Air quality and exposure monitoring of sulfur dioxide in the community of Fort McKay: A baseline assessment

Oil sands operations in northern Alberta yield sulfur dioxide (SO2) as a by-product. The objective of this study was to measure baseline levels of SO2 in indoor and outdoor air in Fort McKay, Alberta, in order to assess whether proximity to increased oil sands activities affects air quality in the community.;In fall 1999, 30 households were randomly chosen for indoor and outdoor passive sampling of SO2. Four-day time weighted levels of SO 2 and air exchange rates were measured.;Indoor levels of SO2 (n = 30; 100% less than level of detection, 1.3 mug/m3) were minimal and lower than outdoor levels (n = 28; 64% above level of detection; mean: 1.6 mug/m3; range: 1.3 to 3.6 mug/m3). Thus, oil sands activities during the monitoring period did not increase levels of indoor/outdoor SO2 to levels intended for human health protection. Air exchange rates (mean: 0.38 air changes per hour; range: <0.01 to 0.73 air changes per hour) were consistent with typical air exchange rates in North American homes.