LOS ANGELES (CBS/WVLT) -- As illnesses related to vaping rise across the country, consumers seek answers to possible causes.
Just in Tennessee alone, there have been 39 vaping-related illnesses as of Oct. 3.
Earlier in the year, a Knoxville man claimed he nearly lost his life due to vaping, and an East Tennessee teen was flown to an area hospital due to vape-related issues.
CBS News Correspondent Carter Evans went undercover to get an inside look at the vape black market in California. Evans infiltrated a warehouse where many people were gathered selling and using reportedly unregulated vape cartridges.
Without regulation, there's no way to know exactly what's in them, and when it comes to teens and kids, vaping tools are easy to hide.
Evans said while at the warehouse, everyone claimed to have pure products, and in places like that, people will buy unregulated cartridges in bulk and resell them nationwide.
The only sure way to know what materials are in black market cartridges is to consult testing labs, CBS said.
CBS News talked to the CEO of Bel Costa Labs, Myron Ronay, and brought vapes purchased on the black market to test them.
Ronay said labs have seen "a slew of pesticides" in vapes found in the black market.
Evans said the vapes they bought on the black market and tested failed for a total of five pesticides, including one called myclobutanil. When that particular pesticide is heated, CBS reported, you get hydrogen cyanide.
Ronay said the best way to avoid potential risk is to shop legal. "If you're in a state that doesn't have legal cannabis, don't buy it," he added.
CBS reported that a large number of vaping-related illnesses appear to be associated with black market THC cartridges.
None of the illnesses reported in Tennessee have been linked to any particular type of cartridge.
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