Safe and unsafe spaces: Non-fatal overdose, arrest, and receptive syringe sharing among people who inject drugs in public and semi-public spaces in Baltimore City.

The spaces in which drug use occurs constitutes a key aspect of the "risk environment" of people who inject drugs (PWID). We aimed to add nuance to the characterization of "safe" and "unsafe" spaces in PWID's environments to further understand how these spaces amplify the risk of morbidities associated with injection drug use. PWID were recruited through the Baltimore City syringe service program and through peer referral. Participants completed a socio-behavioral survey. Multivariable logistic regression was used to identify associations between utilization of public, semi-public and private spaces with arrest, non-fatal overdose, and receptive syringe sharing. The sample of PWID (N = 283) was mostly 45 years and older (54%), male (69%), Black (55%), and heroin users (96%). Compared to PWID who primarily used private settings, the adjusted odds of recent overdose were greater among PWID who mostly used semi-public and public locations to inject drugs. We also found independent associations between arrest and semi-public spaces, and between receptive syringe sharing and public spaces (all p < 0.05). This study highlights the need for safe spaces where PWID can reduce their risk of overdose, likelihood of arrest and blood-borne diseases, and the dual potential of the environment in promoting health and risk.