Abstract View
Particle and Toxin Filtration Efficiencies of Commercially Available Face Masks and Air Conditioning Filters to Reduce Exposure to and Health Impacts of Aerosolized Algal Toxins
CASSANDRA GASTON, Haley Royer, Raymond Leibensperger III, Michael Sheridan, Jiaming Hu, Kaycie Lanpher, Daniela Maizel, Helena Solo-Gabriele, Grace Zhai, Larry Brand, Alberto Caban-Martinez, Kimberly Popendorf, University of Miami
Abstract Number: 46
Working Group: Health-Related Aerosols
Abstract
Harmful algal blooms (HABs) can generate toxins that can be aerosolized and negatively impact human health through inhalation. HABs are often found in waterways near residences, therefore, aerosolized HAB toxins can potentially affect both indoor and outdoor air quality. Given that HABs are predicted to increase worldwide, knowledge of the health impacts associated with the inhalation of aerosolized HAB toxins are needed in addition to effective mitigation strategies to prevent airborne exposure. In this work, we characterized both the particle filtration efficiency using particle sizing instruments as well as the mass concentration of different congeners of aerosolized microcystin (MC) toxins that penetrate through commercially available face masks and air conditioner (AC) filters. Particles were generated from cultures of the toxin-producing cyanobacteria Microcystis aeruginosa. Hydrophobic congeners of microcystin including MC-LF and MC-LW were enriched in aerosols compared to water, with MC-LR being the most abundant form, which has implications for the toxicity of inhalable particles generated from HAB-contaminated waters. Particle transmission efficiencies and toxin filtration efficiencies scaled with the manufacturer-provided filter performance ratings. Up to 80% of small, microcystin-containing aerosols were transmitted through AC filters with low filter performance ratings. In contrast, both face masks as well as AC filters with high filter performance ratings efficiently removed toxin-containing particles to below limits of quantification. Our findings suggest that face masks and commercially available AC filters with high filtration efficiency ratings are suitable mitigation strategies to avoid indoor and outdoor air exposure to aerosolized HAB toxins. This work also has relevance for reducing airborne exposure to other HAB toxins, non-HAB toxins, pathogens, and viruses, including SARS-CoV-2, the virus responsible for the COVID-19 pandemic.