Air Quality in Ontario 2017 Report

2017 highlights

Based on the Air Quality Health Index categories, Ontario reported air quality in the low risk category 94.6% of the time in 2017.

The provincial Ambient Air Quality Criteria for nitrogen dioxide, sulphur dioxide and carbon monoxide were not exceeded at any of Ontario’s Air Quality Health Index ambient monitoring stations in 2017.

As in previous years, ozone and fine particulate matter, the main components of smog, remain a concern as some areas of Ontario continued to exceed the provincial Ambient Air Quality Criterion and reference level.

The Canadian Ambient Air Quality Standards for fine particulate matter were not exceeded at Ontario’s designated reporting sites for 2017. Five of Ontario’s designated reporting sites met the Canadian Ambient Air Quality Standard for ozone for 2017.

Volatile organic compounds reported at seven Ontario Ambient Air Quality Health Index monitoring stations include benzene, toluene, ethylbenzene, xylene, and 1,3-butadiene. Ontario’s Ambient Air Quality Criteria for these volatile organic compounds (where applicable) were met in 2017 apart from benzene.

10-year trends

Overall, air quality in Ontario has improved significantly over the past 10 years due to substantial decrease in harmful pollutants such as nitrogen dioxide and sulphur dioxide that are emitted by vehicles and industry.

There has also been a significant decrease in fine particulate matter which is emitted directly into the atmosphere as a by-product of fuel combustion or formed indirectly in the atmosphere through a series of complex chemical reactions. Fine particulate matter includes aerosols, smoke, fumes, dust, fly ash and pollen, and can have various negative health effects, especially on the respiratory and cardiovascular system.

Notes:

• Nitrogen dioxide (NO₂) is the concentration measured and nitrogen oxides (NO_x) are the emissions estimated.
• Ozone is a secondary pollutant. It is not directly emitted and only formed when NO_x and volatile organic compounds react in the presence of sunlight; therefore, emission trends are not available.

Select volatile organic compounds (benzene, toluene, ethylbenzene, xylene, and 1,3-butadiene) examined in this report have decreased over the past 10 years in Ontario.

The continued decrease in these pollutants is due in part to Ontario’s air quality initiatives such as:

• Setting new and updated air standards through the local air quality regulation (O. Reg. 419/05) has helped to limit the concentration of pollutants that are of concern to human health and the environment.
• Regulating industrial emissions through the site-specific standard and technical standard compliance options under O. Reg. 419/05 which help industry to identify key sources of emissions and to take steps to decrease emissions to improve local air quality.
• Establishing emissions controls at Ontario smelters through site-specific standards under O. Reg. 419/05. These standards require Ontario smelters to operate responsibility under a set of rules that are publicly transparent (i.e. public consultation). The standards ensure facilities are managing their emissions and applying the best available technology or operational practices to manage emissions.
• The introduction of nitrogen oxides and sulphur dioxide emissions regulations (O. Reg. 397/01 and O. Reg.194/05) in the early 2000s. The regulations helped to reduce pollution in communities close to industries that emit these chemicals, particularly in the early days of the program.
• The phase-out and banning of coal-fired generating stations, beginning in 2001. The ban not only helped reduce the number of harmful contaminants entering the air, but it was also one of the largest greenhouse gas reduction initiatives in North America. This action contributed to a reduction of smog days from a peak of 53 in 2005 to zero in 2017.
• Drive clean testing of vehicle emissions was effective at reducing vehicle pollution, however vehicle standards have significantly improved since the program was created in 1999. A new, enhanced program will focus on heavy-duty diesel vehicles like commercial transport trucks and will ensure that Ontario continues to lead Canada in reducing harmful smog-causing pollutants.

As outlined in our Made-in-Ontario Environment Plan released in November 2018, we are committed to protecting our air, ensuring we have strong environmental standards that are protective of human health and the environment, and taking action to enforce local air quality standards. Looking forward, we have identified five areas for action as part of our Environment Plan to protect Ontario’s air quality:

• improve air quality in communities by creating unique solutions to their individual challenges
• reduce emissions from heavy-duty vehicles and strengthen on-road enforcement of emissions standards
• improve understanding of different sources of air pollution and their impact
• strengthen collaboration on addressing air pollution that comes from outside of Ontario’s borders
• focus on real-time monitoring to inform the public about Ontario’s air quality and protect public health

We are working with the public, First Nations and industry to drive sustainable actions and strategies that better protect air quality and address the unique challenges in communities across Ontario.

Introduction

This annual report, the 47^th in a series, summarizes the state of ambient air quality in Ontario during 2017 and examines 10-year trends. It reports on the levels of six common air pollutants measured at the Ministry’s Air Quality Health Index (AQHI) ambient air monitoring stations: nitrogen dioxide (NO₂), fine particulate matter (PM_2.5), ground-level ozone (O₃), sulphur dioxide (SO₂), carbon monoxide (CO) and total reduced sulphur (TRS) compounds, and how Ontario is performing compared to the province’s Ambient Air Quality Criteria (AAQC) that were in effect in 2017. The Ministry’s ambient air monitoring stations featured in this report are generally representative of regional air quality which is less influenced by local and industrial sources of contaminants. These air monitoring stations are sited to be representative of general population exposure and thus do not necessarily reflect air quality in source-influenced areas within a community. This report also provides an overview of the AQHI and Air Quality Alert programs in Ontario, plus the monitoring results for select volatile organic compounds (VOCs) in the province. Annual statistics, as well as 10-year trends of ambient air quality data are provided on a station by station basis in the Appendix.

This Report also provides a summary of 2017 provincial emission estimates for nitrogen dioxide, particulate matter, volatile organic compounds, and sulphur dioxide for various emission sources and associated 10-year trends. The provincial emission inventory is prepared annually by Environment and Climate Change Canada (ECCC), with input from the provinces. It is compiled from many different data sources including emissions data reported by individual facilities to ECCC’s National Pollutant Release Inventory (NPRI) combined with well documented, science-based estimation tools and methodologies to quantify the remaining emissions, because it is not possible to monitor the emissions from all the sources of the remaining emissions. The inventory is continuously updated with improved estimation methodologies, statistics and more recent and appropriate emission factors as they become available. While the provincial inventory provides valuable information on emissions within Ontario, it may not always be indicative of air quality issues which may arise from localized emissions.

Ontario continues to benefit from one of the most comprehensive air monitoring systems in North America, comprised of 39 monitoring sites across the province. Ontario’s ambient air monitoring network is part of ECCC’s National Air Pollutant Surveillance (NAPS) program which provides air monitoring instrumentation to the province. The Ministry ensures the air monitoring sites undergo regularly scheduled maintenance and strict data quality assurance and quality control (QA/QC) procedures to meet a high standard of data quality and data completeness (see the Appendix for further details).

The data, which are collected continuously at these sites, are used to:

• inform the public about Ontario’s outdoor air quality (i.e., publicly report the AQHI values and common air pollutant concentrations 24 hours a day, 7 days a week, on the Ministry’s air quality web site)
• issue health-based air quality alerts to notify the public of instances of degrading air quality (i.e., smog and air health advisories) to protect public health
• assess Ontario’s air quality and evaluate long term trends
• identify areas where outdoor air criteria are exceeded and identify the origins of pollutants
• provide the basis for air policy/program development
• better understand traffic related air pollution in highly urbanized environments and
• provide baseline information needed by academics and health practitioners to better understand the linkages between air quality and human and environmental health

In November 2018, the Ontario government released its Made-In-Ontario Environment Plan that commits to protecting our air, ensuring we have strong environmental standards that are protective of human health and the environment, and taking action to enforce local air quality standards. The data collected through Ontario’s ambient air quality monitoring network and the provincial air emissions inventory will be used to support the implementation of several key areas of action outlined in the Environment Plan, including:

• improve air quality in communities by creating unique solutions to their individual challenges
• reduce emissions from heavy-duty vehicles and strengthen on-road enforcement of emissions standards
• improve understanding of different sources of air pollution and their impact, such as through increasing and expanding road-side monitoring of traffic pollution and developing the Sarnia Area Environmental Health Project
• strengthen collaboration on addressing air pollution that comes from outside of Ontario’s borders
• focus on real-time monitoring to inform the public about Ontario’s air quality and protect public health

Further to the Ministry’s ambient air monitoring activities, there are local air quality monitoring networks operated by industrial associations in the communities of Hamilton (Hamilton Air Monitoring Network), Sarnia (Clean Air Sarnia and Area) and Sudbury (Greater Sudbury Air Quality) that provide additional air quality information for these communities.