Overview: From the perspective of pollution from toxic fine particulate matter (PN2.5), Eastern Ontario’s air quality for the first five months of 2026 remained within the hazard zone (5.6 µg/m3). That is more than 12% above the WHO-recommended limit of 5.0 µg/m3 and, as you can see from the chart on our Health Impacts page, is at the threshold of causing increased mortality. PM2.5 levels had exceeded that limit in 55 of the past 77 months, often much worse. The April and May reduction was mostly attributable to fewer southern US wildfires, the root cause of which was fossil-fuel-driven climate change. As always, the United States’ consistent refusal to adequately regulate its fossil fuel industries is literally killing Canadians. Given that we have absolutely no levers to influence the behavior of the perpetrators, all we can do is to limit how much of their pollution gets into our lungs by taking some of the measures suggested in our Self-protection page. Do you know others who might benefit from more awareness of the reality of our air quality and how they can better protect their health? If so, please share this link: https://kingstonairquality.ca.
by Ron Hartling
The purpose of this site is to raise awareness of the uncomfortable reality that, with respect to fine particulate matter (PM2.5), Kingston air quality is consistently worse than the World Health Organization (WHO) standard. The site gives practical advice on managing household exposure to health-damaging particulates. Updates are posted daily around 7 am but the satellite view below shows the current Kingston reading at any time of day. If you live elsewhere, just click at your location on the map. For ease of personal decision-making, overall daily risk levels are categorized by severity in the table to the right.
Note that, while most Canadian and US sources define Risk Level 1 as airborne fine-particulate-matter (PM2.5) concentrations less than 12 micrograms per cubic meter (µg/m3), I employ “Level 0” to differentiate readings within the far more evidence-based, less politically-influenced WHO healthy zone. Click on the Health impacts page for clarification on the critical differences between short- and long-term exposure risks.
Commentary as of Monday June 15 at 6:45 am
Yesterday’s readings: Kingston’s official readings fluctuated around the Level-0/Level-1 boundary for most of yesterday, between 4 and 7 µg/m3 for a daily average of 4.8 µg/m3. That was identical to Saturday’s average. Overnight readings were a constant 3 µg/m3.
Forecast for today: Kingston readings are likely to vary within the comparatively unhealthy Level-0 range all day today and into tomorrow.
Detailed forecast: Environment Canada’s 24-hour Kingston forecast calls for a mix of westerly and southwesterly winds for the entire period. In the absence of the high-altitude Jetstream, that will hopefully keep Eastern Ontario within a healthy airflow. The sole risk, as you can see from the satellite view, is the Level-1/Level-2 particulate cloud south of Lake Michigan, which the southwesterly intervals could bring closer to our area.
Personal protective measures: No such measures should be required either today or tomorrow.
As of 6:30 am, this satellite view of PM2.5 fine particulate flows over North America showed significantly-improved air quality over most the eastern half of the continent thanks to strong westerly airflows which had blown most of the toxic southern US emissions out over the Atlantic. Eastern Ontario is benefitting from an especially clean flow.
Summary of recent readings
This table summarizes and provides context for the most recent three weeks of Kingston PM2.5 airborne fine particulate readings. The key numbers are, of course, the daily averages because that’s what informs us how our recent exposures have contributed to or ameliorated whatever annual exposure to toxic particulates we are comfortable with or accepting of. For those who choose to lower their at-home exposure in order to better protect their and their households’ long-term health, the numbers provide important information on how much effort may be required to stay within their comfort levels.
To facilitate that analysis, the table also computes each day’s risk category (usually a mix of 0’s, 1’s and 2’s), as well as 7- and 28-day running averages and medians. It also reports on the minimum and maximum readings for each day, as well as on the number of hours that day during which Kingston PM2.5 readings may have exceeded either or both the World Health Organization’s recommended maximum and the seriously outdated and therefore misleading US/Canadian equivalent.