[en] Highlights: • Pb isotopes measured in PM_2.5 and PM_10–2.5 from Fort McKay, Alberta in 2010–2011 • Eastern Asia sources contributed 47% of the Pb in the PM_2.5 in 2010–2011. • Pb isotopes measured in lichens around mining operations in 2008, 2011, and 2014 • 46% of the lichen Pb from regional, 32% from local, and 22% from global sources -- Abstract: Ambient air particulate matter (PM) was collected at the Wood Buffalo Environmental Association Bertha Ganter Fort McKay monitoring station in the Athabasca Oil Sand Region (AOSR) in Alberta, Canada from February 2010 to July 2011 as part of an air quality source assessment study. Daily 24-hour duration fine (PM_2.5) and coarse (PM_10–2.5) PM was collected using a sequential dichotomous sampler. 100 pairs of PM_2.5 and PM_10–2.5 were selected for lead (Pb) concentration and isotope analysis. Pb isotope and concentration results from 250 epiphytic lichen samples collected as far as 160 km from surface mining operations in 2008, 2011, and 2014 were analyzed to examine longer term spatial variations in Pb source contributions. A key finding was recognition of thorogenic ²⁰⁸Pb from eastern Asia in the springtime in the PM_2.5 in 2010 and 2011. ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁷Pb isotope ratios were used in a three-component mixing model to quantify local, regional, and global Pb sources in the PM and lichen data sets. 47 ± 3% of the Pb in the PM_2.5 at AMS-1 was attributed to sources from eastern Asia. Combined results from PM_10–2.5 and PM_2.5 indicate PM_2.5 Pb contributions from eastern Asia (34%) exceed local AOSR sources of PM_2.5 Pb (20%), western Canada sources of PM_2.5 Pb (19%), and PM_10–2.5 Pb from fugitive dust including oil sands (14%), tailings (10%), and haul roads (3%). The lichen analysis indicates regional sources contribute 46% of the Pb, local sources 32%, and global sources 22% over the 2008–2014 timeframe. Local sources dominate atmospheric Pb deposition to lichens at near field sites (0–30 km from mining operations) whereas regional Pb sources are prevalent at distal sites (30–160 km). The Pb isotope methodology successfully quantified trans-Pacific transport of Pb to the AOSR superimposed over the aerosol footprint of the world's largest concentration of bitumen mining and upgrading facilities.

[en] Highlights: • Ambient PM PAH source apportionment study conducted in Athabasca Oil Sands Region. • Receptor modeling elucidated and quantified significant contributing PM sources. • C1- and C2-alkyl PAHs and dibenzothiophenes utilized as tracer species. • One pyrogenic PM_2.5 source factor contributed 78% of the measured ΣPAH. • One organic aerosol PM_10–2.5 source factor contributed 86% of the measured ΣPAH. -- Abstract: A comprehensive filter-based particulate matter polycyclic aromatic hydrocarbon (PAH) source apportionment study was conducted at the Wood Buffalo Environmental Association Bertha Ganter-Fort McKay (BGFM) community monitoring station from 2014 to 2015 to quantify ambient concentrations and identify major sources. The BGFM station is located in close proximity to several surface oil sands production facilities and was previously found to be impacted by their air emissions. 24-hour integrated PM_2.5 and PM_10–2.5 samples were collected on a 1-in-3-day schedule yielding 108 complete organic/inorganic filter sets for source apportionment modeling. During the study period PM_2.5 averaged 8.6 ± 11.8 μg m⁻³ (mean ± standard deviation), and PM_10–2.5 averaged 8.5 ± 9.5 μg m⁻³. Wind regression analysis indicated that the oil sands production facilities were significant sources of PM_2.5 mass and black carbon (BC), and that wildland fires were a significant source of the highest PM_2.5 (>10 μg m⁻³) and BC events. A six-factor positive matrix factorization (PMF) model solution explained 95% of the measured PM_2.5 and 78% of the measured ΣPAH. Five sources significantly contributed to PM_2.5 including: Biomass Combustion (3.57 μg m⁻³; 40%); Fugitive Dust (1.86 μg m⁻³; 28%); Upgrader Stack Emissions (1.44 μg m⁻³; 21%); Petrogenic PAH (1.20 μg m⁻³; 18%); and Transported Aerosol (0.43 μg m⁻³ and 6%). However, the analysis indicated that only the pyrogenic PAH source factor significantly contributed (78%) to the measured ΣPAH. A five-factor PMF model dominated by fugitive dust sources explained 98% of PM_10–2.5 mass and 86% of the ΣPAH. The predominant sources of PM_10–2.5 mass were (i) Haul Road Dust (4.82 μg m⁻³; 53%), (ii) Mixed Fugitive Dust (2.89 μg m⁻³; 32%), (iii) Fugitive Oil Sand (0.88 μg m⁻³; 10%), Mobile Sources (0.23 μg m⁻³; 2%), and Organic Aerosol (0.06 μg m⁻³; 1%). Only the Organic Aerosol source significantly contributed (86%) to the measured ΣPAH.

[en] Highlights: • Horse River Fire had a major air quality impact on the city of Fort McMurray. • PM_2.5 enhancements at the community monitoring sites ranged from a factor of 19–54. • Significant enhancements of NMHC, NH₃, BC, DC, TRS, NOx, and H₂S were observed. • First observations of reduced sulfur compounds (TRS/H₂S) emissions from a wildfire • Fire PM_2.5 profiles were uniform across the network, can be used as a fingerprint. An unprecedented wildfire impacted the northern Alberta city of Fort McMurray in May 2016 causing a mandatory city wide evacuation and the loss of 2,400 homes and commercial structures. A two-hectare wildfire was discovered on May 1, grew to ~ 157,000 ha by May 5, and continued to burn an estimated ~ 590,000 ha by June 13. A comprehensive air monitoring network operated by the Wood Buffalo Environmental Association (WBEA) in and around Fort McMurray provided essential health-related real-time air quality data to firefighters during the emergency, and provided a rare opportunity to elucidate the impact of gaseous and particulate matter emissions on near-field communities and regional air pollution concentrations. The WBEA network recorded 188 fire-related exceedances of 1-hr and 24-hr Alberta Ambient Air Quality Objectives. Two air monitoring sites within Fort McMurray recorded mean/maximum 1-hr PM_2.5 concentrations of 291/5229 μg m^{− 3} (AMS-6) and 293/3259 μg m^{− 3} (AMS-7) during fire impact periods. High correlations (r² = 0.83–0.97) between biomass combustion related gases (carbon monoxide (CO), non-methane hydrocarbons (NMHC), total hydrocarbons (THC), total reduced sulfur (TRS), ammonia) and PM_2.5 were observed at the sites. Filter-based 24-hr integrated PM_2.5 samples collected every 6 days showed maximum concentrations of 267 μg m^{− 3} (AMS-6) and 394 μg m^{− 3} (AMS-7). Normalized excess emission ratios relative to CO were 149.87 ± 3.37 μg m^{− 3} ppm⁻¹ (PM_2.5), 0.274 ± 0.002 ppm ppm⁻¹ (THC), 0.169 ± 0.001 ppm ppm⁻¹ (NMHC), 0.104 ± 0.001 ppm ppm⁻¹ (CH₄), 0.694 ± 0.007 ppb ppm⁻¹ (TRS), 0.519 ± 0.040 ppb ppm⁻¹ (SO₂), 0.412 ± 0.045 ppb ppm⁻¹ (NO), 1.968 ± 0.053 ppb ppm⁻¹ (NO₂), and 2.337 ± 0.077 ppb ppm⁻¹ (NO_X). A subset of PM_2.5 filter samples was analyzed for trace elements, major ions, organic carbon, elemental carbon, and carbohydrates. Sample mass reconstruction and fire specific emission profiles are presented and discussed. Potential fire-related photometric ozone instrument positive interferences were observed and were positively correlated with NO and NMHC.

[en] The anthropogenic emission and subsequent deposition of heavy metals including mercury (Hg) and lead (Pb) present human health and environmental concerns. Although it is known that local and regional sources of these metals contribute to deposition in the Great Lakes region, it is difficult to trace emissions from point sources to impacted sites. Recent studies suggest that metal isotope ratios may be useful for distinguishing between and tracing source emissions. We measured Pb, strontium (Sr), and Hg isotope ratios in daily precipitation samples that were collected at seven sites across the Great Lakes region between 2003 and 2007. Lead isotope ratios ("2"0"7Pb/"2"0"6Pb = 0.8062 to 0.8554) suggest that Pb deposition was influenced by coal combustion and processing of Mississippi Valley-Type Pb ore deposits. Regional differences in Sr isotope ratios ("8"7Sr/"8"6Sr = 0.70859 to 0.71155) are likely related to coal fly ash and soil dust. Mercury isotope ratios (δ"2"0"2Hg = − 1.13 to 0.13‰) also varied among the sites, likely due to regional differences in coal isotopic composition, and fractionation occurring within industrial facilities and in the atmosphere. These data represent the first combined characterization of Pb, Sr, and Hg isotope ratios in precipitation collected across the Great Lakes region. We demonstrate the utility of multiple metal isotope ratios in parallel with traditional trace element multivariate statistical modeling to enable more complete pollution source attribution. - Highlights: • We measured Pb, Sr, and Hg isotopes in precipitation from the Great Lakes region. • Pb isotopes suggest that deposition was impacted by coal combustion and metal production. • Sr isotope ratios vary regionally, likely due to soil dust and coal fly ash. • Hg isotopes vary due to fractionation occurring within facilities and the atmosphere. • Isotope results support conclusions of previous trace element receptor modeling

[en] Mechanisms of particulate matter (PM)-induced cardiotoxicity are not fully understood. Direct translocation of PM-associated metals, including zinc, may mediate this effect. We hypothesized that following a single intratracheal instillation (IT), zinc directly translocates outside of the lungs, reaching the heart. To test this, we used high resolution magnetic sector field inductively coupled plasma mass spectrometry to measure levels of five stable isotopes of zinc (⁶⁴Zn, ⁶⁶Zn, ⁶⁷Zn, ⁶⁸Zn, ⁷⁰Zn), and copper in lungs, plasma, heart, liver, spleen, and kidney of male Wistar Kyoto rats (13 weeks old, 250-300 g), 1, 4, 24, and 48 h following a single IT or oral gavage of saline or 0.7 μmol/rat ⁷⁰Zn, using a solution enriched with 76.6% ⁷⁰Zn. Natural abundance of ⁷⁰Zn is 0.62%, making it an easily detectable tracer following exposure. In IT rats, lung ⁷⁰Zn was highest 1 h post IT and declined by 48 h. Liver endogenous zinc was increased 24 and 48 h post IT. ⁷⁰Zn was detected in all extrapulmonary organs, with levels higher following IT than following gavage. Heart ⁷⁰Zn was highest 48 h post IT. Liver, spleen and kidney ⁷⁰Zn peaked 4 h following gavage, and 24 h following IT. ⁷⁰Zn IT exposure elicited changes in copper homeostasis in all tissues. IT instilled ⁷⁰Zn translocates from lungs into systemic circulation. Route of exposure affects ⁷⁰Zn translocation kinetics. Our data suggests that following pulmonary exposure, zinc accumulation and subsequent changes in normal metal homeostasis in the heart and other organs could induce cardiovascular injury

[en] The Cleveland airshed comprises a complex mixture of industrial source emissions that contribute to periods of non-attainment for fine particulate matter (PM_2.5) and are associated with increased adverse health outcomes in the exposed population. Specific PM sources responsible for health effects however are not fully understood. Size-fractionated PM (coarse, fine, and ultrafine) samples were collected using a ChemVol sampler at an urban site (G.T. Craig (GTC)) and rural site (Chippewa Lake (CLM)) from July 2009 to June 2010, and then chemically analyzed. The resulting speciated PM data were apportioned by EPA positive matrix factorization to identify emission sources for each size fraction and location. For comparisons with the ChemVol results, PM samples were also collected with sequential dichotomous and passive samplers, and evaluated for source contributions to each sampling site. The ChemVol results showed that annual average concentrations of PM, elemental carbon, and inorganic elements in the coarse fraction at GTC were ∼2, ∼7, and ∼3 times higher than those at CLM, respectively, while the smaller size fractions at both sites showed similar annual average concentrations. Seasonal variations of secondary aerosols (e.g., high NO₃⁻ level in winter and high SO₄²⁻ level in summer) were observed at both sites. Source apportionment results demonstrated that the PM samples at GTC and CLM were enriched with local industrial sources (e.g., steel plant and coal-fired power plant) but their contributions were influenced by meteorological conditions and the emission source's operation conditions. Taken together the year-long PM collection and data analysis provides valuable insights into the characteristics and sources of PM impacting the Cleveland airshed in both the urban center and the rural upwind background locations. These data will be used to classify the PM samples for toxicology studies to determine which PM sources, species, and size fractions are of greatest health concern. - Highlights: • PM sources in the Cleveland airshed varied across regions and with seasons. • Local industrial source impacts in the urban site were higher than the rural site. • Local industrial sources were mostly emitted from steel and coal-fired power plants. • Local industrial source impacts were associated with meteorological conditions. - The Cleveland airshed was enriched with local industrial sources but their contributions were influenced by meteorological conditions and emission source operation conditions.