Acute Effect of E-Cigarette Inhalation on Mucociliary Clearance in E-Cigarette Users

Area of Science:

• Pulmonary Medicine
• Respiratory Physiology
• Toxicology

Background:

• E-cigarette (EC) use is linked to chronic bronchitic symptoms, potentially due to impaired mucociliary clearance (MCC).
• Limited data exists on the acute and chronic effects of EC inhalation on *in vivo* MCC.

Purpose of the Study:

• To investigate the acute effects of controlled e-cigarette inhalation on *in vivo* mucociliary clearance in young adults.

Main Methods:

• Measured *in vivo* MCC in 5 young adult males using radiolabeled aerosol (Tc99m sulfur colloid).
• Assessed whole-lung clearance over 90 minutes, with periodic vaping (60 puffs total) over the first 60 minutes.
• Utilized a fourth-generation box mod EC with unflavored e-liquid (3mg/mL nicotine).

Main Results:

• Peripheral lung clearance was significantly enhanced during EC challenge compared to baseline (24% ±6 vs. 12% ±6, p<0.05).
• This acute enhancement contrasts with studies showing nicotine-induced slowing of ciliary beat at higher concentrations.

Conclusions:

• Acute e-cigarette challenge appears to enhance *in vivo* MCC in young adults.
• Findings suggest a short-lived increase in bronchial airway surface fluid and mucin secretion.
• Further research is needed to understand the long-term implications of EC use on respiratory health.