ARB Research Seminar
This page updated December 12, 2013
Persistent Immune Effects of Wildfire PM Exposure During Childhood Development
Lisa Miller, Ph.D., University of California, Davis
January 07, 2014
Cal EPA Headquarters, 1001 "I" Street, Sacramento, CA
During July 2008 a series of wildfires ignited in Northern California, leading to high PM2.5 levels in the Sacramento Valley that lasted for about two weeks. The California National Primate Center, at UC Davis, has a large population of rhesus macaque monkeys that live in outdoor field cages, where they were exposed to these elevated air pollution levels. The fires occurred near the end of the season when the monkey's babies are typically born, and thus there were a significant number of animals in the colony that were between one and three months of age at the time of the fires.
Infancy may be associated with increased vulnerability to high levels of air pollution exposure because of the rapid lung and immune system development that occur during the early months of life. Several studies suggest that short-term exposure to wildfire emissions (over a few days) can worsen symptoms of asthma and other lung diseases, but no studies have investigated whether there are long-term health consequences to such exposures. To address gaps in our understanding of the biologic effects of air pollutant exposure during early life, the investigators compared the levels of immune system activation in smoke exposed animals, and in a group of animals born during the same months the following year during which there were no wildfires. Both groups of animals also completed a series of lung function tests. All animals were studied when they were three years of age (young adulthood). No animals were harmed in any way during the study.
The results showed lower levels of markers of immune system activation in smoke exposed animals compared to control animals, suggesting that these animals are more susceptible to infectious diseases. Animals that had the most impaired response to bacterial challenge tended to also have reductions in several measures of lung function, particularly female animals. These results suggest that infancy is a period during which high PM2.5 exposures may adversely influence development of the branch of the immune system that combats infectious disease, and also adversely affects the development of lung function, leading to changes that persist into adulthood.
Lisa Miller, Ph.D., is an Associate Professor at the Department of Anatomy, Physiology, and Cell Biology at the School of Veterinary Medicine, University of California, Davis. After joining the school in 1997, Dr. Miller was appointed Associate Professor in 2008. In addition to her research program in pulmonary immunology, Dr. Miller teaches an immunology course for graduate students and anatomy for first year veterinary students. Dr. Miller completed her doctorate in comparative pathology from UC Davis and completed a postdoctoral fellowship at Stanford University.