Qualification and application of a modified electrostatic precipitation system for the analysis of metals in ENDS aerosol

In recent years, Electronic Nicotine Delivery Systems (ENDS) have gained popularity as an alternative to combustible cigarettes (CC). However, their increased use raises concerns regarding exposure to harmful and potentially harmful constituents (HPHCs), especially metals. While several methods have been published for collecting metals from ENDS aerosol, they are often hindered by background interference and inefficient aerosol collection. To address these challenges, a new aerosol collection method was developed and validated utilizing a modified electrostatic precipitation (EP) system connected to a Cerulean SM-450e puffing machine. Analysis of collected aerosol using an Agilent 7800 single quadrupole inductively coupled plasma mass spectrometer (ICP-MS) showed the new approach consistently provided a low background for chromium (Cr), nickel (Ni), copper (Cu), cadmium (Cd), and lead (Pb) in aerosol blanks, ensuring low method limits of detection (LOD). The unique design of the EP system effectively precipitated uncharged aerosol particles enabling collection of approximately 3.5 g of aerosol that minimized the average number of collections to two, required for complete sampling of ENDS products in this study. This method was used to collect aerosol samples from commercially purchased ENDS including pods and illicit disposables, many of which were found to contain quantifiable amounts of Cr (<10.1–1046.44 ng/g), Ni (<6.13–7659.7 ng/g), Cu (<7.53–25171.1 ng/g), Cd (<5.11–75.8 ng/g) and Pb (<5.18–1536.1 ng/g). This work shows the utility and advantages of electrostatic precipitation as a well-suited collection method for the analysis of low-level metals in ENDS aerosol.