Large Volume Injection and Hyphenated Techniques for Gas Chromatographic Determination of PBDEs and Carbazoles in Air
Petter Tollbäck
Doctoral Thesis Department of Analytical Chemistry Stockholm University 2005 1
Doctoral Thesis, 2005 Petter Tollbäck
[email protected] Department of Analytical Chemistry Stockholm University S-106 91 Stockholm
© 2005 Petter Tollbäck ISBN 91-7155-014-3 pp 1-92, Paper V Cover by Holger and Vera Tollbäck Akademitryck AB, Edsbruk, Sweden 2005 2
Till Holger och Vera
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List of contents Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Sammanfattning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 List of papers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Aims . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 PBDEs and carbazoles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Polybrominated diphenyl ethers (PBDEs) . . . . . . . . . . . . . . . . . . . . . . 17 PBDEs – environmental pollutants . . . . . . . . . . . . . . . . . . . . . . . . 18 Biological effects of PBDEs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 PBDEs – an analytical challenge . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Carbazoles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Health effects of carbazoles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Gas chromatography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Chromatographic resolution in GC . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Film thickness of the stationary phase . . . . . . . . . . . . . . . . . . . . . . . . 26 Column length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Inner diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Stationary phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Injection techniques for GC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Vaporizing and non-vaporizing injections . . . . . . . . . . . . . . . . . . . . . . 33 Analyte peak focusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Cold trapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Retention gap focusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Solvent effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Conventional injectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 The on-column injector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 The split/splitless injector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 The programmed temperature vaporizer (PTV) . . . . . . . . . . . . . . 38 At-column injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 The septum equipped temperature programmable injector . . . 39 Direct injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Large volume injection (LVI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Why large volume injection? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Common misconceptions about large volume injections . . . . . . . 42 On-column large volume injection (OC-LVI) . . . . . . . . . . . . . . . . 42 Loop-type injector/interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 5
Concurrent solvent evaporation . . . . . . . . . . . . . . . . . . . . . . . . . Peak deformation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Why loop-type? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Large volume splitless injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . Large volume PTV injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sample introduction and solvent evaporation . . . . . . . . . . . . . . Analyte trapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Analyte transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The author’s note on the loop-type and the PTV injectors . . . . . . GC detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The flame ionization detector (FID) . . . . . . . . . . . . . . . . . . . . . . . . . . The nitrogen phosphorus detector (NPD) . . . . . . . . . . . . . . . . . . . . . The electron capture detector (ECD) . . . . . . . . . . . . . . . . . . . . . . . . . Mass spectrometry (MS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electron ionization (EI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Chemical ionization (CI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electron capture negative ionization (ECNI) . . . . . . . . . . . . . . Sample extraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Static and dynamic extractions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Soxhlet extraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ultrasonication-assisted solvent extraction . . . . . . . . . . . . . . . . . . . . . Dynamic sonication-assisted solvent extraction . . . . . . . . . . . . . . . . . On-line coupling to GC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Benefits of hyphenation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Concerns about hyphenated systems . . . . . . . . . . . . . . . . . . . . . . . . . . LC-GC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NPLC and RPLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heart-cut or back-flush? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . On-line extraction-GC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dynamic microwave-assisted extraction (DMAE)-GC . . . . . . . . . Pressurized hot water extraction (PHWE)-GC . . . . . . . . . . . . . . . Supercritical fluid extraction (SFE)-GC . . . . . . . . . . . . . . . . . . . . . Dynamic sonication-assisted extraction (DSAE)-GC . . . . . . . . . . Air sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The sampling set-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Concluding remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
45 46 48 49 50 50 54 54 55 57 57 57 58 58 60 60 60 63 64 64 65 65 67 67 68 68 68 69 73 73 73 74 74 75 75 77 79 81
Abstract This thesis is based on studies in which the suitability of various gas chromatography (GC) injection techniques was examined for the determination of polybrominated diphenyl ethers (PBDEs) and carbazoles, two groups of compounds that are thermally labile and/or have high boiling-points. For such substances, it is essential to introduce the samples into the GC system in an appropriate way to avoid degradation and other potential problems. In addition, different types of gas chromatographic column system and mass spectrometric detectors were evaluated for the determination of PBDEs. Conventional injectors, such as splitless, on-column and programmed temperature vaporizing (PTV) injectors were evaluated and optimized for determination of PBDEs. The results show on-column injection to be the best option, providing low discrimination and high precision. The splitless injector is commonly used for “dirty” samples. However, it is not suitable for determination of the high molecular weight congeners, since it tends to discriminate against them and promote their degradation, leading to poor precision and accuracy. The PTV injector appears to be a more suitable alternative. The use of liners reduces problems associated with potential interferents such as polar compounds and lipids and compared to the hot splitless injector, it provides gentler solvent evaporation, due to its temperatureprogramming feature, leading to low discrimination and variance. Increasing the injection volume from the conventional 1-3 µL to >50 µL offers two main benefits. Firstly, the overall detection and quantification limits are decreased, since the entire sample extract can be injected into the GC system. Secondly, large volume injections enable hyphenation of preceding techniques such as liquid chromatography (LC), solid phase extraction and other kinds of extraction. Large-volume injections were utilized and optimized in the studies included in this thesis. With a loop-type injector/interface large sample volumes can be injected on-column providing low risk of discrimination against compounds with low volatility. This injector was used for the determination of PBDEs in air and as an interface for the determination of carbazoles by LC-GC. Peak distortion is a frequently encountered problem associated with this type of injector that was addressed and solved during the work underlying this thesis. 7
The PTV can be used as a large volume injector, in so-called solvent vent mode. This technique was evaluated for the determination of PBDEs and as an interface for coupling dynamic sonication-assisted solvent extraction online to GC. The results show that careful optimization of the injection parameters is required, but also that the PTV is robust and yields reproducible results. PBDEs are commonly detected using mass spectrometry in electron capture negative ionization (ECNI) mode, monitoring bromine ions (m/z 79 and 81). The mass spectrometric properties of the fully brominated diphenyl ether, BDE-209, have been investigated. A high molecular weight fragment at m/z 486/488 enables the use of 13C-labeled BDE-209 as an internal surrogate standard.
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Sammanfattning Den här avhandlingen fokuserar på injektionstekniker för gaskromatografi (GC), med avseende på två grupper av ämnen, som är termiskt labila och/ eller har höga kokpunkter: polybromerade difenyletrar (PBDE) och carbazoler. I många fall är provintroduktionen den mest kritiska delen av en GC-analys. Vidare har GC-kolonnsystemet och den masspektrometriska detektionen av PBDE undersökts. Konventionella tekniker så som splitless-, PTV- (programmable temperature vaporizing) och on-columninjektion har utvärderats och optimerats med avseende på haltbestämning av PBDE. Mest tillförlitlig visade sig oncolumninjektionen vara, med låg diskriminering och hög precision. För komplicerade matriser används vanligen splitlessinjektion. Denna teknik är dock inte lämplig för PBDE-kongener med hög bromeringsgrad. Resultaten presenterade i den här avhandlingen visar att precisionen är låg, till följd av diskriminering eller nedbrytning. Istället förslås PTVinjektorn som ett mer lämpligt alternativ. Denna förångningsinjektor är robust mot matrisrester, till exempel lipider och polära ämnen. Temperaturprogrammeringen möjlig gör en mer kontrollerad lösningsmedelsförångning jämfört med splitlessinjektorn, vilket resulterar i lägre diskriminering och högre precision. Att öka injektionsvolymen från de konventionella 1-3 µL till över 50 µL ger två vinster. Detektions- och kvantifieringsgränserna sänks, eftersom hela eller en större del av provextraktet kan injiceras på GC-systemet. Stor volymsinjektioner möjliggör också direktkoppling av upparbetningstekniker, till exempel vätskekromatografi (LC) och olika extraktionstekniker. Storvolymsinjektioner har optimerats och utnyttjats i stor del av arbetet. Med en loopinjektor kan stora volymer injiceras on-column, vilket ger liten risk för diskriminering. Denna injektor har använts för bestämning av PBDE i luft samt som interface för bestämning av carbazoler på LC-GC. Deformation av kromatografiska toppar är ett vanligt fenomen då denna typ av injektor används. Detta problem har undersökts och avhjälpts i det arbete som denna avhandling baseras på. PTV-injektorn kan också användas för injektion av stora volymer. Tekniken har utvärderats för bestämning av PBDE samt som interface för 9
koppling av dynamisk ultraljudsextraktion till GC. Resultaten visar att en noggrann optimering är nödvändig, men också att PTV-injektorn är robust och ger reproducerbara resultat. PBDE detekteras vanligen med masspektrometri i sk “electron capture negative ionization (ECNI) mode”, där bromjonerna (m/z 79 och 81) registreras. Det masspektrometriska mönstret för den fullt bromerade difenyletern BDE-209 har undersökts. Upptäckten av ett fragment vid m/z 486/488 gör att kol-13-märkt BDE-209 kan användas som intern standard, vilket ökar noggrannheten vid bestämning av BDE-209.
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List of papers I
Influence of the injection technique and column system on gas chromatographic determination of polybrominated diphenyl ethers (PBDE) Jonas Björklund, Petter Tollbäck, Christian Hiärne, Eva Dyremark and Conny Östman Journal of Chromatography A 1041, 201-210, 2004 - The author is responsible for a major part of the experimental work and for writing a substantial part of this paper.
II
Large volume injection GC-MS in electron capture negative ion mode utilizing isotopic dilution for the determination of polybrominated diphenyl ethers in air J. Björklund, P. Tollbäck and C. Östman Journal of Separation Science 26, 1104-1110, 2003 - The author is responsible for setting up the injection system, investigating the peak distortion phenomena and for writing a substantial part of this paper.
III Large-volume programmed-temperature vaporizer injection for fast gas chromatography with electron capture and mass spectrometric detection of polybrominated diphenyl ethers P. Tollbäck, J. Björklund and C. Östman Journal of Chromatography A 991, 241-253, 2003 - The author is responsible for a major part of the experimental work and for writing a substantial part of this paper. IV Coupled LC-GC-NPD for determination of carbazole-type PANH and its application to personal exposure measurement P. Tollbäck, H. Carlsson and C. Östman Journal of High Resolution Chromatography 23 (2), 131-137, 2000 - The author is responsible for all the experimental work and partly for writing this paper. V
Dynamic sonication assisted solvent extraction coupled on-line to GC-MS for the determination of PBDEs in air P. Tollbäck and C. Östman In manuscript - The author is responsible for all the experimental work and for writing this paper.
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VI Mass spectrometric characteristics of decabromo-diphenyl ether and the application of isotopic dilution in the electron capture negative ionization mode for the analysis of polybrominated diphenyl ethers J. Björklund, P. Tollbäck and C. Östman Journal of Mass Spectrometry 38 (4), 394-400, 2003 - The author is responsible for experimental work and for writing a substantial part of this paper.
Papers not included in this thesis Enhanced detection of nitroaromatic explosive vapors combining SPE-air sampling, SFE and Large Volume Injection-GC R. Batlle, H. Carlsson, P. Tollbäck, A. Colmsjö and C. Crescenzi Analytical Chemistry 75 (13), 3137-3144, 2003 Automated rotary valve injection for polybrominated diphenyl ethers in gas chromatography J. Björklund, P. Tollbäck, E. Dyremark and C. Östman Journal of Separation Science 26, 594-600, 2003 Evaluation of gas chromatographic injection techniques for PBDE. P. Tollbäck, J. Björklund and C. Östman Organohalogen Compounds 61, 49-52, 2003 Determination of high molecular weight PBDE by isotopic dilution in ECNI-MS. J. Björklund, P. Tollbäck and C. Östman Organohalogen Compounds 61, 163-166, 2003 Evaluation of the gas chromatographic column system for the determination of polybrominated diphenyl ethers J. Björklund, P. Tollbäck and C. Östman Organohalogen Compounds 61, 239-242, 2003
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Abbreviations BDE BDE-47 BDE-49 BDE-99 BDE-100 BDE-119 BDE-153 BDE-154 BDE-183 BDE-191 BDE-197 BDE-203 BDE-206 BDE-207 BDE-208 BDE-209 BTBPE DBC DecaBDE ECD ECNI EI FID GC HeptaBDE HexaBDE LC LVI MS NonaBDE NPD NPLC
BromoDiphenyl Ether 2,2’,4,4’-tetraBDE 2,2’,3,4-tetraBDE 2,2’,4,4’,5-pentaBDE 2,2’,4,4’,6-pentaBDE 2,3’,4,4’,6-pentaBDE 2,2’,4,4’,5,5’-hexaBDE 2,2’,4,4’,5,6’-hexaBDE 2,2’,3,4,4’,5’,6-heptaBDE 2,3,3’,4,4’,5’,6-heptaBDE 2,2’,3,3’,4,4’,6,6’-octaBDE 2,2’,3,4,4’,5,5’,6-octaBDE 2,2’,3,3’,4,4’,5,5’,6-nonaBDE 2,2’,3,3’,4,4’,5,6,6’-nonaBDE 2,2’,3,3’,4,5,5’,6,6’-nonaBDE 2,2’,3,3’,4,4’,5,5’,6,6’-decaBDE Bis(2,4,6-TriBromoPhenoxy) Ethane DiBenzoCarbazole (7-H-dibenzo(c,g)carbazole) DecaBromoDiphenyl Ether Electron Capture Detector Electron Capture Negative Ionization Electron Ionization (previously Electron Impact) Flame Ionization Detector Gas Chromatography HeptaBromoDiphenyl Ether HexaBromoDiphenyl Ether Liquid Chromatography Large Volume Injection Mass Spectrometry NonaBromoDiphenyl Ether Nitrogen Phosphorus Detector Normal Phase Liquid Chromatography
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OC OctaBDE PAC PAH PANH PBDE PentaBDE PTV RPLC RSD SIM SPE TetraBDE Th TriBDE
On-Column OctaBromoDiphenyl Ether Polycyclic Aromatic Compound Polycyclic Aromatic Hydrocarbon Polycyclic Aromatic Nitrogen-containing Heterocyclic Polybrominated Diphenyl Ether PentaBromoDiphenyl Ether Programmed Temperature Vaporizer/Vaporizing Reversed Phase Liquid Chromatography Relative Standard Deviation Selected Ion Monitoring Solid Phase Extraction TetraBromoDiphenyl Ether Thompson, unit for m/z TriBromoDiphenyl Ether
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Aims The main objectives of the work underlying this thesis were to investigate, optimize and evaluate large volume injection for gas chromatographic analysis of thermally labile compounds and compounds with high boiling points (referred to, for convenience, as high-boiling compounds hereafter). The developed techniques were applied to the determination of polybrominated diphenyl ethers (PBDEs) and carbazole-type polycyclic aromatic nitrogencontaining heterocyclics (PANHs) in air. More traditional methods were also investigated in the course of the work. In addition, large volume injectors were utilized as interfaces for coupling clean-up techniques and gas chromatography on-line. These techniques have been developed to improve detection limits and accuracy. Automated, closed systems also reduce the risk of contamination, a common problem when analyzing PBDEs. Determination of the thermally labile decaBDE congener has proven to be troublesome. Conventional gas chromatographic set-ups generally result in severe discrimination against this compound, leading to poor precision and accuracy. The results presented in this thesis may therefore also assist the development of accurate and reproducible analytical methods for determination of PBDEs in environmental samples.
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PBDEs and carbazoles In this thesis the development and use of sensitive methods for determining selected air-borne pollutants are described. The following paragraphs are intended to give a brief introduction to the investigated compounds.
Polybrominated diphenyl ethers (PBDEs) Pollution with polybrominated diphenyl ethers, Figure 1, has been referred to as the new PCB problem. Considering the similarities between PBDEs and PCBs in structure, function and environmental occurrence the comparison is obvious. However, there are also differences, in biological activity and physical properties, for instance. For more extensive discussion of PBDEs as environmental pollutants, the reader is referred to recent reviews that have been published on this topic [1-3]. %U 2
2
%U [
%U\
%U
%'(
3%'(
%U
%U
2
%U
%U
%U
%U
%U
%U
%U
%U 2
%U
%U %U %U
%'(
%U
%U %U
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Figure 1. General structure of PBDEs and three selected BDE congeners.
PBDEs constitute a group of additive flame-retardants that are predominantly found in electronic equipment, furniture and textiles. They are blended into or adsorbed onto the materials to reduce the flammability. Thus, they are not covalently bonded to the host material. Their flame-retarding properties are based on the elimination of free radicals formed during combustion processes [4]. 17
Three technical PBDE mixtures (penta-, octa- and deca-BDE) are commercially used for flame-retarding purposes. The estimated world demand for PBDEs in 1999 was 67,000 tonnes, of which the deca-BDE mixture accounted for about 80 %. The results of a characterization of these products by Sjödin et al. are summarized in Table 1 [5]. As can be seen, synthesis of the technical mixtures is not specific, yielding about twenty congeners ranging from triBDE to decaBDE. Regulations against the use of the penta-BDE and octa-BDE mixtures within the European Union have shifted production towards the deca-BDE mixture in this part of the world. However, the USA and Japan are still using the low molecular weight mixtures. Table 1. Composition of the three technical PBDE-mixtures.
PBDE-mixture Penta-BDE Octa-BDE Deca-BDE
Composition (%) Tri- Tetra- Penta- Hexa- Hepta- Octa- Nona0-1 24-38 50-62 4-8 10-12 43-44 31-35 9-11 0.3-3
Deca0-1 97-98
PBDEs – environmental pollutants Being additive flame retardants, PBDEs could be suspected to migrate from their host polymer to the surroundings. The first evidence of PBDEs in the environment was reported in 1979 by Zweidinger [6] and in 1981 by Andersson and Blomquist [7]. The latter authors discovered a number of BDE congeners in fish from the river Viskan in Sweden. Since then PBDEs have been found in a wide range of environmental compartments, such as sediments [8-11] and sewage sludge [12-15], as well as in various biota. Numerous papers describe the occurrence of PBDEs in marine animals, for example fish [8, 16, 17], seabirds [18] and mammals [19-22]. PBDEs have also been found in human blood [23, 24], adipose tissue [25-28] and human milk [29-34]. Recently high levels of PBDEs have been found in food, particularly fatty fish, sausage and cheese [35]. Zweidinger et al. were the first to report the presence of PBDEs in air, 18
detecting BDE-209 close to a manufacturing plant for brominated flame retardants [6]. Interest in analyzing air with regard to PBDEs has increased in recent years. The publications on this subject are summarized in Table 2. In 1995 Watanabe et al. reported concentrations in the air as high as 3.1 ng/m3 in rural sites in Osaka, Japan [36]. Jaward et al. presented a large-scale investigation of the outdoor air in 22 countries, mainly in Europe [37]. The highest amounts were found in the UK, which has been both the largest producer and user of PBDEs in Europe. Levels of PBDEs in air have also been determined in Sweden [2, 38], USA [39], Canada [40-42], Chile [43], Norway and the UK [44-46] Sjödin et al. determined several BDE congeners including BDE-209 in different indoor environments, and found increased levels in blood from people exposed to high concentrations of PBDEs in their work environment (an electronics recycling plant) [51]. Thomsen et al. found 7-59 pg/m3 of BDE-49 and BDE-99 in laboratory air, which were responsible for blank problems. Harrad et al. measured the PBDE levels in indoor domestic and work environments [45]. They calculated the daily exposure via the respiratory system to be about 7 ng. This short summary of the occurrence of PBDEs in the environment illustrates the global breadth of their distribution as pollutants. Biological effects of PBDEs Information about the biological effects of PBDEs is sparse, but suggests that their bioactivity is low. Their acute toxicity, measured as LD50, has been reported to be 0.5-5 g/kg body weight [4]. Analyses involving oral administration to rats have shown that the low molecular weight congeners are easily absorbed; after five days 86 % of the dose was still retained, and the half-lives were 20-30 days for tetraBDE and 45-119 days for hexaBDE [52, 53]. The bioavailability of decaBDE is low, due to its large size and only 1-10 % is absorbed [54, 55]. The rats’ excretions showed that the PBDEs are metabolized to a large degree. An interesting finding is that following exposure to BDE-209 the levels of hexa- to nonaBDE in rainbow trout were significantly increased [56]. The low molecular weight BDE congeners have been shown to inhibit the binding of the thyroid hormone thyroxine (T4) to transthyretin [57].
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20
Outdoor air
Outdoor air
Indoor and outdoor air
Outdoor air
Indoor and outdoor air
Indoor and outdoor air
Chile
UK and Ireland
Canada
Europe
UK
Canada
c
c
17, 28, 47, 66, 71, 85, 99, 100, 153, 154 c
47, 99, 100, 153, 154
28, 47, 49, 75, 99, 100, 153, 154
(17, 28, 47, 66, 71, 85, 99, 100, 138, 153, 154, 183, 190) 17, 28, 32, 35, 37, 47, 66, 71, 75, 85, 99, 100, 119, 138, 153, 154, 166, 181, 190 c 17, 28, 33, 47, 99, 100, 153, 154, 183 c
47, 99, 100, 153, 154, (190), 209
Passive, Semipermeable membrane devices Organic films from building surfaces collected.
Active, glass fiber filter and two PUF adsorbents Passive, PUF
Active, glass microfiber filter and two PUF adsorbents Active, glass fiber filter and two PUF adsorbents Passive, PUF
Active, SPE Passive, adsorption to glassware Active, quartz filter and XAD-2 adsorbent Active, quartz filter and XAD-2 adsorbent Passive, PUF
Active, glass fiber filter and two PUF adsorbents
Active, quartz filter
Active, Glass fiber filter
Sampling technique
Outdoor: 4.8 Indoor: 42.1
Indoor: 60-15509 Outdoor: 10-33 Indoor: 2-3600 Outdoor: n.d.-4.4 0.8-2.5
Indoor: 76-2088 Outdoor: 39-48 0.06-43
0.22-37
n.d (
