ARB Research Seminar

Dr. Colin Solomon, Department of Medicine, University of California, San Francisco

June 17, 2004
Cal EPA Headquarters, 1001 "I" Street, Sacramento, CA

Presentation
Research Project

• John Balmes, M.D., Mechanisms of Particulate Toxicity: An Overview
• Karron Power, M.D., Heart Rate Variability Following Controlled Exposure to Particles and Ozone in Asthmatic Individuals
• Michael T. Kleinman, Ph.D., Inflammatory and Cardiovascular Responses to Inhaled Fine Particles
• Kent Pinkerton, Ph.D., Effects on the Respiratory System of Sensitive Animals and Asthmatic Humans

Overview

This project investigated the effect of inhaled particles on airway inflammation in individuals with asthma. One experiment involved separate single exposures to each of filtered air (FA), carbon and ammonium nitrate particles (P), and P with ozone (PO). The second experiment involved separate single exposures to FA, P, and three serial-day exposures to P (P3). In PO, compared to FA and P, there were increases in airway inflammatory cells, proteins, and gene expression, and decreases in spirometric pulmonary function (SPF). Within the P3 condition there were decreases in SPF. The results indicate that exposure to the particles can lead to decreases in SPF function, but does not lead to any physiologically significant changes in airway cell distribution, protein, or gene expression. However, combined exposure to particles and ozone, in addition to decreases in SPF, does lead to increases in inflammatory cells, and protein and gene expression. These differential changes appear to be due primarily to the ozone component of the exposure environment.

Speaker Biography

Colin Solomon received his Ph.D. in physiology from the University of Queensland, Australia. He is an assistant professor in the Department of Medicine at the University of California at San Francisco. Dr. Solomon investigates the mechanisms of toxin-induced (gas and particle) airway inflammation in humans using controlled exposure experiments.