A Brief History of Bioaerosol Sampling: From Early Innovations to Future Prospects

GEDIMINAS MAINELIS, Rutgers, The State University of New Jersey

     Abstract Number: 399
     Working Group: History of Aerosol Science

Abstract
Effective bioaerosol sampling techniques are fundamental to understanding airborne microbial exposure and its implications for health and environmental science. While bioaerosol researchers typically do not give much thought to how their sampling tools have evolved, the history of bioaerosol sampling technologies offers a window into technological development and the state of science in the past, while also offering guidance for future developments. The earliest documented observations of bioaerosols date back to Darwin’s 1833 discovery of airborne mold spores, demonstrating the natural transport of microbial particles through the air. Louis Pasteur’s 1860 experiment, designed to disprove spontaneous generation, inadvertently demonstrated passive bioaerosol sampling principles, as bacteria settled under gravity into the nutrient broth. Thus, early bioaerosol sampling techniques relied on passive collection methods, such as sedimentation plates, which were limited by environmental variability and low collection efficiency. By the late 19th and early-mid 20th centuries, the development of active sampling methods, such as impingers (e.g., sampling flask and bacterial Aeroscope) and impactors (e.g., Andersen impactor), revolutionized bioaerosol collection by incorporating controlled airflow for enhanced particle capture on solid or liquid media. The development of filter-based samplers further enhanced collection precision, allowing for prolonged sampling durations and concentration-based analysis. The introduction of the electrostatic sampling concept in the 1940s has provided new avenues for improving collection efficiency and preservation. A renewed interest in passive sampling technologies offers the possibility of inexpensive tools that could be widely distributed over wide spatial areas. However, many challenges still remain, including long-term sampling, personal exposure assessment, compatibility of sampling methods, improving detection limits, standardization of sample analysis protocols, real-time detection technologies, and integration with molecular analysis. This presentation will highlight the key milestones in bioaerosol sampling technology, addressing current challenges and exploring emerging innovations that may shape the future of the field.