Hair analysis for driving licence in cocaine and heroin users. An epidemiological study.

Diagnosis of drug exposure is strongly supported by analysis of hair samples. In the province of Brescia, Italy, for regranting driving license to drug addicts or occasional abusers, a control programme was adopted including analysis of illicit drugs in two hair segments (0-3 and 3-6 cm) and in urine. From January 1998 to April 1999, upon request of the Local Medical Commission, 697 hair samples were tested in our laboratory. One hundred and eighty subjects resulted positive in hair for one or two of the controlled drug classes (73.3% for cocaine, 10% for opiates, 16.7% for both). Positive subjects were classified by residence, age, sex and license category. Seventy-two subjects were called back after 6-12 months and submitted to a second hair and urine analysis: in 34 cases the result of the first analysis was confirmed (19 negatives, 15 positives for one or both drug classes). Another 37 cases tested positive at the first control and negative at the second, suggesting the hypothesis that a strict control may have a significant deterrent function. The high percentage of negative results at the second control may be explained by the prevalence of cocaine users in the examined population. Our results allow us to conclude that the strict application of control rules lead to a decrease of social risk behaviours.

Gas chromatographic/electron impact mass spectrometric selective confirmatory analysis of clenbuterol in human and bovine urine.

A method for the confirmatory analysis of clenbuterol in human and bovine urine was developed. After a double washing of the acidified sample with tert-butyl methyl ether (only for bovine urine), and a solid-phase extraction with Bond-Elut Certify columns, derivatization was performed with trimethylboroxine. The extract was then analysed by gas chromatography/electron impact mass spectrometry. The advantages of the methylboronate derivative with respect to other derivatives are discussed in terms of chromatographic properties and, above all, of specificity of the electron impact mass spectrum. The method was successfully used for the confirmatory analyses of clenbuterol during the XXV Olympic Games of Barcelona.

Determination of clenbuterol in urine as its cyclic boronate derivative by gas chromatography-mass spectrometry.

A rapid and reliable gas chromatographic-mass spectrometric method for the determination of clenbuterol in urine is described. Penbutolol was used as internal standard. Four derivatization procedures have been tested, of which 1-butaneboronic acid gave the best results. The method includes extraction of the alkalinized urine (3 ml) with tert.-butyl methyl ether-n-butanol (9:1), derivatization with 1-butaneboronic acid (15 min at room temperature), and analysis in the selected-ion monitoring mode of the derivatives of clenbuterol at m/z 243, 327 and 342 and of penbutolol at m/z 342 and 357. The detection limit is 0.5 ng/ml and the recovery better than 90%.