Dr. Dan Crouse is a researcher with the department of sociology at the University of New Brunswick. Crouse also works as a researcher with the New Brunswick Institute for Research, Data and Training, which operates in partnership with Statistics Canada.
“I am a Health Geographer, so I have been interested in studying links between where people live and their risks to health for almost 20 years,” said Crouse.
Crouse is currently playing a lead role in Canada’s largest ever study examining the links between air pollution and risk of mortality. Crouse and 15 other Canadian researchers across the country are working on the project.
The study, titled “Mortality – Air Pollution Associations in Low-Exposure Environments (MAPLE): Phase 1” evaluates the relationship between long-term exposure to low concentrations of air pollution and non-accidental mortality.
“We need a fairly big team of people contributing to different kinds of expertise, related to atmospheric modelling of the pollutants, epidemiologists, statisticians, and those with training in methods of estimating long-term exposures to pollution,” said Crouse.
The study followed almost nine million Canadians from across the country for 25 years. The research group used varying methods of measuring pollution, including small buffers around the participant’s home, buffers covering neighbourhoods, and by looking at exposures in the recent short-term versus exposures averaged over eight years.
The results from the study, published in Health Effects Institutes, showed that there are low levels of pollution seen across almost all of Canada, including the Atlantic provinces, which produces small but significant increased risks of dying.
According to Crouse, up until this study, air pollution research was lacking in smaller, less populated cities.
“In the past year, most air pollution research has been based in large cities or heavily polluted areas, and so we had limited knowledge of the potential effects on health in areas with low levels of exposure,” said Crouse.
A shocking finding from the current study reveals an observed increase in risk of dying in all explored areas of the country, even in areas with very low exposures to concentrations of pollution.
“I would say that the most surprising finding is that we did find elevated risks of mortality at concentrations as low as only a few micrograms per cubic meter,” said Crouse.
The study found a five per cent increase in risk of dying when comparing high and low pollution areas. This is a concerning finding, as millions of Canadians are currently living in high polluted regions.
According to the researchers of the study, air pollution is the fourth highest risk factor for death globally and the leading environmental risk factor for disease.
Crouse and his colleagues are hoping their findings will contribute to the push for a reduction in air pollution.
“The results have been presented to Health Canada and to the Environmental Protection Agency (EPA) in the US, and so they should contribute to setting national standards for exposures in Canada, and internationally,” said Crouse.
The research group is now conducting a follow-up analysis to explore the relationship between air pollution and specific causes of death, as well as to evaluate whether moving from an area of high polluted to low polluted air would reduce the risk of dying.