Grantee Research Project Results

2005 Progress Report: Aethalometric Liquid Chromatographic Mass Spectrometric Instrument

EPA Grant Number: R831074
Title: Aethalometric Liquid Chromatographic Mass Spectrometric Instrument
Investigators: Dasgupta, Purnendu K.
Institution: Towson University
Current Institution: The University of Texas at Arlington
EPA Project Officer: Chung, Serena
Project Period: September 1, 2003 through December 31, 2007 (Extended to December 31, 2008)
Project Period Covered by this Report: September 1, 2004 through December 31, 2005
Project Amount: $450,000
RFA: Measurement, Modeling, and Analysis Methods for Airborne Carbonaceous Fine Particulate Matter (PM2.5) (2003) RFA Text | Recipients Lists
Research Category: Particulate Matter , Air Quality and Air Toxics , Air

Objective:

The objective of this research project is to fabricate, evaluate, and field test new instrumentation that can provide more information on the speciation of carbonaceous compounds in the atmosphere.

Progress Summary:

A membrane-based denuder coupled particle collector and ion analysis system was built and deployed in Bondville, Illinois. This instrument provides information on all major ionogenic gas composition and corresponding particle anionic compositions plus ammonium. Unlike previous instruments of this type, this instrument determines not only inorganic gases and particles, it also provides measures of acetic, formic, and oxalic acids and the corresponding particle phase organic acid anions, including methanesulfonate. This instrument provides 40 minute time resolution, performs gradient ion chromatography, has a small foot print, and uses a modest sampling rate of 1.5 liters per minute and still attains limits of detection in the low ng/m3 range. Dionex Corporation has licensed marketing rights of the membrane denuder used in this instrument from Texas Tech University (U.S. Patent 6,890,372).

A second copy of the above instrument was deployed in Beltsville, Maryland, for approximately 3 weeks and compared with two commercial monitoring instruments for aerosols and gases (MARGA instruments) being evaluated by the U.S. Environmental Protection Agency.

For a number of high-volume filter samples, the total carbon content was determined by elemental analysis techniques (combustion to CO2), and sequential solvent extraction liquid chromatography-mass spectrometry (LC-MS) was attempted to determine the percent of carbon that could be accounted for. In most cases, more than 50 percent of the carbon was unaccounted for suggesting this will not be a viable technique.

A membrane-based device was developed last year. This microvolume device removes CO2 near-quantitatively from an aqueous stream. This has been commercialized by Dionex Corporation and already has found considerable consumer acceptance.

A size selective multiple wavelength aethalometer has been developed. A 12 element LED-array ranging from 375-855 nm and a 512 element photodiode array are used. The geometry permits both spectral measurement of the particles and the size distribution measurement of the particles.

We have developed a means to classify water-soluble and insoluble carbon based on the ease with which it is oxidized to CO2 by liquid phase radical and photooxidation processes.

Future Activities:

We intend to carry out some work to complete the research on the ability of elemental versus organic carbon to convert NO2 into nitrous acid. The comparison with MARGA instruments will be written up. Efforts toward a movable, self-advancing tape-based size-discriminating multiwavelength aethalometer will continue. Mathematical deconvolution efforts to translate the raw data into particle size will be undertaken. Conversion of NO2 to nitrous acid by soot derived from meaningful participation in field experiments will be sought. Basic research into classifying carbon on solution phase oxidation will continue.

Journal Articles on this Report : 5 Displayed | Download in RIS Format

Publications Views
Other project views:	All 46 publications	22 publications in selected types	All 22 journal articles

Publications
Type	Citation	Project	Document Sources
Journal Article	Dasgupta PK, Li J, Zhang G, Luke WT, McClenny WA, Stutz J, Fried A. Summertime ambient formaldehyde in five U.S. metropolitan areas:Nashville, Atlanta, Houston, Philadelphia, and Tampa. Environmental Science & Technology 2005;39(13):4767-4783.	R831074 (2005) R831074 (Final)	Abstract from PubMed Full-text: ES&T-Full Text HTML Exit Abstract: ES&T-Abstract Exit Other: ES&T-Full Text PDF Exit
Journal Article	Li J, Dasgupta PK, Luke W. Measurement of gaseous and aqueous trace formaldehyde:revisiting the pentanedione reaction and field applications. Analytica Chimica Acta 2005;531(1):51-68.	R831074 (2005) R831074 (Final)	Full-text: Science Direct-Full Text HTML Exit Abstract: Science Direct-Abstract Exit Other: Science Direct-Full Text PDF Exit
Journal Article	Ullah SMR, Williams A, Dasgupta PK. Automated low-pressure carbonate eluent ion chromatography system with postsuppressor carbon dioxide removal for the analysis of atmospheric gases and particles. Aerosol Science and Technology 2005;39(11):1072-1084.	R831074 (2005) R831074 (2006) R831074 (2007) R831074 (Final)	Full-text: Informaworld-Full Text HTML Exit Abstract: Informaworld-Abstract Exit Other: Informaworld-Full Text PDF Exit
Journal Article	Takeuchi M, Rahmat Ullah SM, Dasgupta PK, Collins DR, Williams A. Continuous collection of soluble atmospheric particles with a wetted hydrophilic filter. Analytical Chemistry 2005;77(24):8031-8040.	R831074 (2005) R831074 (2006) R831074 (Final)	Abstract from PubMed Full-text: ACS Publications-Full Text HTML Exit Abstract: ACS Publications-Abstract Exit Other: ACS Publications-Full Text PDF Exit
Journal Article	Ullah SMR, Adams RL, Srinivasan K, Dasgupta PK. Asymmetric membrane-fiber based carbon dioxide removal devices for ion chromatography. Analytical Chemistry 2004;76(23):7084-7093.	R831074 (2005)	Abstract from PubMed Full-text: ACS Publications Full Text Exit Other: ACS Publications PDF Exit

Supplemental Keywords:

aethalometry, ion chromatography, liquid chromatography, carbonaceous particles, atmospheric aerosols, oxidation to CO2, membrane transfer, conductometry,, RFA, Health, Air, Ecosystem Protection/Environmental Exposure & Risk, Scientific Discipline, PHYSICAL ASPECTS, Physical Processes, Risk Assessments, particulate matter, Air Quality, Environmental Chemistry, Engineering, Chemistry, & Physics, Analytical Chemistry, Monitoring/Modeling, Air Pollution Effects, air toxics, Environmental Engineering, Environmental Monitoring, aerosol particles, health effects, molecular markers, particle size, air sampling, gas chromatography, mass spectrometry, carbon particles, emissions, air quality modeling, measurement methods, aethalometric liquid chromatographic mass spectrometry, aersol particles, human exposure, ambient air monitoring, atmospheric particles, thermal desorption, particulate matter mass, air quality model, exposure, ambient particle health effects, carbon aerosols, aerosol analyzers, air quality models, atmospheric particulate matter, particle dispersion, human health effects, human health risk, monitoring of organic particulate matter, air modeling

Relevant Websites:

http://www.depts.ttu.edu/chemistry/faculty/dasgupta/dasgupta.html Exit

Progress and Final Reports:

Original Abstract

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.