Analysis of drugs in sewage: an approach to assess substance use, applied to a prison setting

The objective of this memo is to present: 

• the method and calculation of uncertainty. (This method involves sampling, analysing, quantifying, calculating and estimating the quantity of metabolites and active molecules present in a volume of sewage over a defined period. However, at each step, numerous parameters should be taken into account to reduce errors in the final estimation of the quantities of drugs used, as far as possible.) 
• the studies conducted in France and European urban areas by the SCORE group which has been coordinating samples in several major EU cities since 2011 
• and its application in the specific context of a university research project initiated in 2015 in prison settings. 

Testing the water is an internationally renowned approach that leads to an objective estimation of illicit drug use in a given population area, varying in size depending on the chosen sampling point.  This method evidently has some biases, and the results obtained are merely a reflection of the situation at a  specific moment in time and does not provide data on the prevalence of use or user profile. However, it has the  advantage of allowing illicit substance use to be mapped, in terms of the quantities used and type of substance, according to different geographical sectors. Comparing these findings with the economic and social data in the regions studied, together with the possibility for monitoring use over time appear to be relevant applications of  this approach, to help manage prevention action and harm reduction measures related to illicit drug use.

The objective of this report is to present an initial feasibility study conducted in three prisons in France, in the specific context of a university research project initiated in 2015 in a prison setting. The first results, together with the difficulties encountered, the limitations and ethical considerations will  be developed in order to generate all of the aspects necessary to understanding and interpreting these types of analyses.