The analysis of the keratin matrix as a new tool to evaluate the epidemiology of drug use in Perugia (Italy): a cross sectional study

Background: Drugs and their metabolites can be incorporated into hair, so hair drug testing has become an alternative and complementary method to assess the extent of drug abuse. The aim of our study was to use hair samples to reconstruct the epidemiology of illicit substances used in Perugia. Methods: We conducted a cross-sectional study from May to July 2012 asking hairdressers in Perugia to collect hair samples and to compile a worksheet for each one. The samples were analysed in laboratory: the extraction of basic substances was performed adding methanol; the extraction of acid substances was obtained adding NAOH. After derivatisation, 1 mu l of each solution was analysed through gas chromatography/mass spectrometry. The data were organised in a database and processed using R version 3.2.2. Results: We collected 238 samples. The most detected drugs were: THC-TMS identified in 15 samples, MDMA in 9, Beg-TMS in 8. There was a statistically significant difference in drug use between the city centre (23,36%) and the suburbs (5,34%). Age and sex did not represent influencing factors. The substance with the highest concentration in the keratin matrix was ketamine (9834,86 ng/100 mg of hair). Conclusion: The use of keratin matrix offered significant advantages in the toxicological analysis compared to conventional biological matrices and permitted us to investigate the situation in Perugia where the increased market for illicit drugs has caused a constant rise in drug addiction. However, because this method presented certain limitations only the simultaneous use of keratin matrix and other traditional indicators, could furnish more precise information.