In May 2012, the nation first caught wind of "bath salts" thanks to the "Miami Cannibal" attack. In the hours after Rudy Eugene chewed the face off homeless man Ronald Poppo near the MacArthur Causeway and was fatally shot by cops, a Miami Police spokesman speculated that the synthetic drug might have driven Eugene's madness.

The only problem is that bath salts were never found in Eugene's body in any postmortem exams. And last week, as scientists presented one of the most comprehensive reviews yet of the drug's effects on the human body, the evidence seems stronger than ever that bath salts aren't likely to cause a craving for human flesh.

"Young people still associate bath salts with cannibalism," Michael Baumann, head of the Designer Drug Research Unit at the National Institute on Drug Abuse, tells Riptide, "despite the fact that there's no truth to the Miami Cannibal's connection to bath salts."

That's not to say the drugs are safe, of course. The research from Baumann and his colleagues -- presented at the Society for Neuroscience's annual gathering in Washington, D.C. -- suggests the drugs act much like cocaine or ecstasy by tweaking the body's production and absorption of dopamine.

Researchers found that many modern versions of the drug are based on synthetic versions of "cathinones" -- a product derived from the khat plant, a popular stimulant chewed in parts of the Middle East.

Dopamine is the same compound the brain releases in small doses when confronted with pleasurable stimulus -- an effect mimed by many drugs. Cocaine, for instance, blocks the body from reabsorbing dopamine so it remains in the system longer; ecstasy, meanwhile, tricks cells into releasing more.

Bath salts use both tricks, the scientists found. Cathinones cause more dopamine to be released, while a compound called MDPV keeps it in the body longer. "The drugs all increase the amount of extra-cellular dopamine in the body, which is what feels good and is also what leads to addiction risks," Baumann says.

That's not the only risk. Just like cocaine, bath salts can cause psychosis and other mental problems with overuse, Baumann says.

Still, nothing in the research suggests cannibalism is among bath salts' physical effects. Not that anti-drug advocates are so eager to advertise that fact; after a big spike in 2011, bath salts use has dropped dramatically. Along with legit research into its dangers, Baumann has no doubt the Eugene story plays a role.

"I do actually think in some ways it scared people away from using the drugs," he says. "We're interested in the truth, of course, but these are also very dangerous drugs that no one should be using."

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