Applying a multiple methods approach to examine spatial and temporal variability in a state's illicit drug market - ABSTRACT The US is currently in the middle of the fourth wave of the opioid overdose crisis. This wave has been characterized by multiple factors. The first is the dominance of fentanyl and related compounds in the illicit drug marketplace. The second factor has been the introduction of adulterants like xylazine that increase the complexity of responding to overdoses and treating opioid use disorder while introducing unique medical problems on its own. Third, overdose deaths are increasingly the result of polypharmacy deaths involving opioids and stimulants. A fourth issue is increasing fatal overdose deaths in urban, BIPOC communities. And finally, as is often the case, the marketplace is experiencing the introduction of novel substances including non- traditional synthetic opioids, cathinone-derived stimulants, synthetic cannabinoids, and prescription neuroleptics, alone or in combination with more readily available illicit drugs. Better information on all of these issues is central to the development of effective responses. We are proposing to gather integrated data on the drugs in circulation in the illicit marketplace through a combined effort to check the drugs of individual people who use drugs (PWUD) and test for drugs in the wastewater stream in the communities where these people live. The study has three aims: (1) expand existing street-based testing of samples from representation samples of PWUD accrued through an adaptive respondent driven approach; (2) develop a robust wastewater sampling and testing system drawing on municipal treatment facilities in cities in Connecticut to determine community levels of fentanyl, xylazine, heroin metabolites, and cocaine and detect novel psychotropic drugs; and (3) integrate the street-based and wastewater data streams to measure the spatial and temporal congruence between the two datasets across cities and within neighborhoods. The relationship of the testing data to data on fatal overdoses with an emphasis on the post-mortem drug testing conducted by the CT Office of the Chief Medical Examiner and non-fatal overdose data from all EMS responses in datasets maintained by the CT Department of Public Health will lead to the development and testing of spatio-temporal models that measure the ability of the drug testing data to detect the drugs associated with clusters of overdoses and to predict overdose patterns. The models, in turn, can influence the development of interventions to reduce the incidence of overdose. We plan to disseminate compiled and curated drug checking and wastewater testing data and model predictions to (i) harm reduction programs that can inform people who use drugs and take broader steps to reduce the negative consequences; (ii) state and local health departments to complement current state agency overdose reporting, (iii) medical professionals such as addiction specialists and emergency room staff who interact with PWUD, (iv) public safety officials, and (v) the media. Beyond Connecticut, this project will be generating evidence to determine the practicality of implementing similar integrated testing systems in other states.
