Air pollution can easily cross any boundary, but the United States and Canada address this through an agreement between the countries and each country’s own regulations.

by Lily Burris

What is air pollution?

Air pollution is, simply, things that are in the air that aren’t wanted, says Sebastian Eastham, a research scientist at the Massachusetts Institute of Technology.

“Usually, we’ll refer to things like air quality cause it kind of points out more of a metric that you can talk about and how air quality has been degraded by anthropogenic or human activity,” Eastham says.

Air quality is measured with a variety of tools to determine how many harmful pollutants can be found in a given sample, putting focus on how human emissions cause air pollution.

Eastham says who is downwind of whom, what the temperature is, the amount of precipitation an area has and what is being put into the air can affect what exactly the air pollution is in an area.

How is it managed between the two countries?

The United States and Canada signed the Air Quality Agreement in 1991, addressing acid rain related pollution, and it was expanded in 2000 to address ozone emissions and smog issues. Ambient air quality standards in both nations set the acceptable or manageable amount of prominent pollutants allowed in the air.

The National Ambient Air Quality Standards in the United States monitor carbon monoxide, lead, nitrogen dioxide, ozone, particle pollution and sulfur dioxide.  The Canadian Ambient Air Quality Standards monitor fine particulate matter, ozone, sulphur dioxide and nitrogen dioxide. 

Concerns are raised on both sides of the border on whether these agreements are enough to provide clean air for citizens. Figures show air pollution emissions are decreasing, but people are still at risk. In the United States alone, about 45% of the population live in an area with unhealthy ozone or particle pollution levels.

What is the impact of air pollution?

Air quality is of significant concern to countries, as poor air quality can lead to health implications and premature death. 

“The really simple explanation is that particulate matter in particular, if it’s large and has a diameter of more than 2.5 microns, it’s less likely to harm you, it can’t penetrate deep into the lungs,” says Eastham. “Particulate matter that has less than 2.5 microns diameter is more likely to penetrate deep into the lungs, and we correlate that successfully with greater mortality outcomes, and this is one of the things that’s been done over and over again.”

Many studies show a correlation between poor air quality and premature death, specifically relating to particulate matter and premature death.

“All around the mortality rate has increased by tens or hundreds of thousands a year every year because of pollution,” says Eastham. “So at some level, it’s best to sort of take a broad look and say anything we can do to bring that down is good.”