AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
In Vitro Exposures to Isoprene-Derived Secondary Organic Aerosol: Assessing the Effects of Cytotoxicity and Inflammation on BEAS-2B using Resuspension and Direct Deposition Approaches
MAIKO ARASHIRO, Ying-Hsuan Lin, Kenneth Sexton, Ilona Jaspers, Rebecca Fry, Avram Gold, Jason Surratt, University of North Carolina at Chapel Hill
Abstract Number: 117 Working Group: Linking Aerosols with Public Health in a Changing World
Abstract Although gaseous isoprene has been classified by the International Agency for Research on Cancer (IARC) as “possibly carcinogenic to humans (Group 2B), little is known about the health effects of isoprene-derived secondary organic aerosol (SOA) due to being recently recognized as an SOA precursor. Recent work from our laboratory has shown that anthropogenic pollutants, such as nitrogen oxides (NO$_x) and sulfur dioxide (SO$_2), enhance isoprene oxidation leading to SOA formation. Current understanding of the effects of gaseous products from oxidation of isoprene and its analog, 1,3- butadiene, on cytotoxicity and inflammation suggests that there may be similar effects associated with inhalation of isoprene-derived SOA. This study focuses on investigating the health effects associated with the inhalation of isoprene-derived SOA formed in the presence of acidified sulfate aerosol and initially high nitric oxide (NO) conditions. The objective of this study is to examine toxicity of these isoprene-derived SOA through a resupension exposure method and a direct deposition exposure method.
Outdoor smog chamber experiments were conducted to systematically generate SOA from the photochemical oxidation of isoprene. Human bronchial epithelial cells (BEAS-2B) were exposed to the chemical mixture generated in the chamber in two ways: (1) resuspension of particles collected onto filters; and (2) direct deposition of particles directly from air onto the air-liquid interface of cells using an instrument called the electrostatic aerosol in vitro exposure system (EAVES). Cytotoxicity and inflammatory biomarkers (IL-8 and COX-2) measured from the exposed cells will highlight benefits and limitations of each exposure method. Biological measurements together with complementary chemical measurements will identify potential toxicity associated with inhalation of isoprene-derived SOA.