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Sinkkonen S Lahtiperä M Vattulainen A Takhistov VV Viktorovskii IV Utsal VA Paasivirta J 《Chemosphere》2003,52(4):761-775
Persistent aromatic bromine, chlorine and mixed chlorine-bromine compounds were analysed from recycled aluminium smelter (ALS) ashes to explore the impact of brominated flame retardants (BFR) on their formation. Polybrominated diphenyl ethers (PBDE) were the most abundant original BFRs found. Induction furnace ash contained tetra- to octa-BDEs about 2000ng g(-1) in similar congener ratios as the original scrap, but contents of nona- and deca-BDEs were only 25 and 5ng g(-1) indicating their significant degradation in ALS process. In the most non-polar fraction, PCB levels and profiles were similar as earlier ALS ash samples in 1990s. The highest PCB level measured was that of deca-CB (450ng g(-1)) in the induction furnace ash. In this fraction, bromo compounds were non-detectable (<5ng g(-1)). Fraction of the most polar compounds (from reversed toluene elution of carbon column ("dioxin fraction") contained PCDDs, PCDFs and polychlorinated dibenzothiophenes (PCDTs) in similar amounts and congener profiles as earlier investigated ALS ash samples. Bromine-containing dioxin and furan congeners were not detected. From individual PCDDs and PCDFs, octaCDF was the most abundant (205ng g(-1)) in induction furnace ash. In this fraction, the original BFR, tetrabromo-bisphenol-A, was identified. Its level in the induction furnace ash was approximated to be 388ng g(-1). In addition, 12 novel brominated and chlorinated compounds were found as abundant (8-441ng g(-1) in the induction furnace ash) contaminants from the fraction. Four of them were bisphenol derivatives, five biphenylols, then octachlorofluorenone (OCFL) and octachlorobiphenylene (OCBP). Their structures or structure types were deduced from total low-resolution EI mass spectra by theoretical isotope cluster simulation (ICLU) and through known fragmentation rules. 相似文献
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Khoroshko LO Petrova VN Takhistov VV Viktorovskii IV Lahtiperä M Paasivirta J 《Environmental science and pollution research international》2007,14(6):366-376
Background, Aims and Scope Despite the large number of studies on the forms of sulfur in marine deposits, investigations on sulfur organic compounds
are still rare. It is known that the processes leading to formation of intermediate and final sulfur compounds (including
organic ones) in modern deposits are the results of microbiological transformation of sulfur containing proteins, as well
as the microbiological reduction of sulfate ions. The latter are finally reduced by anaerobic sulfate-reducing bacteria to
H2S, HS− and S2−; the total sum of these is referred to as ‘hydrogen sulfide’ in chemical oceanography. Further, the formation of reduced
sulfur organic derivatives (sulfides and polysulfides) is the result of interaction of the organic substance destruction products
with the sulfide ions. In such cases, the main source of organic substances, as well as sulfates for the sulfur reducing processes,
is the pore water in the sediments. The choice of the target of our study is based on the fact that the eastern part of the
Gulf of Finland water area receives the bulk of the anthropogenic load of the St. Petersburg region. Low vertical intermixing
of the water thickness is observed there (thus creating a deficiency of oxygen near the bottom), and the bottom sea current
transfers the polluted salty water of the Baltic Sea into the Neva Bay. The whole of the above are the preconditions for the
formation of sulfur-bearing organic compounds.
A great number of bottom sediment samples for analytical surveys were collected in the Eastern Gulf of Finland during research
expeditions in the years of 1997 and 2001. These were screened for structures of sulfur organic microcontaminants, including
organic forms of sulfur, using advanced instrumentation and experienced personnel in our two, cooperating laboratories. This
work is a part of the research being carried out on organic micro-admixtures present in bottom sediments, and is the summary
of our findings on previously unstudied sulfur organic substances there.
Materials and Methods A number of sulfur organic compounds present in nineteen bottom sediment samples from the Eastern Gulf of Finland (EGF) were
characterized by high performance gas chromatography connected to low and high resolution mass spectrometers (GC/LRMS and
GC/HRMS). The structure screening was carried out as compared with literature and library mass spectra, and taking the GC
retention times into account. In the cases of an absence of mass spectra not in the literature, interpretation of the most
probable structures was performed with the help of high resolution mass-spectrometric data, fragmentation rules for sulfur-bearing
organic substances and ICLU simulation of spectra. These data were registered to form a conclusive ‘fingerprint’ for identification
and confirmation of the structure of each novel compound found, e.g. by later syntheses of authentic model compounds. The
relative contents of sulfur organic compounds were determined from MS response ratios of each compound to 2-fluorine naphthalene
(internal standard).
Results This paper is a completion of work, which has been published in part as three papers in the European Journal of Mass Spectrometry.
As the total study result, 43 sulfur-bearing compounds were characterized. The mass spectra of 20 of them were found in the
literature. The most probable structures for the 23 compounds whose mass-spectra were not available in the literature data
were proposed. All of those 23 compounds were detected in bottom sediments for the first time, and 5 of them were described
as originating from plants or being generated by chemical synthesis products, while the remaining 18 substances were previously
unknown. The structures of these were deduced to be most probably the following (in order of their GC retention): dichloromethyl
thiylsulfenylchloride, chloromethyl dichloromethyl disulfide, 3,4-dithiacyclohexene, 1,2,4-trithiacycloheptane, 1,2,3-trithiacyclohexane,
tetrathiacyclopentane, 3,4,5-trithiacyclohexene, 1,2,4-trithiacyclohexane, cyclopropylhydrotrisulfide, 1,2-dithiane-3-thiol,
1,3-dithiane-2-thiol, bis(trichloromethyl)-tri-sulfide, 1,2,4,5-tetrathiacyclohexane, 1,2,3,4-tetrathiacycloheptane, 1,2,3,4-tetrathiacycloheptane,
1,2,3,4-tetrathia-cyclo-hexane, pentathiacyclohexane, and 1,2,4,6-tetrathiacyclooctane. The highest amounts of sulfur organic
compounds were found in the deepest, bottom areas in the open part of the sea, where the salinity was highest, and oxygen
deficiency occurred as well. Also, some coastal places with a high solid matter deposition rate had elevated contents of sulfur
organic compounds.
Discussion From the 43 sulfur organic compounds found, the HRMS data provided the atomic composition of the molecular ions for 16 compounds
with a high confidence (see Table 3). The LRMS spectra could be identified with catalogue or literature spectra in 29 cases.
The MS information obtained was insufficient in two cases: 1) The obvious molecular ion (at m/z 110) of compound 1 was not
visible in LRMS. 2) For compound 43, the HRMS measurement, due to the low intensity (2%) of the molecular ion (m/z 210), could
not exclude the presence of 2 oxygen atoms (instead of one sulfur atom) in the molecule. Major fragments, however, of our
43, certainly contained no oxygen atoms according to HRMS. The limited LRMS data in the literature, for an isomer of 43, had
m/z values of all fragments different from those of the compound found by us.
The retention times (RT) formed one more evidence for identity between compounds in different samples. The use of different
non-polar columns in GC and similar, but not identical, temperature programs produced eluted peaks of novel and known compounds
in each sample (mixture) in GC/HRMS and GC/LRMS. These gave sets of RTs which were in a very significant linear correlation
(measured example R = 0.999866, p = 1.85E-06, N = 5). Therefore, the RTs in the HRMS analysis systems could be converted to
values comparable with those from the LRMS device.
The RT values, HRMS m/z values, LRMS spectra, and ICLU simulation results for each organic sulfur compound form an identification
‘fingerprint’. The interpretation of these experimental data, with supporting use of fragmentation rules, allow the giving
of a provisional name and structure to the ‘suspect’. In this study and in environmental surveys of micropollutants in general,
the compounds suspected of anthropogenic or natural origin occur at low levels in complex mixtures. Therefore, no bulk amount
of an authentic, pure model substance for the suspect is available quite often. The most probable name and structure from
the fingerprint data are very useful in guiding the preparation of the model substance for a conclusive identification. Similarly,
the unknown criminal can be identified in advance by forensic science and his fingerprint, DNA, etc. as registered before
the arrest. The analogy can be found in the literature and CAS register of organic polysulfides, which in great part consists
of the results of sensitive mixture analysis methods.
Conclusions Sediment of the Eastern Gulf of Finland is over large areas anaerobic, as indicated by the existence of novel, non-oxygenated
sulfur organic microcontaminants. These substances were most abundant in anoxic and saline, deep bottom regions, and, in addition,
in one coastal area near industrial discharges. This occurrence, and also the limited information about sulfur organic compounds
in scientific literature, is considered evidence for the dominantly natural processes in their formation.
Recommendations and Perspectives The importance and necessity of investigating the sulfur organic compounds in the bottom sediments, result from the fact that
their presence can be an indicator of stable anaerobic processes. Similarly, the oxygen disappearance (anoxia) in the marine
water, due to a high concentration of the sulfate ions and relatively high content of organic matter, is practically always
connected with the appearance of hydrogen sulfide and sulfides. The generation of sulfur organic compounds precedes the formation
of the new, or expansion of the existing anaerobic (‘hydrogen sulfide’) zones, which lead to such environmental disasters
as mass destruction of hydrobionts. Many organic compounds of sulfur, including sulfides and polysulfides, are toxic to the
aquatic organisms. Therefore, in addition to the danger of mass wholesale deaths of marine fauna in the bottom sediments region,
there exists a probability of secondary pollution of the water thickness as well, due to the entry of those substances from
bottom sediments in the water when the environmental conditions are changed (stormy weather, floods, geological activity of
the earth’s crust, etc.). 相似文献
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