Recreational marijuana has been legalized in four states, but that doesn't mean it's a tested consumer product. Some of those potent buds are covered in fungus while others contain traces of butane, according to an analysis of marijuana in Colorado.
Last May, after people began getting sick from edible marijuana products, the state of Colorado began requiring all products to be tested. Washington has mandated testing too, with a detailed checklist of items to analyze, including potency, contaminants, moisture and microbiology.
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