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Ambient concentrations of speciated mercury (Hg) have been measured at many locations across Canada. Mercury in the atmosphere is measured in three operationally-defined forms - gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and particulate-bound mercury (PBM). Under most conditions, GEM (or Hg0) is the predominant species in the air (~95-99%), while RGM and PBM concentrations are typically two orders of magnitude lower, i.e., <5% of the total atmospheric mercury concentration. Reactive gaseous mercury is thought to consist of compounds such as HgCl2, HgBr2, Hg(OH)2 although the exact composition is unknown.

Measurements of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate bound mercury on PM2.5 (referred to as PBM2.5) were collected by Environment and Climate Change Canada from August to September 2013 at the Wood Buffalo Environmental Association (WBEA) Air Monitoring Station (AMS) 13 – Fort McKay South, and at WBEA AMS 4 – Buffalo Viewpoint. Monitoring resumed at WBEA AMS 13 in September 2014 with two speciated mercury instruments and is ongoing. One speciated mercury instrument monitors GEM, GOM, and PBM2.5; the second speciated mercury instrument monitors GEM, GOM, and mercury on PM10 (referred to as PBM10). These data are the first atmospheric speciated mercury measurements to be reported in the oil sands region.

Measurements of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate bound mercury on PM2.5 (referred to as PBM) are currently collected by Environment and Climate Change Canada at a Wood Buffalo Environmental Association (WBEA) Air Monitoring Station (AMS). Preliminary, three-hour averaged speciated mercury data from the oil sands region are available for WBEA AMS 13 – Fort McKay South, located near Fort McKay, Alberta. There are no Environment and Climate Change Canada or Canadian Council of Ministers of the Environment (CCME) air quality guidelines, nor Alberta Ambient Air Quality Objectives for speciated Hg measurements. The monitoring follows the established Canadian Air and Precipitation Monitoring Network (CAPMoN) standard operating procedures.

Air emissions from oil sands development can come from a number of sources including industrial smokestacks, tailings ponds, transportation, and dust from mining operations. Air quality monitoring under the Joint Canada-Alberta Implementation Plan for the Oil Sands is designed to determine the contribution of emissions from oil sands activities to local and regional air quality and atmospheric deposition both now and in the future. Ambient air quality data include:

• Filter Pack (24-hour integrated concentrations of particle-bound SO2-4, NO-3, Cl-, NH+4, Ca2+, Mg2+, Na+, K+ and gaseous SO2 and HNO3 collected daily by the Canadian Air and Precipitation Monitoring Network)

• Total Gaseous Mercury (hourly mixing ratios measured by the Canadian Air and Precipitation Monitoring Network and Prairie and Northern Region)

• Atmospheric speciated mercury (Hg) (2-hour average concentrations of gaseous elemental Hg (GEM), reactive gaseous Hg (RGM), and Hg on PM2.5 (total particulate Hg - TPM)

• Comprehensive set of measurements collected from an aircraft (various time resolutions) covering an area of 140,000 km2 over the oil sands region

• Comprehensive set of measurements collected from the Fort McKay Oski-ôtin monitoring site

• Ozone (hourly mixing ratios measured by the Canadian Air and Precipitation Monitoring Network)

• Ozone Vertical Profiles (ozone mixing ratios as a function of height) measured by the Canadian Ozone Sonde Network

• Aerosol Optical Depth (measure of the degree to which the presence of aerosols in the atmosphere prevents the transmission of light, from the ground to the top of the atmosphere) measured as part of the AErosol RObotic CANadian (AEROCAN) network

• Satellite overpass data have a relatively high spatial resolution over the Oil Sands region to produce images and geo-referenced data of nitrogen dioxide (NO2) and sulphur dioxide (SO2) “vertical column density” (which correlates with surface concentration)

This dataset contains 2005 concentrations of total mercury (THg), gaseous elemental mercury (GEM), methylated mercury, dimethyl mercury (DMHg) in the water column of the Canadian Arctic. Mercury in the Arctic is an important environmental and human health issue. The reliance of Northern peoples on traditional foods, such as marine mammals, for subsistence means that they are particularly at risk from mercury exposure. Mercury concentrations on biological organisms have increased since the onset of the industrial age and are controlled by a combination of abiotic factors, food web dynamics and structure, as well as animal behavior.

We set out to examine possible links between climate warming and increases in mercury concentrations ([Hg]) in landlocked Arctic char (S. alpinus) in the High Arctic. Mercury concentrations vary regionally and have remained constant or increased slightly in landlocked char in lakes on Ellesmere Island and Cornwallis Island over a 12-16 year period. This, despite declining industrial mercury emissions in North America. Therefore, we hypothesized that climate warming might increase the input of mercury from catchments through permafrost melt, leading to greater associated body burden of adult char.

Trace gas data sets measured by Canadian and U.S. ground-based monitoring networks from 1982 to the present including non-methane hydrocarbons (NMHC), ozone (O3) and total gaseous mercury (TGM). Included are Canadian federal and provincial networks (past and present) and U.S. historical networks (for data not available elsewhere). These data sets are associated with various networks that monitor a variety of trace and reactive gases. Non-Methane Hydrocarbons were measured and monitored in a study at Egbert, Ontario at the Centre for Atmospheric Research and Experiments, CARE.

Kejimkujik National Park, in Nova Scotia, Canada, is a sensitive region for heavy metal contamination, such as mercury, in part due to long-range atmospheric deposition from global and regional industrial regions. The region is remote from industrial centres, but is downwind of major pollution sources in North America and Canada, and historically had numerous gold mining sites. The region has also experienced anthropogenic acidification from sulphate deposition over the 20th century, which has resulted in limnological conditions favourable for mercury (Hg) methylation within Kejimkujik lakes. Kejimkujik is therefore known to be a hotspot for methylmercury (MeHg) bioaccumulation and biomagnification, with the highest mercury concentrations detected within common loon (Gavia immer) populations across Canada and North America.

Recent and historical deposition of mercury (Hg) are examined over a broad geographic area from southwestern Northwest Territories to Labrador and from the U.S. Northeast to northern Ellesmere Island using dated sediment cores from 50 lakes (18 in midlatitudes (41-50 degrees North), 14 subarctic (51-64 degrees North) and 18 in the Arctic (65-83 degrees North)). Objectives were to quantify latitudinal and longitudinal trends of anthropogenic mercury deposition in eastern and northern North America, to investigate variations in mercury deposition, to examine relationships with lake area, catchment/lake area ratio and sedimentation rates, and to compare results with model predictions. Distinct increases of mercury over time were observed in 76% of Arctic, 86% of subarctic and 100% of midlatitude cores. Subsurface maxima in mercury depositional fluxes were observed in only 28% of midlatitude lakes and 18% of arctic lakes, indicating little recent reduction of inputs.

Mercury is a naturally occurring element that is also present in the environment as a result of human activities. Water bodies can be contaminated with mercury from industrial sources, such as pulp and paper mills, and from the soil when large reservoirs are created by hydro-electric dams. Methyl mercury is considered the most toxic form of mercury to human health and is formed when bacteria interact with mercury present in water and plants. Methyl mercury accumulates up the food chain, and predatory fish generally represent the main source of exposure from the diet.