Air Quality and Emissions

Levels of particulate matter



Particulate matter are microscopic airborne particles that come in either solid or liquid form. Small particles of concern include:

  • fine particulate matter, such as those found in woodsmoke, that are smaller than 2.5 micrometers in diameter (PM2.5); and
  • coarse particulate matter, such as those found near roadways and industrial activities (e.g., quarries), that are larger than PM2.5, but smaller than 10 micrometers in diameter (PM10).


Figure 1: Sizes of Particulate Matter
Source: United States Environmental Protection Agency 2016


Health effects

The size of particles is directly linked to their potential for causing health problems; smaller particles pose large health problems as these particles can more readily get deep into the lungs and potentially into the bloodstream (haikerwal et al., 2015). Fine particulate matter also stays airborne for longer periods than coarse particulate matter (as coarse PM settles to the ground faster), and are therefore associated with longer explosure periods. Exposure to particulate matter has been linked to a variety of health issues, including:

  • aggravated asthma;
  • decreased lung function;
  • heart attacks and/or irregular heartbeat;
  • premature death in people with heart or lung disease; and
  • increased respiratory symptoms, such as irritation of the airways, coughing or difficulty breathing.

The elderly, children, and people with chronic respiratory illnesses are most at risk, but even healthy people can experience temporary symptoms.

Exposure to particulate matter has been scientifically proven to be detrimental to both public health and the environment. Sources of fine particulate matter in the Yukon include:


Natural sources Anthropogenic sources
Forest fires: Although the predominant air flow is westerly (from Alaska), smoke from fires in B.C. and the N.W.T. occasionally affect Yukon’s air quality Emissions from fossil fuel burning, such as transportation, electricity generation, oil and gas
Wind-blown dust from gravel roads, especially in spring Wood burning for residential / commercial heating, land clearing, or recreational burning
Pollen Incineration or open burning of waste
Volcanic activity, sometimes from as far away as Asia. Fugitive dust from vehicles, quarrying or construction


Yukon Ambient Air Quality Standards have been developed under the Environment Act to protect human health and the environment. The Department of Environment monitors levels of PM2.5 in Whitehorse. Continuous, 24/7-monitoring of PM2.5 provides an indication of the state of, and trends in, local air quality. It is in addition to providing a point of comparison of Yukon air quality to national results.



Other environmental effects

Particulate matter may also affect the environment through:

  • High pollution levels impairing visibility, which may affect driving, aviation, and outdoor sports or recreational activities like fishing, hiking, or camping.
  • Changing nutrient and/or acidity balance in soil or water when particulate matter carried by the wind settles on the ground.
  • Black carbon, a component of PM2.5, is considered a short-lived climate pollutant (SLCP). These pollutants have a relatively short lifetime in the atmosphere—a few days to a few decades—and are generally more potent than carbon dioxide in terms of their climate warming potential.
  • Temperature inversions, when air higher in the atmosphere is warmer than air closer to the earth, can increase the impacts of particulate matter pollution. Inversions act like a cap on the atmosphere, preventing the dispersion of pollutants away from valley bottoms. In Yukon, the most heavily populated communities, Whitehorse and Dawson City, are located in valleys.


What is happening?

Annual mean levels


In September 2014, the Government of Yukon updated the Yukon ambient air quality standards to include an annual mean standard for PM2.5 of 10μg/m3.

  • Measurements taken at the Whitehorse National Air Pollution Surveillance station since 2002 have not found levels in excess of the annual mean standard for PM2.5.
  • The annual mean has steadily increased over the past five years. This could be due to a number of factors such as population growth, increase in use of wood as a heating source, or meteorological variations. Due to equipment malfunction, there is not enough data available to calculate a mean annual value for 2015.
  • Note: The NAPS monitoring station was relocated from a relatively windy site on the Yukon River to downtown Whitehorse in 2011. At the same time, a new, technically advanced higher-precision analyzer PM2.5 monitoring instrument was installed.
Figure 2: Annual mean level of PM2.5 in Whitehorse
24 hour average exceedances
Number of days/year that the 24-hour Yukon standard for PM2.5 was exceeded in Whitehorse
Year Number of days 24-hour standard exceeded
2002 0
2003 0
2004 12
2005 4
2006 N/A
2007 0
2008 0
2009 15
2010 7
2011 7
2012 19
2013 2
2014 2
2015 0

In 2014, the Yukon’s 24-hour average standard for PM2.5 changed from 30 to 28 μg/m3, in alignment with the Canadian Ambient Air Quality Standards. The table shows the number of days each year that PM2.5 exceeded the 24-hour Yukon standard in Whitehorse.

Although 2012 had more exceedances throughout the year than 2014, the extent and duration of the exceedances on the two days in February 2014 resulted in a higher monthly average (Figure 3).



Air Quality Management System


Air quality monitoring in the Hidden Valley.


The Canadian Council of Ministers of the Environment (CCME) is a 14-member council of environment ministers from federal, provincial, and territorial governments. The CCME focuses on national issues that require the collective attention of all governments.

In 2012, the CCME established the Air Quality Management System (AQMS). It is a comprehensive approach for improving air quality throughout Canada. AQMS is the product of extensive collaboration by government and stakeholders on air quality.

Air Zones:

AQMS requires the establishment of air zones within each jurisdiction. Air zones are geographical-based zones that will allow the provincial/territorial governments to manage local ambient air quality within their jurisdiction with the goal of continuous improvements in air quality. Provinces and territories, with assistance from the federal government, will beare responsible for managing each air zone within their jurisdictions and reporting to their residents on air quality and the measures taken to implement AQMS.

Yukon has a single air zone (the ‘Yukon Air Zone’) which covers the entire territory. Major anthropogenic air emissions sources in the Yukon Air Zone include emissions from fossil fuel burning (transportation, heating and power generation), wood burning, waste disposal (incineration and open burning), and fugitive dust from roads, quarrying and construction. Natural sources of particulate matter include forest fires, wind-blown dust, pollen and transboundary flows and exceptional events (e.g. overseas volcanic eruption).

Canadian Ambient Air Quality Standards:

The previously used Canada-wide standards for fine particulate matter and ground-level ozone were replaced by the Canadian Ambient Air Quality Standards (CCAQS) in 2013. The CAAQS are the driver for air quality management under AQMS and standards have been established for fine particulate matter and ozone. An air zone metric for each pollutant (PM2.5 and ozone) is calculated to determine the achievement status of a given standard and the associated management level for air quality within an air zone.

In 2016, Department of Environment reported on the achievement of the CAAQS for the years 2014 and 2015 through the publication of annual air zone reports. Air zone reports are a commitment of the Government of Yukon under the AQMS, and form the basis for monitoring, reporting and taking action on air quality issues. AQMS has established four colour-coded Management Levels (Green, Yellow, Orange and Red) to that ensure proactive measures are taken to protect air quality. The Red level indicates that the CAAQS have been exceeded, while the Green level indicates good air quality. The Management Level to which an air zone is assigned for a particular pollutant drives actions to improve or maintain air quality, with progressively more rigorous actions from Green to Red. Yearly achievement of the CAAQS is based on a running mean of three years of data; the 2014 metrics, for example, are calculated based on data from 2012-2014.

In 2014, the Yukon Air Zone’s pollutant metrics were below CAAQS exceedance thresholds. For both ozone and particulate matter, the Yukon Air Zone achieved the Yellow Management Level. The objective for the Yellow Management Level is to improve air quality using early and ongoing actions for continuous improvement. The results are presented in Table 1, below.

Table 1. Air Quality Standards and 2014 Results for the Yukon Air Zone




2014 Results

Management Level

Management Action

PM2.5 - 24-hour




Actions for preventing air quality deterioration

PM2.5 – Annual




Actions for preventing air quality deterioration

Ozone - 8-hour average




Actions for preventing air quality deterioration

2014 results for all three reporting metrics are based on two years of data instead of the recommended three years due to data loss.

In 2015, reporting for the years 2013-2015, ground-level ozone achieved a Management Level of Yellow, which is the same as the previous reported year. For particulate matter for the 2015 reporting period, there was insufficient data collected to meet the statistical requirements needed to calculate a metric; therefore, there is no calculated metric for this year.

Mobile Sources:

Mobile sources are a major contributor of air pollutant and greenhouse gas emissions in Canada. An action plan under the AQMS is being developed to reduce emissions from mobile sources in the transportation sector. The plan would include addressing vehicle tampering and encouraging the conversion of fleets to electric vehicles. Priorities are to implement advanced transportation technologies and proper vehicle maintenance, to reduce emissions from diesel vehicles and engines, and to make vehicle fleets greener.

Base-level Industrial Emissions Requirements:

Base-level industrial emissions requirements are intended to ensure that all significant industrial sources in Canada meet a good base-level performance. Performance standards will be established for new and existing major industrial sectors and some equipment types. Monitoring and public reporting is critical for transparency, accountability, and the effective implementation of AQMS.

More information on the Air Quality Management System can be found on the CCME website.

Monthly comparison of PM2.5

While the level of PM2.5 in Whitehorse can vary greatly over a year due to local meteorological events, transboundary flows, exceptional events and human activities, comparing particulate matter levels by month is helpful to give a picture of trends and seasonality of ambient fine particulate matter pollution.

  • Winter months have higher levels of particulate matter than summer months. Heating buildings from wood or fossil fuels can drive PM2.5 levels up.
  • PM2.5 can increase in summer months due to spring road dust and wildland forest fires.


Comparison to national average


  • Whitehorse PM2.5 levels have never been above the national average during the 2002 – 2015 monitoring period.
  • The national average for PM2.5 has not exceeded the annual standard of 10 μg/m3.
  • Data are available up to 2013; the 2014 and 2015national averages are not yet available from Environment and Climate Change Canada.

In 2014, the Yukon’s 24-hour average standard for PM2.5 changed from 30 to 28 μg/m3, in alignment with the recently established Canadian Ambient Air Quality Standards. The table shows the number of days each year that PM2.5 exceeded the 24-hour Yukon standard in Whitehorse. In 2015, there were no exceedances of the PM2.5 24-hour standard. The years with a higher number of exceedances of the 24-hour Yukon standard for PM2.5 likely correlate with high wildfire seasons.


Transportation can result in emissions.


Figure 3: Monthly comparison of PM2.5 in Whitehorse, Yukon
Figure 4: Comparison to national average



Taking action


  • Monitoring Yukon’s air quality occurs as part of the National Air Pollution Surveillance (NAPS) program, which monitors the quality of ambient air in urban areas and provides long-term air quality data of uniform standard across the country. A Memorandum of Understanding establishes the collaborative effort of the program between the federal, provincial, territorial and some municipal governments. Jurisdictions use the air quality data compiled by NAPS to assess and report on the state of the air and to develop programs to address priority air quality issues in air zones. Data provided by NAPS also support public information tools, such as the Air Quality Health Index and the Canadian Environmental Sustainability Indicators. NAPS data can be accessed from the Canada-wide air quality database.
  • In the spring of 2016, the Air Quality Health Index (AQHI) was launched for Whitehorse. The AQHI is a public information tool that helps Canadians protect their health on a daily basis from the adverse effects of air pollution. The AQHI is calculated based on the relative risks of a combination of common air pollutants, including ozone, particulate matter and nitrogen dioxide; the data is collected from the Whitehorse NAPS station.
  • Data provided by NAPS also support public information tools ,such as such as the Air Quality Health Index and the Canadian Environmental Sustainability Indicators.
  • The Department of Environment is currently conducting a fine particulate matter monitoring study in Whitehorse, in conjunction with Health Canada, the City of Whitehorse, the Office of Chief Medical Health Officer, Yukon Health & Social Services; Energy Mines and Resources; and Community Services. This study is collecting data from nine monitoring stations set up around the city. Data will be used to determine the levels and spatial variability of PM2.5 pollution in the various neighbourhoods, and subsequently enable partners to make decisions on actions that need to be taken in high-pollutant neighbourhoods. The results of the study are anticipated to be available in 2017.
  • The Department of Environment is also participating in a national Health Canada study: Outdoor Air Pollution Exposure and Risk Assessment. It is examining the oxidative potential of PM2.5 and the relationship with human health concerns, including lung cancer and heart attacks. Sampling at the downtown Whitehorse NAPS station began in the spring of 2016 and is expected to continue for two to three years.


NAPS station in Whitehorse.



Data quality

  • NAPS data are quality-controlled, assured, and standardized by Environment and Climate Change Canada and the Yukon Department of Environment for inclusion in the Canada-wide air quality database.
  • The Whitehorse NAPS station, located in downtown Whitehorse, continuously monitors particulate matter, nitrogen dioxide and ground-level ozone.
  • Air quality data collected at the NAPS station are not representative of air quality throughout Whitehorse or Yukon because of differences in geographical layout, population density and pollution sources.
  • Canadian Environmental Sustainability Indicators (CESI) measure the progress of the Federal Sustainable Development Strategy, report to Canadians on the state of the environment, and describe Canada’s progress on key environmental sustainability issues. The indicators, built on rigorous methodology, are added and updated as new, high quality data become available.


Further information

The Department of Environment: Air Quality

Canadian Lung Association: Outdoor Air Quality


Haikerwal A, Akram M, Del Monaco A, et al. Impact of Fine Particulate Matter (PM2.5) Exposure During Wildfires on Cardiovascular Health Outcomes. Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease. 2015;4(7):e001653. doi:10.1161/JAHA.114.001653.

United States Environmental Protection Agency. n.d. Particulate Matter (PM) Basic Information. [modified 2016 Feb 23; cited 2016 Mar 3]. Available from: http://www3.epa.gov/airquality/particlepollution/basic.html

Yukon Department of Health and Social Services. 2015. New Study to monitor Whitehorse air quality [News release]. Available from: http://www.hss.gov.yk.ca/15-344.php