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1.
Polychlorinated naphthalenes (PCNs) are candidates for inclusion in the Stockholm Convention on persistent organic pollutants. PCNs are structurally and toxicologically similar to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and its analogues. Intake in food is considered to be an important human exposure pathway for PCNs. In this preliminary study, cheese and butter samples were analysed for PCNs, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) using an isotope dilution gas chromatography high-resolution mass spectrometry method. The aim of this study was to evaluate the PCN concentrations in the cheese and butter samples and to compare them with the PCDD, PCDF and PCB concentrations. The PCN concentrations were 5.6–103 pg g?1 of wet weight in the seven cheese samples tested and 5.0–199 pg g?1 of wet weight in the seven butter samples tested. The mass concentrations of lower chlorinated congeners were greater than those of the higher chlorinated congeners. Congeners of CN45/36, CN27/30 and CN33/34/37 were much more abundant than other congeners found in tetrachlorinated PCNs. Congeners of CN51, CN66/67 and CN73 were determined to be the predominant congeners in penta-, hexa- and heptachlorinated homologs, respectively. The PCNs contributed around 5% of the total PCN, PCDD, PCDF and PCB toxic equivalence (TEQ) values. CN73 was found to be the dominant PCN congener and contributed more than 40% to the PCN TEQ value. Congeners CN66/67, CN69 and CN63 were also found at relatively high levels. The PCB congener CB118 was the predominant congener (by mass-based concentration) of the 12 dioxin-like PCBs (dl-PCBs). The PCBs contributed 53.8% of the total TEQ, and congener CB126 contributed more than any other compound that was analysed to the total TEQ. The PCDDs and PCDFs contributed 11.6% and 29.7% of the total TEQ values, respectively.  相似文献   

2.
An automated clean-up system was evaluated for the simultaneous analysis of polychiorinated dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF), and biphenyls (PCB) in different foods. In addition to the seventeen 2,3,7,8-substituted PCDDIPCDF and four non-ortho PCB, by use of the clean-up system studied, it was possible to collect the eight mono-ortho and two di-ortho PCB and the seven indicator PCB in two separate fractions during the same clean-up run. The study was first performed using standard mixtures containing PCDD, PCDF and PCB, and a certified reference material. The recoveries of the 13C-labeled compounds ranged from 51 to 90%, indicating that the PCDD, PCDF, and PCB clean-up worked satisfactorily. Next, the automated system for PCDD, PCDF, and PCB analysis was evaluated for foods such as milk, egg, meat (beef, chicken, and pork), mussel, and olive oil. The recoveries of the 13C-labeled compounds ranged from 40 to 120% for PCB and from 57 to 113% for PCDD/ PCDF, meeting the requirements of well accepted methods. Thus, the automated clean-up system studied is a suitable alternative to conventional clean-up methods.  相似文献   

3.
Summary Coplanar PCB (IUPAC nrs. 77, 126 and 169) have been determined in samples of flue gases and solid wastes from high-temperature processes, and soils and sediment.TEQ-levels of coplanar PCB present have been compared with those of PCDD/PCDF in the samples. It is found that, while in the flue gas samples coplanar PCB contribute less than 10% to the total TEQ level, soils and sediment may contain higher levels (up to 30% of the total TEQ for the samples analyzed).Moreover the pattern of PCB in the samples from high-temperature processes apparently differs considerably from that in the soils and sediment, in which PCB 77 constitutes >70% of the coplanar PCB.  相似文献   

4.
Analytical procedures for the determination of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and non-ortho polychlorinated biphenyls (PCB) require a fractionation step to separate PCDD/F from planar PCB and the bulk of PCB. An HPLC method which achieves the separation of the bulk of PCB (0–6 mL of hexane), mono-ortho PCB (6–8 mL of hexane), non-ortho PCB (8–15 mL of hexane) and PCDD/F (15–50 mL of toluene) on a PYE column (2-(1-pyrenyl) ethyldimethylsilylated silica gel) in a single step without the use of backflush as other authors proposed was developed. The method shows a good accuracy and precision and it is linear in the range studied, e.g from 5.8 to 2420 pg injected in HPLC for TCDD/F, from 28.8 to 12100 pg for PeCDD/F, HxCDD/F, HpCDD/F and from 57.6 to 24200 pg for OCDD/F. It has been successfully applied to the analysis of technical mixtures of PCB (Aroclors), a pine wood sample and several water samples of different origins. Received: 29 November 1998 / Revised: 25 February 1999 / Accepted: 3 March 1999  相似文献   

5.
Analytical procedures for the determination of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and non-ortho polychlorinated biphenyls (PCB) require a fractionation step to separate PCDD/F from planar PCB and the bulk of PCB. An HPLC method which achieves the separation of the bulk of PCB (0–6 mL of hexane), mono-ortho PCB (6–8 mL of hexane), non-ortho PCB (8–15 mL of hexane) and PCDD/F (15–50 mL of toluene) on a PYE column (2-(1-pyrenyl) ethyldimethylsilylated silica gel) in a single step without the use of backflush as other authors proposed was developed. The method shows a good accuracy and precision and it is linear in the range studied, e.g from 5.8 to 2420 pg injected in HPLC for TCDD/F, from 28.8 to 12100 pg for PeCDD/F, HxCDD/F, HpCDD/F and from 57.6 to 24200 pg for OCDD/F. It has been successfully applied to the analysis of technical mixtures of PCB (Aroclors), a pine wood sample and several water samples of different origins. Received: 29 November 1998 / Revised: 25 February 1999 / Accepted: 3 March 1999  相似文献   

6.
The study and extension of a simple automated clean-up method for polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) to a broad range of polychlorinated biphenyls (PCB) is described. The isolation of seven PCDD, ten PCDF, and three coplanar PCB (cPCB) is extended to eight monoortho substituted PCB and seven so-called "marker PCB" (Aroclor 1260) for fatty food samples. This enables quantification of 35 compounds - including all congeners with a WHO toxic equivalent factor (TEF)--in a single extraction and single purification step. The chromatographic behaviour of mono-ortho PCB and marker PCB on a variety of adsorbents, including basic alumina, has been studied. Partitioning of analytes through multi-column sequences is described and correlated with their structural and electronic properties, by use of molecular modelling calculations. The fractionation process available with the Power-Prep automated clean-up system enables rapid independent analysis of the different groups of compounds. Gas chromatography with high resolution mass spectrometry (GC-HRMS) is used for the PCDD/F and cPCB fraction and quadrupole ion-storage tandem in time mass spectrometry (GC-QISTMS) for analysis of the remaining PCB. A comparison study was performed on quality-control samples and real fatty food samples to evaluate the robustness of the new strategy compared with a reference method. On the basis of this simultaneous clean-up, a rapid simplified strategy for PCDD/F and selected PCB analysis determination is proposed for fatty food samples.  相似文献   

7.
Due to safety concerns regarding dietary exposure to POPs, regulatory bodies are issuing detailed guidelines for testing for polychlorodibenzodioxins (PCDDs) and polychlorodibenzofurans (PCDFs) ('dioxins') and dioxin‐like (DL)‐PCBs in foods of animal origin. Determination of the aforesaid chemicals at regulatory levels requires highly selective and sensitive testing techniques. The new generation of low‐resolution mass spectrometers (triple quadrupoles) allows very low levels of quantification to be reached (in the order of tens of femtograms), thus suggesting a potential for their application in food and feed analysis. The performance of the low‐resolution tandem mass spectrometry (LRMS/MS) approach with triple quadrupoles was assessed on a qualified set of food samples from proficiency tests (PTs) and defense analysis. Accuracy was tested comparing the results with data from high‐resolution mass spectrometry (HRMS) and with consensus values from PTs. The cumulative TEQ results were characterized by deviations not exceeding 15% of PCDD + PCDF, DL‐PCB, and PCDD + PCDF + DL‐PCB (TEQTOT) reference consensus values (sample TEQTOT range, 2.29–25.1 pgWHO‐TEQ97/g fat). Congener analytical variabilities did not influence significantly the WHO‐TEQ97 outcome of the corresponding sample. This preliminary performance evaluation highlights the potential of LRMS/MS as a routine technique for quantitative analysis of PCDDs, PCDFs, and DL‐PCBs in food. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

8.
A software has been developed for the peak recognition of 136 polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) after high resolution gas chromatography coupled with mass spectrometry (HRGC/HRMS). Based on the retention times of 13C labelled 2,3,7,8-substituted PCDD/F internal standards, the retention times of all PCDD and PCDF can be calibrated automatically and accurately. Therefore, it is very convenient to identify the peaks by comparing the retention of samples and the calibrated retention times of their chromatograms. Hence, this approach is very significant because it is impossible to obtain always a standard chromatogram and PCDD/F analysis are very expensive and time consuming. The calibration results can be transferred to Excel for calculation. The approach is a first step to store costly and environmentally relevant data for future application.  相似文献   

9.
Summary Isomer-specific determination of polychlorinated dibenzofurans (PCDF) and dibenzo-p-dioxins (PCDD) was carried out in 37 samples of different fish species, crustaea and mussel from a fjord area contaminated by waste water from a Mg-factory. In addition 6 sediment samples were analysed. The tetra- and pentachlorodibenzofuran isomer pattern of the Mg-process is very characteristic and dominated by isomers with chlorine in the positions 1,2,3,7 and/or 8. Very similar patterns were found in sediment, crustacea and mussel samples up to 15 km from the factory. Nearly all isomers were present in crab, shrimp and mussel while fish samples contained mainly 2,3,7,8-substituted congeners. The isomer distributions and concentration levels for different species and tissues with high and low fat content are presented. The applied analysis techniques and the quality assurance procedure as well as practical problems are described in detail. The found levels varied between low ppt- and high ppb-levels for single isomers.
Bestimmung von polychlorierten Dibenzofuranen (PCDF) und Dibenzo-p-dioxinen (PCDD) und deren Isomerenverteilung in Fisch, Crustaceen, Muscheln und Sedimenten einer durch Mg-Produktion verunreinigten Fjordregion
  相似文献   

10.
Summary Polychlorinated dibenzodioxins (PCDD) and polychlorinated dibenzofurans (PCDF) are formed by pyrolysis of chlorophenols and chlorophenates. Under certain conditions the PCDD pattern is completely governed by the chlorine substitution of the starting molecules. Pyrolyses of chlorophenols at elevated temperatures, however, lead to complex PCDD/PCDF mixtures. Nearly all trito heptachlorodibenzodioxin and -dibenzofuran congeners can arise simultaneously from a mixture of only two trichlorophenols. In this case the substitution pattern of the products is no longer influenced by that of the chlorophenols used.
Bildung von polychlorierten Dibenzodioxinen und Dibenzofuranen durch Erhitzen von Chlorphenolen und Chlorphenolaten bei verschiedenen Temperaturen
Zusammenfassung Polychlorierte Dibenzodioxine (PCDD) und polychlorierte Dibenzofurane (PCDF) werden durch Pyrolyse von Chlorphenolen und Chlorphenolaten gebildet, wobei unter bestimmten Bedingungen das PCDD-Muster vollständig von der Chlorsubstitution der Ausgangsmoleküle bestimmt wird. Die Pyrolyse von Chlorphenolen bei höheren Temperaturen führt jedoch zu komplexen PCDD/ PCDF-Gemischen. Fast alle Tribis Heptachlordibenzodioxine und -dibenzofurane können gleichzeitig aus einer Mischung von nur zwei Trichlorphenolen hervorgehen. In diesem Fall wird das Substitutionsmuster der Produkte nicht mehr von dem der eingesetzten Chlorphenole beeinflußt.
  相似文献   

11.
A municipal sewer system has been investigated for the sources of a set of semivolatile compounds, such as polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), polychlorinated biphenyls (PCB), hexachlorobenzene (HCB), 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethene (4,4'-DDE), and chlorinated paraffins (CP), using sewer films as the sampling medium. A cleanup method for these semivolatile compounds in sewer films is described. The project has been undertaken for the differentiation and localization of specific inputs of xenobiotics from defined regions of the city. A unique pattern of PCDD/PCDF found in sewage sludge has led to the search for a specific source within the sewer system, which has finally been localized as a distinct plant. Other organochlorine compounds proved to be significant indicators for industrial and domestic sewers. PCB appeared as an industry correlated parameter, while 4,4'-DDE indicated domestic sewers. Chlorinated paraffins have been detected in the mg/kg range and are markers and indicators for metal-working industries. Finally, the release of CP by the sewage treatment plant, into the nearby river, has been investigated.  相似文献   

12.
2014年1月在杭州市选择5个点位采集大气颗粒物PM2.5样品,采用同位素稀释高分辨气相色谱/高分辨质谱测定PM2.5中的二恶英(PCDD/Fs)和多氯联苯(PCBs),对PM2.5的污染状况以及PM2.5中PCDD/Fs和PCBs的污染水平及分布特征进行了研究。PM2.5的质量浓度范围为85~168 μg/m3,PM2.5污染较重,但与2004年同期相比明显降低。PM2.5中PCDD/Fs的毒性当量(TEQ)为0.277~0.488 pg I-TEQ/m3,明显高于2004年同期采集样品。颗粒物中PCDD/Fs以八氯代二苯并-对-二恶英(OCDD)为主,毒性当量主要贡献者为2,3,4,7,8-五氯代二苯并呋喃(2,3,4,7,8-PeCDF)。PM2.5中PCBs的质量浓度范围为2.9~8.1 pg/m3,二恶英类多氯联苯(DL-PCBs)的毒性当量范围为2.6~6.1 fg WHO-TEQ/m3,污染较低。PCBs在颗粒物中分布以PCB-28为主,但对毒性当量贡献最大的为PCB-126。PCDD/Fs和PCBs的气-固分配特征表现为PCDD/Fs主要分布于颗粒物中,而PCBs主要分布于气相中。  相似文献   

13.
A multidimensional GC-system containing two capillary columns of different polarities, operated within a double oven instrument, was used for the optimized separation of complex isomeric mixtures of various types of chlorinated aromatic compounds such as PCB, PCDD, or PCDF. Electron capture was applied parallel to flame ionization detection to obtain sensitive signals of the PCB or PCDD and the n-alkane standards required for identification by Kovats indices, respectively. Electron capture detection within a valvelessly operated MDGC system forced changes in the usual instrumental set-up, the live-switching coupling piece being located within the second oven of the double oven instrument. This oven is operated isothermally to ensure optimal and interference-free detection, for stable flow conditions within the coupling piece and for the determination of the isothermal retention indices (Kovats), which are much more suitable for identification by retention than the so-called “linear” indices.  相似文献   

14.
Summary Fourteen polychlorinated biphenyl (PCB) congeners were quantified in air samples of the tropospheric boundary layer of the Atlantic Ocean. The samples were taken on the German research vessel Polarstern during north-south cruises across the Atlantic Ocean (1990, 1991), and on the Capo Verde islands in the North Atlantic Ocean (1992). Values for the sum of PCB were between 48 pg/m3 (values for the seven indicator congeners were [in pg/m3]: PCB 28: 1.3; PCB 52: 5.0; PCB 101: 3.0; PCB 118: 0.5; PCB 138: 1; PCB 153: 1; PCB 180: <0.2) in the Westwind Belt of the eastern North Atlantic and 22 pg/m3 (values for the seven indicator congeners were [in pg/m3]: PCB 28: 2.3; PCB 52: 3.4; PCB 101: 0.5; PCB 118: <0.2; PCB 138: <0.2; PCB 153: <0.2; PCB 180: <0.2) in the Westwind Belt of the central South Atlantic. Up to 385 pg/m3 (values for the seven indicator congeners were [in pg/m3]: PCB 28: 2.6; PCB 52: 11.7; PCB 101: 28.4; PCB 118: 9; PCB 138: 21; PCB 153: 18; PCB 180: 5.5) were measured of the coast of South Patagonia. A difference depending on latitude and on terrestrial influenced air masses between the lower and the higher chlorinated congeners was observed. The levels of three- and tetrachlorinated congeners were highest in the Trade Wind regions. The contents of the higher chlorinated congeners had maxima in samples influenced by continental air masses. A correlation of the levels of the lower chlorinated congeners in air over the South Atlantic with the surface water temperature and thus with the temperature dependent gas/water partition coefficient Kgw was observed. Part XVI: Fischer RC, Krämer W, Ballschmiter K (1991) Chemosphere 23:889–900  相似文献   

15.
In this work, the role of phenoxy radicals in polychlorinated dibenzo‐p‐dioxins and polychlorinated dibenzofurans (PCDD/F) formation was investigated by studying the slow oxidation of 2‐chlorophenol (2‐CP) and 2‐chloroanisole (2‐CA) at a gas‐phase concentration of 4 ppm (~2.1 × 104 μg/m3) over a temperature range of 400–800°C. Residence times were maintained at 2.0 ± 0.10 s. PCDD/F reaction products were dibenzofuran, dibenzo‐p‐dioxin, 4‐chlorodibenzofuran, 1‐chlorodibenzo‐p‐dioxin, 4,6‐dichlorodibenzofuran, and 1,6‐dichlorodibenzo‐p‐dioxin (1,6‐DCDD). Major products observed in these experiments were 2,6‐dichlorophenol, 3‐phenyl‐2‐propenal, 1‐indanone, 1,3‐isobenzofurandione, and 3‐phenyl‐2‐propenoyl chloride. The 2‐CP and 2‐CA experiments, along with the variable concentration 2‐CA experiments, showed that the concentration of radicals present in the oxidation system has a significant effect on the PCDD/F product distribution and ultimately the PCDD/PCDF ratio. Also, the observation of dichlorinated phenoxy phenol and dichlorinated dihydroxybiphenyl, the proposed intermediate species in the radical–radical mechanism, suggests that radical–radical mechanism dominates gas‐phase PCDD/F formation. This information will be helpful in constructing a detailed kinetic mechanism of PCDD/F formation/destruction in combustor postcombustion zone. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 531–541, 2002  相似文献   

16.
Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) are widely recognized by the scientific community as persistent organic pollutants due to their toxicity and adverse effects on wildlife and human health. The actual regulation dedicated to the monitoring of dioxins in food is based on the measurement of 17 congener concentrations. The final result is reported as a toxic equivalent value that takes into account the relative toxicity of each congener. This procedure can minimize the qualitative information available from the abundances of each PCDD/PCDF congener: the characteristic contamination profile of the sample. Multivariate statistical techniques, such as principal component analysis (PCA) or linear discriminant analysis (LDA), represent an interesting way to investigate this qualitative information. Nevertheless, they have only been applied to the analysis of contamination data from food products and biological matrices infrequently. The objective of the present study was to analyze a large data set from dioxin analyses performed on various food products of animal origin. The results demonstrate the existence of differences in congener-specific patterns between the analyzed samples. Variability was first demonstrated in terms of the food type (fish, meat, milk, fatty products). Then a variability was observed that was related to the specific animal species for meat and milk samples (bovine, ovine, porcine, caprine and poultry). Some practical applications of these results are discussed. The origin(s) of the observed differences, as well as their significance, now remain to be investigated, both in terms of environmental factors and transfer through living organisms. A better knowledge of the relation between a contamination profile and its specific source and/or food product should be of great interest to scientists working in the fields of contaminant analysis, toxicology and metabolism, as well as to regulatory bodies and risk assessors in charge of final decisions regarding the eventual hazards associated with theses substances.  相似文献   

17.
Levels and patterns of polychlorinated biphenyls (PCBs) were studied in surface soil samples collected in the coastal part of Croatia within and surrounding four different airports and in the vicinity of two partially devastated electrical transformer stations. The compounds accumulated from air-dried soil samples by multiple ultrasonic extraction with an n-hexane?:?acetone 1?:?1 mixture were analysed by capillary gas chromatography with electron capture and ion-trap detection. PCBs were quantified against a standard Aroclor 1242/Aroclor 1260 mixture and a standard mixture of 17 individual PCB congeners (IUPAC No.: 28, 52, 60, 74, 101, 105, 114, 118, 123, 138, 153, 156, 157, 167, 170, 180, and 189). The mass fractions of total PCBs in 18 soil samples collected within the airport premises ranged from 3 to 41?327?µg/kg dry weight (dw) (median: 533?µg/kg?dw), and those in 21 samples collected at a distance ranging from several metres to 5?km away from the airport fence, from <1 to 39?µg/kg?dw (median: 5?µg/kg?dw). The highest PCB levels were determined in soils along the airport aprons where the aircrafts were serviced and refuelled. The PCB pattern was very similar to technical Aroclor 1260 in all airport soils. The PCB pattern in 22 soils collected in the vicinity of electrical transformer stations was dominated by congeners contained in Aroclor 1242. These soils contained 7 to >400?µg/kg?dw of total PCBs. One highly PCB-contaminated airport soil sample was analysed for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). With an international toxic equivalent (I-TEQ) of 9.7?ng/kg?dw, the airport soil contamination was within values typical for urban and rural areas, and the congener patterns gave no clear indication for PCBs as the only source of PCDDs/PCDFs.  相似文献   

18.
Summary A HPLC method for the clean up of PCDD and PCDF samples is presented. The method utilizes the possibility of separating compounds according to the number of double bonds by using an amino bonded stationary phase. Aliphatics as well as compounds with higher aromaticity than PCDD/PCDF are removed. In addition, the latter can be collected as one fraction. The fractionation in fast, done in one step and automated.  相似文献   

19.
Zusammenfassung Für die Bestimmung von polychlorierten Dibenzodioxinen (PCDD) und polychlorierten Dibenzofuranen (PCDF) in Motorenölen, Altölen und Zweitraffinaten wird ein Verfahren zur Anreicherung und Reinigung beschrieben, das für eine Nachweisgrenze von ca. 0,05 g/kg für die Einzelkomponenten untersucht wurde. Die Ölproben werden nacheinander über Alumina Woelm B Super I, eine gemischte Säule aus Kieselgel, Kieselgel/H2SO4, Kieselgel/NaOH und anschließend über Bio-Beads S-X3 chromatographiert und danach eine GC/MS-Analyse durchgeführt. Die Analyse von Motorenölen (Erstraffinaten) ergab, daß auch nach einer Laufleistung von 10 000 km in PKW-Motoren, die mit verbleitem Benzin betrieben wurden, keine PCDD/PCDF nachweisbar sind. Andererseits wurden in Altölen und daraus hergestellten Zweitraffinaten PCDD/ PCDF nachgewiesen, als deren Quelle das in der Mineralölindustrie eingesetzte Pentachlorphenol, das PCDD/PCDF als Nebenkomponenten enthält, identifiziert wurde. anderem in Motorenölen anreichern können. Außerdem wurde in den Medien mehrfach über den Nachweis von PCDD und PCDF in Altölen und Zweitraffinaten berichtet. Da in der Literatur für die Bestimmung von PCDD und PCDF in Ölen nach unserer Kenntnis kein Verfahren zur Anreicherung und Reinigung beschrieben ist, haben wir hierzu Untersuchungen durchgeführt. Im folgenden wird ein allgemein anwendbares Verfahren zur Bestimmung von PCDD und PCDF in Motorenölen, Altölen und Zweitraffinaten beschrieben.
Determination of polychlorinated dibenzodioxines and polychlorinated dibenzofurans in oil samples
Summary A clean-up procedure for the determination of polychlorinated dibenzodioxines (PCDDs) and polychlorinated dibenzofurans (PCDFs) in motor oil, used oil and recycled oil is described. The procedure was tested for a limit of detection of 0.05 g/kg for single isomers. The oil sample is chromatographed consecutively on Alumina Woelm B Super I, a mixed column of silica, silica/H2SO4, silica/ NaOH and finally on Bio-Beads S-X3. In motor oils, used for 10,000 km in cars run on leaded gasoline, no PCDDs or PCDFs could be detected. However, in used oil samples, collected from various sources, and in recycled oil produced from them, PCDDs and PCDFs were found. Pentachlorophenol, which is used in the mineral oil industry, and which contains PCDDs and PCDFs as side products, was identified as a source of these PCDDs and PCDFs.


Die Untersuchungen wurden mit Unterstützung des Ministeriums für Ernährung, Landwirtschaft, Umwelt und Forsten Baden-Württemberg durchgeführt. Wir danken Herrn Kerzenmacher und Herrn Tichaczek für ihre sorgfältige Arbeit bei den Probenaufarbeitungen.  相似文献   

20.
An automated cleanup system (Power-Prep, Fluid Management Systems, Inc.) was evaluated for the analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) in environmental samples. The study was firstly carried out against standard mixtures containing labeled and unlabeled PCDD/PCDF and a certified reference material (fly ash CRM 490). Next, a comparison between a conventional cleanup procedure and the new automated system for PCDD/PCDF analysis in environmental samples such as flue gas emissions, fly ashes, sludges, ambient air and soils was also made. The suitability of the system was finally assessed from the participation in an interlaboratory exercise. Owing to its capability to successfully perform the sample cleanup the Power-Prep apparatus is an alternative to the conventional methods.  相似文献   

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