Mice exposed to aerosols generated from both the older box Mod e-cigarettes and JUUL e-cigarettes developed changes in pulmonary function, but did not develop changes in heart rate or blood pressure, according to a study was posted online in the Abstract Issue of the American Journal of Respiratory and Critical Care Medicine 

The researchers conducted the study because e-cigarette use is rising, especially in young never-smoker adults and teens.  Their lab at the University of California San Diego (UCSD), led by Laura E. Crotty Alexander, MD, is focused on understanding the health effects of e-cigarettes, and ensures that they are up to date on the newest and most popular vaping devices. With the release of JUUL, the scientists wanted to research the health effects, if any, these new devices would have and compare them to previous generations of e-cigarettes.

To answer these questions, study author John Shin, clinical research associate at UCSD, and colleagues exposed mice daily for three months to either Mod or JUUL (Mint and Mango) e-cigarette aerosols.  For Mod exposures, the mice inhaled e-cigarette aerosols with nicotine (6 mg/ml), no nicotine or air for one hour daily.  For JUULs, mice inhaled aerosols (59 mg/ml nicotine) for 20 minutes three times a day.  Mice underwent lung physiology testing at the completion of the study.

“Our findings suggest that e-cigarettes affect lung physiology by altering airway resistance and lung compliance,” said Shin. “These data confirm that breathing in a cloud of chemicals via vaping will likely cause lung disease in the long run.”

The authors noted: “For both JUUL and Mod e-cigarette inhalation challenges, mice exposed to e-cigarette aerosols chronically had significant differences in total airway resistance and total lung compliance.  Mice exposed to Mod nicotine-containing aerosols developed increased airway resistance in response to methacholine challenge.  Cardiovascular measures of heart rate, heart rate variability and blood pressure were unchanged in all groups.”

In people, the methacholine challenge involves inhaling a dose of the chemical methacholine, which slightly narrows the airways and shows how reactive or responsive the person’s lungs are to things in the environment.  The test is often used to help diagnose asthma and other respiratory ailments.

“The significant effects of e-cigarette aerosol inhalation on lung mechanics suggest that  chronic inhalation of either JUUL or MOD e-cigarette vapor adversely alters pulmonary physiology,” said Shin. “Future studies with longer exposures and higher levels of aerosol challenge are needed to define the chronic effects of e-cigarettes on pulmonary and cardiovascular physiology.”

  1. Abstract #14602.  Chronic Inhalation of E-cigarette Vapor From JUUL and Mod Devices Alters Lung Compliance and Airway Resistance but Does Not Alter Heart Rate, Heart Rate Variability or Blood Pressure.