Wildfire Smoke Exposure During Infancy Results in Impaired Lung Function

Abstract

Rationale: Wildfires are predicted to increase in frequency as a result of climate change. The impact of acute wildfire smoke inhalation on development of chronic disease is unknown. Previously, we have reported lung function decrements in a cohort of adolescent rhesus macaque monkeys that were exposed as infants to the Northern California wildfires (Black, et. al. 2017). For this current study, we hypothesized that pulmonary changes due to early life wildfire smoke exposure would persist into adulthood and lead to transmission of maternal phenotype into offspring. Methods: Adult female rhesus monkeys were born and reared in an outdoor environment within three months prior to the Trinity and Humboldt County summer wildfires in 2008, which produced significant episodes of PM2.5 exposures within one mile of the primate colony. High resolution computerized tomography (CT) imaging of the thoracic cavity was conducted on adult animals only. CT scans were analyzed using Functional Respiratory Imaging to quantify structural changes and functional deficits. A second cohort born in the spring of 2009 served as a control group; biospecimen collection and imaging were conducted in subsequent years to normalize age. Results: CT scans from wildfire smoke-exposed adult monkeys showed significant reductions in lung volume, inspiratory capacity, and ventilation perfusion relative to controls. A significant increase in specific airway radius and blood vessel density was also detected in wildfire smoke-exposed adult monkeys. Conclusions: Our findings demonstrate that early life ambient wildfire smoke exposure results in pulmonary responses that persist into adulthood. Funding: California Air Resources Board and NIEHS T32 ES007059