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1.
选择北部湾9个典型采样点,研究了潮间带沉积物中重金属和多氯联苯(PCBs)的分布特征和生态风险.分析结果表明,Hg、As、Cu、Pb、Zn、Cd、Cr等重金属和总PCBs的平均含量分别为0.100、10.00、19.89、45.97、208.65、0.098、17.86 mg.kg-1和1.48!g.kg-1.重金属和PCBs表现出不同的空间变化规律.相关性分析表明,北部湾潮间带的重金属主要来自人为污染;沉积物的粒度参数和有机质含量等性质特征是影响PCBs分布和迁移的重要因素;重金属和PCBs总量之间不存在明显的相关性.生态风险评价结果表明,PCBs和Cd是北部湾潮间带最主要的生态风险因子,Zn和PCBs是优势污染物;研究区域总体处于中等生态风险等级,表明沿岸港口和临海工业等人为活动已经对北部湾滨海地区造成了一定的环境压力.  相似文献   

2.
牡蛎和贻贝中二噁英及多氯联苯同类物的分布   总被引:5,自引:0,他引:5  
利用同位素稀释、高分辨气相色谱-高分辨质谱联用仪,首次测定了大连湾牡蛎和贻贝等海洋生物体内痕量的二噁英和多氯联苯,并比较了二噁英及多氯联苯的同类物在牡蛎和贻贝中的含量分布。结果表明,所采集的牡蛎和贻贝样品中均含有二噁英和多氯联苯,且多氯联苯的含量明显高于二噁英,反映出环境中多氯联苯背景值大于二噁英的背景值。其中,牡蛎和贻贝中二噁英总质量分数平均值分别为47.8pg/g和216pg/g(以干物质计),毒性当量平均值分别为O.89pg/g和0.87pg/g;12种有毒性的共平面多氯联苯的总质量分数平均值分别为585.5pg/g和818.6pg/g,总毒性当量平均值分别为0.47pg/g和1.18pg/g。牡蛎和贻贝样品中的二噁英及多氯联苯的同类物含量分布基本类似,表明二者摄取的二噁英及多氯联苯可能有相似的来源。可以把牡蛎和贻贝作为生物标志物,以监测海洋环境中二噁英和多氯联苯的污染状况。  相似文献   

3.
利用气相色谱-质谱(GC-MS)检测了大辽河表层水中邻苯二甲酸酯类(PAEs)有机污染物的浓度水平,分析其分布特征,并对PAEs类有机污染物的环境健康风险进行了评价。结果表明,大辽河表层水中共检出4种PAEs,其质量浓度范围为n.d.#0.754μg·L~(-1)。4种PAEs类中质量浓度平均值最高的为邻苯二甲酸二异辛酯(DIOP)(0.36μg·L~(-1)),最低的为邻苯二甲酸二甲酯(DMP)(0.01μg·L~(-1))。4种PAEs浓度贡献大小依次为:邻苯二甲酸二异辛酯(DIOP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二甲酯(DMP)。DBP浓度基本符合国家地表水环境质量标准(GB3838—2002)。与国内其他水域相比,大辽河表层水中PAEs的污染程度处于较低水平。DMP和DEP的最高值均出现在营口市区最主要的工业和生活污水排污口之一——纱厂潮沟采样点,DBP和DIOP的最高值则分别出现在牛庄大桥和港监潮沟采样点。总PAEs类有机污染物分布趋势为:在工业分布较多的区域及主城区附近水域PAEs浓度较高,大辽河上游区域PAEs浓度相对较低。利用US EPA健康风险评估模型粗略估算,大辽河表层水中PAEs类污染物的非致癌风险指数值低于1。  相似文献   

4.
可吸入颗粒物(PM10)作为空气中一种重要的介质,对多氯联苯(PCBs)在环境中的迁移扩散起着重要作用.本文对上海市典型化工区大气PM10中的PCBs的污染水平、来源及其气象影响因素进行分析研究,为工业区环境中PCBs的迁移转化过程研究、生态风险评价和工业区综合整治提供基础和依据.  相似文献   

5.
为了解拉萨河中放射性核素238 U和232 Th的污染水平及其对人类的致癌风险,利用拉萨河中下游和堆龙曲支流16个采样点水样的238 U和232 Th含量,采取美国环境保护局(U.S.Environmental Protection Agency,US EPA)推荐的放射性核素健康风险评价方法,评估不同年龄人群因饮水途径摄入核素的致癌风险.结果表明,拉萨河中238U和232Th平均活度浓度分别为(2.62±3.46)×10-2 Bq·L-1和(2.3±0.478)×10-3 Bq·L-1,比我国地表水平均值分别高31%和低61.7%;238U和232Th含量沿程分别呈波动稳定和波动变化的趋势;不同人群平均总致癌风险分别为(4.81±4.61)×10-8(幼儿组)、(2.29±1.81)×10-8(少年组)和(3.08±2.13)×10-8 a-1(成年组),均低于1×10-6 a-1(US EPA标准)和我国地表水平均致癌风险值,但对幼儿的致癌危害最大;238U和232Th的致癌风险贡献率随年龄的增长分别下降和上升;建议对羊八井镇附近河水进行持续监测,确保地热资源开发不会造成拉萨河放射性核素的污染.本研究不仅可以为拉萨河放射性核素污染的研究提供参考,而且可以为拉萨河未来的环境保护提供科学依据.  相似文献   

6.
7.
桑沟湾水体中多氯联苯的时空分布特征   总被引:3,自引:0,他引:3  
气相色谱法分析并结合外标法,定量测定2009年4个航次桑沟湾海域水体中7种多氯联苯类化合物的含量,探讨了多氯联苯污染物在该海域组成以及时空分布特征.结果表明,桑沟湾水体中,多氯联苯的组成主要以低氯取代物为主.该海域多氯联苯含量分布特征呈现为夏季最高,秋春季次之,冬季最低.与其它海域相比,其含量处于中等水平,且低于美国环保局规定的标准值.  相似文献   

8.
石油污染滩涂生物体内TPH分布及健康风险评估   总被引:1,自引:0,他引:1  
通过研究溢油事故污染区域中典型生物体内TPH(Total Petroleum Hydrocarbons)分布特征,对其进行暴露人体健康风险评估,从而为污染区域的生态系统修复与恢复工作提供指导依据。在研究区域受溢油污染并采取应急处置10个月后,采集了位于4个污染滩涂集中填放区和1个不受污染的对照区内的生物体和沉积物样品,采用紫外分光光度法和荧光分光光度法测得 TPH 含量。结果表明,污染区域中无齿螳臂相手蟹 Chiromantes dehaani)肌肉组织中的 TPH 含量分布范围为2.94~39.63 mg·kg-1,内脏中的TPH含量分布范围为8.62~155.41 mg·kg-1,内脏组织中的TPH含量高于肌肉组织,两者呈显著的相关性(Pearson相关系数r=0.9456)。受潮汐水动力等环境因素的影响,整个研究区域生物体内TPH的累积呈现不连续非均质特征。生物体肌肉和内脏组织中的TPH含量与沉积物中TPH含量具有明显的线性关系(y=283.3 x+100,r2=0.9901;y=60.701 x+100,r2=9038),溢油事故造成的沉积物污染是影响生物体内TPH累积的一个重要因素。同时,采用US EPA人体暴露风险评价方法进行人体健康风险评估,结果显示,污染区域生物体内TPH经口摄入的暴露风险指数ERI均值均大于1,分别为1.13、1.05、2.58、2.73,暴露风险处于不可接受水平。根据人体健康风险的可接受水平计算得出可接受的无齿螳臂相手蟹体内TPH安全值为34.4 mg·kg-1,进一步计算得出污染区域沉积物中TPH的修复目标值为2513 mg·kg-1。  相似文献   

9.
为研究焦化厂土壤中多环芳烃(PAHs)的污染特征及其健康风险,以某焦化厂为目标,布设260个点位,根据各点位污染情况,采集不同深度的土壤样品共780件。通过分析样品中18种PAHs含量,探讨了不同判定标准下厂区土壤中PAHs总体污染程度以及不同功能区污染状况特征,同时根据HJ 25.3—2019《建设用地土壤污染风险评估技术导则》对厂区内18种PAHs进行健康风险评价。结果表明:(1)该焦化厂污染水平较高,且厂区污染在空间上表现出强烈非均质性。厂区内PAHs以2~3环为主,占比为58.82%,4~6环PAHs占比为41.48%。厂区内以苯并[a]芘为基准的6种主要风险PAHs的毒性当量浓度(TEQBap)分布特征与总PAHs(∑18PAHs)含量分布具有一致性。(2)不同功能区表层土壤PAHs含量均值从高到低依次为污水处理区>化产区>焦炉区>锅炉发电厂>煤炭储存区>办公区。不同功能区低环与中高环PAHs含量比值不同,表明各区域污染物来源存在差异。(3)厂区内主要健康风险来源于化合物的致癌风险,不同功能区的致癌风险...  相似文献   

10.
为了解东江流域农村土壤多环芳烃的分布特征与人类健康风险,采集了30个不同土地利用类型农村表层土壤样品,进行采用索氏抽提法,硅胶/氧化铝(2:1)层析柱分离纯化,最后加内标经气相色谱-质谱仪定量解析的方法测定16种多环芳烃的含量。同时,测定了土壤中不同形态有机质包括总有机碳(TOC)、非水解性有机碳(NHC)、黑碳(BC)以及无定形有机碳(AOC)的含量。结果表明,土壤多环芳烃质量分数在24-238μg·kg-1之间,平均质量分数为107±60μg·kg-1。在16种多环芳烃中,萘、菲、荧蒽和苯并(b)荧蒽的含量最高,占总多环芳烃含量的比重依次为16%、20%、10%和10%。土壤中多环芳烃含量与TOC、NHC以及BC均具有极显著的线性关系(p〈0.01),三者斜率的大小顺序为BC〉NHC〉TOC(p〈0.01),表明土壤有机碳中的非水解性有机碳和黑碳在控制土壤中多环芳烃的分布、积累中发挥着重要的作用。土壤中多环芳烃含量与AOC的相关性不显著(p=0.29)。另外,健康风险评价表明儿童暴露的增量终身致癌风险(ILCRs)在可接受的安全范围内(ILCRs 〈10-6),而成人暴露的增量终身致癌风险则相对较高(10-6皮肤接触〉呼吸;而成人则为:皮肤接触〉误食土壤〉呼吸。  相似文献   

11.
多氯联苯对我国土壤微生物的生态毒理效应   总被引:1,自引:0,他引:1  
作为持久性有机污染物(POPs),多氯联苯(PCBs)一旦进入土壤将长期存留并对土栖生物产生潜在危害。土壤微生物是土壤生态系统重要组成部分,研究外源PCBs对土壤微生物的生态毒理效应,筛选出指示PCBs污染的敏感指标并获取可靠的生态毒理数据十分重要。研究以江西红壤和天津潮土为供试土壤,在室内25℃连续培养28 d的条件下进行了生态毒理实验,选择了微生物量碳、呼吸强度、代谢熵、硝化作用、脱氢酶活性、脲酶活性和微生物群落功能多样性为微生物指标。结果显示:1)在28 d培养时间内,多氯联苯(PCBs)的毒性作用随培养时间的延长而增强,且在红壤中的毒性作用强于在潮土中,表明PCBs对土壤微生物的毒性作用存在时间效应并受土壤性质的影响。2)各微生物指标的敏感性不同,微生物量碳、脲酶活性和微生物功能多样性对PCBs污染反应不够敏感,而土壤呼吸强度、代谢熵、硝化作用和脱氢酶活性对PCBs污染反应敏感。3)14 d时,红壤中PCBs对脱氢酶活性、呼吸强度和代谢熵的EC10值分别为1.20、3.18和1.09 mg·kg-1,而在潮土中分别为6.31、4.73和50 mg·kg-1;28 d时,红壤中PCBs对硝化作用、脱氢酶活性、呼吸强度和代谢熵的EC10值分别为2.32、0.77、0.51和0.71mg·kg-1,而在潮土中分别为5.91、1.65、3.00和50 mg·kg-1。综合考虑经济和实际需要等因素,建议将呼吸强度、硝化作用和脱氢酶活性作为PCBs污染土壤生态毒理评价中的首选敏感指标,并建议培养时间设置为28 d。  相似文献   

12.
以鲫鱼(Carassius auratus)为试验鱼类,研究其暴露于不同浓度的PCBs(多氯联苯)后鱼肝组织中EROD酶活性和血清性激素含量的动态变化,探讨了2者间的相关性。结果表明,鲫鱼在PCBs中暴露后,其肝脏组织中EROD酶被诱导,酶活性随PCBs浓度增大而增强,呈明显的剂量-效应关系;EROD酶活性随暴露时间延长而上升,10 d后达平衡;鲫鱼血清中睾酮含量随PCBs浓度增大和暴露时间延长呈下降趋势,但雌二醇含量则显著上升,表明PCBs对鱼类具有环境雌激素效应;在一定浓度范围内,EROD酶活性与血清睾酮含量呈负相关,与血清雌二醇含量呈正相关。因此可用鱼肝EROD酶和血清性激素含量的协同变化作为污染生物标志物来评价PCBs的早期污染生态效应。  相似文献   

13.
The distribution and impacts of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) and polychlorinated biphenyls (PCBs) in the Taiwan Er-Jen River were investigated by monitoring fish distribution and measuring PCDD/DFs and PCBs levels in sediment and fish samples. Most of the fish collected are pollution-resistant species such as Oreochromis spp, Liza macrolepsis, Channa spp and Megalops cyprinoides. the most polluted river sections are in the upstream where large amount of waste effluents from households, livestock rearing and nearby dumping sites were discharged into the river, and the lower reaches of the river where metal recovery activities including open burning of waste electrical wire/scrap occurred. Sediment samples collected near the burning site show 2,3,7,8-TCDD toxicity equivalents (TEQ) ranging from 0.014 to 14.2 ng g-1 by PCDD/DFs and from 0.015 to 1.03 ng g-1 by coplanar PCBs (Co-PCBs). the fish samples show TEQ ranging from 0.029 to 0.615 ng g-1 by PCDD/DFs and from 0.012 to 0.12 ng g-1 by Co-PCBs. Possible PCDD/DFs sources are discharged PCBs, open burning of waste wire/scrap, and pentachlorophenol. the consumption of these fish will cause an average intake of 54 pg kg-1 d-1 TEQ. the prevention of direct discharge of livestock and the dumping of waste effuents into River Er-Jen as well as the control of metal recovery activities appears to be the first step toward the restoration of River Er-Jen.  相似文献   

14.
Abstract

The distribution and impacts of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) and polychlorinated biphenyls (PCBs) in the Taiwan Er-Jen River were investigated by monitoring fish distribution and measuring PCDD/DFs and PCBs levels in sediment and fish samples. Most of the fish collected are pollution-resistant species such as Oreochromis spp, Liza macrolepsis, Channa spp and Megalops cyprinoides. the most polluted river sections are in the upstream where large amount of waste effluents from households, livestock rearing and nearby dumping sites were discharged into the river, and the lower reaches of the river where metal recovery activities including open burning of waste electrical wire/scrap occurred. Sediment samples collected near the burning site show 2,3,7,8-TCDD toxicity equivalents (TEQ) ranging from 0.014 to 14.2 ng g?1 by PCDD/DFs and from 0.015 to 1.03 ng g?1 by coplanar PCBs (Co-PCBs). the fish samples show TEQ ranging from 0.029 to 0.615 ng g?1 by PCDD/DFs and from 0.012 to 0.12 ng g?1 by Co-PCBs. Possible PCDD/DFs sources are discharged PCBs, open burning of waste wire/scrap, and pentachlorophenol. the consumption of these fish will cause an average intake of 54 pg kg?1 d?1 TEQ. the prevention of direct discharge of livestock and the dumping of waste effuents into River Er-Jen as well as the control of metal recovery activities appears to be the first step toward the restoration of River Er-Jen.  相似文献   

15.
2011年春季在北部湾沿岸潮间带布设9个站位,采集双壳类动物波纹巴非蛤(Paphia undulata)并测定其软组织中的石油烃(TPH)和多氯联苯(PCBs)含量,研究两种污染物的分布特征、评价其生物质量并对巴非蛤体内残留PCBs可能造成的人体健康风险进行评价.结果表明,各站位TPH和∑PCBs含量范围分别为56.76—199.49μg.g-1和14.19—52.71 ng.g-1(干质量(dw)),就PCBs的组成而言,高氯代PCBs(PCB153、PCB180、PCB194)为优势同族体,所占比重较大.污染指数计算结果显示,除北海西场海域外,各站位的巴非蛤均受到TPH的重度污染,港口区尤为严重;而所有站位的巴非蛤均未受到PCBs污染.健康风险评价结果显示,所有站位的巴非蛤体内PCBs的非致癌风险处于可接受水平(RQ<1),但是,大多数站位的致癌风险指数(0.83×10-6—3.53×10-6)高于可接受的致癌风险低值(1×10-6),而存在一定的潜在致癌风险.  相似文献   

16.
多氯联苯对孔雀鱼卵黄蛋白原的诱导及检测   总被引:3,自引:0,他引:3  
为探讨利用孔雀鱼(Poecilia reticulata)卵黄蛋白原(Vitellogenin,Vtg)作为生物标志物检测环境雌激素的可行性,采用浸浴法分别使用17β-雌二醇(E2)和多氯联苯(PCBs)对雄性孔雀鱼成鱼进行染毒,30d后测定其性腺系数(GSI)和肝指数(LSI),并将鱼体整体匀浆进行常规聚丙烯酰胺凝胶电泳(Native-PAGE)及磷、脂和糖蛋白特异染色分析.结果表明,PCBs对雄性孔雀鱼具有雌激素效应,和E2均可以诱导雄性孔雀鱼体内产生Vtg,但诱导组雄鱼GSI及LSI与对照组比较均无显著性差异(p>0.05).Native-PAGE及磷、脂、糖蛋白特异性分析表明,孔雀鱼Vtg是一种富含磷、脂、糖的蛋白,具有VtgⅠ、VtgⅡ和VtgⅢ等3种形式,其分子量分别为642kDa、541kDa和441kDa.雄性孔雀鱼Vtg可作为环境雌激素监测的有效生物标记物.  相似文献   

17.
Chemical mixtures are an important area of research as individuals are exposed to low doses of persistent chemical agents known as environmental pollutants throughout their life time. Polychlorinated biphenyls (PCBs) and diethyl phthalate (DEP) are ubiquitous environmental pollutants that could be present in the same environmental compartment; hence organisms may get simultaneously exposed to both. Therefore, a study was undertaken to see whether PCB and DEP together show interactive chronic mixture toxicity in male Wistar rats. Healthy male Wistar rats weighing 70–100?g were randomly assigned to four groups of six each. Control rats were fed on normal diet and water ad libitum. Oil control rats were maintained on a normal diet mixed with corn oil. Rats were given Clophen A60 (PCB) and DEP dissolved individually in corn oil mixed with the diet at 50?mg?kg?1 of the diet/day, as well as a mixture in corn oil mixed with the diet both at 50?mg?kg?1 of the diet/day. After 150 days of treatment animals were sacrificed and enzymes and other biochemical parameters in the serum and liver were assessed. Liver weight to body weight ratio showed a significant increase in Clophen A60 and in Clophen A60?+?DEP treated rats. In the DEP, Clophen A60 and Clophen A60?+?DEP treated groups there was significant increase in liver and serum alanine aminotransferase (ALT) and acid phosphatase (ACP) activity. Aspartate aminotransferase (AST) was significantly increased in the liver and serum of DEP treated rats only. Cholesterol levels were significantly increased only in the serum and the liver of DEP treated rats. Triglyceride levels were significantly increased in the serum of treated rats and only in the liver of Clophen A60 and Clophen A60?+?DEP treated rats. Liver glycogen levels were significantly increased in DEP and Clophen A60?+?DEP treated rats. In all treated animals, there was a significant decrease in liver glutathione reductase (GR). Histology of liver showed severe vacuolations, fatty degeneration and loss of hepatic architecture in Clophen A60 and Clophen A60?+?DEP treated rats, whereas in DEP treated rats only loss of hepatic architecture and granular deposits in the hepatocytes was predominant with mild vacuolations of centrilobular and periportal area. It is evident from this study of mixture toxicity of Clophen A60 and DEP that there is no significantly enhanced toxicity due to the interaction of these two compounds. On the other hand, to some extent there is alleviation in toxicity as evidenced by enzyme ACP and AST levels in the liver. The hepatocellular damage and biliary congestion caused by these two compounds, which can be confirmed by significantly increased liver weights and elevated serum and liver enzyme levels as well as histology, was almost the same between individual and mixture treated group.  相似文献   

18.
粗犷的电子垃圾拆解活动已造成当地野生生物多氯联苯(PCBs)严重污染,但PCBs在野生鸟类中的生物累积特征及潜在的毒害作用研究较少。本研究采集了广东省某电子垃圾拆解地翠鸟(Alcedo atthis)及其食物(各种小型鱼类)样品,研究翠鸟对PCBs的累积特征、生物放大效应及毒性风险。翠鸟肌肉中PCBs中值含量为220μg·g~(-1)脂重,比其他报道值高1~3个数量级。计算的生物放大因子(BMF)显示,大部分PCB单体的BMF值都大于1,表明翠鸟对PCBs具有生物放大效应。计算的共面PCBs毒性当量(TEQs)范围为39~23 600 pg·g~(-1)湿重,已经达到或超过了影响某些鸟类生殖或发育障碍的报道值。上述结果表明,电子垃圾拆卸活动已经造成了当地翠鸟PCBs严重污染,PCBs污染物对电子垃圾拆解地翠鸟及其他野生生物的毒性效应尚需进一步研究。  相似文献   

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