I was talking today with a long-time Pittsburgher, when, as is often the case lately, the subject of air quality came up.

“It’s really good here now,” she said. “ . . . Isn’t it?”

It is, like many things, a matter of perspective.

If you have lived in Pittsburgh for more than, say, 20 years, you will be aware of a distinct change in the air. And it is, in many ways much improved; it certainly looks clearer. And who, after all, would not celebrate the fact that we can no longer see the air we breathe? Yet the fact remains that our air, the stuff we inhale every living moment, is not doing us as much good as we think.

We have become accustomed of late to find ourselves at the summit of some list or other: Pittsburgh, most livable city; the best city for foodies; the city with the best ballpark in America, and one of the best views, to boot; Pittsburgh, the top family destination. It might feel like it has been a long road, but we have finally arrived. So it might come as a disappointment to learn that when it comes to air quality, we still rank in the bottom 10 percent nationally. Asthma rates are among the highest in the nation. Cancer rates are not much to be proud of either.

It turns out that while changes in the sources of pollution mean that the air here looks so much better than it used to, we are constantly inhaling minute particles of noxious, toxic chemicals: invisible, highly invasive, downright dangerous. Traveling deep into our lungs, they can wreak havoc on our respiratory systems, our cardiovascular function, with the very ability of our immune systems to protect us.

The causes of this pollution are many and varied. Some, we can do little about: we sit in a steep river valley where air doesn’t circulate as much as it just collects. On a bad day, when conditions are just right (the technical term is an inversion), all of the bad stuff we produce just sits in the valley, going nowhere, except maybe our lungs.

And our topography isn’t changing any time soon. But we do make much of our own airborne misery. Point source polluters are the most obvious culprits – coke works, steel mills, power plants burning fossil fuels – but diesel emissions – trucks, boats, rail traffic – pose a major health risk too, as does burning wood, something we do here with abandon, it turns out. And much more besides.

The reason the subject crops up so often is that recently I have been involved in a project, In the Air: Visualizing What We Breathe, on view at Pittsburgh Filmmakers through February 26th. Featuring the work of photographers Scott Goldsmith, Lynn Johnson, Annie O’Neill and myself, environmental journalist Reid Frazier, designer Brett Yasko and curator Laura Domencic, of the Pittsburgh Center for the Arts, In the Air offers audiences the opportunity to consider where we stand in terms of air quality: better than we were when the steel mills were going at full tilt, definitely; yet, sadly, still worse than just about every comparable city in the United States.

In the Air is not a screed, nor is it merely finger-pointing. It does offer an opportunity for us to consider the quality of the air we breathe, and to have a civil conversation about how we might improve. In terms of air quality, we can choose to look at it in terms of where we once were, or to think about where we are now.

So perhaps it is all a question of perspective. But surely air quality is one list it is critical to top?

In the following photo slide show:

Annie O’Neill photographed survivors of the Donora inversion of 1948 in which 17 people died as a result of fumes form the local zinc plant becoming trapped over the town.

Brian Cohen photographed some of the major point source and transport-related polluters of the region.

Lynn Johnson photographed the communities of Cheswick/Springdale, living in the shadow of the coal-fired power plant.

Scott Goldsmith photographed people and their responses to air quality issues in the region, as well as some of the major point-source polluters.

Brian Cohen is a freelance photographer living and working in Pittsburgh. Originally from London, England, he loves to take pictures of his adopted city and its people.