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1.
大辽河水系表层水中多环芳烃的污染特征   总被引:8,自引:0,他引:8  
采用GC/MS对大辽河水系的浑河、太子河和大辽河表层水和悬浮物中的多环芳烃 (PAHs) 进行了定量分析,探讨了大辽河水系表层水和悬浮物中多环芳烃分布特征与来源.结果表明,水样和悬浮颗粒物中PAHs总量浓度分布范围分别为:水样946.1~13 448.5 ng·L-1;悬浮颗粒物317.5~238 518.7 ng·g-1.多环芳烃的浓度分布表现为太子河>大辽河>浑河,靠近工业区的PAHs浓度明显高于城市和非工业区.水样中PAHs以3~5环为主,悬浮颗粒物样中PAHs以2环为主.PAHs特定分子比率分析表明,大辽河水系受到石油输入和热解的复合PAH污染,采样站位附近石油化工和钢铁工业是PAHs的主要来源.与世界其他河流和海洋地区相比,水和悬浮颗粒物中污染浓度较高,具有一定的生态风险.  相似文献   

2.
This study was conducted to investigate the occurrence, distribution, and source of 16 polycyclic aromatic hydrocarbons (PAHs) in the Hanjiang River Basin and the Danjiangkou (DJK) Reservoir. The concentrations of total PAHs in surface water, sediments, and bank soils ranged from 9.42 to 137.94 ng/l, 86.23 to 2514.93 ng/g, and 133.17 to 671.93 ng/g dry weight, respectively. The composition pattern of PAHs showed that 3-ring PAHs were dominated in all of the samples, while the proportion of high molecular weight PAHs (5- to 6-ring PAHs) in sediments and bank soil samples was almost three times higher than water. The source apportionment analysis showed that most of the PAHs in water were derived from sources of petroleum and combustion, while combustion was the predominant source of PAHs in sediments and bank soils. The methods based on toxic equivalency factors, risk quotient, and incremental lifetime cancer risk were used to assess the ecosystem risk and potential health risk of PAHs. The risk assessments showed that PAHs in the DJK Reservoir were out of potential health risk, but the ecological risk for majority of 16 PAHs was in the moderate level.  相似文献   

3.
DNA in its native and denatured form and yeast RNA complex individual aromatic hydrocarbon molecules but single-stranded poly A does not. The degree of complexing appears to depend on molecular dimensions; it is appreciable for phenanthrene, pyrene, and benzpyrene but very small or undetectible for coronene, tetracene, pentacene, and 20-methylcholanthrene.  相似文献   

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In this research, ecological risks for eight individual polycyclic aromatic hydrocarbons (PAHs) and ∑PAH8 in surface sediments from middle and lower reaches of Yellow River are evaluated using overlapping areas of probability density curves and margin of safety (MOS), based on the toxicity data and the exposure concentrations of PAHs in sediments collected from 23 sites. In the overlapping areas of probability density curves, the risk of Ant and Pyr are the highest, then the risk level is in the order of Flua > Nap > Phe > BaP > Flu > Ace. The values of MOS10 present that Pyr (4.62 × 10?4), Ant (5.60 × 10?3), and Flua (6.4 × 10?3) have a significantly high ecological risk level, while Nap and Phe have middle-level ecological risk. As for Ace, BaP, and Flu, they pose limited risk to the ecological system with MOS10 greater than 1.0. The ∑PAH8 (2.66 × 10?5) is a higher risk level than that of any individual PAHs, where the probabilities of ∑PAH8 in excess of the 10th percentile of the toxicity data were 86%.  相似文献   

7.
Amur sturgeon Acipenser schrenckiii Brandt 1869 and kaluga Huso dauricus (Georgi 1775) are critically endangered species with populations showing significant decline from historical levels due to overexploitation, yet little is known about their population structure. Adults are not often captured in the Fuyuan reach of the Amur River, Heilongjiang Province, Northeast China, and the government prioritizes juvenile sturgeon management. This study was conducted to determine the age and length/weight relationships of juvenile Amur sturgeon and kaluga in the Fuyuan reach of the Amur River. We estimated age using pectoral fin spine sections obtained from 65 juvenile Amur sturgeon and 50 juvenile kaluga. We compared the age estimates from two readers, and found 100% between‐reader agreement in 67.7% of the Amur sturgeon and 64.0% of the kaluga. The majority of differences in estimated age were within 1 year. Length/weight relationships (LWR) were calculated, and the LWR of the Amur sturgeon and kaluga were W = 0.0025L3.106 (r2 = 0.966)and W = 0.0022L3.175 (r2 = 0.989), respectively. Our study provides the age structure and LWR in juveniles of two sturgeon species.  相似文献   

8.
Diffuse pollution with polycyclic aromatic hydrocarbons (PAHs) of topsoil in urban regions has caused increasing concerns in recent years. We simulated diffuse pollution of soil in microcosms by spiking sandy topsoil (A-horizon) and coarse, mineral subsoil (C-horizon) with street dust (PM63) isolated from municipal street sweepings from central Copenhagen. The microbial communities adapted to PAH degradation in microcosms spiked with street dust in both A-horizon and C-horizon soils, in spite of low PAH-concentrations. The increased potential for PAH degradation was demonstrated on several levels: by slowly diminishing PAH-concentrations, increased mineralization of 14C-PAHs, increasing numbers of PAH degraders and increased prevalence of nah and pdo1 PAH degradation genes, i.e. the microbial communities quickly adapted to PAH degradation. Three- and 4-ring PAHs from the street dust were biodegraded to some extent (10-20%), but 5- and 6-ring PAHs were not biodegraded in spite of frequent soil mixing and high PAH degradation potentials. In addition to biodegradation, leaching of 2-, 3- and 4-ring PAHs from the A-horizon to the C-horizon seems to reduce PAH-levels in surface soil. Over time, levels of 2-, 3- and 4-ring PAHs in surface soil may reach equilibrium between input and the combination of biodegradation and leaching. However, levels of the environmentally critical 5- and 6-ring PAHs will probably continue to rise. We presume that sorption to black carbon particles is responsible for the persistence and low bioaccessibility of 5- and 6-ring PAHs in diffusely polluted soil.  相似文献   

9.
The pollution of the Amur water with organic compounds at the Khabarovsk water-supply point has been analyzed by means of gas chromatography-mass spectrometry (GC-MS). Among environmental pollutants, petroleum hydrocarbons and alkylphtalates predominate. A number of potentially dangerous compounds present in the waste water of the rubber industry works and some other dangerous compounds including a herbicide of TsP 32179 type were detected. Pollution with these compounds has a stable character. The concentrations of a number of critical substances did not exceed the MPCs; however, many compounds are toxic micro-impurities. A great part of the identified compounds are of microbiological origin.  相似文献   

10.
Polycyclic aromatic hydrocarbons in the diet.   总被引:23,自引:0,他引:23  
D H Phillips 《Mutation research》1999,443(1-2):139-147
Polycyclic aromatic hydrocarbons (PAHs), of which benzo[a]pyrene is the most commonly studied and measured, are formed by the incomplete combustion of organic matter. They are widely distributed in the environment and human exposure to them is unavoidable. A number of them, such as benzo[a]pyrene, are carcinogenic and mutagenic, and they are widely believed to make a substantial contribution to the overall burden of cancer in humans. Their presence in the environment is reflected in their presence at detectable levels in many types of uncooked food. In addition, cooking processes can generate PAHs in food. PAHs can also be formed during the curing and processing of raw food prior to cooking. Several studies have been carried out to determine the levels of exposure to PAHs from representative human diets, and the proportion of the overall burden of environmental exposure to PAHs that is attributable to the diet. In most cases, it is concluded that diet is the major source of human exposure to PAHs. The major dietary sources of PAHs are cereals and vegetables, rather than meat, except where there is high consumption of meat cooked over an open flame. More recently, biomonitoring procedures have been developed to assess human exposure to PAHs and these have also indicated that diet is a major source of exposure. Exposure to nitro-PAHs through food consumption appears to be very low.  相似文献   

11.
The thermodynamics of transfer of aromatic (benzene, toluene) and aliphatic (ethane, propane, butane) hydrocarbons from the gas phase into water in the temperature range 5–125°C have been analyzed in order to determine the net hydration effect of these compounds. In the case of the aromatic hydrocarbons the enthalpic contribution predominates over the entropic contribution to the Gibbs energy of hydration. This results in a negative value of the hydration Gibbs energy of aromatic hydrocarbons, in contrast to the positive Gibbs energy of hydration of aliphatic hydrocarbons. The different sign of the hydration Gibbs energies indicates that the mechanism causing hydrophobicity of aromatic hydrocarbons has different nature than that causing the hydrophobicity of aliphatic hydrocarbons. The comparison of hydration of aliphatic and aromatic hydrocarbons leads to the following thermodynamic parameters for these additional interactions between the benzene ring and water at 25°C: enthalpy −5.4 kJ/mol, entropy 26.8 J/K mol and Gibbs energy −13.4 kJ/mol. The large enthalpic contribution to the Gibbs energy of hydration of aromatic hydrocarbons probably comes from the ability of the aromatic ring to accept hydrogens from water, forming hydrogen bonds.  相似文献   

12.
测定了黑龙江抚远江段和虎林江段黑斑狗鱼(Esoxreicherti)线粒体控制区5'端的560bp序列,在12尾黑斑狗鱼序列中未检测到任何变异位点,即所有个体的序列均完全一致,共享同一种单倍型,群体内和群体间的核苷酸多样性均为0.黑龙江黑斑狗鱼线粒体DNA如此贫乏的遗传多样性,一方面可能是黑龙江水系黑斑狗鱼在更新世冰期可能曾遭受过严重的瓶颈效应;另一方面则可能因目前是国内黑斑狗鱼种群数量锐减,种质资源急剧衰退,导致种群遗传多样性的丧失.建议广泛取样调查不同地理种群,并采用AFLP和微卫星等分子标记检测遗传多样性,以确定遗传变异丰富的黑斑狗鱼种群加以保护,促进黑龙江流域黑斑狗鱼资源的有效保护和可持续利用.  相似文献   

13.
In the laboratory experiment and in fish caught in conditionally clean and polluted areas, the presence of metabolites of polycyclic aromatic hydrocarbons in bile by methods of conventional and synchronous spectrofluorimetry was determined. The study showed that this approach is well suited for the detection of metabolites of polycyclic aromatic hydrocarbons with 2–3, 4, and 5–6 aromatic rings. If the content of metabolites of polycyclic aromatic hydrocarbons with 4 and 5–6 rings in bile is low, the method of synchronous spectrofluorimetry is less sensitive than conventional spectrofluorimetry. Both methods of monitoring are simple and fast and reflect the real picture of water pollution.  相似文献   

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Rates of polycyclic aromatic hydrocarbon (PAH) degradation and mineralization were influenced by preexposure to alternate PAHs and a monoaromatic hydrocarbon at relatively high (100 ppm) concentrations in organic-rich aerobic marine sediments. Prior exposure to three PAHs and benzene resulted in enhanced [14C]naphthalene mineralization, while [14C]anthracene mineralization was stimulated only by benzene and anthracene preexposure. Preexposure of sediment slurries to phenanthrene stimulated the initial degradation of anthracene. Prior exposure to naphthalene stimulated the initial degradation of phenanthrene but had no effect on either the initial degradation or mineralization of anthracene. For those compounds which stimulated [14C]anthracene or [14C]naphthalene mineralization, longer preexposures (2 weeks) to alternative aromatic hydrocarbons resulted in an even greater stimulation response. Enrichment with individual PAHs followed by subsequent incubation with one or two PAHs showed no alteration in degradation patterns due to the simultaneous presence of PAHs. The evidence suggests that exposure of marine sediments to a particular PAH or benzene results in the enhanced ability of these sediments to subsequently degrade that PAH as well as certain other PAHs. The enhanced degradation of a particular PAH after sediments have been exposed to it may result from the selection and proliferation of specific microbial populations capable of degrading it. The enhanced degradation of other PAHs after exposure to a single PAH suggests that the populations selected have either broad specificity for PAHs, common pathways of PAH degradation, or both.  相似文献   

16.
太子河水体中多环芳烃分布与污染源解析   总被引:3,自引:0,他引:3  
利用振荡提取-硅胶柱净化-HPLC荧光(FLD)/二级阵列检测器(DAD)检测法测定了太子河水中USEPA16种优控多环芳烃(PAHs)的含量。结果表明,枯水期(4月)、丰水期(7月)和平水期(10月)太子河水中PAHs总浓度分别为454.5~1379.7、1801.6~5868.9和367.0~5794.5ng.L-1,同国内外河流相比,太子河水中PAHs污染较严重,且具有明显的季节分布特征,丰水期PAHs浓度远高于枯水期。丰水期、平水期和枯水期太子河水中均以2~3环PAHs为主,但不同季节代表性PAHs的种类不同。污染来源分析表明,枯水期太子河水中PAHs主要来源于石油污染,丰水期和平水期主要来源于石油源和燃烧源的混合源。  相似文献   

17.
The performed investigations have revealed 21 kinds of pathologies in the embryonal development of amphibia and more than 30 kinds in small mammals in the territories with radiation-chemical environmental pollution. Differences in embryonal mortality and pathologies of embryogenesis have been demonstrated for both the representatives of amphibia and mammals and within one class in the regions with different technogenic load. Embryonàl death and pathologies of embryonal development are considered as important reasons of reproductive losses for different species.  相似文献   

18.
Samples of raw waters from the O?awa River, chlorinated raw water, raw water filtered through activated charcoal and treated and chlorinated water before and after ozonization were examined with the use of the Ames test for potential carcinogenic activity. Positive results were obtained for raw water with Salmonella typhimurium strains TA 98 and TA 1535 and for chlorinated raw water with strain TA 1537.  相似文献   

19.
降解芳烃微生物的多样性   总被引:3,自引:4,他引:3  
芳烃是一类生物异源物质,自然微生物群落利用其对环境的适应性,对这类物质由陌生到适应,微生物群落的遗传背景发生了变化,降解芳烃的微生物呈现出多样性,本文系统介绍了降解芳烃微生物的特性,物种资源,环境适应,遗传背景及演变;介绍了各遗传型物种的功能基因数量,表达及调控方式,指明芳烃环境污染的生物修复主要取决于高效工程构造及代谢过程的控制。  相似文献   

20.
During 1985, a biological monitoring study was conducted in the St. Marys River to determine the availability and source areas of polycyclic aromatic hydrocarbons (PAHs) and the relative importance of water and sediment to tissue contaminant concentrations. Clean unionid mussels (Elliptio complanata) were exposed in cages for three weeks at 14 stations and surficial sediments were obtained at 12 of these. The highest concentrations of total PAHs as well as many individual compounds were found in sediments and mussels from the Algoma Steel Slip above St. Marys Falls and in sediments below the discharge of the Edison Sault Electric Co. Canal. Although concentrations were lower below the Falls, elevated levels persisted downstream along the Ontario shore into Lake George. PAHs were also accumulated by mussels exposed along the Michigan shoreline, but at lower levels than along the Ontario shore. From 23 to 63 percent of the PAHs in sediments and 6 to 27 percent of those in mussels were comprised of compounds with mutagenic and/or carcinogenic properties. The predominance of higher molecular weight PAHs in both sediments and mussels as well as lower molecular weight PAHs and nitrogen- and sulfur-containing PAHs in certain areas, indicates that high temperature combustion of fossil fuels is the major source of PAHs, augmented by localized spills of fossil fuels and coke oven by-products.Mussels contained fewer PAHs (up to 18 vs. 25) at lower concentrations (µg kg-1 vs. mg kg-1) than the associated surficial sediments. Also, mussels suspended at mid-depth in the water column accumulated similar concentrations to those exposed to sediments, indicating that the major exposure pathway is via the water filtered by these organisms, and hence, is due primarily to external industrial inputs.  相似文献   

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