The state of Michigan has not gotten any reports of adverse effects from THC-infused vapes that have been sold by medical marijuana dispensaries.

The distinction between black-market vapes and those sold at medical marijuana dispensaries is important. The marijuana concentrate in the vapes sold at licensed pot shops has to go through testing both before and after the liquid is put into the vape cartridges, said David Harns, spokesman for the Michigan Marijuana Regulatory Agency.

So the vapes that end up in medical marijuana shops don't have contaminants or dangerous additives that have been found in the bootleg vapes.

The public health crisis from vaping has hit 805 people in 46 states, but 77% of those hit by the lung illness have been using THC-infused vapes, the Centers for Disease Control and Prevention said Friday.

“The latest findings from the investigation into lung injuries associated with e-cigarette use, or vaping, suggest products containing THC play a role in the outbreak,” the CDC reported, adding that 12 deaths have been confirmed in 10 states.

In the 30 days before symptoms began to appear, 77% of the people stricken reported using THC products, while 57% reported using nicotine-based products. THC — or tetrahydrocannabinol — is the psychoactive element in the cannabis plant that provides the "high" for users.

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The CDC has recommended that people refrain from vaping nicotine or marijuana-infused products while they investigate the illnesses, but it has not recommended a ban on the products.

But the states of Michigan, New York and Massachusetts have issued bans on various vaping products. Michigan and New York have banned flavored vapes and Massachusetts is imposing an immediate ban on all vapes.

Michigan’s rules take effect on Oct. 2, although an Upper Peninsula vape shop owner has filed suit against the state’s ban, saying it’s not appropriate to be done by the Michigan Department of Health and Human Services by emergency rules. Marc Slis, owner of 960 Vapor, has also asked for a temporary restraining order in his lawsuit filed in Houghton County Circuit Court to try and ensure that the ban doesn’t take place before a hearing on his lawsuit is held.

Contact Kathleen Gray: 313-223-4430, kgray99@freepress.com or on Twitter @michpoligal.