TITLE:
Real-Time Air Monitoring of Trichloroethylene and Tetrachloroethylene Using Mobile TAGA Mass Spectrometry
AUTHORS:
Nicholas S. Karellas, Qingfeng Chen
KEYWORDS:
Environmental; Real-Time Monitoring; Mobile TAGA; TCE and PCE; Ambient Air
JOURNAL NAME:
Journal of Environmental Protection,
Vol.4 No.8A,
August
12,
2013
ABSTRACT: Trichloroethylene
(TCE) is a chlorinated liquid that is commonly used for metal degreasing,
household and industrial dry cleaning, and in paints and glues.
Tetrachloroethylene, also known as perchloroethylene (PCE), is an excellent solvent
for organic materials. PCE is volatile, highly stable, non-flammable and widely
used in dry cleaning. A new method has been developed for measuring TCE and PCE
in ambient air in real-time. Based upon the chemical fingerprinting and
concentration levels, the method was able to isolate the source of the
emissions to the responsible facility. Real-time monitoring was accomplished by
utilizing a low pressure chemical ionization source (LPCI) interfaced to a
tandem mass spectrometer (TAGA). Monitoring the response of specific
parent/daughter ion pairs, the TAGA was used to measure concentrations of TCE
and PCE. By optimizing various TAGA parameters, detection limits (DL) as low as
0.5 μg/m3 was
achieved for TCE and PCE. Unlike methods using cartridge sampling and GC/MS
analysis, this new method provides a real time measurement for a wide range of
TCE and PCE concentrations. This unique method was applied in 2000 and 2002 to
measure TCE emitted from a manufacturer of stainless steel tubing in Eastern Ontario. The maximum half-hour average
concentration of TCE measured downwind of the facility was 1300 μg/m3 and the maximum instantaneous
level was measured at 115,000 μg/m3. The information collected
by the TAGA unit was used by the Standard Development Branch of Ontario
Ministry of the Environment to adopt the half-hour Point of Impingement (POI) standard of TCE to be 36 μg/m3 in 2010. This method
successfully identified and simultaneously measured TCE and PCE during a 2011
air monitoring survey of a hazardous waste disposal and treatment facility in Southern
Ontario.