PMID- 18054787
OWN - NLM
STAT- MEDLINE
DCOM- 20080422
LR  - 20131121
IS  - 0021-9673 (Print)
IS  - 0021-9673 (Linking)
VI  - 1178
IP  - 1-2
DP  - 2008 Jan 18
TI  - Analysis of benzene, toluene, ethylbenzene, xylenes and n-aldehydes in melted 
      snow water via solid-phase dynamic extraction combined with gas 
      chromatography/mass spectrometry.
PG  - 178-86
AB  - The present study describes a method based on headspace-solid-phase dynamic 
      extraction (HS-SPDE) followed by GC/MS for the qualitative and quantitative 
      analysis of benzene, toluene, ethylbenzene, o-, m- and p-xylene (BTEX), and 
      n-aldehydes (C(6)-C(10)) in water. To enhance the extraction capability of the 
      HS-SPDE a new cooling device was tested that controls the temperature of the SPDE 
      needle during extraction. Extraction and desorption parameters such as the number 
      of extraction cycles, extraction temperature, desorption volume and desorption 
      flow rate have been optimized. Detection limits for BTEX ranged from 19 ng/L 
      (benzene) to 30 ng/L (m/p-xylene), while those for n-aldehydes ranged from 21 
      ng/L (n-heptanal) to 63 ng/L (n-hexanal). At a concentration level of 2 microg/L, 
      the relative standard deviations (RSDs) for BTEX ranged from 3.9% (benzene) to 
      15.3% (ethylbenzene), while RSDs for n-aldehydes were between 6.1% (n-octanal) 
      and 16.5% (n-hexanal) (n=7). Best results were obtained when the analyzed water 
      samples were heated to 50 degrees C. At a water temperature of 70 degrees C GC 
      responses decreased for all analyzed compounds. At a defined water temperature, a 
      significant improvement of the GC response was achieved by cooling of the SPDE 
      fiber during water extraction in comparison to an extraction keeping the fiber at 
      room temperature. Evaluating the extraction cycles, for BTEX, the sensitivity was 
      almost similar using 20, 40 and 60 extraction cycles. In contrast, the highest GC 
      responses for n-aldehydes were achieved by the use of 60 extraction cycles. 
      Optimizing the desorption parameters, best results were achieved using the 
      smallest technical available desorption volume of 500 microL and the highest 
      technical desorption flow rate of 50 microL/s. The method was applied to the 
      analysis of melted snow samples taken from the Jungfraujoch, Switzerland (3580 m 
      asl), revealing the presence of BTEX and aldehydes in snow.
FAU - Sieg, Karsten
AU  - Sieg K
AD  - Institute of Atmospheric and Environmental Sciences, Department of Analytical 
      Environmental Chemistry, Johann Wolfgang Goethe-University Frankfurt/Main, 
      Altenhoferallee 1, 60438 Frankfurt am Main, Germany. k.sieg@iau.uni-frankfurt.de
FAU - Fries, Elke
AU  - Fries E
FAU - Puttmann, Wilhelm
AU  - Puttmann W
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20071117
PL  - Netherlands
TA  - J Chromatogr A
JT  - Journal of chromatography. A
JID - 9318488
RN  - 0 (Benzene Derivatives)
RN  - 0 (Water Pollutants, Chemical)
RN  - 0 (Xylenes)
RN  - 059QF0KO0R (Water)
RN  - 3FPU23BG52 (Toluene)
RN  - J64922108F (Benzene)
RN  - L5I45M5G0O (ethylbenzene)
SB  - IM
MH  - Benzene/*analysis/isolation & purification
MH  - Benzene Derivatives/*analysis/isolation & purification
MH  - Gas Chromatography-Mass Spectrometry/*methods
MH  - Snow/*chemistry
MH  - Solid Phase Extraction/*methods
MH  - Toluene/*analysis/isolation & purification
MH  - Water/chemistry
MH  - Water Pollutants, Chemical/analysis
MH  - Xylenes/*analysis/isolation & purification
EDAT- 2007/12/07 09:00
MHDA- 2008/04/23 09:00
CRDT- 2007/12/07 09:00
PHST- 2007/02/22 00:00 [received]
PHST- 2007/11/05 00:00 [revised]
PHST- 2007/11/12 00:00 [accepted]
PHST- 2007/12/07 09:00 [pubmed]
PHST- 2008/04/23 09:00 [medline]
PHST- 2007/12/07 09:00 [entrez]
AID - S0021-9673(07)01957-7 [pii]
AID - 10.1016/j.chroma.2007.11.025 [doi]
PST - ppublish
SO  - J Chromatogr A. 2008 Jan 18;1178(1-2):178-86. doi: 10.1016/j.chroma.2007.11.025. 
      Epub 2007 Nov 17.