article_snippet: Colorado's legal marijuana is three times stronger than
article_snippet: Colorado's legal marijuana was a generation ago and is often contaminated with heavy metals, pesticides, fungus and bacteria, a startling chemical analysis of 600 samples has found.
article_snippet: LaFrate's survey of Colorado's marijuana casts doubt on claims that by legalizing the drug for recreational use in 2012, the drug would make the drug safer to consume. '
article_snippet: Colorado only requires marijuana dispensaries to test and advertise the levels of THC - the compound in pot that gets user 'high.'
article_snippet: LaFrate found that Colorado's legal marijuana has THC levels of 18 to 20percent.
article_snippet: Sometimes THC is as high as 30percent.
article_snippet: Marijuana from the 1980s usually had THC levels of less than 10percent - meaning modern pot is two to three times stronger than it was a generation ago.
article_snippet: It's no coincidence that Colorado's marijuana is dramatically stronger and has dramatically lower CBD levels than the pot of yesteryear.
article_snippet: Growers responded to a demand from consumers for more potent pot by breeding varieties with higher levels of THC and less CBD.
article_snippet: Additionally, much of Colorado's marijuana is contaminated with high levels of fungus spores and bacteria.
article_snippet: Colorado's marijuana's not known what levels of those microorganisms are safe for marijuana and more study on the subject is needed, LaFrate says.
article_snippet: LaFrate warned that the marijuana growing industry is getting by on the marijuana growing industry's hippy reputation and that many consumers believe the plants are grown naturally using organic methods - when in fact, that usually is not the case at all.
highlights_snippet: Colorado weed has THC levels of 18 to 20percent - sometime as high as 30percent .
  
highlights_snippet: Marijuana 30 years ago had THC levels of less than 10percent .
  