Puff piece

A robot is helping to expose vaping's health risks.
Illustrated by
Frank Harris

In September 2019, the Centers for Disease Control and Prevention reported an outbreak of severe lung disease among patients with something in common: They all vaped regularly. Today, more than 2,500 cases of vaping-associated lung illness have occurred in the United States, along with dozens of deaths.

But scientists have yet to fully determine how e-cigarettes and other vaping devices threaten health. With hundreds of different products with an array of ingredients on the market, any number of culprits could play a role.

Researchers now have a new partner helping them get to the bottom of the mystery: A vaping robot, devised by the University of Pittsburgh’s Kambez Hajipouran Benam, a DPhil associate professor of medicine.

The tabletop system mimics inhalation while simulating the conditions inside the human body to measure what people are drawing in when they take a puff from an e-cigarette. Benam’s team can program the robot to match the breathing patterns of people of different ages or those with asthma and other lung conditions.

“We are concerned that vaping is seen as a completely safe thing to do, especially among young people,” Benam says. For adults looking to quit smoking cigarettes, it may present a less harmful alternative. “But when someone in middle school or high school thinks, ‘Oh, it’s safe, so I can try it,’ that is where the problem emerges.”

The robot, which the journal Nature featured in a roundup of research highlights in 2021, offers the chance to study what vaping introduces into the lungs without the time and cost needed to run clinical trials. It can also help researchers keep up as new products, flavors and ingredients hit shelves, some attempting to evade new FDA regulations.

“We want to use the robot to generate the data much more quickly than any other platform,” Benam says. “We will be able to test tens or even hundreds of e-liquids, so people will have a better understanding of the potential for toxicity.”

When the CDC announced the rash of vaping-associated lung illness, the agency linked hospitalizations to an additive called vitamin E acetate. The compound, commonly found in hand lotions and many foods, is used in some vaping liquids, especially those containing THC or other cannabinoids. But it’s not certain how exactly its presence leads to lung damage.

Benam suspects part of the answer lies in the size and quantity of particles drawn into the lungs when vaping. Even a small amount of vitamin E acetate in e-liquid, the robot has shown, dramatically increases the total number of particles, especially very small ones, that end up in the lungs.

Further: “The very small particles can make it deeper into the lungs, and they’re more likely to coat the inner surface of your respiratory tree,” Benam says. “They’re more likely to even penetrate into your bloodstream.”

In a paper published in the journal Respiratory Research in April, Benam used the robot to find that e-cigarette juices containing menthol also generate a greater number of toxic microparticles than those without the mint flavoring. An accompanying analysis of patient records revealed that menthol vapers took shallower breaths and had poorer lung function than other vapers.  

The robotic system—called the Human Vaping Mimetic Real-time Particle Analyzer—uses a finely regulated vacuum pump to draw in vapor from an e-cigarette, while a diluting component adds filtered air (since vape users aren’t breathing in a vapor puff alone). Two air-tight syringes, programmed to simulate the flow rate of breathing, inhale and exhale. An exposure chamber senses and controls the robot’s “body” temperature, humidity and gas levels. With all these factors taken into account, a laser sensor measures the size and number of particles breathed in.

“Basically whatever breathing profile you want, whether it’s restrictive or obstructive or normal breathing, you can customize it to that,” says Rachel Bogdanoff, a research technician in the lab.

In a related, FDA-funded project, Benam’s team is engineering a “next-generation organomimetic human lung system” that, combined with the vaping robot, could show the effects of these products on living cells. In the meantime, the team is looking to confirm their findings through clinical validation and retrospective analysis.

Benam notes that the project brings together engineering, lung pathobiology, breathing mechanics and inhalation toxicology. “The beauty of bringing multiple disciplines together is that you come up with creative solutions for a growing or emerging problem.”