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1.
《Marine pollution bulletin》2014,88(1-2):338-344
The concentrations of 22 polyaromatic hydrocarbons (PAH) in Posidonia oceanica seagrass, sediments, and seawater from the Alexandroupolis Gulf in the Aegean Sea, were investigated from 2007 to 2011. Temporal trends of total PAH contents in P. oceanica and sediments were similar. PAH levels in seawater, sediments, and seagrasses generally decreased with increasing distance from Alexandroupolis Port. Leaves and sheaths of P. oceanica had higher PAH levels than roots and rhizomes. P. oceanica accumulates PAHs and has good potential as a bioindicator of spatiotemporal pollution trends. PAH concentrations were also examined using in situ passive seawater sampling and were compared to results of passive sampling in the laboratory using local sediments and seawater. Levels of high molecular weight PAHs assessed using passive samplers confirmed the decreasing gradient of pollution away from Alexandroupolis Port. Passive sampling also proved useful for investigating sources of PAHs in P. oceanica meadows.  相似文献   

2.
This study measured concentrations of polycyclic aromatic hydrocarbons (PAHs) in surface sediments in the East China Sea (ECS) to investigate possible sources and fate of PAHs. Total concentration of PAHs in the sediments of the ECS ranged from 22 to 244 ng g(-1), with the highest levels in the coastal area and outer shelf. The observed PAH results showed elevated levels in both inner and outer shelf areas, a finding that is different from predictions by an ocean circulation model, suggesting that terrestrial sources are important for PAH contaminations in the ECS, while sediment resuspension, tidal changes and lateral transport may be important in affecting the distribution of PAHs in the outer shelf. The distribution of PAHs in the surface sediments of the ECS is similar to the distribution of carbonaceous materials (e.g., particulate organic carbon and black carbon), suggesting that carbonaceous materials may strongly affect the distribution of PAHs.  相似文献   

3.
Aliphatic and aromatic hydrocarbons in coastal Caspian Sea sediments   总被引：17，自引：0，他引：17  
This investigation represents the first extensive study of the spatial distribution and sources of aliphatic (n-alkanes and unresolved complex mixture of fossil hydrocarbons) and polycyclic aromatic hydrocarbons (PAHs) in coastal sediments from the Caspian Sea. PAH concentrations, n-alkanes and biomarker profiles all suggested that there was limited petrogenic contamination in the shallow North Caspian Sea sediments, which are coarse with a low total organic carbon content. In contrast, moderate to high petrogenic contamination was found in the South Caspian Sea, in particular in the offshore oil fields near Baku, Azerbaijan. Contaminant patterns indicated that the PAHs were mainly from fossil sources, with higher contributions of pyrolytic only near industrialized and urban areas. A high contribution of perylene, a geochemically derived PAH, to the total PAHs was found in the west and south at sites influenced by the Kura, Safid Rud, Terek, Sulak and Samur Rivers.  相似文献   

4.
《Marine pollution bulletin》2012,64(5-12):464-470
This study measured concentrations of polycyclic aromatic hydrocarbons (PAHs) in surface sediments in the East China Sea (ECS) to investigate possible sources and fate of PAHs. Total concentration of PAHs in the sediments of the ECS ranged from 22 to 244 ng g−1, with the highest levels in the coastal area and outer shelf. The observed PAH results showed elevated levels in both inner and outer shelf areas, a finding that is different from predictions by an ocean circulation model, suggesting that terrestrial sources are important for PAH contaminations in the ECS, while sediment resuspension, tidal changes and lateral transport may be important in affecting the distribution of PAHs in the outer shelf. The distribution of PAHs in the surface sediments of the ECS is similar to the distribution of carbonaceous materials (e.g., particulate organic carbon and black carbon), suggesting that carbonaceous materials may strongly affect the distribution of PAHs.  相似文献   

5.
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   

6.
A field operable surface enhanced Raman scattering (SERS) sensor system was applied for the first time under real conditions for the detection of polycyclic aromatic hydrocarbons (PAHs) as markers for petroleum hydrocarbons in the Gulf of Gdańsk (Baltic Sea). At six stations, seawater samples were taken, and the sensor system was applied in situ simultaneously. These measurements were compared to the results of conventional GC/MS laboratory analysis of the PAH concentrations in the seawater samples. For a PAH concentration above 150 ng(12PAH)l(-1), there was agreement between the SERS sensor and the GC/MS determinations. A standard addition experiment yielded a PAH concentration of 900 ng l(-1) at the Gdańsk Harbor, which was of the same order as the GC/MS determinations of 12PAHs (200 ng(12PAH)l(-1)). The high SERS detection limit for seawater samples is explained by the competition for PAHs between the sensor membrane and particulate matter surfaces. Thus, the SERS sensor can be applied, e.g., as a non-quantitative alarm sensor for relatively high PAH concentrations in heavily polluted waters. The spectral unmixing procedure applied for Gdańsk Harbor water confirmed the presence of phenanthrene at the highest concentration ([Phe]=140 ngl(-1)) and of Chr (2.7 ng l(-1)), but it did not detect the other PAHs present in the Gdańsk Harbor water, as determined by GC/MS. When compared to the past literature and databases, the SERS spectra indicated the presence of a mixture of molecules consisting of carotenoids, n-alkanes, amines or fatty acids, and benzimidazoles at the coastal station ZN2. The spectra in the offshore direction indicated carboxylic acids. Interpretation of the farthest offshore in situ SERS measurements is difficult, principally due to the limited availability of reference spectra. The detection of the lower PAH concentrations commonly found in Baltic coastal water needs further research and development to obtain better sensitivity of the SERS sensor. However, the high analytical specificity of the SERS sensor also allows the detection of other chemical species that require the development of a SERS/Raman library for specific in situ spectral interpretation.  相似文献   

7.
The nature, origin and distribution of US EPA polycyclic aromatic hydrocarbons (PAHs) in the sediments of Olbia harbor (North Sardinia, Italy) were investigated by gas-chromatography/mass spectrometry (GCMS). PAH concentrations in the sediments (SigmaPAHs) ranged from 0.16 to 0.77 microg g(-1), indicating a homogeneously low level of pollution. A rather exceptional prevalence of low molecular weight PAHs was substantiated: nearly 80% of SigmaPAHs include naphthalene (15.19%) and phenanthrene (64.47%). Carcinogenic compounds were present in very low (BaP, BkF, BaA and DBA) or negligible (BbF and Inp) concentrations. As indicated by the Phen/Ant molar ratio, the main source of PAHs is petrogenic, probably due to oil spills from shipping. The low/high molecular weight ratio (ranging between 1.2 and 26) distinguishes the sediments of the tourist harbor from those of the commercial/industrial harbor. Moreover, a slight but meaningful pyrolytic contribution to pollution was found in the tourist harbor, which has the most polluted sediments in the whole harbor. Finally, good linear correlations were found between a selected PAH (Phen and Naph) and selected sums of PAHs (i.e. the total amount of the other 15 US EPA and the sum of low molecular weight PAHs).  相似文献   

8.
During the late 1950s and early 1960s of the past century, industrial waste material highly enriched in various contaminants (heavy metals, PAHs) was dumped in the inner Mecklenburg Bay, western Baltic Sea. Large-scale shifts in the spatial distribution of heavy metals in surface sediments were mapped by geochemical monitoring in the mid-1980s and 12 years later in 1997. A further study in 2001 was designed to investigate the small-scale spatial distribution of contaminants inside, on top of, and around the historical dumping ground and to examine possible effects to benthic organisms (Arctica islandica, microbiological toxicity tests). The site is located within an area characterized by a discontinuous deposition of fine sediments, but net sedimentation rate of about 3mm/y led ultimately to a gradual coverage of the dumped material. During the first decades after the dumping, about half of the originally dumped material was already spread over the surrounding area as a result of sediment dynamics and re-suspension processes. Recent sediments of the historical dump site are still significantly enriched in heavy metals and PAHs. Microbiological toxicity test results were positive, though uptake of contaminants in mussels was found to deviate only slightly from that of a non-contaminated reference station due to a gradual dilution and decrease in bioavailability of the contaminants.  相似文献   

9.
The composition and distribution of aliphatic (n-alkanes) and polyaromatic hydrocarbons (PAHs) were measured for the surface sediments collected at 25 sites from Jiaozhou Bay, Qingdao, China. Total n-alkanes and PAH concentrations ranged from 0.5 to 8.2 microg/gdw and 0.02 to 2.2 microg/gdw, respectively, and the distribution of both n-alkanes and PAHs showed large spatial variations in the bay. The distribution of PAHs in the sediments was predominated by the three or more ring compounds. High hydrocarbon levels were generally found in the areas associated with high anthropogenic impact and port activities in the bay. The calculated hydrocarbon indexes suggest that petroleum contamination was the main source of n-alkanes, while both pyrolytic and petrogenic sources contributed PAHs to the surface sediments of Jiaozhou Bay. In comparison to other polluted coastal sediments, the level of contamination from both aliphatic hydrocarbons and PAHs in Jiaozhou Bay sediments is relatively low at the present time.  相似文献   

10.
Polychlorinated biphenyls (PCBs) and 17 parent polycyclic aromatic hydrocarbons (PAHs) were determined in surface sediments from nine stations in the Mar Piccolo of Taranto (Ionian Sea, Southern Italy). Total PAH concentrations ranged from 380 to 12,750 microg/kg d.w., while total PCB levels ranged from 2 to 1684 microg/kg d.w.; this values were higher than those found in others marine coastal areas of the Mediterranean Sea. For PAHs, low molecular weight/high molecular weight, phenanthrene/anthracene and fluoranthene/pyrene ratio were used for discriminating between pyrolitic and petroleum origin. Results showed that PAHs were mainly of pyrolitic origin. PCB and PAH levels in sediments were compared with Sediments Quality Guidelines (ERM-ERL, TEL-PEL indexes) for evaluation probable toxic effects on marine organism. Finally, ERM and PEL quotients were used to evaluate the degree to which chemicals exceed guidelines. Results suggest an ecotoxicological risk for benthic organisms mainly in the first inlet, where high concentrations of PCBs were found in sediments influenced by harbour activities.  相似文献   

11.
To document the historical input the PAH-profiles of sediment cores in two different basins of the Baltic Sea, the Gotland Basin (GB) and Arkona Basin (AB), were analysed by means of GC-MS. 35 PAHs were quantified in all samples, and additionally, several marker PAHs, like Cyclopenta[cd]phenanthrene (CCP) for combustion processes and retene for terrigenous input, were quantified in selected samples. The preindustrial sediments (older than 200-250 years) in the GB core illustrate concentrations <100 ng PAH15 g(-1) d.w. Calculated PAH-ratios indicated combustion processes as the main sources for both basins. The Perylene concentrations within the sediment cores decrease with increasing depth, along with an increase in relative percentage, indicating slow diagenetic processes. The preservation and enrichment of the introduced PAHs was more pronounced in the GB core.  相似文献   

12.
The fate of polycyclic aromatic hydrocarbon (PAH) contamination in a mangrove swamp (Yi O) in Hong Kong after an oil spill accident was investigated. The concentrations and profiles of PAHs in surface sediments collected from five quadrats (each of 10 m×10 m) covering different degrees of oil contamination and the most contaminated mangrove leaves were examined in December 2000 (30 days after the accident) and March 2001 (126 days later). The concentrations of total PAHs in surface sediments ranged from 138 to 2135 ng g−1, and PAHs concentrations decreased with time. In the most contaminated sediments, total PAHs dropped from 2135 (30 days) to 1196 ng g−1 (120 days), and the decrease was smaller in less contaminated sediments. The percentage reduction in sediment PAHs over three months (44%) was less significant than that in contaminated leaves (85%), indicating PAH in or on leaves disappeared more rapidly. The PAH profiles were very similar in sediments collected from quadrats Q1 and Q2 with benzo[a]anthracene and pyrene being the most abundant PAH compounds, but were different in the other three quadrats. The proportion of the light molecular weight PAHs to total PAHs increased after three months, especially phenanthrene. Results suggest that physical and photo-chemical weathering (tidal washing and photo-oxidation) of crude oil in surface sediments and on plant leaves were important processes in the first few months after the oil spill. The PAH contamination in Yi O swamp came from both petrogenic and pyrolytic sources. The petrogenic characteristic in the most contaminated sediment was confirmed with high values of phenanthrene to anthracene ratio (>10) and low values of fluoranthene to pyrene ratio (0.3–0.4).  相似文献   

13.
The rivers in the Baltic Basin drain a mixture of bedrocks ranging from Mesozoic-Paleozoic sediments in the south to Proterozoic-Archean intrusives in the north. The rivers in the sedimentary basin in the south have high concentrations of Sr, in the interval 100–500 µg l–1 while the87Sr/86Sr ratio is close to that of seawater, i.e. 0.71. The northern rivers in the Precambrian shield area on the other hand have low Sr concentrations of 15–50 µg l–1 with high87Sr/86Sr ratios of about to 0.73 (0.721–0.745). The riverine input of dissolved Sr to the brackish Baltic Sea approaches 60 tons year–1, with a weighted mean concentration approaching 130 µg l–1 and a weighted mean87Sr/86Sr ratio close to 0.712. Although the sedimentary area in the south supplies only about 43% of the total river discharge, it gives about 88% of the total Sr input. Because of this and the strong regional riverine variation in87Sr/86Sr ratio, Sr and its isotopes seem to be a convenient tool to unveil mixing relations of water masses in the northern Baltic Sea, provided high resolution analyses are applied. For an overall characterization of water mixing in the Baltic Sea, the Nd system will be superior to that of Sr.  相似文献   

14.
The article gives the results of studying the concentration and composition of aliphatic and polycyclic aromatic hydrocarbons in suspension in surface waters at sections from the English Channel and Skagerak Strait to various regions of the Baltic Sea (2010–2015) and in water and bottom sediments of the southeastern part of the sea in the water area of the Kravtsovskoe field (2008–2015). In recent years, the surface waters of open areas of the Baltic Sea showed a decrease in hydrocarbon concentrations down to background levels (12–33 μg/L). The maximal concentration of hydrocarbons (in excess of the MAC) was recorded in different seasons in navigation areas, including the English Channel and Pregola R. mouth. In the zone of the Kravtsovskoe field, the concentration and composition of hydrocarbons in water depends on their inflow from the bank, and the same characteristics in bottom sediments, on the rate of their leakage from sediment stratum. A decline in these processes have led to a decrease in hydrocarbon concentrations in the sediments of a local area near D-6 platform to background levels (5–7 μg/g) and to the predominance of terrigenous, rather than petroleum, alkanes in hydrocarbon compositions.  相似文献   

15.
《Marine pollution bulletin》2008,56(10-12):451-458
Polychlorinated biphenyls (PCBs) and 17 parent polycyclic aromatic hydrocarbons (PAHs) were determined in surface sediments from nine stations in the Mar Piccolo of Taranto (Ionian Sea, Southern Italy). Total PAH concentrations ranged from 380 to 12,750 μg/kg d.w., while total PCB levels ranged from 2 to 1684 μg/kg d.w.; this values were higher than those found in others marine coastal areas of the Mediterranean Sea. For PAHs, low molecular weight/high molecular weight, phenanthrene/anthracene and fluoranthene/pyrene ratio were used for discriminating between pyrolitic and petroleum origin. Results showed that PAHs were mainly of pyrolitic origin. PCB and PAH levels in sediments were compared with Sediments Quality Guidelines (ERM–ERL, TEL–PEL indexes) for evaluation probable toxic effects on marine organism. Finally, ERM and PEL quotients were used to evaluate the degree to which chemicals exceed guidelines. Results suggest an ecotoxicological risk for benthic organisms mainly in the first inlet, where high concentrations of PCBs were found in sediments influenced by harbour activities.  相似文献   

16.
The seasonal vertical distribution of particulate matter (PM) was studied in two contrasting areas: (a) the mesotrophic Skagerrak (in the North Sea); and (b) the oligotrophic northeastern Aegean Sea (eastern Mediterranean). Similarities and differences of the PM distribution in the two areas are assessed with respect to the prevailing hydrographic conditions and the PM composition. Hydrographic conditions in both of the areas are characterised by strong density gradients, resulting from the inflow of low-salinity water, i.e. Baltic Sea water and Black Sea water for the Skagerrak and the northeastern Aegean Sea, respectively.Enhanced primary production and particles mainly of biogenic origin characterise the mesotrophic Skagerrak, whereas five-fold lower particle concentrations appeared in the oligotrophic Aegean Sea. The input of riverine particulates was limited in both of the areas. In the Skagerrak, the strong stratification resulted in particle accumulation on/above the pycnocline and the development of pronounced intermediate nepheloid layers (INLs). The pycnocline-related INLs were formed entirely by dinoflagellates. The pycnocline hindered the vertical movement and sinking rates of particles, thus favouring primary production. Particle horizontal advection along the density discontinuities was probably enhanced. This pattern was not observed in the stratified waters of the northeastern Aegean Sea, probably due to the very low particle concentrations and/or the fact that phytoplankton maxima appeared in deeper waters. Pronounced INLs were identified in the Skagerrak below the pycnocline; these are attributed to accumulated or advected dinoflagellate skeletal remains mixed with clay mineral particles. This was revealed only by means of SEM observations. X-ray diffraction analysis could not provide information on the type of phytoplankton present, because dinoflagellates form their skeletons from organic material. Frontal stations in the northeastern Aegean Sea exhibited pronounced vertical movement of particles towards the deeper waters. Benthic nepheloid layers (BNL) were observed in the Skagerrak; these were related to the resuspended fine-grained surface sediments. In the northeastern Aegean Sea, although near-bottom current velocities were sufficient to resuspend surface sediments, resuspension occurred only episodically. The BNLs here are related mostly to near-bottom phytoplankton growth.  相似文献   

17.
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   

18.
The composition and spatial distribution of aliphatic and polycyclic aromatic hydrocarbons (PAHs) were investigated in biota and coastal sediments from four countries surrounding the Gulf (Bahrain, Qatar, United Arab Emirates and Oman). The levels of total petroleum hydrocarbons (TPH), aliphatic unresolved mixture and PAHs in sediments and biota were relatively low compared to world-wide locations reported to be chronically contaminated by oil. Only in the case of the sediments collected near the BAPCO oil refinery in Bahrain, having concentrations of 779 μg g−1 total petroleum hydrocarbon equivalents and 6.6 μg g−1 ∑PAHs, can they be categorized as chronically contaminated. Some evidence of oil contamination was also apparent in sediments and bivalves around Akkah Head and Abu Dhabi in the UAE, and near Mirbat in Oman. Contaminant patterns in sediments and biota indicated that the PAHs were mainly from fossil sources, with the exception of the high PAH concentrations in sediments near the BAPCO refinery that contained substantial concentrations of carcinogenic PAH combustion products.  相似文献   

19.
Two research cruises on the Baltic Sea, in July and November of 1979, were made for investigating the Baltic Sea water for its contents of dissolved cadmium, lead and copper. Atomic absorption spectrophotometry and voltammetry were used as methods of investigation, the latter method having supplied slightly lower results. In the water layer of 0 … 50 m the cadmium concentrations were 0.03 … 0.05 μg/l and the lead concentrations were 0.1 … 0.2 μg/l, seasonal changes did not have any effect on them. The copper concentrations, on the other hand, were 0.4 … 1.2 μg/l in summer and 0.1 … 0.7 μg/l in autumn. Compared with ocean waters, the lead content is remarkably high. In anoxic deep waters of the Baltic Sea the concentrations of the three metals, especially that of cadmium, are very low (< 0.01 μg/l).  相似文献   

20.
The concentrations of 16 US EPA priority pollutant polycyclic aromatic hydrocarbons (PAHs) were analyzed in four size fractions (< 62, 62-125, 125-250, and > 250 microm) in three contaminated Boston Harbor sediments. Total PAH concentrations ranged from 7.3 to 358 microg/g dry wt. and varied largely among the different size fractions in these sediments. For all three sites, the highest PAH concentrations were associated with the large size (> 250 microm) fractions while the fine silt and clay fractions (< 62 microm) contained relatively low PAHs. Despite the great concentration differences, the composition of PAHs in the four size fractions of these sediments showed similar patterns dominated by PAHs with three or more rings. By examining the distribution patterns of selected alkyl homologs to parent compounds, the results indicate that the major PAHs contributing to the high contamination in the inner harbor sediments were from pyrogenic sources. A positive correlation between PAHs and sedimentary organic carbon exists for all size fractions in the sediments. Calculated organic carbon normalized partition coefficients (log K(oc)) for selected major PAHs indicate near-equilibrium partitioning of PAHs among the different size fractions despite their large concentration variations. Sedimentary organic matter associated with different size fractions was the controlling factor for the observed distribution differences of PAHs among the size fractions. Our results also suggest that sedimentary organic matter with different origins and maturities may have somewhat different PAH sorption characteristics. Particulate organic matter of charcoal, plant detritus and Capitella fecal pellets in the sediments appear to sorb PAHs more strongly than organic matter associated with clay minerals. The strong association of PAHs with these organic particles in sediments will have a great influence not only on their distribution but also on long-term environmental impact.  相似文献   

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