While well known to medical experts, the very serious short- and long-term health risks caused by fine airborne particles are largely unknown to most people who, after all, have no alternative but to keep breathing regardless of air quality.  Because protecting oneself from chronically high airborne concentrations is feasible but requires time, effort and some money, it will be essential to provide credible evidence based on official sources to better document the reality and extent of the threat, and to clearly demonstrate the feasibility of finding even partial solutions which Ontarians can use to better protect themselves and their families.  The following tables are the result an initial analysis of 2020 through 2023 official Ontario government hourly particulate readings downloaded from the Ministry of the Environment’s Air Quality Ontario website, coupled with hourly wind direction data downloaded from Environment Canada’s weather site.  The focus throughout is on fine particulate matter, which is only one of the airborne pollutants used to calculate Ontario’s official Air Quality Index.  The reason for that narrow focus is two-fold: it is arguably the most deadly in term of threating the long-term health of Ontarians and it is the only one for which the average person can reasonably manage their exposure.

The unit of measurement (PM2.5) for each of the above tables is the mass in micrograms of airborne fine particles sized 2.5 microns or less in eachcubic meter of the outside air being measured. Those automated readings are taken hourly at 38 sensor stations across Ontario.  Kingston hosts one of those sites.

The first (Municipality) chart provides an important starting point for analysis by demonstrating that generally unhealthy air which exceeds the WHO-recommended maximum annual exposure (daily average measured over a year no greater than 5 µg) was already the Ontario norm by 2022.  This is therefore an Ontario-wide threat. Given that the 2022 wildfire season was a mild one, the readings mostly represent the sum of two components: particulates emitted in that municipality’s surrounding area and windborne pollutants from other parts of Ontario, Canada and North America. Since Kingston and Belleville have relatively few major industrial emitters, most of their airborne PM2.5 concentrations would come from elsewhere.  The Ottawa region, while a major centre, is as expected not much higher because its economy is also overwhelmingly non-industrial.

The next three tables take different approaches to estimating the degree to which emitted particulates are industrial as opposed to residential and commercial in origin.  Were the latter significant contributors, it would be reasonable to expect a very considerable difference between weekday and weekend emissions, whereas the reality is that they differ by little more than 10%. Likewise the time-of-day table. Were local, non-industrial emissions a significant component of the particulates in the air Kingstonians breathe, the levels should see a major nighttime drop while most people are asleep and most businesses and institutions closed. But there is none.

The seasonality table is a bit more difficult to interpret. The column which excludes 2023 year-to-date readings, is somewhat more clear because it is unaffected by this year’s extraordinary (but likely new-normal) June and July wildfires.  The underlying pattern appears to be slightly higher monthly averages during the North American heating season (because most homes remain heated by fossil fuels) and during the previously-normal wildfire season.

In totality, the data suggest that a baseline, year-round level of on the order of 4.5 µg/m3 PM2.5 pollutants is generated by large-scale industries which operate on a 24/7 basis.  On top of that, as evidenced by the much higher average reading in centres like Toronto and Hamilton, are the emissions from regional industries, commercial, residential and transport activities.  Then, during wildfire season, the resulting smoke clouds add a third load of toxic air.

After the June smoke peak, I attempted to predict Kingston PM2.5 readings based on the national smoke model’s prediction and found surprisingly high Kingston readings even on days during which the smoke map showed clear air overhead.  Eventually, I noticed a correlation with wind direction which, after downloading 2022 weather data from Environment Canada, I was able to definitively correlate with Kingston particulate levels.  That table demonstrates a strong correlation whereby our air quality is much better when air flow is coming from generally northern directions and much worse during southerly flows.  That finding is quite consistent with this US EPA interactive map of PM2.5 concentrations.  Their “Good” (no colour) is anything under the highly inadquate US 12µg level, and their “Moderate” (yellow) covers what we would consider moderate to unhealthy for at-risk. In my recent observations, much of the Eastern USA and the more southerly portions of  Ontario and Quebec are usually painted in an unhealthy yellow. That’s what comes our way whenever our wind direction is from the south, southeast and sometimes east.

The above analysis is generally supportive of some of the key arguments in my parent Air Quality page, that:

  • Kingston air, while somewhat better than the norm for medium-to-large Ontario municipalities, is actually unhealthy to breathe given that it consistently exceeds recommended WHO maxima;
  • The vast majority of those pollutants are outside of our control, which in turn implies that, apart from pressing senior levels of government to decisively invest in suppressing wildfires, it is mostly up to individual Kingstonians to better inform themselves and take rational measures to limit the quantities of airborne particulates which they actually breath into their lungs;

Given that such measures cost money and require that we exercise more control over our living spaces than is realistically available to the vulnerable sectors in our community, I would strongly argue that we have a moral obligation to find practical ways to help those Kingstonians protect their health as well.