Determination of BTEX Compounds in Ambient Air Using Solid Phase Microextraction Gas ChromatographyM

1
Determination of BTEX Compounds in Ambient Air
Using Solid Phase Microextraction Gas
Chromatography-Mass Spectrometry
Christopher L. Marcum1 Bert C. Lynn2

• Department of Chemistry, Eastern Kentucky
  University, Richmond, KY
• Department of Chemistry, University of Kentucky,
  Lexington KY

Conclusions
Introduction
Results and Discussion

• Air quality is of paramount importance. Exposure
  to air which contains contaminants can lead to
  major health problems including nervous system
  damage.
• Recently, solid phase microextraction (SPME) has
  been offered as an alternative to traditional air
  sampling techniques for determination of air
  contaminants.
• The purpose of our study is to develop a
  technique for the determination of BTEX compounds
  (benzene, toluene, ethylbenzene, xylenes) in
  ambient indoor air using SPME, coupled with gas
  chromatography/mass spectrometry (GC/MS).
• Evidence also shows a possible link between these
  BTEX contaminants and electronic equipment, such
  as laser printers and copiers.

• SPME proved to be a very simple technique for air
  sampling and, when coupled with GC/MS, was very
  sensitive and selective for volatile organic
  compounds, including BTEX compounds.
• Although concentrations were not determined, the
  chemistry copy room, chemistry office, and
  intellectual property office had the highest
  levels of contamination from BTEX compounds.
• We found no observable link between either the
  presence or the use of a laser printer and an
  increase in BTEX compounds in the air.
• We also were unable to link the presence of a
  copy machine to an increase in BTEX contamination.

Future Work
Experimental Methods

• Air sampling was accomplished through the use of
  a carboxen/PDMS SPME fiber placed in a manual
  holder. Before sampling, each fiber was
  conditioned for 2 hours in a hot GC injection
  port.

The chromatogram (top) is from a SPME fiber
exposed for 6 hours in the chemistry department
copy room. The peaks labeled A-D were identified
as the BTEX compounds shown above. Chromatograms
were obtained from each location and the peak
areas were examined in order to compare the
locations.

• Analysis of other locations, including other
  campus buildings and perhaps some off-campus
  locations
• Use of other traditional air sampling techniques
  to verify SPME results
• Determine the concentration of BTEX compounds in
  each sample location
• Testing of other possible sources of BTEX
  contamination using glove bag techniques

1 Chemistry Copy Room 2 Chemistry Office 3
Intellectual Property Office 4 ASTeCC Copy
Room 5 ASTeCC Conference Room 6 Outside
ASTeCC

• Several locations were sampled across the campus
  of the University of Kentucky, Lexington, KY
• Chemistry Department Copy Room, Chemistry Physics
  
• Building
• Chemistry Department Office, Chemistry-Physics
• Building
• Intellectual Property Office, Advanced Science
  and
• Technology Commercialization Center (ASTeCC)
  
• Building
• Copy/Fax Room, ASTeCC Building
• Conference Room, ASTeCC Building
• Outside the ASTeCC Building

Acknowledgements

• The peak areas for BTEX compounds were much
  greater in the chemistry copy room, chemistry
  office and intellectual property office.

• We are grateful to the Department of Chemistry,
  University of Kentucky REU program, funded by NSF
  and the Air Force ASSURE program for support of
  this work.

• Fibers were transported to and from sample
  locations in clean glass tubes. Each sample
  fiber had an associated trip blank, which was not
  exposed to the air.
• Immediately following sampling, analysis of the
  fibers was carried out via a Varian 3400 4D GC/MS
  equipped with electron ionization and an ion trap
  mass analyzer.
• The effects of a laser printer on air quality
  were determined by enclosing a laser printer in a
  nitrogen filled glove bag and sampling the air in
  the bag while the printer was in several
  configurations off, on without toner, and while
  printing.

1 Nitrogen Only 2 Printer Off 3 Printer
On 4 Printer Printing

• We would also like to thank the University of
  Kentucky Mass Spectrometry Facility and Michael
  Timmons for their assistance with this project. 

• Peak areas for BTEX compounds did not increase
  within an enclosed glove bag when a laser printer
  was introduced, turned on, or printing.