NCJ Number
134443
Journal
Journal of Forensic Sciences Volume: 37 Issue: 1 Dated: (January 1992) Pages: 72-76
Date Published
1992
Length
5 pages
Annotation
To validate data on tobacco use, the authors investigated the use of hair samples for quantifying nicotine and cotinine by gas chromatography/mass spectrometry.
Abstract
Hair was collected from 22 nonsmokers and 42 smokers, cut close to the scalp at the back of the head. Since the influence of environmental exposure was being assessed, hair samples were not washed. Each sample was homogenizated in 3 mL of 1N sodium hydroxide for 1 hour at 100 degrees Centigrade. Drugs were extracted using 5 mL of diethyl ether in the presence of ketamine as an internal standard. They were separated on a 12-m BP-5 capillary column and detected using selected ion monitoring. In the hair of nonsmokers, nicotine content ranged from 0.06 to 1.82 ng/mg and cotinine from 0.01 to 0.13 ng/mg. There was significantly more nicotine in the hair of smokers than nonsmokers, with a nicotine concentration range from 0.91 to 33.89 ng/mg and a cotinine range from 0.09 to 4.99 ng/mg. It was possible to determine a nicotine cutoff value of 2 ng/mg of hair for distinguishing smokers from nonsmokers using the unwashed hair samples. In the nonsmoker population, it was possible to differentiate passive smokers from other nonsmokers. The nicotine content was over 0.5 ng/mg in the group of passive smokers and lower in nonexposed nonsmokers. The presence of varying amounts of nicotine in passive smokers' hair can be explained by the atmospheric deposition of smoke which is rich in nicotine. The presence of cotinine is less easily explained, since cotinine is only produced in vivo. Testing human hair for nicotine offers the possibility of revealing an individual's history of drug exposure. 6 references, 2 tables, and 2 figures (Author abstract modified)