LOS ANGELES (CBSLA) -- The highly-respected Mayo Clinic believes they have found out why some people were getting sick -- and some even dying -- from vaping, formerly sold as a safe and harmless product.
In fact, vaping was first sold as a healthier alternative to actual cigarette smoking.
After studying 17 different biopsies of people who developed lung injuries and problems, they think they are close to understanding the root of the cause.
It was originally believed the problem came from an accumulation of mineral oil, but the Mayo Clinic it is more aligned with the kinds of problems that occur when people breathe in toxic chemical fumes.
Seventy-one percent of the injured patients had vaped with marijuana oils.
CBS2/KCAL9's Nicole Comstock reported about the Mayo Clinic study and asked people for their reaction to it.
Davis Dang says he's been vaping for seven years and has never once gotten sick.
And he told Comstock, he's well aware of what it is he's inhaling and has heard the warnings.
"Propylene glycol, vegetable glycerin, nicotine and the flavoring." Dang says.
He's also well aware of the message doctors across the country have recently been pushing.
"If you don't need to vape, don't start," Dr. Cameron Kaiser of the Riverside County Public Health Office told Comstock.
"I think before they try to start banning everything they should provide proof that it's actually bad for you," Dang says.
Comstock showed four lab samples that showed damaged lung cells. All of the samples came from people who vaped. Their lungs showed chemical-type burns.
Dr. Kaiser told Comstock that what interested him about the study was the finding that 71 percent of the biopsies of people with issues all vaped with marijuana or cannabis oils.
"They may be a big part of the explanation -- they don't appear to be the whole story," Dr. Kaiser says. "They're so unregulated as a whole that we don't really understand what people are getting in there."
He says seven people have been hospitalized in Riverside County with vaping-related lung illnesses.
Across the country, the CDC says 800 people have experienced vaping-related lung injuries -- 12 of those people died.
Dang has his own theory about what could be causing the illnesses and death.
"Could be bad pods that people are making on the black market," Dang says.
He feels bad for legitimate businesses that have seen sales slow after some of the studies that are still in their early stages.
"Small business owners." says Dang, "it's not like big tobacco where it's a corporation."
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