(WEBMD) — Legal marijuana grown in Colorado is two to three times as potent as what was sold on the black market 30 years ago, according to test results released this week at a scientific meeting in Denver.
But it’s the unexpected contents of Colorado’s recreational marijuana that surprised researchers. Scientists found butane, heavy metals, and fungus in some samples.
“It’s pretty startling just how dirty a lot of this stuff is,” said Andy LaFrate, president and director of research at Charas Scientific, in a news release. “You’ll see a marijuana bud that looks beautiful. And then we run it through a biological assay and we see that it’s covered in fungi.”
Advertisement - story continues below