People who live less than 50 metres from a major road or less than 150 metres from a highway are at a higher risk of developing dementia or Parkinson’s disease, according to new research from UBC.
Researchers looked at 678,000 adults living in Metro Vancouver between 1994 and 1998, and then followed up with them once again from 1999 to 2003. They used postal code information to assess each person’s closeness to the road and their exposure to air pollution, noise and green spaces. They ended up identifying 13,170 cases of dementia, 4,210 cases of Parkinson’s disease, 1,277 cases of Alzheimer’s, and 658 cases of Multiple Sclerosis (MS). Researchers classified the different categories of roads based on the traffic volume and the width of the lanes.
The study’s lead author and UBC PhD candidate Weiran Yuchi told CTV News Vancouver the research found living near a major traffic route increased the risk of dementia by 14 per cent, and increased the risk of Parkinson’s by seven per cent.
“We believe that the air pollution associated with traffic actually contributes to the onset of these neurological disorders,” she said.
Due to the relatively low number of Alzheimer’s and MS cases identified, researchers were not able to link an increased risk of those diseases to air pollution, specifically. They are now studying information from across the country to try and get a better understanding of any potential connection.
There was one thing researchers found could mitigate the effects of air pollution: living within 100 metres of a green space.
“There could be several reasons,” Yuchi said. “We believe that maybe the visual presentation … actually is one possible reason. Or, you know, people who live near green space, they’re more physically active, and they pay more attention to their health, and as a result they are at less risk of developing certain neurological disorders.”
Increasing access to parks is one of the goals the City of Vancouver set in its “Greenest City Action Plan,” but according to the Park Board, it hasn’t quite hit its stated target of having everyone within a five-minute walk of a green space by this year.
Senior environment and sustainability planner Chad Townsend said in an email to CTV News Vancouver: “99 per cent of people are within a 10-minute walk of a park or green space (80% are within a five-minute walk). However, distribution is uneven and some neighbourhoods are underserved.”
He singled out Grandview-Woodland and Fairview as areas which have less park land per 1,000 residents, comparatively.
Another goal was to plant 150,000 more trees between 2010 and 2020. Townsend said the Park Board expects to achieve that goal by the end of this year.
Yuchi said in light of Canada’s aging population, the study’s authors are hoping that city planners will take their findings to heart and find ways to increase access to green spaces while reducing traffic.
“The number of cases of neurological disorders are forecast to increase dramatically,” Yuchi said. “Neurological disorders (are) actually one of (the) leading causes of death and disability globally, and we know little about the risk factors of neurological disorders, so therefore we think that it’s necessary for people to pay more attention to neurological health.”