British Columbia

Why air pollution apps may be misleading

App that shows the equivalent number of cigarettes you “smoke” a day by simply breathing in polluted air in your local area may not be applicable to wildfire smoke.

An app estimated that people in Vancouver were being exposed to pollution equivalent to 8 cigarettes a day

This picture taken on Aug. 22 shows how smoky the skies were in Vancouver. On a clear day, the buildings and mountains are visible. (Tina Lovgreen/CBC)

For the past several days, air quality has been top of mind for many across B.C., as wildfires burning across the province have made for smoky skies and poor air quality. 

The air quality health risk hit the highest rating in some areas on Monday, reaching a 10+ rating, meaning the health risk is very high and there are high concentrations of fine particulate matter, also known as  PM2.5, in the air.

Many, including radio stations, turned to a mobile app that estimates the effects of current air pollution on people. 

A few days ago, the app estimated that people in Vancouver were breathing in particulate matter akin to smoking eight cigarettes per day. 

But those estimates may be overstated. 

The app leaves the impression that it can compare one form of particulate matter to another, but it doesn't.

It is based on science done by Robert Muller, a University of California-Berkeley physicist in a paper he co-wrote where he estimates 4,400 people die everyday from air pollution

"It's likely that not all PM2.5 is equally dangerous," said Muller. 

He says the science of how dangerous fine particulate matter from forest fires is has not been done.

Amaury Martini created the app a few years ago. He was inspired to build it after living in Beijing. 

"We actually say in our app, it's an estimate," said Martini. 

"We cannot talk about the full equivalent between particulates you inhale with cigarettes and air pollution. The study is based not on particulates themselves but on the health effects," he said. 

He says he's going to rejig it when there's better data, which he said Berkeley University scientists are working on. 

With files from Yvette Brend.


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