American Association for Aerosol Research - Abstract Submission

AAAR 39th Annual Conference
October 18 - October 22, 2021

Virtual Conference

Abstract View


2020 California Wildfire Smoke in New Mexico: Characterization and Toxicological Studies Reveal Signs of Neurological Aging and Inflammation

David Scieszka, Russell Hunter, Jessica Begay, Marsha Bitsui, Yan Lin, Joseph Galewsky, Masako Morishita, Zachary Klaver, James Wagner, Jack Harkema, Guy Herbert, Selita Lucas, Charlotte McVeigh, Alicia Bolt, Barry Bleske, Andrew Ottens, Haiwei Gu, Shahani Noor, MATTHEW CAMPEN, University of New Mexico

     Abstract Number: 347
     Working Group: Wildfire Aerosols

Abstract
Wildfire smoke originating from California routinely spread across the western states throughout the summer and fall of 2020. Using a mobile laboratory with a particle concentrating system located on the Laguna Pueblo, approximately 1h west of Albuquerque, we conducted a 20-day, 4h/d whole body exposure in C57BL/6 male mice and examined pulmonary and systemic, especially neurological inflammatory consequences. The mobile laboratory-based concentration of PM2.5 led to exposure levels averaging 104 µg/m3, with high levels of 209 and 191 µg/m3 seen on the first 2 days of exposure, during the peak of wildfire PM2.5 transport to this region. We also measured the overall content of levoglucosan, a specific marker for wood smoke, in pooled PM filter samples, which revealed that the first 3 days of exposure had a high contribution of wood burning in the PM2.5. Days 13-16 of the exposure also contained modestly elevated levoglucosan. Inflammation was evident in the lung of PM-exposed mice, with elevated numbers of macrophages in bronchoalveolar lavage and several cytokines (MIP1, MIP2, IP10 increased relative to filtered air control mice. Wildfire PM exposure also led to signs of inflammation in the bone marrow (MIP2, IP10). Flow cytometry conduct in brains reveal substantial increases in numbers of activated microglia, infiltration of peripheral leukocytes, and increased expression of adhesion molecules on cerebrovascular endothelial cells. Metabolomics of the cerebellum revealed reduced NAD+, succinate, and taurine in PM-exposed mice, consistent with metabolic shifts associated with aging. These outcomes, from PM traveling across the continent, suggest broad-scale public health neurological impacts may arise from wildfires.