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1.
During the Danish Galathea 3 expedition, bivalve samples were collected at the Faroe Islands, Greenland, Ghana, South Africa, Australia, Solomon Islands, New Zealand, Chile, US Virgin Islands, Boston, Newfoundland and Shetland Islands and analysed for organochlorines and PAHs. Concentration differences of up to three orders of magnitude were observed, with the highest concentrations at Boston harbour (SPCB 338 ng g(-1) dw, ΣSPAH 5966 ng g(-1) dw) and the Sydney estuary (ΣSPCB 282 ng g(-1) dw, SPAH 1453 ng g(-1) dw). Local impacts were also found for the Greenland capital Nuuk in terms of PCB and PAH levels, while other Greenland samples came closest to representing PAH background levels. Several locations had undetectable organochlorine levels, including Hobart and Chile, which had the lowest SPAH concentrations (<200 ng g(-1) dw). It was possible to group the stations according to their pyrogenic/petrogenic influence using Principal Component Analyses, and indications of petroleum sources were found at Nuuk.  相似文献   

2.
This study was performed to elucidate the distribution, concentration trend and possible source of polycyclic aromatic hydrocarbons (PAHs) in surface water and bed sediments of the Hungarian upper section of the Danube River and the Moson Danube branch. A total of 217 samples (water and sediments) were collected from four different sampling sites in the period of 2001–2010 and analysed for the 16 priority US Environmental Protection Agency PAHs. Concentrations of total 16 PAHs (∑PAHs) in water samples ranged from 25 to 1,208 ng/L, which were predominated by two- and three-ring PAHs. The ∑PAH concentrations in sediments ranged from 8.3 to 1,202.5 ng/g dry weight. Four-ring PAHs including fluoranthene and pyrene were the dominant species in sediment samples. A selected number of concentration ratios of specific PAH compounds were calculated to evaluate the possible sources of PAH contamination. The ratios reflected a pattern of pyrogenic input as a major source of PAHs. The levels of PAHs determined were compared with other sections of the Danube and other regions of the world.  相似文献   

3.
A maar lake is an excellent ecosystem to study the atmospheric deposition of pollutants, as its contaminants are primarily by atmospheric deposition. In this study, a sediment core from Sihailongwan Maar Lake, Northeast China, was collected and the historical atmospherically deposited polycyclic aromatic hydrocarbons (PAHs) were analyzed. The concentrations of TPAHs (the sum of the US EPA proposed 16 priority PAHs, excluding naphthalene and pyrene) ranged from 473.9 to 2289 ng g(-1) with a slow increasing stage in the deeper sediments and a sharp increasing stage in the upper sediments. The input rate of TPAHs, especially that of PAH(9) (the sum of fluoranthene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, indeno(1,2,3-cd)pyrene, dibenzo(ah)anthrathene, and benzo(ghi)perylene), correlated well to the Chinese historical socioeconomic data. This indicates that sediment PAHs were mainly derived from human activities and PAH(9) can be regarded as a better indicator of the local socioeconomic development. Source identification suggested that PAHs were originated primarily from mixed sources (e.g., coal and biomass burning and petroleum combustion), except for perylene which was mostly of diagenetic origin. In addition, the down-core PAHs profile clearly illustrated that PAHs sources in Northeast China experienced a transformation from low- and moderate temperature to high-temperature combustion processes, especially after the late 1980s. Additionally, an ecological risk assessment using two redefined biological thresholds (TEQ(ERL) and TEQ(ERM)) indicated that most of the PAHs measured in the present sediment core would not cause an immediate toxic effect; only FLU and PHEN are a potential source of concern for biological impairment.  相似文献   

4.
Harbours of La Goulette, Rades and Sidi Bou Said are considered as the principal largest and most important port in the Gulf of Tunis characterised by a direct influence of different activities (sailing, industry and fishing) to the Mediterranean Sea. Due to their social and economic impact, a comprehensive assessment of the spatial distribution and partitioning of 24 polycyclic aromatic hydrocarbons (PAHs) and 18 aliphatic hydrocarbons (AHs) in summer and in winter among overlying water, suspended particulate matter (SPM) and surface sediments is essential. Distribution of hydrophobic organic contaminants in abiotic compartments is important for describing their transfer and fate in aquatic ecosystems and to identify the potential danger due to mobilization of contaminants produced by managing of the same sediments. Total organic carbon (TOC) contents range between 4.3% and 6.5%, with an average value of 5.9% in summer, and between 2.3% and 9.6%, with an average value of 6.1% in winter. The average concentrations of ΣPAH in winter and in summer were respectively 703.1 ng L?1 and 378.4 ng L?1 in seawater, 4599.1 ng g?1 and 3114 ng g?1 in SPM, and 1507.6 ng g?1 dw (dry weight) and 1294.6 ng g?1 dw in surface sediment. For ΣAH the average concentrations in winter and in summer were respectively 701 ng L?1 and 741.7 ng L?1 in seawater, 6743.5 ng g?1 and 6282.9 ng g?1 in SPM, and 4971.3 ng g?1 and 4588.1 ng g?1 in surface sediment. Higher PAH and AH concentrations were observed in SPM than in surface sediment. SPM and water were dominated by PAH with low molecular weight, while for sediment low and high molecular weight PAHs were present. PAH and AH fingerprint ratios, such as pristane to phytane (Pr/Ph), phenanthrene to anthracene (Phe/An) and fluoranthene to pyrene (Fl/Py), suggest that hydrocarbons in all harbours may originate from both pyrolytic and petrogenic sources derived from discharge of untreated sewage and wastewater or from direct input by ship traffic in the area. The results showed significant difference (ANOVA, p < 0.05) for hydrocarbon mean concentrations between all harbours studied and between different matrixes.  相似文献   

5.
Surface sediment samples were collected in He-Ping Harbor and the nearby He-Ping Estuary from 2005 to 2006 to examine spatial and temporal variability in polycyclic aromatic hydrocarbon (PAH) concentrations. The sum of the 16 USEPA priority pollutant PAHs varied from 8 to 312 ng/g dry weight, which was relatively low compared to values obtained from other studies in the world. Regarding temporal changes in the PAH profile, total PAH concentrations in the wet season were lower than during the dry season in He-Ping Harbor. However, the concentration of PAHs exhibited no significant difference in the four seasons in the He-Ping Estuary. PAH concentrations in He-Ping Harbor were higher than those in the He-Ping Estuary. In comparison with sediment quality guidelines, PAH concentrations of sediments in this study were lower than those outlined in the criteria, which suggests no evident adverse biological effects due to PAHs around the He-Ping coast. Ratios of specific PAH compounds calculated to assess the possible sources of PAHs reflect that PAHs in He-Ping Harbor may mainly be from pyrogenic coal combustion.  相似文献   

6.
Sources, partitioning and toxicological risk of 15 priority polycyclic aromatic hydrocarbons (PAHs) in surface sediments from drinking water sources of Taihu Lake, with an area of 2428 km(2) located in the most developed and populated area of China, were studied, and the results were compared with those in other lakes of China and the USA. Concentrations of the 15 PAHs in sediments ranged from 436.6 to 1334.9 ng g(-1) (dw). Gasoline combustion, coal combustion, diesel combustion from shipping and spillage of petroleum were apportioned to be the main sources of PAHs in this area by principal component analysis, which contributed 35.19%, 26.43%, 25.41% and 12.97% to the PAH sources estimated by further multiple linear regression. Levels of PAHs in sediments were negatively correlated with contents of clay and fine silt (<16 μm), while positively with contents of medium silt, coarse silt and sand (>16 μm). Humin with size larger than 16 μm contained the largest part of the burden of PAHs in sediments, but the specific partitioning domain (bound humic acid, lipid or insoluble residue) depended on properties of organic matter reflected by optical absorbance at 465 and 665 nm. Total toxic benzo[a]pyrene equivalent (TEQ(carc)) of the carcinogenic PAHs in sediments varied from 31.8 to 209.3 ngTEQ(carc) g(-1). Benzo[a]pyrene and dibenzo[a,h]anthracene contributed 45.36 and 25.31% to total TEQ(carc), posing high toxicological risk to this area.  相似文献   

7.
In this paper, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in biota (reed, grass, mussel, fish, and red-crowned crane) and sediments collected from seven locations in the Zha Long Wetland. PAHs were recovered from the sediments and biota by ultrasonic extraction and then analyzed by means of gas chromatography-mass spectrometry. The total PAH concentrations were 244–713 ng/g dw in sediments, 82.8–415 ng/g dw in plants and 207–4,780 ng/g dw in animals. The total sediment PAH concentrations were categorized as lower to moderate contamination compared with other regions of China and the world. In the plant samples, the accumulation abilities of reed roots and stems for PAHs were higher than those of grass roots. In addition, the concentration of individual PAHs in mussel muscles was the highest in all of the animal samples, followed by fish, feeding crane fetuses, and wild crane fetuses. Compositional analysis suggests that the PAHs in the sediments from the Zha Long Wetland were derived from incomplete biomass combustion. Risk assessment shows that the levels of PAHs in sediments are mostly lower than the effects range mean value (effects range mean), whereas only naphthalene in all sample sites was higher than the effects range low value. It is worthwhile to note that benzo(b)fluoranthene, benzo(k)fluoranthene, indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were detected in crane fetal, which have potential carcinogenicity for organisms from the Zha Long Wetland.  相似文献   

8.
The concentration, distribution, and origin of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) were investigated in river sediments from the western and southern catchments of the Bohai Sea, China. A toxicity assessment of 28 sediment samples collected from 15 main rivers was conducted by utilizing threshold and probable effect concentrations (TEC and PEC, respectively) derived from consensus-based sediment quality guidelines. The concentrations of total PAHs (∑PAH16) ranged from 0.14 to 10,757 μg/kg dry weight (mean?=?1,368.6 μg/kg). The high concentrations of PAHs found in Binhai New Area of Tianjin and Binzhou City are likely the result of rapid population and heavy industry growth, resulting in elevated point and nonpoint source inputs of PAHs. Of the samples collected, samples 1 and 10 (7.1 % of the total) were categorized as toxic since some of the PAH concentrations exceeded the corresponding PECs. Twenty samples were classified as nontoxic, with both the individual PAH and the∑PAH16 concentrations falling below the corresponding TECs. Analyses of selected PAH isomer ratios aided in the identification of PAH origins, allowing for a discrimination between pyrogenic and petrogenic sources. Spatial variability confirmed source heterogeneity within the study area. The most significant PAH-associated contamination was found in the Beitang River and Ji Canal, which are located in Binhai New Area. The magnitude of contamination and the likelihood of an ongoing influx of PAHs support the need for a better understanding of pollution sources and methods for both control and sediment restoration.  相似文献   

9.
62 riverine and marine sediments were collected from the Laizhou Bay area, where the largest manufacturing base of brominated flame retardants (BFRs) in Asia is located. Eight polybrominated diphenyl ethers (PBDEs) were analyzed to investigate the impact of rapidly-developed bromine industries on the regional aquatic system. PBDE concentrations varied largely in riverine sediments. Σ(7)PBDEs (including BDE 28, 47, 99, 100, 153, 154 and 183) and BDE 209 ranged from 0.01 to 53 ng g(-1) dw and from 0.74 to 285 ng g(-1) dw with a mean value of 4.5 ng g(-1) dw and 54 ng g(-1) dw, respectively, indicating a strong influence of direct pollution discharges from local factories. In marine sediments, Σ(7)PBDEs and BDE 209 ranged from not detected (nd) to 0.66 ng g(-1) dw and from 0.66 to 12 ng g(-1) dw with a mean value of 0.32 ng g(-1) dw and 5.1 ng g(-1) dw, respectively. PBDE concentrations were mostly <10 ng g(-1) dw for Σ(7)PBDEs and <50 ng g(-1) dw for BDE 209, which are at a relatively low level for monitored riverine and coastal sediments around the world. Even at the most contaminated sites in Laizhou Bay area, PBDE concentrations were not among the highest concentrations reported in the literature. Congener compositions were dominated by BDE 209 (57.2-99.9% of the sum of BDE congeners), with minor contributions from penta- and octa-BDE products. Tri- to octa-BDE congeners were well correlated among each other (r > 0.75) and thus sources from similar mixing of penta- and octa-BDE products were suggested in this area. Compared with riverine sediments, a much better correlation between PBDE concentrations with TOC was observed in marine environment. The congener pattern changed and their correlation coefficients among each other were remarkably reduced. Contributions of BDE 28, 47 and 99 to Σ(7)PBDEs were generally the same in almost all the marine sites, while it was distinctively higher for BDE 153. These are probably attributable to several reasons, such as contributions by atmospheric deposition and/or redistribution between particles of various sizes during and/or after fluvial transportation combined with the difference of physiochemical properties of BDE congeners.  相似文献   

10.
Polycyclic aromatic hydrocarbons (PAHs) were quantified in sediment, soil, and plant material from Hanoi, Vietnam, and an aquatic production system in peri-urban Hanoi. The sum of the concentration of 16 US-EPA priority PAHs ( summation PAH16) ranged between 0.44 and 6.21 mg kg(-1) dw in sediment and between 0.26 and 1.35 mg kg(-1) dw in soil, with decreasing concentrations from the urban area to the peri-urban area, indicating contributions from urban and industrial sources. Double plots of diagnostic source ratios indicate that PAHs originate from mixed petrogenic and pyrogenic sources, the latter being predominant. The predominance of low molecular weight (LMW) PAHs in the sediment samples suggests that petrogenic sources are more prevalent in the water environment than in the soil. In contrast, high molecular weight (HMW) PAHs dominated in water spinach which probably reflects the plant's uptake of particle-bound PAHs that originate from pyrogenic sources.  相似文献   

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