Denver Environmental Health has banned the sale of kratom for human consumption. The decision follows a public health advisory warning individuals not to consume kratom, a popular herbal substance of Southeast Asian origin that’s become more widely available in Colorado over the past few months, issued by the U.S. Food and Drug Administration on November 14. Prior to this alert, reports circulated about more than a dozen deaths associated with, although perhaps not directly attributable to, use of the substance, which is known for its euphoric and pain-relieving effects.