Indoor, outdoor, and personal exposure monitoring of particulate air pollution: the Baltimore elderly epidemiology-exposure pilot study

A 17-day pilot study investigating potential PM exposures of an elderly pop ulation was conducted near Baltimore, Maryland. Collection of residential i ndoor, residential outdoor, and ambient monitoring data associated with the subjects living at a common retirement facility was integrated with result s from a paired epidemiological pilot study. This integration was used to i nvestigate the potential pathophysiological health effects resulting from d aily changes in estimated PM exposures with results reported elsewhere. Obj ectives of the exposure study were to determine the feasibility of performi ng PM exposure assessment upon an elderly population and establishing relat ionships between the various exposure measures including personal monitorin g. PM2.5, was determined to be the dominant outdoor size fraction (0.83 PM2 .5/PM10 mass ratio by dichot monitoring). Individual 24-h PM1.5 personal ex posures ranged from 12 to 58 mu g m(-3). Comparison of data from matched sa mpling dates resulted in mean daily PM1.5 personal, PM2.5 outdoor, and PM1. 5 indoor concentrations of 34, 17, and 17 mu g m(-3), respectively. Activit y patterns of the study population indicated a generally sedentary populati on spending a mean of 96% of each day indoors. Future studies would benefit from the use of a consistent sampling methodology across a larger number o f PM measurement sites relevant to the elderly subjects, as well as a large r personal PM exposure study population to more successfully collect data n eeded in matched epidemiological-exposure studies. Published by Elsevier Sc ience Ltd.