sedimentation ranges between 4.6 and 10.5 μg/g and aromatic hydrocarbons ranges between 0 and 0.38 μg/g. n-Alkanes in the sediments of the northern deep part of the Bay of Bengal consist mostly of long-chain structures (total C25–C33 up to 70%) with a high carbon preference index (CPI=3.01–3.43), indicating a large contribution of organic matter from terrigenous sources. The sediments from the Eastern Indian Basin have n-alkane distributions in which the long-chain components did not exceed 52.5% and the CPI was 1.7–1.90, indicating that the hydrocarbons are mostly derived from marine sources. Sharp increases of hydrocarbons are found in the vicinity of the tectonically active region of the Central Indian Basin, particularly in the sediments collected from the fracture zone. The total concentration of hydrocarbons increase to 170 μg/g and the aromatic hydrocarbons fraction to 156.3 μg/g. The proportion of short-chain n-alkanes increases up to 70%, CPI decreases to 0.76–1.12, and high concentrations of n-C16 (16–40%) occur, all of which are absent in the other samples. The molecular content of PAH includes the unsubstituted individual structures: biphenyl, fluorene, pyrene, perylene, benzo(ghi)perylene, and the groups of homologues of naphthalene, benzofluorene, phenanthrene and chrysene. The association of the PAH and composition of paraffin hydrocarbons in the surficial sediments of deformation zone indicate that these are the resultant products of hydrothermal processes. It is, therefore, suggested that the association and composition of the hydrocarbons in sediments can be utilised as a paleoceanographic parameter to decipher the history of tectonism of an area.  相似文献   
28.
Polycyclic aromatic hydrocarbons (PAH) were measured in sediment cores from 13 locations in South-Western Barents Sea as part of a detailed study of the Norwegian seabed under the MAREANO program. The generally low PAH levels found, an average around 200 ng g−1 dry weight for sum PAH, indicate low inputs of petroleum hydrocarbons to the marine environment in the area. Differences in PAH composition and various PAH ratios indicate a natural, mostly petrogenic origin of PAH in sediments from the open sea locations, while the fjord locations show higher pyrogenic PAH contents with an increase towards upper sediment layers, indicating low inputs from human activities. Petrogenic PAH levels increase in deeper sediments at open sea locations, also when normalised to total organic carbon (TOC) contents, suggesting natural leakages of oil-related hydrocarbons in the area.  相似文献   
29.
王丽平  郑丙辉  孟伟 《海洋通报》2007,26(4):111-115
在实验室条件下研究了多环芳烃荧蒽和铜对三角褐指藻的单一和联合毒性。结果表明:在本实验所测试的浓度范围内,荧蒽(0~0.315μg/mL)和铜(0~1.262μg/mL)分别对该藻的生长产生了一定的影响,且都呈现较好的剂量-效应关系;其中当荧蒽浓度升高至0.079μg/mL或铜离子浓度升至0.317μg/mL时,开始明显抑制藻种群的增殖。经回归分析求得荧蒽和铜对三角褐指藻的72hEC50分别为(0.103±0.009)μg/mL和(0.531±0.037)μg/mL。在联合毒性实验中,定义0.5×EC50(荧蒽) 0.5×EC50(铜)=1个毒性单位(TU)。荧蒽和铜混合后,对三角褐指藻的72hEC50为(1.093±0.085)TU,其联合毒性效应方式表现为拮抗作用。  相似文献   
30.
A variety of sources of organic contaminants to the Great Barrier Reef lagoon and near-shore environment exist including boating activity, agriculture and urban run-off. Cytochrome P-450 1A activity as measured by ethoxy-resorufin O-deethylase (EROD) activity has been widely used as an indicator of the exposure of fish to organic contaminants such as polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAH) and some organochlorine pesticides. This study demonstrates the successful application of EROD measurements in a common Australian tropical estuarine fish species, Acanthopagrus berda (Pikey Bream), to identify areas under potential stress from organic contaminants. Fish were captured from four creeks draining agricultural land, a creek draining urban land and two creeks with less disturbed catchments. Significant induction of cytochrome P450-1A was observed in fish captured from Ross Creek (urban catchment, 7.4-fold) and Cromarty Creek (agricultural catchment, 6.4-fold). Increased activity was also observed in fish captured from other creeks draining agricultural land (Plantation Creek, Victoria Creek, Seymour River, 1.9–2.6-fold) as compared to those captured from creeks in undisturbed catchments (Baldy Creek, Fisher Creek, 67–114 pmol/min/mg protein).  相似文献   
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