Peace, love, unity, respect… and anti-cannibalism. Such a revised credo for ravers may follow a new study that found many ecstasy users are inadvertently ingesting novel psychoactive substances, known as “bath salts,” which in some cases trigger violent behavior.

Of 48 party-going, life-time ecstasy users that provided hair samples, half tested positive for bath salts (synthetic cathinones), researchers reported. Of the 34 people who said on a survey that they believed they had never taken bath salts, 14 (about 41 percent) tested positive for the psychoactive substances.

“While we cannot completely rule out dishonest responses (e.g., underreporting “bath salt” use), our results suggest that many ecstasy users are unintentionally or unknowingly using synthetic cathinones and/or other [novel psychoactive substances],” the authors wrote in the journal Drug and Alcohol Dependence.

The finding suggests that ecstasy laced with bath salts may be an unappreciated health risk that could help explain recent doubling in ecstasy-related emergency room visits—from 4,460 in 2005 to 10,176 in 2011. The scale of the potential problem is driven home by data from 2012 suggesting that nearly 13 percent of young adults (aged 18 to 25) reported trying ecstasy at least once.

For the study, researchers surveyed 679 nightclub and festival attendees in New York City from July to September of 2015. Of those that identified as life-time users of ecstasy—also known as Molly or MDMA (3,4-methylenedioxy- methamphetamine)—48 were able to give adequate hair samples for testing. (Some men wanted to give samples but didn’t have long enough hair to provide a sample around 10 centimeters long). Researchers assessed the hairs’ drug content using ultra-high performance liquid chromatography–tandem mass spectrometry. And the researchers reasoned that the hair samples could reveal drugs taken up to a year prior to sampling, based on the normal growth rate of hair.

Despite the study revealing that many of the ecstasy users had taken bath salts, researchers reported that at the time of the survey, many participants laughed at the idea and said things such as “I don't use bath salts; I'm not a zombie who eats people's faces.”

The zombie reference goes back to a 2012 case in which a Miami man ate a homeless man’s face. The attacker was thought to have been on bath salts, but later tests suggested that he was not.

Drug and Alcohol Dependence, 2015. DOI: 10.1016/j.drugalcdep.2016.02.001 (About DOIs).