Development and Validation of a Simple Bioaerosol Collection Filter System Using a Conventional Vacuum Cleaner for Sampling

Abstract

Although numerous bioaerosol samplers for counting and identifying airborne microorganisms are available, the considerably high purchase and maintenance costs for the sampler often prevent broad monitoring campaigns for occupational or environmental surveillance of bioaerosols. We present here a newly developed simple adapter and filter system (TOP filter system) designed to collect bioaerosol particles from a defined air volume using conventional vacuum cleaners as air pumps. We characterized the physical properties of the system using air flow measurements and validated the biological performance. The culture-based detection capacities for airborne fungal species were compared to a standard impaction sampler (MAS-100 NT) under controlled conditions in a bioaerosol chamber (using Trichoderma spores as the test organism) as well as in the field. In the chamber, an overall equivalent detection capacity between all tested filters was recorded, although a significant underrepresentation of the TOP filter system for Trichoderma spores were seen in comparison to the MAS-100 NT. In a comparative field study (n = 345), the system showed similar biological sampling efficiencies compared to the MAS-100 NT impactor, only the diversity of identified fungal communities was slightly lower on the filters. Thus, the system is suitable for large-scale environmental sampling operations where many samples have to be taken in parallel at a given time at distant locations. This system would allow endeavors such as antibiotics resistance monitoring or hygiene surveys in agricultural or occupational settings.

Fungal Spore Richness and Abundance of Allergenic Taxa: Comparing a Portable Impactor and Passive Trap Indoors and Outdoors in an Urban Setting

“…Alternatively, others have similarly used a portable impactor with Petri dishes containing Vaseline [ 19 , 44 ], and filter cassettes with sampling pumps have also been used indoors [ 13 , 15 ]. Of note, a low-cost filter-based sampler operated with a conventional vacuum cleaner has been devised that may be used as an alternative to portable impactors with simple calibration [ 49 ]. The congruence between active devices in the estimation of fungal spore richness still requires investigation.…”

Biosensor detection of airborne respiratory viruses such as SARS-CoV-2

“…Membrane filters, also potentially including microfluidic platforms, are often used for bioaerosol collection in highly contaminated environments[ 20 , 24 , 25 ]. The particles can be directly examined from the filter using an optical microscope or can be cultured by placing the filter on a culture medium.…”

Metagenomics: An Effective Approach for Exploring Microbial Diversity and Functions

“…However, metagenomic studies of air samples face some challenges regarding microbial density, standardized methodologies, and bioinformatics tools [208]. Fortunately, the advent of new technologies for sample collections (i.e., the TOP filter system), DNA sequencing (i.e., Illumina, PacBio, and Oxford Nanopore Technologies platforms), and analysis pipelines (i.e., MEGAN and QIIME2) have allowed for the application of air metagenomics to explore metabolic pathways, bioremediation methods, and biogeochemical cycles [20,209]. Although the low biomass feature of the air environment has resulted in a lower number of microbes than in soil and water media, metagenomic research has revealed differing abundances of microbial communities [210].…”