A review of aerosol exposure systems relative to the analysis of cytotoxicity: a CORESTA In vitro Toxicity Testing Sub-Group perspective
Aerosol exposure systems offer researchers a variety of ways to customise the exposure set-up, modify experimental parameters and provide a novel and versatile platform for in vitro aerosol research. These systems produce an aerosol that more closely mimics the human smoking condition with associated aerosol interactions, an advantage over the potential limitation of using aerosol fractions alone. Exposure systems typically consist of two functional parts: the smoking machine / aerosol generator, and the exposure module/multiwell plate housing the cell system. The possible combinations of exposure systems, modules and plate formats give rise to an in vitro aerosol research environment that is complex and diverse, resulting in unique combinations of variables that few laboratories share. Ultimately, this causes challenges in comparing data between set-ups using similar systems and an inability to compare data across some platforms, making tobacco aerosol research particularly difficult to contextualise across laboratories.
Over recent meetings, the CORESTA In vitro Toxicity Testing Sub-Group has discussed the developing field of aerosol exposure research. Given the diversity of techniques, exposure parameters and biological end-points being deployed, it was considered a high priority to establish a strategy to assess these systems and the responses obtained. Twelve global companies with expertise in in vitro aerosol research met to discuss this topic and identify potential areas of alignment. A detailed and comprehensive survey was conducted on over 40 parameters ranging from aerosol generation, dilution, biological methodology, data analysis and dosimetry approaches, across eight independent laboratories.
Survey results demonstrate the diversity and provide awareness of the exposure systems, parameters, methodological nuances, and data analysis. Results identify potential commonalities and important areas of consideration, which may be of substantial benefit to current smoke/aerosol researchers, scientists from intersecting fields of research, and new scientists and laboratories entering into this area of research.