Effect of Puffing Behavior on Particle Size Distributions and Respiratory Depositions From Pod-Style Electronic Cigarette, or Vaping, Products.

Introduction:
This article presents a study on the effect of puffing behavior on particle size distributions and respiratory depositions from pod-style electronic cigarette or vaping products (EVPs). The study investigates the influence of up to six puff profiles on particle size distribution (PSD) using a popular pod-style EVP (JUUL® brand) and a cascade impactor. The research aims to estimate regional respiratory deposit ion, exhaled fraction of EVP aerosols, and potential secondhand exposure hazards in indoor occupational settings.

Key Points:

* The study used a popular pod-style EVP (JUUL® brand) and a cascade impactor to investigate the influence of up to six puff profiles on particle size distribution (PSD).
* The researchers evaluated both pre-filled disposable and re-fillable pod-style EVPs.
* The study found that MMaDs did not differ among puff profiles, except for 55- and 75-ml volumes at 7.5W.
* For the reference e-liquid, MMaDs ranged from 1.02 to 1.23 µm, and dosimetry calculations predicted that particles would deposit in the head region (36-41%), trachea-bronchial (TB) region (19-21%), and pulmonary region (40-43%).
* For commercial JUUL® e-liquids, MMaDs ranged from 0.92 to 1.67 µm, and modeling predicted that more particles would deposit in the head region (35-52%) and in the pulmonary region (30-42%).
* The study estimated that 30-40% of the particles aerosolized by a pod-style EVP would deposit in the pulmonary region, and 50-70% of the inhaled EVP aerosol could be exhaled, presenting an inhalational hazard to bystanders in indoor occupational settings.
* Research on the influence of other modifiable factors on PSD and exposure potential is needed.

Main Message:
This study highlights the significance of puffing behavior in modulating the particle size distribution and respiratory depositions of pod-style EVPs. The findings emphasize the potential health risks associated with secondhand exposure to EVP aerosols, particularly in indoor occupational settings. as regulations and guidelines are developed for EVPs, understanding the impact of puffing behavior and other modifiable factors on particle size distribution and respiratory depositions is crucial. This information can inform policymakers in implementing evidence-based measures to minimize potential health hazards associated with EVP use.

Ranpara a, Stefaniak aB, Fernandez E, LeBouf RF. Effect of Puffing Behavior on Particle Size Distributions and Respiratory Depositions From Pod-Style Electronic Cigarette, or Vaping, Products. Frontiers in public health. 2021;9:750402. doi:10.3389/fpubh.2021.750402