"Our findings of a reduction of health problems, are consistent with harm reduction programs for people who inject drugs , including needle exchange programs and supervised injection sites, where they are effective in reducing overall negative health consequences. By providing users with high-quality smoking equipment and reducing the dependence on unsafe equipment, the unintended negative consequences, including exploding pipes, burns, and inhaling brillo fragments, are further reduced."
Prangnell, A., Dong, H., Daly, P. et al. Declining rates of health problems associated with crack smoking during the expansion of crack pipe distribution in Vancouver, Canada. BMC Public Health 17, 163 (2017). doi.org/10.1186/s12889-017-4099-9.