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Marijuana breathalyzer developed in Pittsburgh could be revolutionary

PITTSBURGH — Marijuana is a hot topic in our state right now. The medical programs are up and running, and Gov. Tom Wolf supports a move to legalize recreational marijuana.

But the latest advancement is a tool to help police make sure people aren't driving while on marijuana.

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Channel 11’s Peggy Finnegan talked to researchers at Pitt who are working on a new marijuana breathalyzer.

The small device, made on a 3D printer, could be the key to keeping you and your family safe.

Researchers from Pitt's chemistry and engineering departments are behind the portable marijuana breathalyzer. A potentially game-changing tool that police currently don't have out on the roads.

They've tested it on one person, and it worked. But, because of federal regulations, they now have to test it with a machine blowing the THC, the active ingredient in marijuana.


Pennsylvania's legal threshold is one nanogram per milliliter of THC in someone's system, a measurement officers can only get from a blood test currently.

“I think this device is gonna take away that guessing. So you don’t just rely on human observation, but there will also be some scientific data to support that observation,” Alex Star, PhD, professor of chemistry at the University of Pittsburgh, said.

In Pennsylvania, the number of crashes related to all drugs has gone up every year over the past five years, according to PennDOT.

In states, like Colorado, where recreational marijuana is legal, deadly crashes have nearly doubled, and with Pennsylvania considering legalizing recreational marijuana, police are behind the device.

“It would be a good tool for law enforcement to have,” Ross police Sgt. Brian Kohlhepp said.

This device is just one of several in testing right now. The Pitt researchers say theirs is different because of its size, its lower cost and its flexibility.

“We can swap all these cartridges to make different. If you want to do alcohol testing versus THC, you just really swap the mouthpiece and move forward,” Ervin Sejdic, PhD, associate professor at the University of Pittsburgh’s Swanson School of Engineering, said.

The next step is more testing - and more testing with people is something that could take months for federal approval, but the researchers say it's important and worth all the work.

“We were more working on this to make the roads safer than anything else. Because any level of impairment is dangerous, not just to the driver but to all of us,” Sejdic said.

The researchers say this will lead to more studies as to how much THC a person can have in their system before officially being “impaired.” Experts agree there is very little research nationwide on THC levels, and the hope is one day to have a legal limit like we have a blood alcohol limit.