Atmospheric Chemistry Program Seminar

Non-Targeted Chemical Characterization of Waterpipe Tobacco Smoke by GC-MS and LC-MS by Andrew Jensen,
ANYL 1st year student
"As smoking waterpipes becomes more popular, it becomes necessary to understand the chemical composition of waterpipe tobacco smoke (WTS) and its impacts on human health. Current studies target known components of cigarette smoke, but no current studies acknowledge the possible differences due to the tobacco product and heating profile. The tobacco product, shisha, is made up of tobacco leaves coated in syrup which itself is about one-third glycerol. The shisha is then heated using charcoal, producing larger pyrolysis products. The resulting smoke generated from these constituents can be divided into particulate matter (PM) and vapor. Each fraction may contribute differently to smoke toxicity, making it important to understand the chemical contributions of each constituent. These constituents were studied using gas and liquid chromatography tandem mass spectrometry with a non-targeted approach.
A semi-quantitative comparison of the chromatograms allows for the identification of the sources and sinks of certain compounds in WTS. The GC-MS chromatograms of the shisha, bowl water, PM, and vapor suggest no significant portion of the WTS is trapped by the bowl-water, contrary to popular belief that the water acts as a significant filter. In the LC-MS chromatograms, charcoal alone contributes 10 chromatographic peaks while glycerol, syrup, and shisha each contribute 5, 11, and 32 peaks respectively. A similar comparison of the shisha PM and vapor chromatograms shows that the vapor phase contributes 2 unique peaks while the PM contributes 43 peaks and 11 peaks are shared between the two phases. This study has begun the process of identifying the unique chemical characteristics of the individual sources and sinks of WTS. Toxicity studies can identify WTS fractions of interest, then the unique compounds in these fractions can be isolated by the methods presented in this study."
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Experimental and Theoretical Studies in the Gas Phase Kinetics of Atomic Halides with Methacrolein and Alkyl Bromides by Kyle Mackey, ANYL 1st year student
"In the studies conducted by the Wine Group the rate coefficients of the reactions of bromine radicals with methacrolein and chlorine radicals with several alkyl bromides were determined using the laser flash photolysis - resonance fluorescence technique as a function of temperature and pressure for use in atmospheric modeling and calculations."