News Rainbow fentanyl passed out on Halloween? Why experts say that’s ‘absolutely ludicrous.’ October 26, 2022October 26, 2022Jordan Mendoza, USA TODAYComments Off on Rainbow fentanyl passed out on Halloween? Why experts say that’s ‘absolutely ludicrous.’ Concerns of the opioid targeting children has expanded to it being handed out while trick-or-treating, but experts don't believe it will happen.