Something in the Air

We spend about 90 per cent of our lives indoors, mostly in our homes. And that, says Trevor VandenBoer, is why we need to learn more about the quality of the air we breathe while at home.

A scientist who previously focused on the quality of the air outside (a current project involves quantifying contaminants affecting whales), VandenBoer is now adding indoor air to his agenda, thanks to a US$275,000 grant from the Alfred P. Sloan Foundation’s Chemistry of Indoor Environments program and his membership in a collaboration called the New Home Air Quality Study.

“The Sloan Foundation identified indoor air quality as a topic that wasn’t being covered in terms of its high potential social impact,” says VandenBoer, assistant professor of analytical environmental chemistry in York’s Department of Chemistry. “It’s a strange phenomenon to observe and get funding for because it sits at the intersection of human health and physical science.” 

But, conversely, that intersection is why indoor air quality is important.

“Think about our lifestyles in Canada, with our harsh winters,” he adds. “We’re indoors a lot. We want to make sure that the air we’re breathing inside is good for our long-term health and well-being.”

While much work has been done to measure outdoor air quality with initiatives like the Air Quality Health Index, “there’s a lot left to learn about indoor air,” VandenBoer says. The focus now is on determining the fundamentals of what goes on indoors and how to quantify that chemical activity.

The chemistry of an indoor space comprises molecules that are too small to see with the naked eye but can have a serious effect on health, given that we take an average 25,000 breaths a day. Where do those molecules come from? The list is long – everything from deodorants to paints to vinyl flooring to gas stoves. Even cats give off ammonia. And then there are the viruses humans spread indoors, like the one that has snarled global society for almost two years now.

VandenBoer says early research on indoor air quality focused on work settings such as offices and classrooms. “If, for example, the ventilation in a classroom is not good or if the outdoor air quality being brought indoors is poor, you can wind up with a decrease in cognitive performance.”

Scientists, including those at York, are now building from that kind of knowledge to “understand if the basics of indoor air quality are the same as what we typically consider for outdoors. Or are they different? We’ve realized there’s a lot to learn.”

VandenBoer’s research through the Sloan grant is investigating ways to measure the presence of reactive nitrogen species in homes. These include gases like nitrogen dioxide and ammonia. Overexposure to both can potentially pose serious risk to health.

The analysis he and his York team are doing will contribute to the New Home Air Quality Study, which includes researchers from Health Canada, the University of Toronto, the National Research Council of Canada, Lawrence Berkeley National Laboratory, and Environment and Climate Change Canada.

“Health Canada has the mandate to provide guidance to people who build homes and make construction materials on what can and cannot be emitted from those materials for health. I’m happy to be part of this group and look forward to contributing to what we can learn.”

And he has practical advice that will be of use to people who live in new or older homes: think about how you prepare your food. “Cooking,” he says, “is one of the most intense sources of pollutants indoors. It emits a lot of compounds we should avoid.”

His recommendation? If you’re using a gas stove, be careful. The combustion gives off nitrogen dioxide. Exposure can cause or exacerbate respiratory illnesses. And with gas or electric stoves, get a good range hood installed. In addition to eliminating odours and smoke from cooking, the range hood will expel the pollutants out of your home.

Beyond the range hood, all ventilation is essential for expelling pollutants from a building and bringing in fresh air. As VandenBoer notes, “We want our homes to be airtight so they’re energy efficient. But the energy that goes into ventilating, heating and cooling these spaces is enormous, and that has a huge impact on climate change.”

That’s another reason he feels the upcoming research will be important.

“We’re trying to find the sweet spot between those two,” he says. “That’s going to be something specialists like me, as well as building engineers and operators, are going to spend a lot of time investigating over the coming years.”  ■