Drug analysis of residual content of used syringes: A new approach for improving knowledge of injected drugs and drug user practices.

Background Since their inception, harm reduction services, including needle exchange programs, have aimed to improve and update knowledge about illicit drug consumption and injection practices in order to assess and regularly revise the effectiveness of preventive strategies. Methods In this paper we describe the development of a scientific approach to obtaining this type of information through analysis of the residual content of used syringes. This was done using a validated liquid chromatography method with mass spectrometry detection to identify different molecules. Used syringes were collected from automatic injection kit dispensers at 17 sites in Paris and the surrounding suburbs each month for one year. Results In total, 3489 syringes were collected. No compounds were detected in 245 syringes. Heroin was the most commonly observed compound (42%), followed by cocaine (41%), buprenorphine (29%) and 4-methylethylcathinone (23%). These analyses also showed the increased appearance of 4-methylethylcathinone between the summer and winter of 2012. Conclusions Despite the bias involved in this approach, the method can provide rapid data on patterns of drug consumption for specific time periods and for well-defined locations. This kind of analysis enables the detection of new substances being injected and thus enables harm reduction services to revise and adapt prevention strategies. [ABSTRACT FROM AUTHOR]