Alcohol in breath and blood: a selected ion flow tube mass spectrometric study

In this paper we compare the amounts of ethanol in breath and in blood afte r ingestion of whisky using analysis by selected ion flow tube mass spectro metry (SIFT-MS). Blood ethanol concentrations were also obtained using stan dard hospital forensic procedures for blood alcohol analyses. We demonstrat e the quantitative nature of SIFT-MS analysis by correlating the observed a lcohol content of the headspace above 5-mL amounts of venous blood and aque ous solution to which known trace amounts of alcohol have been added. This procedure provides a Henry's Law coefficient for ethanol in aqueous solutio n at 298 +/-t 3 K of 209 +/- 7 mol/kg*bar. We also demonstrate that measure ment of the ethanol concentration in the alveolar portion of a single breat h using the SIFT-MS technique gives an accurate measure of blood alcohol an d could obviate the need for blood samples in forensic processing. The stor age performance of breath samples in Mylar bags with a volume greater than 1 L has been shown to maintain the mixture integrity for ethanol but not fo r some other species. Copyright (C) 2001 John Wiley & Sons, Ltd.