AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Analysis of Nanoparticle Toxicity at the Air-Liquid Interface of Lung Cells
TREVOR TILLY, Ryan Ward, Alyssa Morea, Sarah Robinson, Arantzazu Eiguren Fernandez, Tara Sabo-Attwood, John Lednicky, Chang Yu Wu, University of Florida
Abstract Number: 643 Working Group: From Aerosol Dosimetry and Toxicology to Health
Abstract A bioinspired lung cell exposure system for toxicity analyses of nanoparticles, Dosimetric Aerosol in Vitro Inhalation Device (DAVID), was shown to have enhanced particle deposition efficiency through a physiologically relevant mechanism known as condensational particle growth. Condensational particle growth increases the size of aerosolized nanoparticles through the condensation of water vapor onto their surface, which amplifies particles as small as 10 nm in diameter to uniform micron-sized droplets, and this results in a gain inertia of particles in motion. Epithelial lung cells were cultured and exposed at the air-liquid interface (ALI) to CeO2 and CuO aerosols generated by a Collison nebulizer and an acoustic powder disperser. Use thereof resulted in distinct particle size distributions and a ten-fold difference in exposed aerosol mass concentration. CeO2 and CuO aerosols generated by the nebulizer resulted in high number concentrations (>106 #/cm3) with mean diameters similar to their primary particle sizes of 33.3±1.18 nm and 50.9±7.10 nm, respectively. The CeO2 and CuO aerosols generated by the acoustic disperser had a lower number concentration, but greater mass concentration than the nebulizer exposures, which resulted from their larger aerodynamic diameters of 3.06±0.45 μm and 2.25±0.07 μm, respectively. ALI cellular exposure to the CeO2 aerosol did not result in significant toxicity at a nebulizer dose level of 12.5 μg/cm2 or at the acoustic dose level of 109 μg/cm2. In contrast, exposing cells cultured at the ALI to CuO aerosols resulted in a dose dependent cellular membrane toxicity at all exposure concentrations (4.1 to 65 μg/cm2). Furthermore, submerged cells exposed to CeO2 nanoparticles did not reduce cell viability, but exposure to 20 μg/mL of CuO resulted in greater than 50% decrease in mitochondrial activity. The findings indicate a potential difference in the toxicity mechanisms for cells exposed to particles as an aerosol and under submerged culture conditions.