Document Z4w2Q290EoQMG2JMZ4j0N61md

5 Chemosphorc lio. 5i Pl> 231 - 236, 1977* Pergamon Press. Printed in Great Britain. .1 ANALYSIS OF POLYCHLORINATED DIBENZOFURANS IN YUSHO OIL USING HICH RESOLUTION GAS CHROMATOGRAPHY - MASS SPECTROMETRY i ChrJ stoffer Rappe and Anders GarS Department of Organic Chemistry, University of Crnel S 901 87 Cmed, Sweden ; and : Hans Rudolf Buser and Hans-Paul Bonshardt Swiss Federal Research Station ; CH - S820 Wadenswil, Switzerland j .1 j (Received in UX 7 Aoril 1977; accepted for publication 15 April 1977) j Introduction j Polychlorinated biphenyls (PCBs) are industrial chemicals now known to Is widely distributed In the environment. The commercial products are complex mixtures cf at SO different substances. The toxic effect and the bioaccumulation of the discrete PCB- Isomers vary remarkably. ' .j In 1970 Vos t al. identified polychlorinated dibenzofurans (PCDFs) as toxio impurities in European PCBs at the ppm level,^ and the same has also been reported for American and Japanese PCB3. 7 Osins packed-column CC/MS, Bowo3 et, al. found that the most abundant PCDFs had the same retention time as 2, 3,7.C-totra-CDF and 2,3,4,7,8-penta-CDF.'* In 1968 more than 1200 persona in South-Vest Japan were intoxicated by consuming a commercial rice oil contaminated with 1000 ppm of a Japanese PCB (Kanechlor).^ Nagayama et al. analyzed the rice oil (Yusho oil) and found 5 ppm of PCDFs. Consequently, the PCDF concentration in the Yusho oil was about 250 times higher them in ordinary Kanechlor 231 II DSW 038467 STLCOPCB4022291 232 -o. preparations. Dagayaraa et al. also found totra- and penta-CDFs to be most abundant, but they also found small amounts of the tri- and hexachloro isomers.^ Recently, Ecwes et al. have reported that they found three isomers of both the tstra-CDF and penta-CDF, the dominating- tetra-CI'F had the same retention time on a packed column as 2,3,7,8-tetraj CDF.7 ; The toxic effects of the PCDFs are very similar to those reported for the polychlorin ated dlbenzodioxins (PCDDs), in both csbos the 2,3,7,8-tetrachloro compound being the I, most toxio isomer. 1'2 ' 8 Like PCDDs, both PCDFs and certain PCB isomers have been four.d to increase cytochrome P-450 activity and a number of drug metabolizing enzymes. 2 '97 In this paper, we report on the analysis of "Yusho oil C" using glass capillary column GC in combination with different mass spectrometric techniques. Experimental ; The clean-up of the Yusho oil (l.bg) was performed essentially as -, eluding alkaline saponification and chromatography on silica gel. Final chroma::grapr.y was carried out on an alumina-microcolumn using 10 ml portions of 2^ and 50/ methylene chloride in n-hoxane.1*7 The PCDF fraction was carefully evaporated and the residue re- dlssolvod in 100 pi of n-tetradecone. Similarily, a solution of synthatio 2,3,7,8-tetraCDF was prepared in n-tetradecane at a concentration of about 1 ng/yl. Aliquots of 2 pi of sample wore analyzed on 0Y-101 and OV-17 glass capillary columns (22 m x O.36 mm ID) using an isothermal splifcless injection technique as previously described.71 Ths columns were coupled via a fused platinum capillary, leading directly into the lon-source of a Finnigan 1015 D GC-MS (eleotion impact source at 70 eV). The columns were operated at 1?7C (OV-lOl) and 207C (OY-17) with a helium carrier gas pressure of 0.6 - O.a atm. A vaporizer temperature of ZJ0oC was used, the interface was at 250C. Maes specifio detection (mass fragmentography) of PCDFs was carried out by monitoring molecular ions at m/e 270 (tri-CDF), m/e 504 (tetra-CDF), a/e 338 (penta-CDF) and m/e 372 (hexa-CDF). At a further stage complete El mass spectra were recorded using a Finnigan 4000 GC-MS equipped with a 6111 data system. 11 <1 osw 038468 STLCOPCB4022292 <2 v--tMoJ on 3 to -> 9 ro o i i <v 9 *S<T o* 3 oo S' o pI li osr cp:* oSS STLCOPCB4022293 Figure 1 : Kasa fragaentograns (0V-101 glaeu cnt.ill.-u-y columns at 197C) of Yuaho oil showing elution of PCDFs (m/e 270 - tri-, u/e }0+ - toUa-, u/o 7J8 - penta- and m/o 572 - hexa-CHF). DSW 038469 f\> wro Figure 2 : Mass fragnentograms (07-17 capiJJary column at 207C) of Yusho oil showing elution of PCDFs (m/e 270 - tri-* m/tt $04 tofcra-, m/e 55*1 =* penta- and m/o 572 hexa-CDF). sw 038470 o v/l STLCOPCB4022294 Ho. 5 235 Results and Discussion I The mass fragmentograms using OV-lOIand OV-I7 columns are given in Fig. 1 and 2. The 0V-101 is a non-polar column with a good grouping effect according to the number of chlorine atoms. The OV-17 is a semi-polar column, with more spreading of the positional isomers. Consequently, OV-17 appears to be better for an optimal separation of the isomeric PCDFs. Fig. 1 and 2 also allow us to make an estimation of the number of tri-, tetra-, penta- and hexa-CDFs present in the Yusho oil (suspected isomers, Table l). In the case of the most abundant isomers, the discrete PCDFs could be identified by running complete SI mass spectra. All the spectra were in agreement with published data, expected ion clustering and major fragmentation (M+-C0C1, M+-C0C1-C12). Table I | Number of PCDFs in Yusho Oil C15 H4 'fH C!S Suspected isomers Identified isomers a) 66 24 95 41 a) Identified by complete MS, no positional assignment. Identical retention times were found for the major tetra-CDF peak and an authentic sample of the 2,3i7iB-tetra-CDF (501 sec on 0Y-101 and 557 seo on OV-17). By simple com parison of peak heights the estimate was made that 2,3,71 Q-tetra-CDF amounts to at most of the total tetra-CDFs. ' j Our investigation using high resolution GC strongly supports the assumption that 2i37.8-t9tra-CDF is one of the main PCDFs in Yusho oil, an assumption so far only based on separations using packed columns. Optimal separation using high resolution gas chro matography i3 required when it is important to separate between a large number of posi tional isomers. DSW 038471 STLCOPCB4022295 Acknowledgmenta The authors are indebted to Dr. Yoshito Masuda, Fukuoka, Japan for the generous gift of the Yusho oil and to Dr. J.D. McKinney, Research Triangle Park, USA for the 2,3,7,S- tetra -CDF sample. j j1 Ij -R---e---f-e--r-e---n--c--e---s---- I, ii 1. J.D. McKinney, K. Chae, B.N, Gupta, J.A. Moore and J.R. Coldstein, Toxicol. Aool. Phantool..56. 65 (1976). ; | 2. J.A. Goldstein, J.D. McKinney, C.W. Lucier, P. Hickman, H. Bergman and J.A. Moore, Toxicol,Appl. Pharmacol.. 56, 81 (1376). . ; tj I1 J. J.G. Vos, J.H. Koeman, H.L, van der Maas, M.C. ten Noever de Brauw and R.H. ie Vos, Fd. Cosmot. Toxicol., 8, 625 (1970). j 4. J.A.G. Roach and I.H. Pomerantzi, Bull. Environ.Contam. Toxicol., 12, 5JS (1374), 5. G.W. Bowos, M.J. Mulvlhlll, B.R.T. Simoneit, A.L.Burlingame andR.W, Riserr:ugh, Nature, 256, 305 (1975). j 6. J, Nagayama, M. Kuratsune, Y, Masuda, Dull. Environ. Contam. Toxicol.. 15, J (1976). I 1 7. G.W. Bowos, M.J. Mulvihill, B.R.T. Simoneit, A.L. Burlingame and R.W. Risebrough, Paper presented at Workshop on TCDD, Milan, Italy. Oct. 2J-24 (1976). \ 8. K.E. McConnell, J.A. Moore, J.K. Haseman and M.W. Harris, Toxicol. Appl. Phariaool.. 21, 146 (1976). I 9. A. Poland and E, Glover, Mol. Pharmacol.. 736 (1973). 10. H.R. Buser, J. Chromatogr.. 107. 295 (1975). - j 11. H.R. Busor, Anal. Cham.. 46. 1553 (1976). j DSW 038472 STLCOPCB4022296