The density of discarded needles in Montreal: The influence of the environment urban characteristics
The many studies of discarded needles that have been conducted since the 1980s have usually been conducted either to evaluate discarded needle collection programs or to identify the reasons why such programs are used by injection drug users. Most of these studies have been qualitative and do not address the spatial distribution of discarded needles within urban public space. However, a better understanding of the geography of discarded needles is highly relevant to optimizing some parts of such programs, such as where drop boxes should be located. This article is based on an analysis of the geographic position of 13,560 discarded needles collected between 2009 and 2014 in the Centre-Sud neighbourhood of Montreal. Several Tobit regressions were done using the density of discarded needles within a radius of 100 metres as the dependent variable and indicators of the urban environment, such as proximity of needle-collecting programs, police stations, subway stations and the type of streets or the presence of parks, as the independent variables. The strongest explanatory variables for the study period were the presence of alleys and drop boxes.