| Title: | "Impacts of a large boreal wildfire on ground level atmospheric concentrations of PAHs, VOCs and ozone" |
| Author(s): | Wentworth GR; Aklilu YA; Landis MS; Hsu YM; |
| Address: | "Environmental Monitoring and Science Division, Alberta Environment and Parks, 10th Floor 9888 Jasper Ave. NW, T5J 5C6, Edmonton, AB, Canada. US Environmental Protection Agency, Office of Research and Development, Research Triangle Park, 27709, NC, USA. Wood Buffalo Environmental Association, 100-330 Thickwood Blvd., T9K 1Y1, Fort McMurray, AB, Canada" |
| DOI: | 10.1016/j.atmosenv.2018.01.013 |
| ISSN/ISBN: | 1352-2310 (Print) 1352-2310 (Linking) |
| Abstract: | "During May 2016 a very large boreal wildfire burned throughout the Athabasca Oil Sands Region (AOSR) in central Canada, and in close proximity to an extensive air quality monitoring network. This study examines speciated 24-h integrated polycyclic aromatic hydrocarbon (PAH) and volatile organic compound (VOC) measurements collected every sixth day at four and seven sites, respectively, from May to August 2016. The sum of PAHs (SigmaPAH) was on average 17 times higher in fire-influenced samples (852 ng m(-3), n = 8), relative to non-fire influenced samples (50 ng m(-3), n = 64). Diagnostic PAH ratios in fire-influenced samples were indicative of a biomass burning source, whereas ratios in June to August samples showed additional influence from petrogenic and fossil fuel combustion. The average increase in the sum of VOCs (SigmaVOC) was minor by comparison: 63 ppbv for fire-influenced samples (n = 16) versus 46 ppbv for non-fire samples (n = 90). The samples collected on August 16th and 22nd had large SigmaVOC concentrations at all sites (average of 123 ppbv) that were unrelated to wildfire emissions, and composed primarily of acetaldehyde and methanol suggesting a photochemically aged air mass. Normalized excess enhancement ratios (ERs) were calculated for 20 VOCs and 23 PAHs for three fire influenced samples, and the former were generally consistent with previous observations. To our knowledge, this is the first study to report ER measurements for a number of VOCs and PAHs in fresh North American boreal wildfire plumes. During May the aged wildfire plume intercepted the cities of Edmonton ( approximately 380 km south) or Lethbridge ( approximately 790 km south) on four separate occasions. No enhancement in ground-level ozone (O(3)) was observed in these aged plumes despite an assumed increase in O(3) precursors. In the AOSR, the only daily-averaged VOCs which approached or exceeded the hourly Alberta Ambient Air Quality Objectives (AAAQOs) were benzene (during the fire) and acetaldehyde (on August 16th and 22nd). Implications for local and regional air quality as well as suggestions for supplemental air monitoring during future boreal fires, are also discussed" |
| Keywords: | Air quality Fort McMurray Ozone Pah Voc Wildfire; |
| Notes: | "PubMed-not-MEDLINEWentworth, Gregory R Aklilu, Yayne-Abeba Landis, Matthew S Hsu, Yu-Mei eng EPA999999/Intramural EPA/ England 2018/04/24 Atmos Environ (1994). 2018 Apr; 178:19-30. doi: 10.1016/j.atmosenv.2018.01.013" |
