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1.
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   
2.
类二噁英多氯联苯生殖毒性的研究进展   总被引:1,自引:0,他引:1  
类二噁英多氯联苯(DlPCBs)作为典型的环境内分泌干扰物,会干扰接触个体或其后代的内分泌功能,破坏机体的神经系统、免疫系统,尤其对生殖系统的影响最为明显,比如对生殖器官的形态与功能、生殖内分泌、原始生殖细胞及其受精和早期胚胎发育等产生严重影响,最终导致各种生殖系统疾病的发生。DlPCBs的蓄积性及半挥发性使其在环境中分布广泛,半衰期长的特点使其将对动物及人类的生存和健康造成难以想象的影响。本文综述了DlPCBs的分类与构成、一般性质、生殖毒性以及其可能的致病机理,并对DlPCBs生殖毒性机理研究的重点方向进行了展望。  相似文献   
3.
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   
4.
王江涛  谭丽菊  张文浩  连子如 《环境科学》2010,31(11):2713-2722
利用气相色谱/质谱方法对青岛近海表层沉积物中多环芳烃(PAHs)、多氯联苯(PCBs)和有机氯农药(OCPs)进行了测定,并分析了PAHs、PCBs和OCPs的分布特征.结果表明,PAHs、PCBs和OCPs的均值分别为684.80、6.87和13.52ng·g-1,含量变化均呈近岸高、远岸低的分布规律.燃料的高温燃烧排放对本研究海域沉积物中PAHs有较大贡献;PCBs主要来源于工业及生活排放,但已受到控制;沉积物中HCHs存在工业和农业双重污染源输入,DDT主要是由于历史上使用农药造成,且在表层沉积物中受到好氧微生物降解.与国内外同类研究结果相比,调查海域沉积物中PAHs、PCBs和OCPs的污染程度及生态风险均处于较低水平.  相似文献   
5.

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) residue levels were determined in 53 unhatched eggs from greater roseus flamingos (Phoenicopterus ruber). Eggs were collected in 1996 from the National Park of Doñana (Guadalquivir marshes, Southwest Spain), immediately after one breeding colony abandoned the nesting site due to predator attacks. The main metabolite of p,p′-DDT, p,p′-DDE, was the OCP residue found at higher concentrations, with a geometric mean of 721 ng/g wet weight. Residues of other pesticides, including some hexachlorocyclohexane isomers, hexachlorobenzene, aldrin, heptachlor, and heptachlor-epoxide, were detected at much lower concentrations. The sum of PCBs was 528 ng/g, with PCB congeners #187 and #153 being the most prominent in eggs. The pattern observed in these compounds of industrial origin corresponded more to Aroclor 1260 than to any other commercial mixture. Levels of organochlorine residues indicate a medium degree of exposure, and they are not considered of any concern for the flamingo population. In particular, neither p,p′-DDE nor PCB levels were found to be correlated with the eggshell thickness.  相似文献   
6.
本研究测定了青海省西宁市与海西蒙古族藏族自治州天峻县夏、冬两季大气颗粒物中有机氯农药(OCPs)和类二噁英多氯联苯(DL-PCBs)的浓度水平.结果表明,青海省大气颗粒物中OCPs主要为DDTs、HCHs.西宁市DDTs和HCHs的平均水平分别为:35 pg·m-3、5.9 pg·m-3(夏季)和93 pg·m-3、11 pg·m-3(冬季),天峻县DDTs和HCHs的平均水平分别为:83pg·m-3、6.4 pg·m-3(夏季)和28 pg·m-3、6.7 pg·m-3(冬季).与亚洲其它地区相比,青海省大气颗粒物中OCPs处于较低水平.西宁市大气颗粒物中DL-PCBs的平均水平分别为:0.52 pg·m-3(夏季),0.99 pg·m-3(冬季),天峻县为:0.58 pg·m-3(夏季)、0.52 pg·m-3(冬季).西宁市夏、冬两季OCPs的平均水平均大于天峻县,而两地DL-PCBs的平均水平相当.本研究中高原地区DL-PCBs的分布特点及变化规律与极地地区的研究相比存在一定的相似性,而DDTs和HCHs则存在差异性.  相似文献   
7.
微波辅助萃取法提取滇池沉积物中的多氯联苯   总被引:1,自引:0,他引:1  
万幸  王彬  赵世民  胡平  李发荣  潘学军 《环境化学》2011,30(10):1781-1787
研究运用微波辅助萃取-固相萃取-气相色谱/质谱检测滇池沉积物中6种指示性多氯联苯(PCB28、PCB52、PCB101、PCB138、PCB153和PCB180).重点优化了微波辅助萃取技术,在萃取温度为100℃和萃取时间为30 min(升温和恒温各15 min)条件下,以30 mL正己烷∶二氯甲烷(1∶1,V∶V)的...  相似文献   
8.
A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls (PCBs) in order to assess the levels of pollution, sources, area distribution, and potential risk for the environment. All methods were rigorously tested and an adequate quality control was ensured. Only one site had no PCBs residues, and the highest total PCBs concentration in the surface soils was 32.83 ng/g. The average concentration in all the soil samples was 4.13 ng/g, signaling low-level pollution. Tetra-, penta-, and hexa-chlorinated biphenyls were dominant species in soil samples, accounting for more than 75% ofΣPCBs in the soil samples. PCB118 was the most abundant congener in all the samples. The PCB118 was about 20% ofΣPCBs. The soil organic matter content showed only a weak correlation with the levels of all PCB congeners, in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues. To a certain extent, the sources and land use seemed to influence the levels of PCBs.  相似文献   
9.
We studied the chemical dechlorination of the polychlorinated biphenyls (PCBs) in some dielectric oils via nucleophilic substitution of the chloro atoms by polyethylene alkoxide. The influence of temperature, ultrasounds, polyethylene glycol (PEG) and base type was investigated. Our findings show that dechlorination of PCBs by chemical treatment is effective at moderate temperature (90–100°C) and is strongly dependent on the nature of matrix oil. Stirring affects the process yield by influencing the homogeneity of the oil/glycol two-phase system. Ultrasounds can improve the process efficiency by making operating conditions less severe. Selected article from the 6th European Meeting on Environmental Chemistry, University of Belgrade, Serbia and Montenegro organized by Prof. Dr. Branimir Jovancicevic ().  相似文献   
10.
Sakurai T  Suzuki N  Morita M 《Chemosphere》2002,46(9-10):1359-1365
Past dioxin (coplanar polychlorinated biphenyl (Co-PCB), 2,3,7,8-substituted polychlorinated dibenzo-p-dioxin (PCDD) and 2,3,7,8-substituted polychlorinated dibenzofuran (PCDF)) fluxes recorded in dated aquatic-sediment cores were analyzed using principal component analysis (PCA). The data set consisted of samples from four cores collected from the Kanto region of Japan. Time trends and spatial differences in the dioxin flux were examined, and the potential relationship to emission sources was investigated. Twenty-five compounds and 58 core slices, corresponding to the later half of the 20th century, were subjected to the analysis. The PCA of both log-transformed and maximum-value-standardized data successfully divided the dioxin compounds into a small number of groups, and three similar clusters of Co-PCBs, PCDDs and penta- to hepta-CDFs were identified. PCB formulations used in the past are judged to have been responsible for the major part of the Co-PCB flux recorded in the sediment cores. However, the relationship to emission sources needs further investigation. It is suggested that most 2,3,7,8-substituted PCDDs and PCDFs are different from Co-PCBs in their emission sources or movements in the environment. The subcore clusters obtained from the PCA of log-transformed data show that the cores from different sampling areas exhibited distinct dioxin fluxes and compositions. Common time trends among the cores were more effectively summarized by the PCA of maximum-value-standardized data focusing on relative time trends. PC scores show that recently the flux of each dioxin compound in the four cores has been generally declining after having reached a peak.  相似文献   
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