Optimizing a Test Bed System to Assess Human Respiratory Safety After Exposure to Chemical and Particle Aerosolization

Abstract

In the last decade, there has been a movement within environmental health and toxicology research to progressively phase out animal testing and implement more rigorous and validated cell culture models. This movement is checked against the rapidly evolving field of immunotoxicology and measurement of immune-mediated cellular responses. Both trends are driven by many variables, some of which are common in both (i.e., increased time constraints; social, financial, and regulatory pressures; and general need to develop modern test bed systems for safety-by-design product development). The need for non-animal alternative test methodology is especially important in the field of immunotoxicology, where increased emphasis has been placed on distinguishing dermal, respiratory, and gastrointestinal sensitization and/or irritation, defining key markers for hazard identification, and developing potential high-throughput screening processes. With these drivers in mind, this article summarizes the key components of developing a prototype test bed system to rapidly determine immunotoxicological responses following exposure to aerosolized materials. Inhalation exposure to aerosolized substances (e.g., chemicals and particles) is a common occurrence for individuals working in research laboratories, engaged in industrial processes, in consumer use of household products, and during the waste disposal process. We recommend research priorities with emphasis on developing continuous flow testing systems, inclusive of aerosolization, cell culture exposure, and immunological endpoint analyses.

Exploring the science, safety, and benefits of air care products: perspectives from the inaugural air care summit

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“In Litero” Screening: Retrospective Evaluation of Clinical Evidence to Establish a Reference List of Human Chemical Respiratory Sensitizers

“…When occupational asthma is suspected, specific inhalation challenge (SIC) is often difficult due to the presence of confounding materials in the environment and, more importantly, the reality of risk to the patient. In allergic asthma, the condition develops as a result of two phases: induction (sensitization), with initial exposure to the causative agent, and elicitation (allergic response) upon re-challenge (Sayes, 2018). Controlled workplace challenge tests with a measurement of serial peak expiratory flow or spirometry, specifically, forced expiratory volume in the first second (FEV 1 ), while in the workplace and away, can be helpful (Beckett, 1994).…”

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