by EVAN MATTHEWS
With Valemount having had five Provincially issued air quality advisories dating back to November, the Province confirmed Valemount consistently ranks near the bottom in terms of Provincial air quality during winter months.
Gail Roth, air quality meteorologist for the B.C. Ministry of Environment, issues the advisories.
Valemount’s air quality advisories are often linked to wood stoves — which are the valley’s number one source of an air pollutant called particulate matter, according to Roth — along with vehicle traffic, and thermal inversions contributing to the issue.
Thermal inversions
Thermal inversions are common in B.C. because of the mountain valley-terrain, according to Roth. If a town is situated in a valley the way Valemount is, colder air is “stuck” down in the bottom of the valley, while warmer air sits up top.
Unfortunately, the warm air cannot disperse due to the surrounding mountains, Roth says, so whatever activities people are doing in the valley, in combination with environmental conditions, causes pollutants to accumulate, and the air lingers until the weather system changes and flushes the air along with its pollutants out of the valley.
Monitoring the air
Roth monitors Valemount’s air quality, and based on weather patterns, combustible emissions and human activity, issues advisories as needed.
“Continuous analyzers”, according to Roth, take measurements of various pollutants in the air at any given time, with the main pollutant in Valemount being called “particulate matter”, or PM.
“There’s a number of ways you can measure pollutants in the air,” says Roth. “Valemount has Continuous (Ambient Air Quality) Analyzers… they continuously collect data,” she says.
Particulate matter
Particulate matter is airborne particles in solid or liquid form, according to Environment and Climate Change Canada.
There are two categories of Particulate Matter, according to Environment and Climate Change Canada, one being PM10, which is particulate matter with a mass median diameter less than 10 micro metres. The second category is PM2.5, which is particulate matter with a mass median diameter less than 2.5 micro metres.
“Ten micro metres in diameter is smaller than a human hair,” says Roth. She notes the Ministry measures PM2.5 in Valemount.
PM10 is generated, generally, by mechanical forces such as road dust ground up by vehicles and kicked up into the air, or by natural occurrences like pollen, Roth says, while PM2.5 is mainly derived from combustion based sources such as vehicle exhaust, residential wood smoke, industrial emissions, etc.
“When we say fine particulate matter (PM2.5), we’re measuring what we call the respirable fraction — you can breathe those into your lungs,” she says.
At its worst
During a six-day air quality advisory in Valemount, which lasted from Dec. 7 through Dec. 12, the air quality — at its worst — was listed as hazardous.
On Dec. 7 the air in Valemount was nearly twice as bad as Beijing’s, though Roth made sure to note this isn’t consistent and isn’t really a fair comparison, as Beijing has some of the worst air quality in the world on a consistent basis.
“We have to keep things within a reasonable perspective,” she says.
Even during the winter months, it is rare for Valemount’s air quality to get as bad as Beijing’s.
“If you’re exercising and eating healthy, you’ll be much better off (in a place like Valemount) than if you were not exercising and eating healthy, while living in a city free of air pollution,” – Gail Roth, air quality meteorologist for B.C.’s Ministry of Environment
In context
So is it time for Valemount residents to panic? Maybe not, but there is still a reason to care in the context of general health.
“It’s certainly not the same type of effect, as say, if you are a smoker,” says Roth.
“Air quality falls in the middle of conditions (potentially) impacting people’s health.
“For example, if you’re exercising and eating healthy, you’ll be much better off (in a place like Valemount) than if you were not exercising and eating healthy while living in a city free of air pollution,” she says.
Though it isn’t a doomsday type situation, Roth says air quality affects everybody, and is therefore important to monitor.
Air quality data obtained from the Ministry of Environment show there were 37 days in Valemount between Dec. 2015 and Dec. 2016 when the concentrations of PM2.5 was above the Provincial air quality objective of 25 micrograms per cubic metre.
The B.C. Government’s air quality objective means PM2.5 should make up no more than 25 micrograms in a cubic metre over a 24-hour period, according to Roth, but if PM2.5 exceeds 25 micrograms in a cubic metre over a 24-hour period, the Province usually issues an air quality advisory, she says.
However, if the PM2.5 is no longer exceeding 25 micrograms in a cubic metre during hour 25, the Ministry may not necessarily issue an advisory, as by that point the hazard has passed.
During the Dec. 6th to 12th advisory, there were 48 individual hours with a concentration above 100 micrograms per cubic metre, which is five times the provincial objective. 15 hours had concentrations above 299 — 12 times the provincial objective.
Who’s affected?
“These numbers are getting high enough that people with respiratory conditions like asthma, or people with (heart) disease are more are at a higher risk for complications,” says Roth.
“But air quality can have acute (short-term) or more chronic (long-term) affects,” she says.
Air quality can trigger an episode or force those affected to rely on medications in the short-term, according to Roth, but she says health researchers are finding people who are exposed to poor air quality over long periods of time are having a chronic inflammatory response.
“Your body is trying to fight the particles trying to get into your body, like it would a cold,” says Roth.
“It causes chronic inflammation, and if you have chronic inflammation it can be a pre-cursor to other disease and push you over the top to experience those issues,” she says.
The data also shows yearly concentrations of PM2.5 in Valemount are above the yearly guidelines by the World Health Organization. Valemount’s yearly concentration this past year was 12 micrograms per cubic metre, above the guideline of 10.
What can you do?
The Province is aware people have limited heat sources in rural towns like Valemount and that there aren’t many alternatives at this point, Roth says, but the Province does have a solution available.
A wood stove exchange program, which allows users to trade in an old wood stove for a rebate in order to upgrade their technology to the most efficient and up to date wood stoves.
“Managing air quality will always be a challenge,” says Roth. “It’s just a reality of the topography, the heat sources, etc. It’s all the more reason to educate the public on how to reduce it and make it better.”
