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31.
Levels of PCDDs, PCDFs and non-ortho PCBs in serum samples of non-exposed individuals living in Madrid (Spain) 总被引:1,自引:0,他引:1
In an attempt to evaluate the background levels of PCDDs, PCDFs and non-ortho PCBs in people living in Madrid (Spain), blood serum samples had been analyzed PCDD, PCDF and coplanar PCB levels from non exposed individuals are reported in this study. Average levels found were 515.29 ppt for total PCDDs, 66.73 ppt for total PCDFs and 85.47 ppt for non-ortho PCBs on a lipid weight basis Calculated I-TEQ values were 8.78 ppt for PCDDs, 6.96 for PCDFs and 7.03 for coplanar PCBs on a lipid weight basis. 相似文献
32.
Wolfgang K?rner 《Umweltwissenschaften und Schadstoff-Forschung》2005,17(2):115-121
Zusammenfassung
Ziel und Absicht Der derzeitige Kenntnisstand zu Quellen, Verbleib in der Umwelt, Exposition des Menschen und gesundheitlicher Bewertung von
dioxin?hnlichen polychlorierten Biphenylen (PCB) und nicht dioxin?hnlichen PCB wird mit Fokus auf den deutschsprachigen Raum
dargestellt und zusammengefasst.
Methoden Grundlage für den aktuellen Kenntnisstand sind die Vortr?ge und Diskussionsergebnisse eines zweit?gigen bundesweiten Statuskolloquiums.
Die Bedeutung der dioxin?hnlichen PCB wird insbesondere in Relation zu den polychlorlerten Dibenzo-p-dioxinen (PCDD) und Dibenzofuranen
(PCDF) betrachtet. Dazu dient in erster Linie ein Vergleich der Toxizit?ts?quivalentkonzentrationen (TEQ) beider Stoffgruppen
in den betrachteten Umweltmatrices.
Ergebnisse und Schlussfolgerungen In vielen Umweltmedien sind die TEQ-Werte der dioxin?hnlichen PCB ?hnlich hoch wie die PCDD/PCDF-Gehalte, in den meisten Lebensmitteln
tierischen Ursprungs sogar h?her. In den meisten Medien hat das nichtortho substituierte PCB 126 aufgrund seines hohen Toxizit?ts?quivalenzfaktors
von 0,1 den mit Abstand h?chsten Beitrag zum PCB-TEQ. Für die gro?fl?chige Umweltbelastung mit PCB ist offensichtlich der
atmosph?rische (Fern) Transport wesentlich. Für den Eintritt der dioxin?hnlichen, PCB in terrestrische Nahrungsketten ist
der Transfer Atmosph?re-Pflanze wahrscheinlich der entscheidende Schritt.
Empfehlungen und Ausblick Trotz des Rückgangs der Umweltbelastung mit PCB und PCDD/PCDF überschreitet ein erheblicher Teil der Bev?lkerung in Deutschland
und anderen europ?ischen Staaten gegenw?rtig noch die duldbare Aufnahme an, dioxin?hnlichen Substanzen. Aber auch aufgrund
einer aktuellen toxikologischen Neubewertung der nicht-dioxin?hnlichen PCB muss die Verminderung der PCB-Exposition weiter
betrieben werden.
OnlineFirst: 11. April 2005 相似文献
33.
Jones PD Newsted JL Henningsen G Slocomb J Giesy JP 《Environmental science and pollution research international》2005,12(4):189-198
Background, Aims and Scope The Rocky Mountain Arsenal (RMA) is a US Army facility located northeast of Denver, Colorado that has been listed on the
National Priorities List (NPL). It is currently being re-mediated under the authority of the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA) and the Superfund Amendments and Reauthorization Act of 1986 (SARA). As part
of the remediation activities at RMA, indications were found that a source of polychlorinated dibenzo-p-dioxins (PCDDs) and
polychlorinated dibenzofurans (PCDFs) had existed on the RMA. As a result, investigations were undertaken to assess the possible
nature and extent of any potential sources of PCDDs and PCDFs on the RMA site. In addition, other studies were conducted that
examined PCDD/PCDF contamination in the Denver area. The goal of these studies was to examine nature and extent of PCDD/PCDF
contamination both on the RMA as well as in the surrounding Denver area. The intent of this study was to characterize sources
of dioxins (PCDDs) and dibenzofurans (PCDFs) at low environmental concentrations which might have originated from diffuse
sources in the Denver Colorado area and in particular, the Rocky Mountain Arsenal (RMA) using Principal Component Analysis
(PCA).
Methods Over 200 soil samples were collected from the RMA and the Denver area. From the RMA, soil was collected as part of three
studies that included a (1) random site-wide sampling of the RMA, (2) soils from the Western Tier Parcel (WTP), and (3) soils
from Historic Use areas. Denver area soil samples were collected from five different land use categories: Residential, Agricultural,
Open Space, Commercial, and Industrial. PCA was conducted on concentrations of 17 2,3,7,8-substuituted PCDD and PCDF congeners
in 220 soil samples collected from the RMA and the Denver Front Range region.
Results and Discussion PCA demonstrated the presence of possible minor sources of dioxins on the RMA. Current remediation efforts on RMA will result
in the removal of these sources. Samples from the RMA were identified by the presence of a congener profile containing higher
chlorinated PCDFs while the Denver Front Range areas were characterized by the presence of higher chlorinated PCDD congeners.
The presence of a PCDF signature for the RMA samples does not necessarily indicate a major source of these contaminants on-site.
Indeed, the relatively diffuse nature of the sample clusters would argue strongly against the presence of a single large source.
Instead, the predominance of the PCDF congeners probably indicates the mixed industrial activities that took place on and
near the site.
Conclusion PCA results indicate that PCDD/PCDF profiles in soils collected from the RMA differed from those collected from the outlying
Denver areas but that a major source of these contaminants was not present. Rather, the diffuse nature of sample clusters
from the PCA indicated that the congener profile of RMA samples was most likely a result of the mixed industrial activities
that historically have taken place on and near the site. PCA also indicated that many of the 'open area' (peripheral site-wide)
RMA soils samples did not differ from Denver are reference congener profiles. This finding was also true for samples collected
from the WTP that were essentially indistinguishable from Off-RMA reference samples. In addition, total TEQ concentrations
in soils collected from WTP were similar to those measured in soils collected from the Denver Front Range areas indicating
that lack of a major source of PCDD/PCDF within the WTP zones of the RMA.
Recommendation and Outlook Analytical as well as statistical results of the soil congener data indicate that the WTP soils are indistinguishable from
soils collected from non-industrial areas in the Denver area. This finding would support the recent 'de-listing' of the WTP
from the other RMA areas and its' transfer to other authorities in the Denver area. 相似文献
34.
Effects of inorganic chlorine source on dioxin formation using fly ash from a fluidized bed incinerator 总被引:2,自引:0,他引:2
LU Sheng-yong YAN Jian-hu LI Xiao-dong Ni Ming-jiang CEN Ke-f DAI Hui-fen 《环境科学学报(英文版)》2007,19(6):756-761
Chlorine source is indispensable for polychlorinated dibenzo-p-dioxin and furan (PCDD/F) formation during municipal solid waste (MSW) incineration. Inorganic chlorine compounds were employed in this study to investigate their effects on PCDD/F formation through heterogeneous synthesis on fly ash surfaces. A fly ash sample obtained from a fluidized bed incinerator was sieved to different size fractions which served as the PCDD/F formation sources. The capability of different metal chlorides which facilitate the formation of PCDDs/Fs was found to follow the trends: Na < Mg < K < Al < Ca, when two particle fractions of >177 μm and 104-125 μm were used in the experiments. However, the capability of NaCl, MgCl2 and KCl did not seem much different from each other, whereas CaCl2 and AlCl3 were much more active in PCDD/F formation. NaCl and MgCl2 were relatively effective to produce more PCDDs, while KCl, AlCl3 and CaCl2 generated more PCDFs during heterogeneous reactions occurring on fly ash. 2,3,7,8-TCDF was the most significant contributor to the toxicity of the PCDDs/Fs formed from inorganic chlorine sources. Decreasing the sizes of fly ash particles led to more active formation of PCDDs/Fs when NaCl was used as inorganic chlorine in the experiment. The highest PCDDs/Fs produced from particles with size <37 μm, while the lowest PCDDs/Fs produced from particles with size >177 μm. The toxicity generally increased with decreasing size of the fly ash particles. The formation of PCDDs was mainly facilitated by the two size fractions, 104-125 μm and <37 μm, while formation of PCDFs was favored by the two other size fractions, >177 μm and 53-104 μm. 相似文献
35.
YAN Jian-hu PENG Zheng LU Sheng-yong DU Chang-ming LI Xiao-dong CHEN Tong NI Ming-jiang CEN Ke-fa 《环境科学学报(英文版)》2007,19(11):1404-1408
PCDD/Fs have been become a serious issue because of their toxicological effects and associated adverse health implications.In this study,the gliding arc plasma was tested for treatment of polychlorinated dibenzo-p-dioxins(PCDDs)and polychlorinated dibenzofurans (PCDFs),which was synthesized from pentachiorophenol in atmospheric condition at 35℃with or without the catalysis of CuCl_2. From the experiment,we found that the destruction efficiency of PCDD/F homologues after gliding was discharge ranged from 25% to 79%.This result demonstrates that gliding arc plasma is an effective technology to decompose PCDDs/Fs in flue gas.A plausible degradation mechanism for PCDD/Fs by gliding arc was discussed.Finally,a multistage reactor structure of gliding arc was proposed to upgrade removal efficiency for PCDD/Fs. 相似文献
36.
多氯代二苯并呋喃(PCDFs)是一种典型的持久性有机污染物(POPs),光解是其在环境中转化的主要途径.以分子电性距离矢量(Molecular Electronegativity Distance Vector,MEDV)为参数,应用多元线性回归(Multiple Linear Regression,MLR)和偏最小二乘回归(PLSR)对48种PCDFs在云杉针叶和飞灰表面的光解半衰期(t1/2)进行模拟分析,均获得由2个变量所建的定量结构-性质相关(QSPR)模型.多元线性回归结果:建模相关系数(R)分别为0.860和0.836,标准偏差(SD)分别为0.052和0.053,交互检验复相关系数(Rcv)分别为0.839和0.807,外部检验相关系数(Qex)t分别为0.939和0.853;偏最小二乘回归结果:建模相关系数(R)分别为0.857和0.829,交互检验复相关系数(Rcv)分别为0.849和0.807.结果表明,MEDV能较好地表征该类分子的结构信息,所建QSPR模型具有良好的稳定性和预测能力. 相似文献
37.
Jinlong XIE Yuyan HU Dezhen CHEN Bin ZHOU 《Frontiers of Environmental Science & Engineering》2010,4(1):108-115
Researches on the hydrothermal treatment of municipal solid waste incineration (MSWI) fly ash were conducted to eliminate dioxins and stabilize heavy metals. In order to enhance decomposing polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) during hydrothermal process, a strong reductant carbohydrazide (CHZ) is introduced. A hydrothermal reactor was set up by mixing raw MSWI fly ash or the pre-treated fly ash with water and then heated to a pre-set temperature; CHZ was spiked into solution according to specially defined dosage. Experimental results showed that under the temperatures of 518 K and 533 K, the decomposition rates of PCDDs/PCDFs were over 80% and 90%, respectively, by total concentration. However, their toxic equivalent (TEQ) decreased only slightly or even increased due to the rising in concentration of congeners 2, 3, 7, 8-TCDD/TCDF, which might be resulted from the highly chlorinated congeners losing their chlorine atoms and being degraded during the hydrothermal process. Better results of TEQ reduction were also obtained under the higher tested temperature of 533 K and reactor with addition of 0.1%wt CHZ was corresponded to the best results. Good stabilization of heavy metals was also obtained in the same hydrothermal process especially when ferrous sulphate was added as auxiliary agent. 相似文献
38.
Shinsuke Tanabe Narayanan Kannan Tadaaki Wakimoto Ryo Tatsukawa Taku Okamoto Yoshito Masuda 《毒物与环境化学》2013,95(4):215-231
In the light of new discoveries on the extremely toxic non‐ortho coplanar 3,3’,4,4'‐tetra‐ (T4CB), 3,3’,4,4’,5‐penta‐(P5CB) and 3,3'4,4’,5,5'‐hexachlorobiphenyl (H6CB) and their mono‐ and di‐ortho analogs, tissue samples of a Yusho poisoning victim and Yusho causal oils were subjected to a thorough congener/isomer‐specific investigation for polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), polychlorinated dibenzo‐p‐dioxins (PCDDs). Among the many PCB congeners detected in Yusho oil, non‐ortho coplanar T4CB constituted 3.1%, P5CB‐0.17% and H6CB‐0.0072% in total PCBs. Their concentrations in liver and adipose tissue were 130–700 (T4CB), 54–720 (P5CB) and 50–380 (H6CB) pg/g on wet weight basis. The observed concentrations in adipose tissue were two to four fold higher than that detected in unexposed individuals. Among the PCDFs identified, toxic 2,3,7,8‐substituted isomers including 2,3,4,7,8‐P5CDF were the dominant ones. Tetra‐ through hepta‐CDDs were detected in the oil, whereas octa‐CDD was the dominant isomer in the patient. A comparison with KC‐400 revealed enrichment of coplanar PCBs in Yusho oil along with toxic PCDFs. Enrichment was highest for 3,3'4,4'5,5'‐H6CB followed by 3,3’,4,4'5‐P5CB. A comparative toxic evaluation of these chemical groups in Yusho patient's adipose tissue based on “2,3,7,8‐T4CDD Toxic Equivalent Analysis” revealed accountable toxic contribution from coplanar PCBs. This analysis also confirmed that 2,3,4,7,8‐P5CDF was the principal causative agent in Yusho poisoning. 相似文献
39.
Evaluation of the dioxin removal efficiency of the air pollution control device (APCD) at an existing municipal waste incinerator (MWI) located in Taiwan is conducted via stack sampling and analysis. The MWI investigated is equipped with cyclones, dry lime scrubbing systems and fabric filters as APCDs. Results indicate that the patterns of dioxin isomers at APCDs' inlet and stack are similar. During the first year of carbon injection, the concentrations of emitted dioxin decreased greatly. The dioxin removal efficiency increased from 26.9% to 96.6% after injecting 115 kg/day activated carbon (AC). At the second year, the dioxin removal efficiency reaches 98.7% after injecting the same rate of AC continuously. The lower efficiency achieved with activated carbon injection (ACI) during the first year can be attributed to the memory effect, i.e. the dioxin or precursor desorbs slowly to the flue gas and increases the dioxin concentration at stack, resulting in a lower dioxin removal efficiency than expected. 相似文献
40.
单苯环氯取代指数法预测二■英类化合物PCDFs的正辛醇/水分配系数 总被引:17,自引:0,他引:17
采用单苯环氯取代指数作为二恶英类化合物多氯代二苯并呋喃(PCDFs)的分子结构描述符,通过正向逐步线性回归方法建立了PCDFs的正辛醇/水分配系数(lgKow)与分子结构描述符之间的定量关系模型。与有关文献报道的模型相比,该模型不仅具有显著的相关性(n=51,Radj=0.871,SE=0.17334,在a=0.05时,F=38.647,p0.000),而且对于分子结构具有更好的区分能力,利用建立的模型,对没有lgKow文献值的其他85种PCDFs化合物给出了预测值。 相似文献