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1.
Total concentrations of PCDDs and PCDFs were predicted from the concentrations of specifically identified dioxin and furan isomers of each congener group by partial least-squares (PLS). The accuracy of this prediction can be used to evaluate results from different data sets or different sources which were calculated by an automatic identification and quantification program-TASQR.  相似文献   

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3.
Fly ash extracts were fed to male hamster (single dose), male rat (single dose and multiple dose), pregnant and lactating female rat (multiple dose). The retention of four isomers, 2,3,7,8-TCDD, 2,3,7,8-TCDF, 1,2,3,7,8-PnCDD and 2,3,4,7,8-PnCDF, was studied in the liver of the adults, foetuses and liver of the sucklings.

Liver retention was structure dependent and different for both species. Transportation of the isomers via the mother milk was 50–100 times more effective than via the placenta.

After a single intravenous dose of fly ash extract to male rats the elimination of these four isomers was studied in the liver, during a period of 10 days. Elimination rates for 2,3,7,8-TCDD, 1,2,3,7,8-PnCDD and 2,3,4,7,8-PnCDF were in the same range. Pharmacokinetic calculations were done on both tetra congeners, to obtain information about the validity of the published Ke values in the multiple dose experiments with male rats.

For 2,3,7,8-TCDF the Ke value was applicable, but for 2,3,7,8-TCDD the validity of the Ke could not be determined.  相似文献   


4.
Reduction of dioxin emission by a quench reactor with lime spray was investigated in relation to post furnace formation pathways. Results showed that the quench reactor performed to supress post furnace reaction of precursor molecules to form selected congeners of PCDD and PCDF.  相似文献   

5.
《Chemosphere》1986,15(6):693-706
Sixteen individual and two pooled human milk samples were analyzed for PCDDs and PCDFs. All detected PCDD and PCDF congeners had a 2,3,7,8-chlorine substitution pattern.The PCDDs and PCDFs were associated with the lipid fraction of the milk. Major components were 2,3,4,7,8-PnCDF (0.2 – 2.6 ppt), 1,2,3,6,7,8-HxCDD (0.2 – 5.7 ppt), 1,2,3,4,6,7,8-HpCDD (1.3 – 19.1) and OCDD (1.7 – 37.8 ppt), with concentrations on total milk basis.Minor components were 1,2,3,7,8-PnCDD, 1,2,3,7,8,9- and 1,2,3,4,7,8- HxCDD (⩽ 1 ppt). Qualitatively and quantitatively the milk samples from the Netherlands strongly resemble those from Sweden and West-Germany. A linear relationship was found between some congeners. This correlation was highest for congeners having an equal number of chlorine atoms or those with a difference of one chlorine atom.By using a one compartment open model for multiple doses, a maximum liver concentration of approximately 200 ppt 2,3,4,7,8-PnCDF in the neonate was calculated after six months.  相似文献   

6.
Two samples of tab water and double distilled water were chlorinated using chlorine gas. A series of PCDFs could be identified from these experiments, however no PCDDs could be found. The two water samples gave very similar isomeric patterns ( . . tetra-CDFs), however the congener profile (Cl4 --- Cl8) was different. These experiments indicate that all products formed by chlorination reactions are potentially contaminated by PCDFs by a specific “chlorine pattern”.  相似文献   

7.
垃圾焚烧厂焚烧底灰的处理研究   总被引:12,自引:1,他引:12  
系统地研究了常州市环境卫生综合厂垃圾焚烧车间的底灰。研究结果表明,根据中国现行的污染控制标准,该厂的底灰属于一般废物,可以以建筑垃圾的方式处理。但对底灰的分选和分类研究结果表明,底灰含有一定量的未燃烬的有机废物,也有一些可回收利用的废物。因此,底灰应该先分选后,再对无利用价值的渣土作填埋或其他处置。  相似文献   

8.
PCDDs/PCDFs and PCBs in water samples from the Three Gorge Reservoir   总被引:3,自引:0,他引:3  
Chen JA  Luo J  Qiu Z  Xu C  Huang Y  Jin YH  Saito N  Yoshida T  Ozawa K  Cao J  Shu W 《Chemosphere》2008,70(9):1545-1551
The Three Gorge Reservoir (TGR) is the largest reservoir in China and its water quality is an important health concern, we have determined the concentrations of PCDDs/PCDFs and PCBs in the water samples collected at three seasons: August 2004, January 2005 and August 2005. The results showed that the average WHO-TEQ of total dioxins-like compounds (PCDDs/PCDFs+PCBs) was 0.06558 pg l(-1), ranged from 0.0008 to 0.32439 pg l(-1), which are much lower than other reported water sources. The main dioxins (PCDDs/PCDFs) are hepta- and octa-chlorinated dibenzo-p-dioxins (CDDs) and chlorinated dibenzofurans (CDFs). Since the levels of dioxins may change after the last water-store stage, the present study provides important data to compare the water quality in the TGR in the future.  相似文献   

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10.
PCDDs, PCDFs and some related aromatic compounds were determined isomer specifically in sediments from the river Rhine and its tributaries, in order to study sources and environmental fate of these compounds. Additionally, waste water effluents from industries that unintentionally might coproduce PCDDs or PCDFs were analyzed. In all sediments and in some waste water effluents these compounds could be detected. Variations of the isomeric patterns of the PCDFs enabled a distinct industrial area, that was associated with PCB contamination to be identified. The contamination of sediments and organisms from the Dutch river Rhine delta with these compounds mainly could be attributed to the transboundary pollution of the river Rhine.  相似文献   

11.
Analysis for tetra- through octachloro-PCDDs and PCDFs was completed for 46 tissue samples prepared from the U.S. Environmental Protection Agency (EPA) National Human Adipose Tissue Survey (NHATS). The samples were prepared as composites from over 900 specimens to represent the nine U.S. census divisions and three age groups (0–14, 15–44, and 45 plus years). The data demonstrate that PCDDs and PCDFs are prevalent in the general U.S. population and that differences exist with age.  相似文献   

12.
In laboratory-scale combustion of polyvinylidene chloride (PVDC) with a quartz tubular furnace designed and fabricated to provide the desired combustion temperature and mixing state of combustion gas with air, it was found that at 800 degrees C or higher the level of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans [corrected] (PCDDs/PCDFs) resulting from PVDC combustion was no higher than that from heating air alone, and thus far below the levels which resulted from PVDC combustion at 750 degrees C or lower. The results provide the first laboratory confirmation of the relation between PVDC incineration temperature and PCDD/PCDF formation, and of the primary importance of high temperature, turbulence for mixing between air and combustion gas, and sufficient residence time, as governing factors for the minimization of PCDD/PCDF formation in municipal solid waste incinerators.  相似文献   

13.
Presently, in Japan there are no limitations on the emission of PCDDs or PCDFs, but in order to study the feasibility of dry type air pollution control, a pilot plant was constructed in 1988 and the removal efficiencies for PCDDs, acid gas and heavy metals were measured.At the same time PCDDs concentration was compared with that of a previously installed electrostatic precipitator (ESP) plus wet scrubber line.In this paper, the following two items are reported.
1. (1) The difference in the amounts of PCDDs and PCDFs produced due to differences in gas temperature and retention time in ESP and fabric filter (FF).
2. (2) Removal efficiencies of PCDDs and PCDFs of fabric filter.
PCDDs concentration, generally 100–200 ng/Nm3 at the boiler outlet (ESP inlet and/or Quench Reactor (QR) inlet), increased several times at the ESP outlet, but it showed almost no increase at the QR outlet due to a sudden temperature drop. The temperature was 280–310°C, and the gas retention time was 12 sec. during passage through ESP so that it is thought that PCDD was formed under these conditions.On the other hand, a removal efficiency of approx. 90% was obtained with the fabric filter, and the PCDD at the bag outlet was at a sufficiently low level.  相似文献   

14.
PCDDs and PCDFs in vehicle exhaust particles in Japan.   总被引:6,自引:0,他引:6  
Vehicle exhaust particles from gasoline and diesel engine cars were analyzed for PCDDs and PCDFs. The congener patterns of PCDDs and PCDFs in exhaust particles were different between gasoline and diesel engine cars. Suspended particulate matter from electrostatic precipitator connected to a highway tunnel was also analyzed for PCDDs and PCDFs. The congener pattern of suspended particular matter was different from both of gasoline and diesel engine cars. Total amounts of PCDDs/PCDFs sum concentrations in gasoline, diesel and suspended particulate matter were 0.21, 0.87 and 26.0 ng/g, respectively. The I-TEQs levels in gasoline, diesel and suspended particulate matter were 4.2, 11 and 242 pg/g, respectively.  相似文献   

15.
Extraction of heavy metals from MSW incinerator fly ash using saponins   总被引:22,自引:0,他引:22  
An extraction process with saponins was evaluated for removing heavy metals from MSW (municipal solid waste) incinerator fly ashes. Two different fly ashes, A and B, were treated on a laboratory scale with three triterpene-glycoside type of saponins, M, Q, and T, in the pH range 4-9. The results were compared with those of the HCI and EDTA treatment. The treatment with saponins extracted 20-45% of Cr from the fly ashes. Saponins were also effective in extracting Cu from fly ash A attaining 50-60% extraction. Saponin T extracted 100% of Pb from fly ash A at pH around 4. The extraction of Zn with the saponin treatment was similar to that of the HCl treatment. Further, Cr, Cu, Pb, and Zn were fractionated by sequential extraction to investigate the effect of saponins on each fraction. Extraction behavior of other elements during the saponin treatment was also studied. The leaching test on the residues received after the saponin treatment showed that the fly ashes were successfully detoxified to meet the landfilling guideline.  相似文献   

16.
PCDDs, PCDFs, PCBs and DDE in edible marine species from the Adriatic Sea   总被引:1,自引:0,他引:1  
Edible marine species from several areas of the Adriatic sea were analyzed for their content in persistent organic pollutants (POPs), such as polychlorinated dibenzodioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and pp'-DDE (dichlorodiphenyldichloroethylene), a metabolite of the organochlorine pesticide dichlorodiphenyltrichloroethane (DDT). On the whole, PCDD/F contamination levels were low. In general, I-TEQ findings were greater for those species at higher levels in the trophic web (mackerel > red mullet > anchovy). Contamination levels were within 0.23 and 1.07 pg TEQ/g fw (fresh weight) in the aforesaid species, while all remaining species exhibited contamination levels ranging from approximately 0.07 to 0.25 pg TEQ/g fw. Besides, TEQ cumulative findings in species from the northern area were in general greater than those from the central and southern areas. PCB cumulative findings in the samples also revealed a detectable difference in contamination levels in species obtained from the northern, central, and southern sampling sites, between 7.6 and 177, 2.3 and 157, and 4.5 and 94 ng/g fw, respectively. The greatest PCB concentrations were found in mackerel (94-177 ng/g fw). Finally, DDE concentration levels varied from 0.7 to 32.4 ng/g fw. The highest levels of contamination were found in mackerel, red mullet and anchovy (17.7-32.4 ng/g fw, 8.1-9.8 ng/g fw, and 6.4-11.9 ng/g fw, respectively).  相似文献   

17.
This paper describes the analysis of hazardous waste oil samples with procedures that were developed primarily to clean up and analyze biological samples. Details of the cleanup procedure and the results from the analysis of several waste PCB oil samples are presented.  相似文献   

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19.
The sampling procedure of solid and gaseous pollutants, contained in flue gas emitted into the atmosphere by solid waste incinerating furnaces were investigated. Because of their extraordinary toxicological properties, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are taken into particular consideration. The analytical work is based on the use of high-resolution gas chromatography in combination with low-resolution mass spectrometry. Details of the extensive sample clean-up will follow the GC-MS separation and identification of the isomers detected for each group of PCDDs and PCDFs. Quantitative data of these pollutants distribution levels deriving from different investigated incinerators are also reported.  相似文献   

20.
In an interlaboratory study of PCDD and PCDF levels in coffee filter paper, most of the participants were able to quantify 2,3,7,8-TCDF and 2,3,7,8-TCDD. The relative standard deviation for the levels of these substances was in the range of 36 – 46 %. In the participating laboratories, different methods were used. When considering the different solvents used for extraction, it would seem that the reported levels increased with the polarity of the solvent.  相似文献   

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