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Environ Sci Technol

Title:		Gas-phase chemistry of (alpha-terpineol with ozone and OH radical: rate constants and products
Author(s):		Wells JR;
Address:		"Exposure Assessment Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, West Virginia 26505, USA. ozw0@cdc.gov"
Journal Title:		Environ Sci Technol
Year:		2005
Volume:		39
Issue:		18
Page Number:		6937 - 6943
DOI:		10.1021/es0481676
ISSN/ISBN:		0013-936X (Print) 0013-936X (Linking)
Abstract:		"A bimolecular rate constant, kOH+alpha-terpineol, of (1.9 +/- 0.5) x 10(-10) cm3 molecule(-1) s(-1) was measured using gas chromatography/mass spectrometry and the relative rate technique for the reaction of the hydroxyl radical (OH) with alpha-terpineol (1-methyl-4-isopropyl-1-cyclohexen-8-ol) at (297 +/- 3) K and 1 atm total pressure. Additionally, a bimolecular rate constant, kO3+alpha-terpineol, of (3.0 +/- 0.2) x 10(-16) cm3 molecule(-1) s(-1) was measured by monitoring the first order decrease in ozone concentration as a function of excess alpha-terpineol. To better understand alpha-terpineol's gas-phase transformation in the indoor environment, the products of the alpha-terpineol + OH and alpha-terpineol + 03 reactions were also investigated. The positively identified alpha-terpineol/OH reaction products were acetone, ethanedial (glyoxal, HC(=O)C(=O)H), and 2-oxopropanal (methyl glyoxal, CH3C(=O)C(=O)H). The positively identified alpha-terpineol/O3 reaction product was 2-oxopropanal (methyl glyoxal, CH3C(=O)C(=O)H). The use of derivatizing agents O-(2,3,4,5,6-pentalfluorobenzyl)hydroxylamine (PFBHA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) clearly indicated that several other reaction products were formed. The elucidation of these other reaction products was facilitated by mass spectrometry of the derivatized reaction products coupled with plausible alpha-terpineol/OH and alpha-terpineol/O3 reaction mechanisms based on previously published volatile organic compound/ OH and volatile organic compound/O3 gas-phase reaction mechanisms"
Keywords:		"Air Pollutants Cyclohexane Monoterpenes Cyclohexenes Environmental Monitoring/*methods Gas Chromatography-Mass Spectrometry Hydrogen/analysis Hydroxides/analysis Hydroxyl Radical/*analysis Hydroxylamines/analysis Inorganic Chemicals Kinetics Models, Chemi;"
Notes:		"MedlineWells, J R eng 2005/10/06 Environ Sci Technol. 2005 Sep 15; 39(18):6937-43. doi: 10.1021/es0481676"