Law enforcement officers in Texarkana are seeing an increase in marijuana vaping, a trend that appears to be nationwide.
"We see it everywhere - traffic stops, houses. We did a search on a house where they were making their own by filling empty vape cartridges," said a Texarkana, Texas Police Department narcotics officer who asked that his name not be used.
"They are popular and on the street," said Lt. Scott Megason, of the Texarkana Police Joint Special Operations Unit.
Possession is illegal in both Arkansas and Texas - with the exception of Arkansas Medical Marijuana patients who must have a state registration card.
"The biggest deterrent to anyone should be that it is a felony, even the smallest amount. It's a felony in Texas if it is 4 ounces or above. Do not bring these to Texas. That's what a lot of people are doing, bringing them back from Colorado and California and selling them here," the narcotics officer said.
Possessing any amount over 4 ounces is also a felony in Arkansas, Megason said.
But vaping items, especially those purchased on the black market can also be potentially dangerous for the user's health.
Vaping rapidly gained ground in the past few years among marijuana users as a fast-acting and discreet alternative to smoking the drug. Thirty-three states have legalized marijuana at least for medicinal use, but bootleg vape "carts" - short for cartridges - have cropped up here and elsewhere, selling for roughly $20 to $50 apiece.
"It's a double-edged sword," Megason said "Not knowing what is in some of it, is one of our largest concerns. In some places, there have been reports of fentanyl in it.
"With the Arkansas Medical Marijuana Act, everything grown in Arkansas has to be tracked and tested in a lab. But buying on the street is dangerous. Even with legitimate vapes, you don't always know what chemicals are in them. It's always good to err on the side of caution," Megason said.
Nationwide, authorities have seized at least 510,000 marijuana vape cartridges and arrested more than 120 people in the past two years, according to an Associated Press tally derived from interviews, court records, news accounts and official releases.
A lot of people using are teens or in their early 20s, but police also see people of all ages.
The percentage of THC in vaping cartridges is also much higher than other sources, the narcotics officer said.
"We still have marijuana that comes over the Mexican border. It's over 20 to 30 percent THC," he said. "The marijuana grown in in California and Colorado is more like 70%. The majority of the vape pens that are commercially done are 92 to 94 percent. The high is a whole lot higher."
The lung-illness outbreak has raised alarms about vaping as more than 2,200 people fell ill and at least 47 have died in the past nine months. Health officials have urged people to avoid vaping, particularly black-market products containing THC, which many of the sick said they had used.
Health officials announced last month that vitamin E acetate, sometimes used to thicken vaping fluid, is a "very strong culprit as a cause of the illness."
The Associated Press contributed to this report.