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

The current fourth generation (“pod-style”) electronic cigarette, or vaping, products (EVPs) heat a liquid (“e-liquid”) contained in a reservoir (“pod”) using a battery-powered coil to deliver aerosol into the lungs. A portion of inhaled EVP aerosol is estimated as exhaled, which can present a potential secondhand exposure risk to bystanders. The effects of modifiable factors using either a prefilled disposable or refillable pod-style EVPs on aerosol particle size distribution (PSD) and its respiratory deposition are poorly understood. In this study, the influence of up to six puff profiles (55-, 65-, and 75-ml puff volumes per 6.5 and 7.5 W EVP power settings) on PSD was evaluated using a popular pod-style EVP (JUUL® brand) and a cascade impactor. JUUL® brand EVPs were used to aerosolize the manufacturers' e-liquids in their disposable pods and laboratory prepared “reference e-liquid” (without flavorings or nicotine) in refillable pods. The modeled dosimetry and calculated aerosol mass median aerodynamic diameters (MMADs) were used to estimate regional respiratory deposition. From these results, exhaled fraction of EVP aerosols was calculated as a surrogate of the secondhand exposure potential. Overall, MMADs did not differ among puff profiles, except for 55- and 75-ml volumes at 7.5 W (p < 0.05). 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%), in the trachea-bronchial (TB) region (19–21%), and in the 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%). Overall, 30–40% of the particles aerosolized by a pod-style EVP were estimated to deposit in the pulmonary region and 50–70% of the inhaled EVP aerosols could be exhaled; the latter could present an inhalational hazard to bystanders in indoor occupational settings. More research is needed to understand the influence of other modifiable factors on PSD and exposure potential.

A practical approach to assess the hazardous exposure potential of investigational drugs

Purpose A method to evaluate the hazardous exposure potential of investigational drugs was developed in order to comply with hazardous drug handling standards. Summary New nationwide standards require health-system pharmacies to recognize potential occupational risks and protect employees from any hazardous exposure. United States Pharmacopeia general chapter 800 (USP<800>) provides recommendations on handling precautions for commercial hazardous drugs. Recommendations for investigational drugs are less clear, with USP<800> suggesting more widespread protections when information is deemed insufficient to assess the risk. The investigational drug services pharmacy at a freestanding pediatric hospital developed a method to evaluate the hazardous potential of investigational drugs in order to determine the likelihood that a drug held an occupational handling risk. The goal of the project was to ensure compliance with hazardous drug handling standards and provide adequate employee protection while minimizing the financial burden on the health-system pharmacy. Conclusion Investigational drugs that meet any of 4 defined criteria should be subject to hazardous drug handling precautions until adequate safety data are available.