It's only when I'm having trouble with it that I realize how much I like breathing. Through stinging eyes, I read two consecutive e-mail messages in my in-box from the Ministry of the Environment. And here I thought they'd forgotten about me.
"The smog advisory has been terminated by the Ontario Ministry of the Environment at 11:57 am."
Super. And the next message? "A smog advisory has been issued by the Ontario Ministry of the Environment." Time stamp: 2:55 pm.
Maybe the ministry can save everyone the trouble by just sending out periodic clean air advisories. "It is now safe to turn off your computer." They could even be tied in with all the new pro-fitness adverts. "How will you use your three hours?"
A joke? Perhaps not, given the alternative. "If there's an advisory in effect all the time, it will become irrelevant to people," says Dr. Dave Steib of Health Canada. "If it's not something that's changing from day to day, they'll start ignoring it."
Not that we're paying much attention as it is. Monday's announcement from Toronto public health that 700 people die each year from acute reactions to pollution (an additional 1,100 deaths result from chronic reactions) got some scrutiny.
But the ministry's current pollution mouthpiece, Air Quality Ontario, isn't exactly sounding the alarm. It speaks only of air "quality," not pollution. If you look at its chart on Toronto, it may seem that we have a lot of "quality," the "cause" of which is ground-level ozone.
Hurrah for ground-level ozone? You could almost be forgiven for thinking that way. After all, holes in ozone are bad, right?
But ozone is an irritant that causes inflammation in lung tissues. And "reactions that occur in lungs release chemicals that affect other systems, especially the heart," says Steib. "The effects aren't restricted to asthma."
The air quality index (AQI) uses a first-past-the-post system: once a monitored pollutant exceeds national standards, it is recorded as the sole cause of air pollution in a region.
One result is that, due to the use of a single standard that can singly represent ozone, fine particulate matter, nitrogen oxides or other pollutants, all of which have different levels of toxicity, there is no communication with the public on the actual effects of any one substance. I was certainly interested to discover that ozone affects health at any concentration above 15 parts per billion. Toronto's ozone level exceeded this - often greatly - on all but about roughly 50 days in the last two years.
But ironically while we focus on ozone (a compound catalyzed by sunlight), little attention is paid to its main ingredient and common exhaust pipe emission, nitrogen oxide, until it becomes advisory-worthy, even though most people it hospitalizes succumb before it even becomes smog.
The AQI tracks the general concentration in the air of fine particulate matter, but its makeup varies from day to day and city to city depending on weather and local industry. And different people can have widely divergent reactions to the particles, which consist of everything from soil and tire bits to heavy metals and acid aerosols - full-on blood clots for the lucky ones.
The compounded effects of these substances in our bodies also occur in the air - another nuance left out by the current warning system. "We should be looking at the synergism of the chemicals, not just lone pollutants," says Dr. David Yap of the MOE. "You're not in a chamber breathing individual chemicals."
According to Toronto public health, 95 per cent of all hospitalizations related to air pollution occur on days that don't warrant air quality advisories, days variously categorized as "fair," "good" and "very good." In other words, Toronto air makes you sick, period.
Steib and others at Health Canada are working on a new rating system. "We're trying to move from terms like 'good' and 'fair' [to] terms of health-risk level," he says. "Most of the recent evidence linking air pollution to human health suggests that there isn't a safe level."
There is also no public address system for concentrations of persistent chemicals like mercury, despite rising levels in Ontario. "Both the old and the new systems are intended to reflect short-term pollution and effects of short-term exposure," says Steib. "Things are still being worked out. If it's bad all the time, when do you warn people? It has to be a balance between getting people worried when they should be but allowing them to do their daily things."
But what if it's the daily things that are worrying you?