"Perhaps our most significant finding is that all of this SSP’s success in implementing drug checking was achieved in spite of, rather than thanks to, the legal and policy environment in which it operates. The COVID-19 pandemic made drug checking practically impossible, but only after systematic police violence against participants and threats against staff had already curtailed provision of this harm reduction service. Indeed, it is likely that drug checking could have persisted during the pandemic absent the very real risk of police interference.

"Drug checking, or the use of technology to provide insight into the contents of illicit drug products, is an evidence-based strategy for overdose prevention [10,11,12,13,

"RAD involves a four-step process. First, wearing gloves, SSP staff members wipe or swab used drug paraphernalia received from registered SSP participants. Each individual wipe or swab is then placed into a small paper envelope that is collected in a larger mailing envelope (2). Program staff members administered a deidentified questionnaire simultaneously with paraphernalia sample collection and linked the questionnaire and sample with a unique barcode number.§§ Second, samples are mailed to NIST in accordance with U.S. Postal Service regulations.

"Once OPCs were operating in NYC, local Community Board members and other local leaders were invited to tour the sites and see the services firsthand. This has been a powerful tool to demystify OPCs and educate observers about harm reduction. It was helpful, in terms of building community support, that OnPoint already had strong community relationships developed over more than 20 years of operating an SSP.

"As with any service provided to the public, NYC Health Department viewed community engagement and education as critical to the success of OPCs, particularly given the stigma that substance use providers and participants often face. Prior to implementation, the NYC Health Department conducted general educational briefings with local community groups and leaders in neighborhoods across the city, including those where the OPCs would be located.

"NYC engaged in a series of discussions with local, state, and federal stakeholders to gauge the viability of opening OPCs in the absence of clear authorization. Strong political engagement of local stakeholders—including the New York City Police Department (NYPD), district attorneys, and local elected officials—was critical to not only mitigate risks of local enforcement against OPC operations but also to ensure successful service provision. Education and engagement of city agencies and elected officials have been ongoing since the release of the feasibility report in 2018.

"In 2021, NY State and the USA elected executive branch leaders who publicly supported harm reduction as a public health approach to reducing overdose deaths. In April 2021, the Biden administration explicitly listed “enhancing evidence-based harm reduction efforts” as a drug policy priority for its first year in office, which NYC interpreted as potentially aligned with the concept of OPCs.

"A xylazine-associated death was defined as a positive postmortem xylazine serum toxicology test result in an unintentional, undetermined, or pending intent substance-related death during January 2017–October 2021. Routine postmortem tests were conducted for other substances including fentanyl, fentanyl analogs, cocaine, and naloxone. Xylazine testing is standard in Cook County for suspected drug overdose deaths.

"Xylazine, an alpha-2 receptor agonist, is used in veterinary medicine as a sedative and muscle relaxant; it is not approved for use in humans. However, reports of adulteration of illicit opioids with xylazine have been increasing in the United States (1–3). In humans, xylazine can cause respiratory depression, bradycardia, and hypotension (4).

"In June 2020, the presence of xylazine, a veterinary sedative, was first detected as an active cut in heroin/fentanyl MADDS samples but in very low or trace quantities from 2 sites. By fall 2020, the ratio of xylazine to other active drugs had increased, and by the end of the year, xylazine was identified in 6.3% of MADDS samples (13.4% of fentanyl, 22.2% of heroin) and detected at all sites. At the close of 2020, some samples were found to contain more xylazine than fentanyl (eg, https://DrugsData.org/9661).