As officials struggle to fight the opioid epidemic that is plaguing the country, some big cities are considering creating "safe injection" sites. Addicts would be able to use their drugs under the watch of medical professionals, and they would be provided clean needles. While no city has submitted a formal plan, the idea is already stirring up controversy.

Dina Fine Maron, Health & Medicine Editor at Scientific American, explains the science behind safe injection sites. Allowing addicts to use drugs under supervision and with clean needles helps to reduce diseases associated with intravenous drug use such as HIV.

While no city in the United States has a "safe injection" site, Fine Maron says existing sites in Europe and Canada have proven to be a success. Data shows that opening these sites helps reduce opioid-related deaths and problems.