AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
A New Instrument for Direct Cellular Exposure to Ambient Aerosols
ARANTZAZU EIGUREN FERNANDEZ, Ning Li, Steven Spielman, Susanne Hering, Aerosol Dynamics Inc.
Abstract Number: 448 Working Group: Instrumentation and Methods
Abstract A new instrument has been developed for direct cell exposure to ambient aerosols. Vapors and particles are delivered directly into the cell culture providing a realistic exposure scenario for in-vitro toxicity studies. Particles and vapor-phase components are collected into the liquid without disturbing the cells, reducing possible cellular stress produced during collection.
This new system is based on water condensational growth of ambient particles. It samples at 8 lpm. To minimize surface disruption and maximize collection, aerosols are delivered through 32 impaction nozzles, each carrying 0.25 lpm. The exposure chamber is kept at 37$^oC for optimum cell survival. As cell cultures require a 5% CO2 environment, a 0.4 lpm CO2 flow is added at the inlet and mixed with the incoming flow.
By challenging the system with monodisperse particles, collection efficiencies >95% were demonstrated for particles between 10nm and 2.5µm.
Preliminary studies evaluating cell viability after exposure to aerosols were conducted using mouse macrophage cell line RAW 264.7 and human bronchial epithelial cell line BEAS-2B. Both lines have been widely used as in-vitro models to study the adverse effects of various air pollutants. Two exposure conditions were evaluated, high and low particle concentrations. For low concentrations (~3x103#/cc) no difference between control and exposed cells were observed after 1 hr, 3 hr and 6 hr exposures. For high concentrations, cells were exposed to emissions from burning incense with particle concentrations over 5x105#/cc. After 5, 20, and 120 min exposure cells were viable; however, after overnight incubation with the exposed medium, cell viability was determined to be 80%, 20% and 0%, respectively. These results showed a dose-response effect to extremely high exposure conditions.
These preliminary results suggest that the new system may provide a new tool for direct cellular exposure to ambient aerosols, allowing a realistic study of the toxicity of aerosols.