Air pollution in Massachusetts, most of which comes from cars and other vehicles, can be blamed for an estimated 2,780 deaths a year — roughly 5 percent of the total number of deaths in the state. There are other harmful health effects, too, from asthma and low birth weights to lower IQs in children growing up in areas with higher pollution levels. Researchers at Boston College analyzed data from across the state, pinpointing the areas in Massachusetts with the worst pollution.

The study’s lead author, Dr. Philip Landrigan, joined Morning Edition hosts Paris Alston and Jeremy Siegel to discuss the study and what people should do next. This transcript has been lightly edited for clarity.

Jeremy Siegel: When we're talking about air pollution, when you're analyzing air pollution, what specifically are we talking about?

Dr. Philip Landrigan: Specifically, we're talking about invisible airborne particles called PM2.5. That designation stands for particulate matter with a diameter of 2.5 microns. So these are invisible microscopic particles, so small that when a person inhales them, they can go right down into the depths of the lung and some even get into the bloodstream.

Siegel: What does that come from? What's producing those?

Landrigan: Well, two main categories. Two-thirds of it comes from motor vehicles: cars, trucks, buses, trains, airplanes. One-third comes from stationary sources: power plants, factories, home and residential heating.

Paris Alston: We've mentioned that 2,780 people, to be exact, die per year from that air pollution. That's about 5% of the state's deaths each year. And that could be from things like lung cancer, heart disease or stroke that manifest as a result of exposure to that pollution. And you also looked at a slew of other health impacts that this can have, including asthma, pediatric asthma, even IQ loss. Tell us more about those findings.

Landrigan: The reason we were able to connect air pollution to all those many health effects has to do with the fact that over the past 25 or 30 years, there have been a number of high-quality epidemiology studies, led by the famous Harvard Six Cities study, that have connected the dots, that have linked certain levels of air pollution to a certain degree of risk for these various diseases.

So in adults, we looked at heart disease, stroke, lung disease, lung cancer. Beyond that, we looked at the impact that fine particulate air pollution has on childhood asthma. We looked at the impact on pregnancy, measured as the number of low birth weight babies born in Massachusetts. And then finally, the newest part of the whole analysis was looking at the link between air pollution and IQ loss in children.

Siegel: What can we glean from from all of that? How are we seeing these things affect things like IQ?

Landrigan: Well, we learned a long time ago, in studying children exposed to lead, that one of the impacts that lead has on children is that it causes an injury to their brain that shows up as IQ loss as well as various behavioral problems. And one of our coauthors, David Bellinger, and I have worked together before on lead and we said, "Let's look at the emerging data on the link between air pollution and brain function." And that's why we look specifically at the link between air pollution and IQ loss in this study.

Alston: There's an interactive map that is involved with this study, and we can see that Boston is the hardest hit, according to your research. We also have been hearing that there are areas of Boston that deal disproportionately with things like extreme heat, for instance. Do we see some of those same trends when it comes to air pollution?

Landrigan: Our study was not as fine grained as some other studies, but there have been a number of studies done in Massachusetts, and indeed across the United States, that show very clearly that air pollution is not evenly distributed. That is to say it's most heavily concentrated in low-income communities, communities of color, inner-city communities and communities along highways.

But having said that, it's also important I emphasize that air pollution is everywhere. Yes, it may be most highly concentrated in some inner-city communities, but no city or town in Massachusetts is spared the health impacts of air pollution. Even the greenest, wealthiest suburbs are suffering premature deaths, childhood asthma and IQ loss in kids as the consequence of air pollution. Air pollution does not respect political boundaries. It's everybody's problem, which is why we need collective solutions to the issue.

"Air pollution is everywhere. Yes, it may be most highly concentrated in some inner-city communities, but no city or town in Massachusetts is spared the health impacts of air pollution."
-Dr. Philip Landrigan, Boston College

Siegel: Can you put this all into context a little bit for us? I was in Los Angeles recently where every morning you wake up and you can see the layer of smog over the entire city. Obviously, that's not something we really see here in Boston. How does Massachusetts stack up against other states when it comes to all of this with air pollution?

Landrigan: Let me answer that in two ways: Historically and at the present time. Historically, we're way better, all across the United States, including Massachusetts, than we used to be. Since we passed the Clean Air Act in 1970, signed into law by President Richard Nixon, we have reduced air pollution emissions in the U.S. by 74%.

That's just an astounding success story. We've also basically eliminated airborne lead poisoning when we took out of gasoline in the late 1970s and early '80s. So we have made a lot of progress, but clearly we still have a problem of 2,780 deaths — it's way too many, roughly 5% of all deaths in Massachusetts.

Here in Massachusetts, we are better off than L.A. We are better off certainly than the industrialized states in the Midwest and the upper South, which is good. But we still have a problem. And moreover, some of the pollution that's generated down there in places like the Ohio Valley tracks up into the northeast on the prevailing winds. And we're downwind from those places. And so we get their pollution, in addition to the 938,000 tons of pollution that we generate each year right here in Massachusetts.

Alston: There's a list of recommendations on the website that's included with your study. Of those, what would you consider the most urgent, the thing that you would like to see us do today to try to combat this?

Landrigan: I think collectively, we have to recognize that more than 95% of the pollution in Massachusetts comes from the burning of fossil fuels. So then the question is, how can we reduce the burning of fossil fuels?

And pretty much all the recommendations we made speak to that: More solar panels, stopping gas hookups in new construction, stopping the build out of pipelines, shutting down unnecessary compressor stations, like the North Weymouth compressor station. And setting targets and timetables for decarbonizing the state, reducing the number of gas- and diesel-burning vehicles on the road, build out the T, build out high-speed rail.

There's a whole suite of common-sense measures. And by the way, those measures are highly cost effective. Every dollar we have spent since 1970 in fighting air pollution has yielded a $30 return in terms of health and economic benefit. So I think it's time to do it and not wait around.