We're old enough to remember rumors of razor blades in apples and candy bars laced with cyanide.

We're old enough to remember rumors of razor blades in apples and candy bars laced with cyanide.

This year's scare involves the dangerous synthetic opioid fentanyl finding its way into trick-or-treat bags.

This year's scare involves the dangerous synthetic opioid fentanyl finding its way into trick-or-treat bags.

And in a surprise twist, unlike most Halloween candy panics, this one at least has its origins in reality.

And in a surprise twist, unlike most Halloween candy panics, this one at least has its origins in reality.

Back in August, the Drug Enforcement Administration issued a warning about brightly colored fentanyl pills discovered in 26 states.

They called it "rainbow fentanyl" and said it could be part of an effort to lure kids and young adults into addiction.

Then came reports of police officers' finding 15,000 rainbow fentanyl pills stuffed inside a Lego container in New York, and 12,000 more hidden in candy boxes at Los Angeles International Airport.

While none of these cases involved Halloween, and law enforcement agencies never suggested a connection, it nonetheless stoked nationwide chatter about drug dealers slipping candy-colored pills to trick-or-treaters.

Members of the U.S. Senate soon hopped on board. Earlier this month, 12 Republican senators released a public service announcement about rainbow fentanyl and Halloween.