Map of study area - Bay Area coal trains (IMAGE) University of California - Davis Caption A figure from the UC Davis coal train pollution study showing the study area with estimated PM2.5 concentrations associated with a 2.1 μg/m3 increase in the annual PM2.5 average. Credit UC Davis Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.