Assessing Human Exposure to Hazardous Air Pollutants in the Home and Workplaces
The main objective of this proposed research is to reduce uncertainties in predicting exposure levels to volative hazardous air pollutants (HAPs). To meet this objective, we measured personal exposure, outdoor, indoor, and workplace concentrations as well as collected time activity data and the air exchange rate of their home for 55 study participants, of which 34 participated in two seasons. To further understand the origins of indoor concentrations, the contribution of secondary source areas such as basements, attached garages, and common apartment hallways were estimated for each home. The mean percent of the total air flow within the occupied zone of the residence from the basement was 26% (SD=34%) in the summer and 47% (SD=26%) in the winter while the mean percent from apartment hallways was 22% (SD=44%). Residences with garages attached to the basement had higher air flow rates to the adjacent zone (means from 50 to 887 m3/hr). Personal exposures will be compared to modeled exposures. Measurement of the workplace concentrations will improve the ability to capture personal exposure for our study participants.