"Regardless of what led these individuals to become drug checkers, most appeared to be motivated by altruism and the desire to increase safety and minimize risks associated with others’ drug consumption. We describe their efforts in terms of altruism not only because they act in a selfless manner and donate their time and services, but also because unlike many other volunteers, drug checkers also risk arrest by handling illegal drugs, in order to promote the safety of others. Thus, they essentially place themselves under legal risk to help protect others.
"Many checkers mentioned the desire to educate the public about the importance of drug checking as there is a high prevalence of adulterated drugs in North American drug markets. Desire to educate was often two-fold—to directly educate those about to consume a specific drug (typically through the participants testing drugs in front of the individuals providing them), and to educate PWUD more broadly. Even participants who only tested for themselves often disseminated results, publicly, on social media, in order to inform harm reduction efforts for others. The work of drug checkers is driven primarily by the idea that drug checking allows PWUD to be more aware of the actual contents of the substance they intend to consume, so they believe checking reduces the risk of consuming an unknown substance which could produce untoward or unpleasant side effects."
Palamar, J. J., Acosta, P., Sutherland, R., Shedlin, M. G., & Barratt, M. J. (2019). Adulterants and altruism: A qualitative investigation of "drug checkers" in North America. The International journal on drug policy, 74, 160–169. doi.org/10.1016/j.drugpo.2019.09.017