Traffic-related air pollutants highest near major roads, increases risk to human health

This may not come as a surprise to many people, but the closer you are to a major road, the higher your exposure to air contaminants. In fact, according to a new report from the Metro Vancouver Regional District “multiple traffic-related air pollutants (TRAP) have been identified with adverse health effects. Living and spending time near a major roadway has been identified as a risk factor for a number of respiratory symptoms and cardiovascular problems.”

Approximately half the population of Metro Vancouver lives near a major roadway.

Major roadways have more than 15,000 vehicles per day using them. In Langley, examples include 200th Street, 208th Street, the Langley Bypass, and Fraser Highway.

Traffic-related air pollutants can be elevated up to 250 metres from major roads. Select image to enlarge.

The results of the study show that within 250 metres of a major roadway is where there is a significantly higher concentration of air contaminants.

The following chart shows the increase in air contaminants near major roadways compared to ambient air quality.

Traffic contributed to significant increases of measured air contaminants at the Clark Drive monitoring station, relative to the comparison station in the Metro Vancouver study. Select chart to enlarge.

Over other findings include:

• Large trucks are a main contributor to the amount of air contaminants associated with major roadways
• The highest concentrations were measured when the wind was blowing from a nearby major intersection
• Concentrations near a major roadway can vary considerably from hour to hour and day to day based on traffic volumes and wind

The good news is that air quality has been improving overall in our region, and “these trends are expected to continue, as newer and cleaner vehicles, including electric vehicles, replace existing cars and trucks while use of public transit and active transportation increases.”

Even so, the regional district will be working to further help reduce people’s exposure to traffic-related air pollutants. This work will need to be supported by both the provincial government and municipalities.

For more information, please review Metro Vancouver Near-Road Air Quality Monitoring Study.