Can the air-quality index be trusted? This guy wants to know

Some people believe ambient air quality measurements presented on Environment Ontario's Air Quality Index site are representative of what people at street level are actually breathing.

Environmental Commissioner of Ontario Gord Miller is intent on finding out whether that's true in the province of Ontario.

"What we became aware of and concerned about is that the street-level air quality may be quite different than the Air Quality Index (AQI) levels reported for a community," Miller said yesterday during a media conference in front of the Bondar Pavilion.

The AQI is intended to give an overview of regional air quality, not to give an indication of ground level air quality in localized areas, Miller said.

"That's the issue we're exploring," he said. "Is the Air Quality Index enough or is there something more necessary?"

To find out whether there's a difference between street-level air quality and the official AQI, Miller and his team have been taking sample 'snapshots' in various locations.

"We know that it's clearly an issue but we don't know how widespread it is or how frequently it happens," he said. "That's the question we're trying to answer."

Last year, his team took samples for short time periods in seven cities.

Sault Ste. Marie was one of those cities.

They sampled the air downtown for about three hours one day, very close to where yesterday's media conference was held, and found it exceeded Ministry of the Environment standards for fine particulate matter.

The AQI for that day in the Sault was very good.

"That's one reason we're back again this year," Miller told media and members of the public who gathered to hear what he had to say.

Saultite Dax D'Orazio was one of those people.

He listened intently from behind his air filtering mask, making sure Miller had a good view of his T-shirt that read "Thanks Essar."

Miller told D'Orazio his intent was not to identify sources of pollution in this study, only to see whether there's a difference between air quality measurements at official monitoring stations and in places where people commonly gather or in proximity to industrial locations.

"The intent here is not to chase down one particular industrial emitter or another," Miller said. "It's to try and get that cumulative effect on the street. It's not just one industrial emitter that's involved - it's the busses and the trucks - the diesel emissions and to some extent the car emissions. It's the other kinds of industrial activity we have. We're looking for the collective cumulative effect of what people get exposed to."

But the other reason Miller came to Sault Ste. Marie was because of people like D'Orazio.

"The reason I'm doing this media conference in Sault Ste. Marie and not in Toronto is the level of concern that's developed in this community about air quality generally," said Miller.

He said that after he had begun his review in 2007 he read stories from the media in Sault Ste. Marie that dealt with the issue.

"When I started seeing it in the media up here, I said there's a community that's more engaged in the kind of thing that we're talking about," he said.

During yesterday's news conference, Miller stood in front of a pickup truck with air quality measuring devices active in it.

A monitor located in the back of the truck sampled the air for fine particulate matter while another on top of the cab measured ozone levels.

Miller said these are the two substances indexed by Environment Ontario's AQI.

"Whichever one is worse relative to their own scale, so if ozone is thicker and bad one afternoon for example, then the Air Quality Index will give a warning for ozone," he said. "But if the particulate matter is higher, then that means the warnings on the Air Quality Index would be based on particulate matter."

Ozone damages the lining of the lungs and fine particulate matter penetrates deep into the lungs, he said.

The fine particulate matter, known also as PM 2.5, can be harmful or irritating itself, depending on what it is composed of, or it can carry other harmful or irritating substances into the body through the lungs, he explained.

The surveys Miller and his team are completing this year are more detailed.

They've been to the Sault once before and completed two days of sampling in different locations.

Yesterday was the second day of a two-day trip and Miller said they may return for one more sampling trip before the study is done, if scheduling permits.

The team wwas planning to sample the air in the Bondar Pavilion parking lot for about three hours before moving on to another location, said Miller.

He also said they would make sure data from the West End of Sault Ste. Marie makes it into his review.

Data from the review will be compiled and interpreted then Miller will present a report to the Legislative Assembly, complete with recommendations, in the fall of this year.

"We may make the data available if there is an interest after the report," he said.

Miller is one of only two independent environmental commissioners in the world, he said.

"I report directly to the Legislative Assembly, I am an environmental watchdog," he said. "It is my role, not just to oversee a total of 13 different government ministries with respect to decisions they make about the environment."

Only Miller and his counterpart in New Zealand report directly to the legilsature, he said.