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1.
The paper reviews data (acquired in 2007–2016) on aliphatic and polycyclic aromatic hydrocarbons in comparison with data on concentrations of lipids, Corg, and chlorophyll a in the water and bottom sediments the river–sea geochemical barrier (for the Northern Dvina, Ob, Yenisei, and Lena rivers). It was established that the concentrations of anthropogenic hydrocarbons decrease and these compounds precipitate like other organic compounds and particulate matter, where riverine and marine waters mix. Relatively pure water flows in the pelagic zones of seas. In spite of low temperatures in the Arctic, anthropogenic hydrocarbons transform so rapidly that natural compounds dominate in the water and bottom sediments: autochthonous in the seawater and allochthonous in the bottom sediments.  相似文献   

2.
Aliphatic and polycyclic aromatic hydrocarbons were examined in the surface layer of bottom sediments from the eastern part of the Sakhalin shelf (the materials were sampled in the summer of 2002). The concentrations of hydrocarbons were determined to have changed since the beginning of the development of oil fields (compared with earlier years). According to the distribution of markers in the hydrocarbon compositions, the bottom sediments are dominated by allochthonous (terrigenous) hydrocarbons, which are the most stable compounds. The presence of transformed anthropogenic oil alkanes, which have never been found before, may be indicative of the increasing pollution of the region.  相似文献   

3.
A study of two classes of hydrocarbons (HCs)—aliphatic and polycyclic aromatic—in suspended matter of the surface waters and bottom sediments of the Northern and Middle Caspian Sea (R/V Nikifor Shurekov, October 2015) is described. It has been determined that oil pollution transported by river runoff and fluid streams flowing from sedimentary formations in the northeastern part are the main sources of hydrocarbons in the river–sea boundaries of the Volga, Terek, and Sulak rivers.  相似文献   

4.
拉萨市拉鲁湿地多环芳烃污染及其来源   总被引：9，自引：0，他引：9  
通过分析采集的土壤、沉积物和大气样品,对拉萨郊区的拉鲁湿地多环芳烃污染及其来源进行了初步研究.湿地表层土壤中16种多环芳烃的平均含量的总含量为82.45×10-9,既存在低环数的多环芳烃,又含有高环数的多环芳烃;湿地土壤中的多环芳烃主要来自于大气.  相似文献   

5.
Doklady Earth Sciences - The concentration of polycyclic aromatic hydrocarbons in the water of Lake Baikal is estimated. The published data on the composition of polycyclic aromatic hydrocarbons in...  相似文献   

6.
Sediment analysis is used for detecting pollution sources; in addition, sediments are increasingly investigated as a pollution proper and as a carrier and possible source of contaminants in aquatic systems. Amongst the various groups of pollutants which possess a strong affinity to sedimentary materials, heavy metals and polycyclic aromatic hydrocarbons present the greatest environmental hazard. A review is given of pre-civilisational concentrations (“background” values) of both heavy metals and polycyclic aromatic hydrocarbons in fluviatile sediments, and their development during the past 100 years. The impact of sediment associated heavy metal pollution on both biota and water is discussed.  相似文献   

7.
This study aimed to evaluate the total concentration of polycyclic aromatic hydrocarbons in sediments of Iguassu River in Southern Brazil. Alongside the concentration, the amount of such compounds bioavailable was also evaluated. This is accomplished by comparing its total amount present in sediments and the amount extracted by n-butanol. The results showed that the total concentration of polycyclic aromatic hydrocarbons presented in sediment ranged from 4.49 to 58.75???g/g. The total amount of polycyclic aromatic hydrocarbons extracted by n-butanol ranged from 1.22 to 17.07???g/g. The use of n-butanol represents the mimetic conditions that hydrocarbons, derived from oil, could be taken up by organisms. Most of the hydrocarbons extracted by n-butanol were those with lower octanol?Cwater partition constant, usually those with three and four rings. Compounds with more than four rings were extracted in lower or insignificant amounts. Even the hydrocarbons with lower molecular weight available may be degraded or eliminated by organisms, when accumulated. Estimating bioavailability of hydrocarbons represents what specific hydrocarbons could be available to be taken up by organisms.  相似文献   

8.
The evaluation of potential environmental impacts from polycyclic aromatic hydrocarbon is a subject that requires investigation, especially related to emission sources from highway roads with high traffic. In this paper, the distribution of polycyclic aromatic hydrocarbons was investigated in the surface sediments from a subtropical lake, located in the south of Brazil and away from urban areas. The results showed that all sediments presented such compounds in significant concentration, ranging from 9.50 to 29.88???g/g. The highest total concentration was found in those sites close to the highway (bridges) and the deepest area of the lake. Moreover, a high concentration of polycyclic aromatic hydrocarbons of high molecular weight, such as benzo(a)anthracene and dibenzo(a,h)anthracene was found. It was laso found that high concentrations might be related to asphalt and coal tar pavement used in the highway construction close to the lake. In addition, the potential capacity of sediment toxicity was compared with values of the interim sediment quality guidelines values. The results indicate that most of the sediment presents concentrations of hydrocarbons above these limits. Only fluoranthene and chrysene were found in concentrations below the guideline values. The concentrations of most of the polycyclic hydrocarbons are higher than the quality guidelines. However, the main concern is associated with the presence of benzo(a)anthracene whose concentration is 416 times higher than the limit establisehed by guidelines. The same observation can be done to traces of benzo(a)pyrene and dibenz(a,h)anthracene, with concentration values of 13 and 1,993 times higher.  相似文献   

9.
南黄海中部海水中多环芳烃的分布特征   总被引：1，自引：0，他引：1  
2007年9月进行了2007南黄海海洋环境调查,并采集各个调查站位的表层、中层、底层海水及表层沉积物。利用液-液萃取法对采集到的样品进行前处理,并用气相色谱-质谱法检测海水中的多环芳烃。结果显示,监测站位中表层海水中总多环芳烃的含量范围是15.76~233.39ng/L,南黄海中部海水中多环芳烃的组成以2环的萘为优势组分;各种多环芳烃的含量与国际生物学组织或国家制定的评价水生生物暴露于水体的安全食用标准相比虽未超标,但个别组分如荧蒽的含量已达到生态毒理评价标准。  相似文献   

10.
Petroleum potential of Baikal deposits   总被引：1，自引：0，他引：1  
We analyzed oils, gases, and bitumens of bottom sediments from natural shows on the southeastern shore of Lake Baikal, in the mouth of the Stvolovaya River near Capes Tolstyi and Gorevoi Utes. Based on a set of geological data, we have established that: (1) the lake oils underwent biodegradation to a variable degree: “Fresh” nondegraded paraffin oil floats up near Cape Gorevoi Utes; in the mouth of the Stvolovaya River and near Cape Tolstyi, aromatic-naphthene oil lacks n-alkanes, monomethyl alkanes, and acyclic isoprenoids; (2) Cenozoic oil originated from the organic matter of fresh-water basins with significant amounts of higher land plant remains, including angiosperm plants (oleanane), which suggests the lake or delta genesis of oil source formations of Cretaceous and younger ages. Judging from the carbon isotope composition (average δ13C = −43.84‰), methane from the bottom sediments near Cape Gorevoi Utes is catagenetic. The initial in-place resources in the Baikal sedimentary basins are estimated by the volumetric-statistical method at 500 mln tons of equivalent hydrocarbons.  相似文献   

11.
《Applied Geochemistry》1998,13(5):581-591
Six sediment cores were taken in sedimentation zones of the Volga river (located in the southern part of the Russian Federation) and, additionally, 6 sediment cores were taken in several lakes (sedimentation zones) in the central and western part of the Danube delta in Romania. Priority pollutants (8 metals, 7 polychlorinated biphenyls and 10 polycyclic aromatic hydrocarbons) were determined in all samples of all cores. Present-day and historical levels of pollutants since the late 1930s were established through the use of radionuclide time tracers (137Cs, 134Cs). For the persistent metals and polycyclic aromatic hydrocarbons, trends in the concentration profiles during the last 5 decades are described. Low and hardly changing concentrations of As, Cu, Zn and all studied PAHs were observed during the last five decades in the sediments of the Volga river. Recently deposited sediments show slightly increasing levels for the heavy metals Zn and Cr and As in the Volga delta. For the studied metals and PAHs, maximum concentrations were found around 1987 in the sediments of the Danube delta. Sediments deposited around 1940 and recently deposited sediments in the Danube delta showed lower pollutant levels. If the contents of heavy metals, PAHs and PCBs in the aquatic sediments in the deltas of the rivers Rhine, Danube and Volga are compared, it is clear that the Volga delta is and was the cleanest delta during the last 5 decades. Nowadays the contents of heavy metals (except Cu and Ni), PAHs and PCBs in the aquatic sediments of the river Rhine are still highest compared to the other two rivers. The recent load of heavy metals (except Cd and Zn) in the sediments of the river Danube is the highest compared to the other two rivers.  相似文献   

12.
This work considers results of the study of Holocene cover sediments of Iceland largely composed of wind-transported palagonitized hyaloclastite particles and coeval horizons of acid and basic tephra. It is established that polyciclic aromatic hydrocarbons (PAH) are released from the basaltic glass in natural environments only in the case of intense physicochemical alteration and destruction of its structure. This process does not influence the composition of polycyclic aromatic hydrocarbons and their quantitative proportions. No new polyclic aromatic hydrocarbons formed during several thousands of years of the Holocene section accumulation. Hydrocarbons are transferred from fixed the state in basaltic glass into the free state in palagonites practically without any changes. Polyciclic aromatic hydrocarbons were mainly redeposited by winds, derived together with palagonite from weathered hyaloclastites, and precipitated from atmosphere with tephra during eruptions.  相似文献   

13.
The biodegradability of polycyclic aromatic hydrocarbons such as naphthalene, fluorene, anthracene and phenanthrene by a halotolerant bacterial consortium isolated from marine environment was investigated. The polycyclic aromatic hydrocarbons degrading bacterial consortium was enriched from mixture saline water samples collected from Chennai (Port of Chennai, salt pan), India. The consortium potently degraded polycyclic aromatic hydrocarbons (> 95%) at 30g/L of sodium chloride concentration in 4 days. The consortium was able to degrade 39 to 45% of different polycyclic hydrocarbons at 60 g/L NaCl concentration. Due to increase in salinity, the percent degradation decreased. To enhance polycyclic aromatic hydrocarbons degradation, yeast extract was added as an additional substrate at 60g/L NaCl concentration. After the addition of yeast extract, the consortium degraded > 74 % of polycyclic aromatic hydrocarbons at 60 g/L NaCl concentration in 4 days. The consortium was also able to degrade PAHs at different concentrations (5, 10, 20, 50 and 100 ppm) with 30 g/L of NaCl concentration. The polycyclic aromatic hydrocarbons degrading halotolerant bacterial consortium consists of three bacterial strains, namely Ochrobactrum sp., Enterobacter cloacae and Stenotrophomonas maltophilia.  相似文献   

14.
Acta Geochimica - To identify the possible sources and formation mechanism of perylene in sediments, temporal trends of perylene and other polycyclic aromatic hydrocarbons, as well as the organic...  相似文献   

15.
Soils and recent marine sediments contain a complex polycyclic aromatic hydrocarbon assemblage. The many series of alkylhomologs have a similar molecular weight distribution, and it varies little over a wide range of depositional environments. It is suggested that these hydrocarbons are formed in natural fires, are dispersed and mixed by air transport and eventually deposited into surface sediments. The analytical, geochemical and environmental implications of these findings are discussed.  相似文献   

16.
The existence of polycyclic aromatic hydrocarbons in the various environments has aroused great environmental concerns due to their potential hazards to human health. The presence of polycyclic aromatic hydrocarbons in aquifer is particularly sensitive where groundwater is used as a source of potable water. Anaerobic biodegradation of polycyclic aromatic hydrocarbons is an attractive option for remediation of contaminated aquifer sediment. Bacterial and archaeal community structures of phenanthrene-degrading aquifer sediment under methanogenic condition were investigated using clone library analysis in combination with microcosm study. The bacterial members were all affiliated with ??-Proteobacteria. Phylum Euryarchaeota was the predominant archaeal group, represented by genera Methanosarcina, Methanobacterium and Thermogymnomonas. Both bacteria (genera Citrobacter and Pseudomonas) and archaea (genus Methanosarcina) might have links to phenanthrene degradation process. This work might provide some new insights into developing strategies for the isolation of the putative polycyclic aromatic hydrocarbons degraders under methanogenic condition and bioremediating polycyclic aromatic hydrocarbons in leachate-contaminated aquifer sediment.  相似文献   

17.
An investigation for the analysis of polycyclic aromatic hydrocarbons in airborne particulates using thermal desorption and gas chromatography-mass spectrometry is described. Samples are obtained from ambient air using fibreglass filters and the volatile material from the filter is thermally desorbed to gas chromatograph. A 30 meter capillary column is used to separate the hydrocarbons and eight polyaromatic hydrocarbons are used to test the method and recovery is >95%. The eight polycyclic aromatic hydrocarbons anthracene, phenanthrene, fluoranthrene, pyrene, benzo (a) anthracene, chrysene, benzo (a) pyrene and benzo (e) pyrene were the most abundant PAHs found in the samples of ambient air with current method at Uxbridge-London. Application of the measurement of polycyclic aromatic hydrocarbons in ambient air samples shows that the hydrocarbons trapped in the particle phase to a lesser degree at higher ambient temperature. In conclusion a method has been developed to transfer the PAHs in particle phase from a filter to GC-MS by thermal desorption. A standard mixture of PAHs, when absorbed onto the filter, did lead to strong analyte absorbent interactions by the high percent recovery of the sample.  相似文献   

18.
Mercury distribution was examined in the sediments of Lake Baikal that were sampled within the scope of the Baikal Drilling International Project in 1996–1999. The Hg concentrations in the ancient sediments are close to those in the modern sediments with the exception of a few peak values, whose ages coincide with those of active volcanism in adjacent areas. Mercury was demonstrated to be contained in the sediments in the adsorbed Hg0 mode, predominantly in relation with organic matter. When the organic matter of the bottom sediments is decomposed in the course of lithification, Hg is retained in the sediments adsorbed on the residual organic matter, and the concentration of this element corresponds to its initial content in the bottom sediments during their accumulation. Mercury concentrations in lithologically distinct bottom sediments of Lake Baikal and its sediments as a whole depend on the climate. Sediments that were formed during warm periods of time contain more Hg than those produced during cold periods or glaciation. Periodical variations in the Hg concentrations in the bottom sediments of Lake Baikal reflect the variations in the contents of this element in the Earth’s atmosphere in the Late Cenozoic, which were, in turn, controlled by the climatic variations on the planet and, thus, can be used for detailed reconstructions of variations in the average global temperature near the planet’s surface.  相似文献   

19.
A solvent–water extraction method was proposed as an assessment tool to estimate the bioavailability of polycyclic aromatic hydrocarbons in coal–tar-contaminated soils. The approach taken was to measure the percent of polycyclic aromatic hydrocarbons extracted by a solvent–water mixture and comparing the results with the percent of polycyclic aromatic hydrocarbons degraded in a soil slurry reactor. Five soil samples from three former manufactured gas plant sites and a coal–tar disposal site which were operated between 1880 and 1947, and 1945 and 1950, respectively, in Iowa, USA were used in this study. Extraction experiments were conducted using acetone–water or ethanol–water mixtures with solvent volume fractions ranging from 1.0 to 0.4 (v/v). The percent of polycyclic aromatic hydrocarbons extracted from the various soils decreased as the volume fraction of the solvent in the solvent–water mixture was reduced. An acetone–water mixture of 0.6 was found to be appropriate in correlating the percent of polycyclic aromatic hydrocarbons degraded to the percent of polycyclic aromatic hydrocarbons extracted. For the first correlation, the percent extracted and the percent biodegraded were modified by using the molecular weights and log K ow of polycyclic aromatic hydrocarbons, respectively. For the second correlation, the equation relating the percent extracted and the percent biodegraded was modified using soil properties such as organic carbon content and percent of clay and silt. Although the experiments were conducted for a limited number of soils, the extraction method appeared to be a good starting point in estimating the bioavailability of polycyclic aromatic hydrocarbons in coal–tar-contaminated soils.  相似文献   

20.
Heavy contaminant load released into the Northern Dvina River during flooding increased the concentrations of aliphatic (AHC) and polcyclic aromatic (PAH) hydrocarbons in water and bottom sediments. The composition of hydrocarbons was different from that of the summer low flow season. The concentrations of dissolved and particulate AHC ranged from 12 to 106 and from 192 to 599 μg/l, respectively, and bottom sediments contained from 26.2 to 329 μg/g AHC and 4 to 1785 ng/g PAH. As the transformation of AHC occurred at low spring temperatures, the alkane composition was shown to be dominated by terrigenous compounds, whereas more stable PAH showed elevated contents of petrogenic and pyrogenic compounds. It was also shown that the Northern Dvina-Dvina Bay geochemical barrier prevents contaminant input into the White Sea, i.e., acts as a marginal filter.  相似文献   

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