You never really notice air quality until you're gasping for breath.
I noticed it right away when I went to China, for example. It was hard to miss the impenetrable haze that shrouded buildings, filled my mouth with cotton and nose with mucous.
I've never noticed it here in St. Albert; with rare exceptions, it's been easy breathing and clear skies. I assume that means the air's good, but I've no evidence to back that up: the city has no permanent monitoring station, and no long-term studies are available. Alberta Environment did one brief study with its mobile detector van in 2004, but that's it.
I figured I'd better fix that, so I did the first-ever passive air quality monitor study of the city.
Measuring the invisible
I asked two of St. Albert's leading air quality researchers to help. David Spink worked in Alberta Environment's air quality division for 20 years and now studies air conditions in the oilsands region. Warren Kindzierski teaches environmental health at the University of Alberta and has done many air quality studies, some of which have involved St. Albert.
Most air contains thousands of pollutants, Spink says, including radioactive particles, lead, polycyclic aromatic compounds. "Right now, we're breathing in small amounts of mercury." Since we're in a city where the only major source of air pollution is cars, he suggests I focus on those that come from burning gasoline.
Three of those pollutants are particulate matter, benzene and volatile organic compounds (VOCs). Particulate matter is the black stuff that comes out of a semi's pipes. It's small enough to clog lungs, causing asthma attacks and heart disease. You can smell the benzene around gas stations; it causes cancer. VOCs are hundreds of smog-causing chemicals from burnt gasoline or plants — you can smell them when you cut grass. They were also way too expensive for me to measure.
Instead, I hit what Spink and Kindzierski say are the big three: nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone.
SO2 causes acid rain, smog and breathing problems. You smell it when you light a match.
NO2 is the brown haze in smog. It smells foul, and makes you vulnerable to lung infections. It's made directly by burning gas and indirectly through reactions with ozone.
Ozone forms from the reaction of nitrogen oxide (NO) with volatile organic compounds. Another smog ingredient, it causes coughing, headaches and permanent lung damage. You can see it as a haze over hot roads and smell it after lightning strikes.
The experiment
I borrowed 24 passive air monitors from Edmonton's Maxxam Analytics to measure these pollutants. I mounted each head-high off the ground at 12 locations — three on St. Albert Trail, four in backyards, two in industrial parks, two by public buildings and one in the country — placing two at each site for greater accuracy. The monitors were in place from July 18 to Aug. 9.
Each monitor contained three colour-coded disks containing chemicals that reacted with NO2, SO2 and ozone. Technicians at Maxxam ran the disks through an ion chromatograph (which uses light or electricity to detect pollutants) and reported the results.
I compared the readings to data gathered over the sample period from the continuous monitoring stations at Carrot Creek and central, south and east Edmonton. (The Carrot Creek station is about 140 kilometres west of Edmonton and is representative of natural air conditions.) I also looked at the results from the 2004 Alberta Environment study.
The results
So how's our air? It's not pristine, but it's not as bad as Edmonton's.
The dirtiest site during this study in terms of total pollutants detected was St. Albert Trail south (by the tourist centre), with some 34 parts per billion of pollutant detected. (A part per billion is one drop in 520 bathtubs.) Erin Ridge and Grandin tied for least polluted, with about 22 parts per billion detected.
A quick look at traffic counts explains why. About 43,000 cars pass the Trail south spot each day, according to the city's most recent traffic count, or about six to 10 times the traffic on Erin Ridge Drive or Grandin Road. More cars meant more pollution.
The results strongly suggest those cars are making the NO2 situation worse, Kindzierski says. Erin Ridge had about three times as much NO2 as Carrot Creek, while the three Trail sites approached levels seen in east Edmonton — about nine to 10 times Carrot Creek. Again, high NO2 levels corresponded to high traffic locations.
We were probably adding more SO2 as well. Readings at all sites ranged from half to one part per billion, compared to 0.2 parts per billion at Carrot Creek. These are really low levels, Kindzierski says, so it's hard to say if these differences are significant. Sulphur levels in fuel are now very low, so you don't see much of it without heavy industry.
The results for ozone were ambiguous. All stations detected levels at or below those found at Carrot Creek, suggesting little ozone pollution.
But that might not be the case, Kindzierski notes. As ozone takes up to four hours to form, ozone-causing pollutants released here could easily have been blown away before they were detected. Nitrogen oxide also eats ozone to becomes NO2, which is why NO2-rich downtown Edmonton often appears to have less ozone pollution than Carrot Creek. I'd need to monitor a bigger area for a longer period to confirm St. Albert's effect on ozone, he says.
What to do with them
The results suggest that St. Albert is likely making the air a dirtier place to live in terms of SO2 and NO2, contributing to smog, asthma and premature death.
It's likely a small contribution. Alberta Environment's 2004 study sampled air at six locations, many of which were coincidentally close to the spots I put the samplers. It found that levels of NO2, SO2, ozone and particulate matter were all well below provincial exposure limits for health effects.
That doesn't mean it'll stay that way, Spink notes. Air pollution already causes 173 premature deaths a year in Alberta, according to a 2008 Canadian Medical Association study, and could cause about 217 deaths by 2015 if not reduced. Alberta Environment's latest air emission projections also predict rising levels of smog-causing emissions towards 2020.
Alberta needs tighter air quality standards to get these emissions under control, Spink argues. Alberta's NO2 limits are twice as high as those set by the World Health Organization, for example, and those are the ones used by Europe. "If those countries can target to meet those [with their population] we should easily be able to beat them."
St. Albert will also need a permanent air monitor to watch for health effects. The reason why the city doesn't have one is pretty simple, according to Bob Myrick, head of Alberta Environment's air policy evaluation unit: no one's complained about the air yet. "Because of the population of St. Albert, it's in a place where we're looking to place a permanent monitoring station."
Since the main source of air pollution in St. Albert is cars, we can clean our air by idling less and taking the bus more. Walkable neighbourhoods, such as those envisioned under the Smart Growth strategy, could also reduce car use.
Watch for regional threats as well, Spink says. "If there are problems in Edmonton, those problems can move to St. Albert." Local groups are now working on a regional management plan for ozone and particulate matter for this reason.
St. Albert doesn't have China-esque air yet, and hopefully never will. "It's not bad," Spink says, "but it could be better." So why not take action to protect it? "Do we want it to deteriorate?"
