Teens who listen to music that mentions marijuana are significantly more likely to use the drug, a new study finds.

The research was based on surveys with 959 ninth-graders.

"Students who listen to music with the most references to marijuana are almost twice as likely to have used the drug than their peers whose musical tastes favor songs less focused on substance use," said University of Pittsburgh School of Medicine researcher Dr. Brian Primack, who led the study.

"Interestingly, we also found that exposure to marijuana in music was not associated with other high-risk behaviors, such as excessive alcohol consumption," Primack said. "This suggests that there is a real link between the marijuana lyrics and marijuana use."

Among the study participants, 12 percent identified themselves as current marijuana users, with 32 percent identifying themselves as having previously tried the substance. The researchers analyzed the content of songs that the students reported listening to.

The average participant listened to 21.8 hours of music per week and heard about 40 marijuana references in music per day.

Researchers controlled for such demographic variables as age, race, gender, parental education and school grades in analyzing the data.

"Although it may be that heavy exposure to music about marijuana causes marijuana smoking, it may also be that those who smoke marijuana seek out music with lyrics related to marijuana," Primack said.

The study, published online by the journal Addiction, was funded by National Institutes of Health, the Robert Wood Johnson Foundation and the Maurice Falk Foundation.