Air pollution experts warn of smokier B.C. cities in future as climate changes

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      The Red Bull 400 in Whistler has been billed as the world’s steepest race, which is why competitors need not only powerful glutes but also strong lungs and a dependable heart. But this month, because of smoky air conditions, the annual run up the 37-degree incline of the Whistler Olympic Park ski jump was cancelled.

      It’s one of many consequences of the more than 900 wildfires across B.C. since April. Media outlets have reported a run on the sale of surgical masks in the wake of reports of Beijing-style air quality. There have been great acts of generosity to those who’ve been forced to evacuate their homes. And firefighters from other provinces and countries have been descending on B.C. to combat the wildfires.

      Nowadays, Metro Vancouver residents are even being treated to smoke forecasts on radio and TV newscasts. This enables them to plan their exercise schedules or take precautions if they have asthma, heart disease, or other conditions placing them at higher risk.

      Sarah Henderson, a senior scientist in environmental health services at the B.C. Centre for Disease Control, told the Georgia Straight by phone that “large smoke events” can result in a doubling, tripling, or even quadrupling of people visiting B.C. pharmacies to obtain Ventolin. Asthmatics rely on this to increase the flow of air into the lungs.

      “That’s an indicator for us that the population is definitely responding to the smoke,” Henderson said. “Approximately 10 to 12 percent of the population is asthmatic and would use that medication on a regular basis.”

      Meanwhile, the federal government’s Air Quality Health Index offers real-time air-pollution measurements on a scale from 1 to 10 in B.C. communities. This month in Metro Vancouver, the AQHI has jumped to between 7 and 10 on many occasions, indicating a “high risk” to health.

      At this level, people with heart or breathing problems are advised to reduce or reschedule strenuous outdoor activities, and kids and the elderly should be taking it easy. But it hasn’t been out of the ordinary to see far higher ratings pop up in B.C. Interior communities, signifying a “very high” risk.

      During a recent phone interview with the Straight, UBC associate professor of medicine Chris Carlsten said the rating was 49 at that time in Kamloops. “It’s higher than anything I’ve ever seen in British Columbia,” he said. “I don’t always check every single day, but now it’s 49 on a scale of 1 to 10!”

      Smoky air in Whistler led to the cancellation of the 2017 Red Bull 400.
      Brian Caissie/Red Bull

      Dirty air kills more than car crashes, suicide, and HIV

      Many British Columbians don’t realize that air pollution is a significant killer. Carlsten and UBC professor Michael Brauer wrote a chapter in a recent book, Reflections of Canada: Illuminating Our Opportunities and Challenges at 150+ Years, that noted almost 8,000 Canadian deaths per year “are related to air pollution”.

      “Air pollution causes more death than motor vehicle collisions, suicide, and HIV combined,” they declared in the book.

      In a phone interview with the Straight, Brauer pointed out that these fatalities aren’t widely recognized because “nobody gets ‘air pollution’ on their death certificate.”

      Airborne particulate matter of 2.5 microns or less in width—in either solid particles or liquid droplets—has been linked to serious health conditions. According to a May presentation by Brauer to Bloomberg Philanthropies, air pollution affects mortality and incidence of such major killers as ischemic heart disease, strokes, and acute lower respiratory infection. Air pollution also contributes to higher mortality from chronic obstructive pulmonary disease (COPD) and lung cancer.

      His presentation noted that air pollution is “possibly linked” to neurodevelopment, cognitive function, and Type 2 diabetes. As well, there’s “growing evidence” of its connection to birth outcomes and childhood respiratory disease.

      Brauer told the Straight that the immune system sends out cells to kill bacteria or viruses that come in contact with the lungs. Inorganic fine particulate matter, on the other hand, can't be killed.

      “Your body is in this heightened state of response and that circulates in our bloodstream,” he noted. “That’s certainly why we see effects on the heart. There is some evidence showing effects on the brain as well.”

      The effects of air pollution lead to chronic diseases as people get older. And with longer lifespans, Brauer said, this means that greater air pollution will result in more people living with these conditions for a longer period of time.

      UBC professor Michael Brauer is one of the world's leading authorities on the harmful impacts of air pollution.

      Prof says summer smoke is "the new normal"

      Although Canada has made great strides in improving air quality in recent decades, there are still serious issues to address.

      Brauer said air pollution is drifting across the Pacific in larger concentrations from Asia; industrial projects are resulting in lower air quality in some communities; and container ships and nonroad vehicles, such as construction equipment, are still emitting large amounts of pollutants.

      And according to Brauer, wood smoke, much of it from heating homes, already accounts for about 15 percent of the air pollution in Metro Vancouver.

      “As other things have been cleaned up, its importance has risen proportionally,” he said. “And it’s a source that’s not really giving us much of a benefit, except in ambience. So you can’t really argue that it’s driving the economy or even really helping people’s lives in a very meaningful way, except [for creating] a warm and cozy feeling.”

      Carlsten and Brauer write in Reflections of Canada, “growth in the frequency, magnitude, and severity of wildfires in Canada” is having an impact on the allocation of health-care resources. Longer forest-fire seasons in the western United States are being brought upon by climate change, according to the Union of Concerned Scientists.

      “My line for this summer is, ‘This is the new normal,’ ” Brauer said. “We’re going to see more fire-smoke events like this.”

      So will longer and more intense forest-fire seasons in the future lead to more deaths?

      Here’s how Carlsten responded: “It’s a dramatic question, but it’s a reasonable one. And I think the evidence suggests that, yes, more people will die. Now, how many people? We’re not talking nearly as many as from outdoor air pollution.”

      Carlsten and Brauer both emphasized that chronic effects of long-term exposure to particulate matter and ground-level ozone—produced when sunlight interacts with stagnant air, nitrogen oxides, and volatile organic compounds—are far more deadly than short-term, wildfire-induced spikes in poor air quality. And Vancouver's air quality is still far better on an annual basis than that in large Asian cities such as Delhi or Beijing.

      However, this shouldn’t engender complacency.

      Brauer and Henderson each pointed out that if these spikes become a regular annual occurrence over one-month or two-month periods in cities like Williams Lake, Kelowna, Quesnel, or Kamloops, this will push up annual exposure to particulate matter, which can take a toll over the long term.

      “Probably the impact [of fires] over the last month in Williams Lake has increased the monthly average to 50 micrograms per metre cubed, compared with the usual of about five,” Henderson said. “So when we average that out over the year, it’s brought up the annual average quite a bit. If that happens the next year and the year after that, then people’s long-term-exposure profile is starting to change.”

      Henderson wants people to realize that they can mitigate the effects of forest fires by having a portable air cleaner in one room of the home. This can offer a refuge from the smoke.

      She also said that the population can become more resilient by starting each summer with a supply of “rescue medications” on hand. As well, they should have a plan if they’re unable to bring symptoms of diseases like asthma under control.

      Moreover, Henderson said, municipalities should identify buildings in the community that have large air-filtration systems where people can find relief from the smoke. And hospital heating, ventilation, and air-conditioning systems must be capable of filtering out smoke from wildfires.

      Henderson also suggested that people living in communities with high summer smoke levels might want to plan vacations during forest-fire seasons to reduce their long-term exposure.

      The Harrison Lake East wildfire is one of the sources of smoke in Metro Vancouver.
      B.C. Wildfire Service

      Air pollution can affect genes

      In his lab at UBC, Carlsten studies the impact of two-hour increases in exposure to diesel exhaust on human physiology. He said that each research subject also breathes filtered air for comparative purposes.

      He has concluded that breathing air laden with diesel exhaust results in short-term increases of a type of white blood cells called neutrophils in the lungs. These are “characteristic of inflammation”.

      Carlsten also said that proteins called cytokines and chemokines in the lungs and the blood can “reflect this inflammation” by sending signals to other cells involved in allergic reactions and immunology. In addition, metabolites of these proteins have been detected in urine of those exposed to diesel exhaust. This shows that they’ve travelled through the blood and kidneys before being filtered out of the body.

      Carlsten said that he has even observed temporary chemical modifications to genes after exposure to diesel exhaust.

      An Ontario epidemiological study published in the Lancet earlier this year showed an association between people living near a highway or major road and dementia. Carlsten, however, emphasized that it’s hard to determine if this was “truly causal” or whether another variable might explain this result.

      In the meantime, Carlsten’s lab hasn’t found any indication of loss of brain function when subjects have been exposed to two hours of diesel exhaust.

      “We did a computerized test of cognition—delays in reaction times, the kinds of things that are tested in the alcohol [scientific] literature—to see if you’re slow to react to a one-millisecond level,” he said. “None of those changed. But we haven’t analyzed the functional MRI [data] yet because it’s a lot of work to process those images.”

      He also acknowledged some “subtle differences” between the effects of wood smoke and diesel exhaust.

      “For example, the cardiac effects of wood smoke do not seem to be as strong, relatively speaking, compared to traffic at the same levels,” he said. “We don’t totally understand why, but they’re in the same general ballpark.”

      In addition, Carlsten revealed that there are different air-quality impacts depending on what species of trees are burning and whether the wood is wet or dry. His lab has started doing pilot studies with wood smoke because he feels it’s important to gain a better understanding of this issue.

      “As these fires become more and more common—and everything suggests they will be more and more common in our province—we want to study it ourselves,” Carlsten explained. “Traffic pollution is actually getting better and forest-fire pollution is getting worse.”

      It’s a timely field of inquiry, given what’s happened in B.C. in the wildfire-laden summer of 2017.

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