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1.
运用GC-MS测定黄河口及邻近海域表层沉积物中多环芳烃(PAHs)含量,探讨PAHs的分布、来源及潜在生态风险。结果表明沉积物中多环芳烃总浓度为111.3~204.8 ng/g,平均浓度为115.8 ng/g;PAHs高浓度样点多分布在黄河口西北缘、西南缘和东缘。黄河口南部和中部沉积物中的PAHs主要来源于燃烧源,西北缘沉积物的PAHs则呈现出石油源和燃烧源混合的特征。除局部(Sc11,Sc12和Sc18)沉积物PAHs具高潜在生态风险,大部分沉积物PAHs潜在生态风险为中等。  相似文献   

2.
山东半岛海岸带面临着各类复杂的环境问题,尤其是受到了多环芳烃(PAHs)等持久性有机物的污染,本文研究了整个山东半岛典型海岸带62个站点表层沉积物中PAHs的含量及其分布特征,并对其来源和潜在风险进行解析与评价。研究表明,该地区表层沉积物中16种PAHs总含量为0.06~3191.40 ng/g(平均值262.08 ng/g),与国内外海岸带相比,山东半岛海岸带表层沉积物中PAHs整体污染状况处于较低水平,但个别站点的PAHs含量偏高。运用特征比值法、相关性分析及主成分分析法解析研究区PAHs主要来源为木柴、煤炭、油类的燃烧以及油类泄露的联合作用。采用效应区间低值法(ERL)和中值法(ERM)对PAHs进行生态风险评价,结果表明莱州湾周边所有站点及威海、青岛周边个别站点苊、芴浓度位于ERL值与ERM值之间,但多数站点对生态环境潜在负面效应很小。山东半岛典型海岸带中PAHs对生物的毒副作用尚在安全可控范围内,极少对生态环境产生负面效应。  相似文献   

3.
近年来我国长江河口有关沉积物中多环芳烃(PAHs)污染的研究主要集中在长江口近海及上海主城区滨岸等区域,而长江口航道则鲜有报道。本文在长江口启东—崇明岛航道区域采集表层(0~20 cm)沉积物样品,利用加速溶剂萃取技术提取,用高效液相色谱-荧光检测器对14种PAHs进行测定,研究其分布特征、环境来源和潜在的生态风险。研究结果显示,PAHs在所有沉积物样品中均有不同程度的检出,浓度范围为83.43~5206.97 ng/g,平均值736.95 ng/g。就PAHs单体而言,含量较高的是2~4环污染物,其中菲的含量最高,占各点位PAHs总量的9.04%~24.06%;其次为荧蒽和芘;具有高致癌性的苯并(a)芘在各个点位均能检出,占PAHs总量的0.94%~10.68%。与国内外类似河口和近海海域相比,本研究区PAHs处于中等污染水平。利用比值法解析PAHs的来源,菲/蒽(Phe/Ant)10且荧蒽/芘(Fla/Pyr)≥1的点位占所有采样点位的56.25%,表明区域内PAHs的主要来源是化石燃料的高温燃烧;位于航运码头附近采样点位的PAHs以石油源为主,部分点位呈化石燃料源和石油源混合污染特征。对照风险效应低值(ERL)和风险效应中值(ERM)进行初步风险评价,表明研究区域部分采样点位的PAHs具有潜在的生态风险。  相似文献   

4.
通过对天津海滨浴场南侧潮间带表层沉积物中多环芳烃(PAHs)的定量分析,探讨其分布特征及来源.研究表明,沉积物中∑PAHs含量范围为91.4×10-9~855.4×10-9,从空间上呈现出高潮滩中潮滩低潮滩的分布特征.样品中PAHs二环和三环含量占主导地位,以石油污染输入为主,并混合有化石燃料的不完全燃烧.根据沉积物风险评价标准,萘、芴、菲、蒽超出风险低值,对潮间带生态具有潜在危害,应严格控制PAHs的人为输入,保护潮间带的生态环境.  相似文献   

5.
土壤中的多环芳烃(PAHs)会威胁人类健康和生态环境安全。为掌握北运河流域(北京段)土壤中PAHs的分布特征及其形成机制,采用克里格插值、主成分分析-多元线性回归等多元统计方法,结合同分异构体比值法对该区域表层土壤中16种优控PAHs的质量分数、分布趋势、空间分布特征及其污染来源进行了研究。结果表明:(1)研究区216件土壤样品中16种PAHs均被检出,且主要为高环PAHs(4~6环),总PAHs的质量分数范围在10.5~19 466.5μg/kg,受污染土壤样品占29.63%;(2)表层土壤中的PAHs在东西及南北方向上均呈现出中部高、两端低的趋势,在空间分布上总体表现为北部区域及中部城区含量较高、其他地区相对较低的特征,且由于人为活动影响导致个别点位PAHs富集,存在点源污染或局部污染;(3)PAHs同分异构体比值法及主成分分析法研究表明,研究区内PAHs的来源为以煤/生物质燃烧及交通燃烧为主、石油泄漏等石油化工源为辅的混合源,多元线性回归方法分析后得到2者的贡献率分别为89%和11%。研究结果可为研究区的污染防控、土地质量评价和国土空间规划等工作提供有力支撑。  相似文献   

6.
东海泥质区表层沉积物中多环芳烃的分布特征及物源   总被引:14,自引:0,他引:14  
以 GC/MSD内标法定量测定了东海近岸和远岸泥质沉积区 18个表层沉积物中多环芳烃 (PAHs)的含量,探讨了多环芳烃在这些泥质区的分布特征、影响因素及来源.结果显示 ,近岸泥质区多环芳烃含量普遍较高,介于 180.3~ 424.8 ng/g(干重 )之间;冲绳海槽次之,含量为 211.7 ng/g ;济州岛西南泥质区最低,含量介于 117.1~ 211.7 ng/g之间.东海泥质区多环芳烃的分布主要受控于离物源的远近、沉积物粒度、有机碳含量以及东海环流体系.东海泥质区的多环芳烃主要来源于热成因,大气干湿沉降和河流输入是其进入泥质区的主要途径.东海泥质区多环芳烃的污染程度中等.  相似文献   

7.
以渤海水体中多环芳烃(PAHs)为研究对象,分别于2019年6月(春夏季)、8月(夏季)和11月(秋季)采集渤海海域的表、底层海水样品,利用气相色谱–质谱联用仪分析了水体中15种优控PAHs,并对其污染水平、单体组成、时空分布及来源特征进行了分析。结果表明,6月、8月和11月渤海表层海水15种PAHs的总浓度(∑_(15)PAHs)范围分别为10.1~67.0、3.20~24.2和6.14~21.5 ng/L,均值浓度分别为34.2±16.8、9.75±4.94和16.0±3.96 ng/L,季节性特征表现为6月>11月>8月。从存在形式看,海水溶解相中PAHs主要以低环为主,高环PAHs更易赋存在海水颗粒相中。水平分布上总体表现出近岸高、中部低的分布特征,河流输入是渤海水体中PAHs的主要来源,渤海南部海域受黄河流域河流输入影响污染尤其严重;垂直分布上春秋季节渤海表、底层没有明显的浓度差异,说明在强烈季风影响下水体垂直混合能力增强,而夏季则在中部海域形成PAHs表层浓度高、底层浓度低的现象,推测与夏季渤海中部冷水团和温跃层的出现有关。特征比值和主成分分析结果表明,多环芳烃的污染源没有明显的季节差异,化石燃料和生物质燃烧是渤海水体中PAHs的主要来源。  相似文献   

8.
为探讨新疆开都河流域水不同介质的来源及分布特征,检测了开都河流域水、土壤和表层沉积物样品中20种有机氯农药(OCPs)和16种多环芳烃(PAHs)的含量。结果显示,OCPs和PAHs在水中的含量分别为42.5~62.5ng/L和29.4~454.3ng/L,在土壤中的含量分别为8.8~12.4ng/g和6.6~128.2ng/g,在表层沉积物中的含量分别为6.6~13.7ng/g和20.8~491.0ng/g。空间分布上,开都河中游污染相对严重的土壤对应的周边河流沉积物也具有较高浓度的污染物,这种分布明显受人类活动影响,沿河道上游呈递增趋势,但总体上低于入湖口沉积物中的含量,表明博斯腾湖蓄积了来自周边的污染物。来源分析表明,开都河流域的六六六(HCHs)和滴滴涕(DDTs)主要是历史残留,而入湖口区水体和表层沉积物中新的DDTs,可能与湖泊沉积物被扰动引起的再悬浮释放有关。PAHs以低分子量组分为主,其高含量主要来自于木柴、煤等中低温燃烧。风险评价结果表明,开都河流域土壤和沉积物中的OCPs和PAHs不存在显著的生态风险。  相似文献   

9.
近些年,随着我国城市化进程不断加快,土壤中多环芳烃污染已经成为威胁土壤环境质量和人体健康的主要因素。文章采集了北京市通州某改造区15件表层土壤(0~20 cm)样品,利用GC-MS分析技术,研究了土壤中美国环境保护署(USEPA)优控的16种多环芳烃(PAHs)的含量及组分特征,根据多环芳烃的空间分布特征和特定成分之间的浓度比值结合多元统计法分析了其污染来源,初步评价了其污染水平,并进行健康风险评价。结果表明:表层土壤中16种多环芳烃含量范围为6.57~8 307.2 μg/kg,均值为1 004.08 μg/kg。多环芳烃组分特征及Fla与(Fla+Pyr)、BaA与(BaA+Chr)的相对质量比值特征显示改造区是燃煤和汽车尾气混合型来源;多元统计后发现石油烃类污染源和化石燃料燃烧源是两种主要成分。最后参照《污染场地风险评估技术导则(HJ 25.3—2014)》对土壤中PAHs进行了健康风险评价,除苯并(a)芘(BaP)致癌风险值略偏高不可接受外,其余致癌与非致癌风险值均可接受。  相似文献   

10.
沉积物中的重金属属于持久性污染物,具有富集性、难降解性和毒性,长时间累积会对生态环境和人体健康造成威胁。为研究珍珠湾红树林湿地表层沉积物中的重金属含量分布特征及质量现状,2021年9月在珍珠湾红树林分布区采集13件表层沉积物样品,分析测试重金属含量。结果表明: 与国内其他红树林湿地相比,珍珠湾红树林湿地表层沉积物中的重金属含量处于相对较低水平; 地累积指数法显示大部分表层沉积物样品无重金属污染,仅有2个站位受到Cd和Hg的轻微污染,潜在生态风险指数法表明湾内各站位均为低生态风险; 相关性分析和主成分分析表明,Cd主要受江平江输入和珍珠湾东南部海水养殖的影响,其他元素主要为自然背景的岩石风化沉积,利用主成分-多元线性回归模型对重金属的来源进行解析认为,表明江平江输入的重金属贡献率为57%,海水养殖影响的重金属贡献率为43%。综上所述,珍珠湾红树林湿地整体生态状况良好,但仍需重点关注Cd的输入。  相似文献   

11.
Concentration, distribution, and sources of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in surface sediments of Laizhou Bay, China. Total PAH concentrations ranged from 97.2 to 204.8 ng/g, with a mean of 148.4 ng/g. High concentrations of PAHs were found in the fine-grained sediments on both sides of the Yellow River estuary (YRE). In contrast, low levels of PAHs were observed in relatively coarse grain sediments, suggesting hydrodynamics influence the accumulation of sedimentary PAHs. The YRE and its adjacent area is the main sink for Yellow River-derived PAHs. Both PAH isomer ratios and principal component analysis (PCA) with multivariate linear regression (MLR) were applied to apportion sources of PAHs. Results indicated that both pyrogenic and petrogenic PAH sources were important. Further PCA/MLR analysis showed that the contributions of coal combustion, petroleum combustion and a combined source of spilled oil and biomass burning were 41, 15 and 44%, respectively. From an ecotoxicological viewpoint, the studied area appears to have low levels of PAH pollution.  相似文献   

12.
松花江底积物中多环芳烃生态风险评价   总被引:4,自引:0,他引:4       下载免费PDF全文
对松花江底积物中16种多环芳烃类化合物(PAHs)进行调查结果显示,松花江底积物中属于美国EPA优先控制的16种PAHs全被检出。16种PAHs总含量范围226.86~10079.68 ng.g-1,平均含量为2230.04 ng.g-1。其中,4环和5~6环PAHs的相对丰度为61.6%,2~3环PAHs的相对丰度为38.4%,研究表明松花江底积物中PAHs主要来源于生物化石燃料燃烧,仅支流嫩江齐齐哈尔下游段、干流肇源县西段主要体现为石油类输入。就松花江PAHs生态风险而言:在第二松花江吉林市上游、吉林市下游段,PAHs遍及低环、中环、高环都超过了生态效应警戒值低值(ERL);嫩江支流泰来东南段PAHs组分萘(Nap)、苊(Ace)、芴(Fl),松花江干流巴彦段二苯并[a,h]蒽(DBA)也超过了生态效应警戒值低值(ERL)。这说明这些超ERL值的河段底积物中PAHs对裸露生物体的毒副作用风险率大于10%,具有一定的潜在生态风险。  相似文献   

13.
Concentrations, spatial distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) listed by the United States Environmental Protection Agency as priority pollutants were investigated in surface sediments of Bohai Bay, North China. Total concentrations of PAHs were in the range of 140.6–300.7 ng/g (dry wt), with an average of 188.0 ng/g. The three predominant PAHs were phenanthrene, acenaphthene and naphthalene. Sedimentary PAH concentrations of the north and central Bohai Bay were higher than those of the southern side of this bay. PAHs source analysis suggested that PAHs in most of the sediments were mainly from grass, wood and coal incomplete combustion. At other stations near the estuaries (Luanhe River Estuary and Chaohe River Estuary) or the oil drilling platform, both petrogenic and pyrogenic inputs were significant. The pyrogenic PAHs close to the oil drilling platform were mainly from petroleum combustion.  相似文献   

14.
Oyster and sediment samples collected from six sites in Galveston Bay from 1986 to 1998 were analyzed for polynuclear aromatic hydrocarbons (PAHs). Total concentrations of parent PAHs in oysters ranged from 20 ng g−1 at one site to 9,242 ng g−1 at another and varied randomly with no clear trend over the 13 year period at any site. Concentrations of alkylated PAHs, which are indications of petroleum contamination, varied from 20 to 80,000 ng g−1 in oysters and were in higher abundance than the parent PAHs, indicating that one source of the PAH contaminants in Galveston Bay was petroleum and petroleum products. Four to six ring parent PAHs, which are indicative of combustion source , were higher than those of 2–3 ring parent PAHs, suggesting incomplete combustion generated PAHs was another source of PAHs into Galveston Bay. Concentrations of parent PAHs in sediments ranged from 57 to 670 ng g−1 and were much lower than those in oysters. Sediments from one site had a high PAH concentration of 5,800 ng g−1. Comparison of the compositions and concentrations of PAHs between sediment and oysters suggests that oysters preferentially bioaccumulate four to six ring PAHs. PAH composition in sediments suggests that the sources of PAH pollution in Galveston Bay were predominantly pyrogenic, while petroleum related PAHs were secondary contributions into the Bay.  相似文献   

15.
Karst areas have much higher ecological vulnerability and are easy to be contaminated by polycyclic aromatic hydrocarbons (PAHs), which are introduced as health risk pollutants. PAHs ratios were used to understand the sources and transport behavior of PAHs conducted in the karst Nanshan Underground River, China. Water, sediments from the underground river and water, sediments, soil from the surface were collected monthly in 2011 and 2012. Abundant PAHs were found both in the underground river and in the surface system. The detected ΣPAHs concentrations varied from 353 to 13,203 ng L?1 in the groundwaters and content from 169 to 12,038 ng g?1 in the sediments of the underground river. The ratios of anthracene to anthracene, plus phenanthrene and fluoranthene to fluoranthene, plus pyrene indicated that PAHs were delivered in the groundwaters from combusted grass, wood, and coal, while in the sediments were a mixture of non-combusted petroleum, grass, wood, coal and combusted grass, wood, coal. The similarities in sources between an underground river and surface system indicated that farmlands play a major role for the transport of PAHs and contamination in the underground river. Karst features are liable for the transport behavior.  相似文献   

16.
Sediments are considered as suitable matrices to study the contamination levels of aquatic environment since they represent a sink for multiple contaminant sources. In this study, the influence of sediment characteristics on the distribution of polycyclic aromatic hydrocarbons (PAHs) and its potential risk in euryhaline, freshwater and humic aquatic bodies of Douglas/Stubbs creek, Ikpa River and Eniong River, respectively, were investigated. The level of PAHs in sediment was quantified using GC–MS, while sediment properties including total organic carbon (TOC) content and grain size were determined by the wet oxidation and hydrometer methods, respectively. The results revealed that the total levels of PAHs in sediment varied significantly between the euryhaline, freshwater and humic freshwater ecosystems. In Ikpa River freshwater ecosystem, a total PAHs load of 1055.2 ng/g was recorded with the suites concentration ranging from 13.0 ng/g (for acenaphthylene) to 161 ng/g (for pyrene). The humic ecosystem of Eniong River had a total PAH load of 11.06 ng/g, while the suites level recorded ranged from 0.04 ng/g for acenaphthene to 2.65 ng/g for chrysene. The total level of PAHs detected in the euryhaline Douglas/Stubbs creek was 14.47 ng/g, and suite concentrations varied between 4.27 ng/g for naphthalene and 5.13 ng/g for acenaphthylene. This shows variation in quantity and quality of PAH contaminants with the nature of ecosystems. It implies complex and diverse contamination sources as well as different capabilities to recover from PAH contamination. Correlation analysis has shown that sediment particle and TOC content influenced PAHs burden in bottom sediments, but the effects varied with the molecular weight of PAHs and the nature of the ecosystems. The TOC was the most significant determinant of PAHs load and distribution in sediment of the freshwater Ikpa River and euryhaline Douglas/Stubbs but had little or no influence in the humic sediment of Eniong River, while the influence of particle size was generally indefinite but slightly associated with PAHs accumulation in the euryhaline sediment. Generally, the total PAH levels (11.0–1055.2 ng/g) recorded were low and below the allowable limit for aquatic sediments. The ecological risk assessment revealed that these levels were lower than the effects range low and effects range medium values. This indicates no acute adverse biological effect although the accumulation of PAHs in freshwater ecosystem of Ikpa River may pose ecological risks as most of the carcinogenic PAH suites had relatively high pollution indices compared to other ecosystem types studied.  相似文献   

17.
为了解大亚湾表层沉积物中重金属的污染状况,对大亚湾海域23个点位表层沉积物中7种重金属元素(Cr、Ni、Cu、Pb、Zn、Cd、As)的质量分数、形态特征、来源控制因素以及潜在生态风险进行了研究。采用优化BCR提取法分析重金属元素赋存形态,并依据各种重金属元素的形态特征与沉积物基质属性进行了相关因子分析,了解其分布的控制因素。结果表明:大亚湾沉积物重金属元素呈现环带状分布特征,从岸向湾内逐渐减小;重金属元素质量分数的高值区主要分布于大鹏澳、哑铃湾及范和港附近;重金属元素赋存形态中Cr、Ni、Cu、Zn、As主要以残渣态存在,Pb主要以可还原态存在,Cd主要以酸提取态存在;7种重金属元素各自非残渣态所占比率从大到小为Pb(78.83%)、Cd(78.65%)、Cu(48.54%)、Zn(48.10%)、Ni(38.31%)、Cr(28.43%)、As(27.76%),即Pb最高,As最低,表明Pb的迁移性最强;通过因子分析,大亚湾重金属主要为沿岸自然风化产物的输入,其次为工业废水及养殖污水。运用酸提取态风险评估法对重金属元素潜在生态风险进行评价,发现研究区所选重金属元素综合风险评价Cd为高风险,其余重金属为中-低风险等级。  相似文献   

18.
《Organic Geochemistry》1999,30(8):937-945
The anaerobic degradation of the polycyclic aromatic hydrocarbons (PAHs) naphthalene and phenanthrene was investigated in several marine harbor sediments. In sediments from Boston Harbor that were heavily contaminated with petroleum, [14C]-naphthalene and [14C]-phenanthrene were oxidized to 14CO2 without a lag, suggesting that the microbial community was adapted for anaerobic PAH oxidation in situ. The addition of molybdate, a specific inhibitor of sulfate-reducing microorganisms, inhibited PAH mineralization which suggested that sulfate reducers were involved in the anaerobic oxidation of the PAHs. PAHs were also anaerobically oxidized at another site in Boston Harbor that was less heavily contaminated, but at a slower rate than in the most heavily contaminated sediments. Sediments not contaminated with petroleum did not significantly oxidize the PAHs. A similar correspondence between rates of anaerobic PAH oxidation and the degree of PAH contamination was observed in sediments from Tampa Bay and San Diego Bay. When relatively pristine sediments from San Diego Bay that did not have a significant capacity for anaerobic PAH oxidation were exposed to high concentrations of naphthalene, they developed a potential for naphthalene degradation that was comparable to that in sediments that had a history of PAH contamination. The increase in potential for naphthalene degradation in the sediments exposed to naphthalene was associated with an increase in naphthalene-degrading microorganisms. These results suggest that many marine harbor sediments contain microorganisms capable of anaerobically oxidizing PAHs under sulfate-reducing conditions and that these microorganisms will respond with an increase in their activity when PAHs are introduced into the sediments. Thus, if PAH inputs into harbor sediments from petroleum can be reduced there may be a widespread potential for microorganisms to remove this PAH contamination from the sediments, despite anaerobic conditions.  相似文献   

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