Sources, spatial-distributions and fluxes of PAH-contaminated dusts in the Athabasca oil sands region

[Display omitted] •PAH sources and summertime deposition in Canada’s oil sands region were quantified.•Deposition of PAHs to the oil sands region was > 100 kg on > 14,000 tonnes of dust.•PAH deposition was greatest around the First Nations community of Fort MacKay.•The major sources of PAH-contaminated dust included both fine tailings and petcoke.•PAH concentrations in the region were double those in or around two Canadian cities. Atmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) has increased in northern Alberta, Canada, due to industrial development in the Athabasca oil sands region (AOSR). However, the sources, summertime deposition fluxes and associated spatial patterns are poorly characterized, and the magnitude of contamination has not been directly contrasted with comparable measurements around large Canadian cities. PAHs were measured in Sphagnum moss collected from 30 bogs in the AOSR and compared with reference moss collected from various remote, rural and near-urban sites in Alberta and Ontario. At all 39 locations, strong correlations between depositional fluxes of PAHs and accumulation rates of ash (n = 117, r = 0.877, p