Overview: From the perspective of pollution from toxic fine particulate matter (PM2.5), Eastern Ontario’s air quality for the first six months of 2026 remained within the hazard zone (5.8 µg/m3). That is 16% above the WHO-recommended limit of 5.0 µg/m3 and, as you can see from the chart on our Health Impacts page, has crossed the threshold for causing increased mortality among Kingstonians. Kingston’s PM2.5 levels had exceeded that limit in 56 of the past 78 months, often much worse. More northerly wind directions in April and May kept south of the border some of the US industrial emissions which constitute most of Eastern Ontario’s air pollution, but that pollution returned in June with the reversion to mostly southwesterly airflows. Northern Canada’s wildfire season got off to a late start at the end of June and the resulting smoke plumes had yet to reach Eastern Ontario by Canada Day. That can be expected to change for the worse, with northern smoke plumes arriving from what may well be one of the worst wildfire seasons on record. What we can also expect, once Canadian wildfire smoke arrives over US cities, is for a repeat performance of hypocritical American legislators holding press conferences on pressuring Canada to do a better job of combatting wildfires, totally ignoring the fact that Canadians’ annual exposure to US industrial emissions vastly exceeds what they get from our wildfires, not to mention the reality that their refusal to adhere to global restrictions on the carbon emissions which are the root cause of those fires. Given that we have absolutely no levers to influence US-generated pollution, all we can do is to limit how much 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 Sunday July 26 at 6:40 am
Yesterday’s readings: As predicted, Kingston’s official PM2.5 readings yesterday again remained within the moderately-unhealthy Level-1 range, from 5 to 8 µg/m3 for a daily average of 6.5 µg/m3, up from Friday’s 5.6. Overnight readings climbed to between 9 and 11 µg/m3.
Forecast for today: Today’s readings should mostly fluctuate within the upper half of the Level-1 range, with some Level-2 periods possible later in the day.
Detailed forecast: Environment Canada’s 24-hour Kingston forecast calls for continuing southwesterly winds for the remainder of today, calming overnight. The high-altitude Jetstream, however, will be curving northwesterly over the western Great Lakes but somewhat distant from Eastern Ontario. Our area is therefore likely to receive US industrial emissions for the entire day. As you can see from the satellite view, we remain on the path of some of the more unhealthy Level-2 concentrations. The 72-hour Ontario wildfire smoke plume maps again predict no smoke plumes our area within that period. The UBC Firesmoke model shows only 52 wildfires burning across Canada, much fewer than yesterday at this time. By contrast, the US, whose Republican politicians love to complain bitterly about Canadian smoke crossing the border, have 120 burning.
Personal protective measures: Such measures will hopefully not be needed by most people today.
As of 6:00 am, this satellite view of PM2.5 fine particulate flows over North America showed Eastern Ontario to be embedded within a long, unhealthy, diagonal band of mostly Level-2 US airborne pollutants stretching all the way from Texas to the Gulf of St. Lawrence. Overall air quality is poor for most of the continent.
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.