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21.
The transgenic Arabidopsis plants carrying a recombinant guinea pig (g) aryl hydrocarbon receptor (AhR)-mediated β-glucuronidase (GUS) reporter gene expression system were generated for assays of polychlorinated biphenyl (PCB) congeners. The selected transgenic Arabidopsis plant XgD2V11-6 exhibited a correlation between uptake of PCB126 and PCB126-induced GUS activity. Also, the plants showed induced GUS activity towards the supplemental indole 3-acetic acid (IAA). Thus, the GUS assay may reflect induction by both endogenous and exogenous AhR ligands. When biosurfactants, MEL-B, produced in the culture of yeast isolated from plants were used for assays of PCB congeners in the transgenic Arabidopsis plants, they showed marked PCB126 dose-dependent and toxic equivalency factor (TEF) dependent GUS activities. The effects of biosurfactants were clearer when the plants were cultivated on soils containing PCB congeners for 7 days as compared with on soils for 3 days as well as in the medium for 3 days. Threfore, it was estimated that biosurfactants form micellae with PCB congeners, which are easily uptaken by the plants in a mode of passive diffusion, transport into the aerial parts and then induce GUS activity.  相似文献   
22.
A thin film coats impervious urban surfaces that can act as a source or sink of organic pollutants to the greater environment. We review recent developments in the understanding of film and film-associated pollutant behavior and incorporate them into an unsteady-state version of the fugacity based Multimedia Urban Model (MUM), focusing on detailed considerations of surface film dynamics. The model is used to explore the conditions under which these atmospherically-derived films act as a temporary source of chemicals to the air and/or storm water. Assuming film growth of 2.1 nm d−1 (Wu et al., 2008a), PCB congeners 28 and 180 reach air-film equilibrium within hours and days, respectively. The model results suggest that the film acts as a temporary sink of chemicals from air during dry and cool weather, as a source to air in warmer weather, and as a source to storm water and soil during rain events. Using the downtown area of the City of Toronto Canada, as a case study, the model estimates that nearly 1 g d−1 of ∑5PCBs are transferred from air to film to storm water.  相似文献   
23.
Environmental site assessment criteria were originally developed by organizations that focused, almost exclusively, on surface, subsurface, and pollution source contamination. Many of the hazards associated with indoor environments and building structures were traditionally not considered when evaluating sources and entities of environmental pollution. Since a large number of building materials are potentially hazardous, careful evaluation is necessary. Until recently, little information on building inspection requirements of environmental problems has been published. Traditionally, asbestos has been the main component of concern. The ever-changing environmental standards have dramatically expanded the scope of building surveys. Indoor environmental concerns, for example, currently include formaldehyde, lead-based paint, polychlorinated biphenyls, radon, and indoor air pollution. Environmental regulations are being expanded and developed that specifically include building structures. These regulatory standards are being triggered by an increased awareness of health effects from indoor exposure, fires, spills, and other accidents that have resulted in injury, death, and financial loss. This article discusses various aspects of assessments for building structures.  相似文献   
24.
Surface sediment samples from 12 sites of the three selected rivers in Daliaohe River watershed (Hunhe River, Taizihe River and Daliaohe River) were analyzed with the objective of establishing sources and hazard of the organochlorinae pesticides (OCPs) and polychlorinated biphenyl (PCBs) in surface sediments. The total concentrations of OCPs varied from 3.06 to 23.24 ng g−1. ∑HCH (α-HCH, β-HCH, δ-HCH, γ-HCH), ∑DDT (p, p′-DDE, p, p′-DDD, o, p′-DDT, p, p′-DDT) and ∑Cyclodiene (Heptachlor, Aldrin, Heptachlor epoxide, Dieldrin, Endrin) ranged from 1.86 to 21.48, 0.5 to 2.81 and 0.56 to 1.53 ng g−1, respectively. Results of OCPs also illustrate that the most dominant pollutants among the OCPs was ∑HCH, and γ-HCH was the most dominant isomer in HCH, which was evidence of recent input of lindane. It possibly came from the runoff of polluted soils and long-scale transportation. Total PCB concentrations ranged between 1.88 and 16.88 ng g−1. The peak concentrations of PCBs were found in sediments from station T5 and D3, which are in the vicinity of industrial areas and ferry, respectively. These data show a moderate level of OCPs and PCBs contaminations compared to that in other countries.  相似文献   
25.
河流沉积物中有机污染物的分析研究进展   总被引:8,自引:2,他引:6  
总结了近年来河流沉积物中有机污染物的研究进展 ,集中评述了国内有关沉积物中多环芳烃、有机氯农药和多氯联苯的分析研究现状 ,包括样品采集、样品前处理和样品分析 ,并对今后河流、湖泊及水库沉积物中污染物的分析工作作了展望  相似文献   
26.
In order to investigate the distribution pattern of individual organochlorine compounds in soil samples collected from the sites (Canary Island – Spain, China, Germany, India, Romania, Russia, Serbia, Swiss, UK) affected by industrial activities to the more remote areas, principal component analysis was performed on the data taken from literature. Loading plots pointed out the strong correlation among the variables. Score plots revealed similar PCB- and OCP-soil patterns for majority of the investigated sites. Nevertheless, the temporal differences of PCB-soil loads have been identified: the late 1990s and early 2000s concentrations are similar to those of the early 1940s, and they are below the levels existed in 1980. The most pronounced PCB concentrations characterized the soil from 1966. For OCPs the influence of sites location on the detected concentration has been revealed: China and India were characterized by comparably higher loads of DDX (DDT and its metabolites) and of HCH-isomers, respectively.  相似文献   
27.
随机采集广州地区非职业PCBs(polychlorinated biphenyls,多氯联苯)暴露单胎孕妇分娩时羊水,分析羊水中PCBs浓度水平;结合孕妇临床资料(年龄、孕周、身体质量指数(body mass index,BMI))以及孕妇居住环境信息等,阐明了广州地区非职业暴露孕妇羊水PCBs蓄积的影响因素。结果表明,∑33PCBs浓度为15.91-324.38 ng·g-1,平均值为114.34±83.52 ng·g-1,中值为84.8 5ng·g-1;其中十氯含量最低,平均浓度为2.66±3.46 ng·g-1,中值为1.47 ng·g-1;六氯PCBs含量最高,平均浓度为28.79±33.84 ng·g-1,中值为17.48 ng·g-1。样本中有31种PCBs同分异构体在孕妇羊水中检出,分别为PCB 8、28、30、49、52、70、74、77、82、87、99、101、105、114、118、126、128、138、153、156、158、166、169、170、179、180、183、187、189、198和209;羊水主要的PCBs暴露以五氯PCBs、六氯PCBs和七氯PCBs为主,主要的同分异构体为PCB 138(4.73%)、179(4.15%)、153(3.92%)、183(3.89%)、166(3.77%)、187(3.74%)以及180(3.67%);暴露水平与美国、西班牙、加拿大等地区相比属于严重水平。统计结果显示,年龄、身体质量指数和孕周与PCBs蓄积有显著性正相关关系;工业区居住的孕妇相与非工业区居住孕妇相比,上述统计结果更为显著。  相似文献   
28.
准确的水生生态风险评价需要可靠的毒性数据,而其获取要求在一定时间范围内,水体中污染物的浓度保持恒定。对疏水性有机污染物进行水体生物毒性测试时,通常采用有机溶剂加标,然而该方式可能因为污染物的挥发和降解、容器壁吸附、生物摄取等问题,水体中污染物浓度持续下降,导致污染物的浓度-效应关系难以明确。近期为了克服这些问题,被动加标用于替代溶剂加标,通过污染物在加标体系中平衡分配来维持精确和恒定的水体浓度,同时还可通过测定加标聚合物中污染物的浓度来监测水体浓度。首先介绍了被动加标方法及其材料选择,讨论了该方法在生态风险评价中的主要应用,包括分配系数的测定、体外细胞测试、体内生物积累及毒性测试,以及沉积物毒性评价等。然后,以测定代表污染物多氯联苯在聚二甲基硅氧烷与水间的分配系数为例,详细说明被动加标的操作流程。最后,讨论了被动加标方法的优缺点,并对其在水生生态风险中的应用前景进行了展望。  相似文献   
29.
昌盛  白云松  涂响  付青  张坤锋  潘杨  王山军  杨光  汪星 《环境科学》2022,43(12):5534-5546
采用气相色谱-质谱法(GC-MS)测定了北江中上游流域地表水和沉积物样品中多环芳烃(PAHs)和多氯联苯(PCBs)类污染物的含量,分析了PAHs和PCBs的污染水平和空间分布,并评估了污染物的健康风险和生态风险.结果表明,16种PAHs单体在所有水样和沉积物样品中均被检出,检出范围分别为41.82~443.04 ng·L-1和59.58~635.73 ng·g-1,北江中上游PAHs的污染水平为中、轻度.水中PAHs以二环芳烃和三环芳烃为主,沉积物中以三环芳烃和四环芳烃为主.在水样中检出了17种PCBs,浓度范围0.81~287.50 ng·L-1,以六氯联苯和七氯联苯为主;沉积物中检出了8种PCBs,含量范围0.13~3.96 ng·g-1,以五氯联苯和七氯联苯为主.整个调查区域内地表水中PAHs和PCBs的终生致癌风险指数小于10-4,处于中、低水平;非致癌风险指数均小于1,不存在非致癌风险.采用风险商值(RQ)法对地表水中污染物进行生态风险评价,研究区域内地表水中PAHs和PCBs生态风险总体处于中低风险水平,个别点位存在重度风险的污染物单体,值得引起重视.采用沉积物质量基准法(SQGs)对沉积物中污染物进行生态风险评估,沉积物中PAHs和PCBs均处于较低的生态风险水平.  相似文献   
30.
采用体外受精技术评价环境污染物 2 ,2’ ,4,4’ 和 3,3’ ,4,4’ 四氯联苯对小白鼠卵母细胞受精能力和 2 细胞胚胎发育的毒性作用 .实验结果表明 :ρ(PCB) =0 .1,1.0 ,10 .0mg/mL的 2 ,2’ ,4,4’ 和 3,3’ ,4,4’ 四氯联苯均显著降低小白鼠卵母细胞的受精能力 ;ρ(PCB) =1.0 ,10 .0mg/mL的 2 ,2’ ,4,4’ 和 3,3’ ,4,4’ 四氯联苯使卵母细胞的退化率和 2 细胞的畸形率显著增加 ;两种四氯联苯对小白鼠卵母细胞体外受精能力、退化率和 2 细胞胚胎的畸形率无统计差异 .表 2参 2 5  相似文献   
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