NCJ Number
146661
Journal
Journal of Forensic Sciences Volume: 39 Issue: 1 Dated: (January 1994) Pages: 261-265
Date Published
1994
Length
5 pages
Annotation
Ethyl chloride in a blood sample drawn from an individual charged with possession and/or use of toluene was identified as ethanol on three out of six occasions using headspace gas chromatography.
Abstract
The peak matching tolerance (PMT) for ethanol was set at approximately 0.500 minutes. Three test results fell within the PMT for ethanol. The retention time (RT) for these results was 0.44 minutes, and the relative retention time (RRT) was 0.478 minutes. Three test results, however, fell outside the PMT for ethanol. Two had RT's of 0.48 mintues and RRT's of 0.523 minutes, and one had an RT of 0.44 minutes and an RRT of 0.476 minutes. To prevent ethyl chloride from being identified as ethanol, the PMT was changed to approximately 0.500 minutes. Mixture samples containing deionized water, ethyl chloride, and ethanol were tested with the new PMT. Ethyl chloride and ethanol coeluted, forming one peak that was identified as ethanol. Peak areas of the two compounds in mixture were additive and gave falsely elevated ethanol results. The RT of samples was 0.45 minutes, and the RRT was 0.492 minutes. Carrier gas flow rate was decreased, lengthening RT's and RRT's, but this failed to separate the two compounds. 5 references, 1 table, and 2 figures