Filtration Efficiency of Air Conditioner Filters and Face Masks to Limit Exposure to Aerosolized Algal Toxins

ABSTRACT Harmful algal blooms (HABs) can generate toxins that be aerosolized and negatively impact human health through inhalation. HABs are often found in waterways near residences, therefore, HAB potentially affect both indoor outdoor air quality. Given predicted to increase worldwide, effective mitigation strategies needed prevent the inhalation of toxins. In this work, we characterized particle filtration efficiency using sizing instruments as well mass concentration different congeners microcystin (MC) penetrate commercially available face masks conditioner (AC) filters. Particles were generated from cultures toxin-producing cyanobacteria Microcystis aeruginosa. Hydrophobic including MC-LF MC-LW enriched aerosols compared water, with MC-LR being most abundant, which has implications for toxicity inhalable particles HAB-contaminated waters. Particle transmission efficiencies toxin scaled manufacturer-provided filter performance ratings. Up 80% small, microcystin-containing transmitted AC filters low contrast, high ratings efficiently removed toxin-containing below limits quantification. Our findings suggest suitable avoid exposure This work also relevance reducing airborne other toxins, non-HAB pathogens, viruses, SARS-CoV-2, virus responsible COVID-19 pandemic.