title: Quantitative determination of n-propane, iso-butane, and n-butane by headspace GC-MS in intoxications by inhalation of lighter fluid.
abstract: This report describes a fully elaborated and validated method for quantitation of the hydrocarbons n-propane, iso-butane, and n-butane in blood samples. The newly developed analytical procedure is suitable for both emergency cases and forensic medicine investigations. Its practical applicability is illustrated with a forensic blood sample after acute inhalative intoxication with lighter fluid; case history and toxicological findings are included. Identification and quantitation of the analytes were performed using static headspace extraction combined with gas chromatography-mass spectrometry. In order to reconcile the large gas volumes injected (0.5 mL) with the narrowbore capillary column and thus achieve preconcentration, cold trapping on a Tenax sorbent followed by flash desorption was applied. Adequate retention and separation were achieved isothermally at 35 degrees C on a thick-film capillary column. Sample preparation was kept to a strict minimum and involved simply adding 2.5 microL of a liquid solution of 1,1,2-trichlorotrifluoroethane in t-butyl-methylether as an internal standard to aliquots of blood in a capped vial. Standards were created by volumetric dilution departing from a gravimetrically prepared calibration gas mixture composed of 0.3% of n-propane, 0.7% of iso-butane, and 0.8% of n-butane in nitrogen. In the forensic blood sample, the following concentrations were measured: 90.0 microg/L for n-propane, 246 microg/L for iso-butane, and 846 microg/L for n-butane.
authors.affiliation: Laboratory of Toxicology, Ghent University, Belgium.
authors.forename: Marie-Paule L A
authors.initials: MP
authors.lastname: Bouche
authors.forename: Willy E
authors.initials: WE
authors.lastname: Lambert
authors.forename: Jan F P
authors.initials: JF
authors.lastname: Van Bocxlaer
authors.forename: Michel H
authors.initials: MH
authors.lastname: Piette
authors.forename: André P
authors.initials: AP
authors.lastname: De Leenheer
mesh_terms: D000280:Administration, Inhalation; D002073:Butanes / Q000097:blood* / Q000506:poisoning*; D002138:Calibration; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007202:Indicators and Reagents; D011407:Propane / Q000097:blood* / Q000506:poisoning*; D012015:Reference Standards; D015203:Reproducibility of Results; D019966:Substance-Related Disorders / Q000097:blood*
chemical_list: D002073:Butanes; D007202:Indicators and Reagents; C046888:butane; D011407:Propane