University professors say declining global air quality is putting public health at risk

Professors from Dalhousie and Saint Mary’s universities say there are high levels of PM2.5 and carbon dioxide in the air which, in the long run, lead to cancer.

By Sara Connors

Skyline view of Halifax. The city's air could be at rise according to Martin and Clyburne.
Skyline view of Halifax. The city’s air could be at risk according to Martin and Clyburne.

Public health may be at risk due to declining levels of air quality, say two professors from Dalhousie and Saint Mary’s universities.

Randall Martin of Dalhousie’s physics and atmospheric science departments and Jason Clyburne of Saint Mary’s chemistry department held a lecture on global air quality at the Museum of Natural History Monday night. They say high levels of PM2.5, and carbon dioxide, which The United States Environmental Protection Agency says is more than 15 micrograms, has been detected in the air globally.

Martin and Clyburne say long-term exposure to PM2.5 and carbon dioxide emissions is a leading cause of cancer. The inhalation of these emissions can lead to cardiovascular disease, decreased lung function and ultimately, death.

Emissions “are probably the biggest issue we face right now. It could have major implications if we as a society don’t change,” says Clyburne.

PM2.5 are tiny particles that come from fine aerosol emissions, such as smoke from fires, coal burning and agriculture, however it can also occur naturally in the atmosphere. Similarly to PM2.5, Carbon dioxide comes from industrial and energy-related emissions, such as agriculture and vehicle exhaust.

Why should we care?

Martin and Clyburne say every year 31 billion tonnes of carbon dioxide are emitted, which results in six million deaths globally.

Canada alone emits 500 million tons of carbon dioxide every year, which makes up 1.6% of all emissions worldwide. China has the highest rates of carbon dioxide emissions, making up 22.95% of all emissions, according to Statista.

Though Halifax’s air quality levels are not threatening, Martin says they could decline due to an increasing population which would rely on more PM2.5 and carbon dioxide-heavy resources.“There’s no threshold,” Martin says. “We have to act now to make things better before they get worse.”

Air monitoring

There have been strides made in Canada to lower these emissions but Martin and Clyburne say they are inadequate.

In Canada there’s only one air monitoring site every few thousand miles. With the nearest air monitoring site thousands of miles away in Ontario, air quality monitoring in Halifax is at a minimum. Martin says air quality is a global and local issue.

“To the degree we are Canadians, we should care about air quality and monitoring across Canada,” Martin says. He adds Canadians “should care about it to the degree they care about other forms of suffering in the world, to the degree that they care about civil unrest in the world or famine. (It) warrants attention.”

What we can do

Martin and Clyburne suggest taking public transport, bicycling, reducing or stopping car idling, and burning wood to decrease the emissions in Halifax.

They also recommend that people switch to carbon-free or carbon-neutral products such as energy saving cell phones and batteries. Products can be verified as carbon-free or carbon-neutral on

Yet, Clyburne says that “this is a band-aid to give us time, not a solution.” The technologies that are currently being developed to reduce emissions will take years, if not decades, to build and they are by no means a guarantee of improving air quality permanently.

Clyburne stresses that by reducing emissions now, there will be a reduced threat to health in the future.