A new study by Harvard University researchers suggests air pollution may be killing elderly Utahns — even when the air is relatively clean.

Even short-term exposure to small amounts of particulate pollution — the kind associated with Utah’s seasonal inversions — caused a noticeable increase in the number of deaths among Americans age 65 and older, according to the study released late last month.

The Harvard study, published Dec. 26 in the Journal of the American Medical Association, is the latest of several recent papers that area physicians are heralding as proof the state needs to get tough on air pollution.

“We need to be absolutely relentless in trying to control emissions and improve our air quality all through the year, not just on the days that get everybody’s attention,” said Robert Paine, a University of Utah Hospital pulmonologist who also sits on the board of the advocacy group Utah Physicians for a Healthy Environment.

Particulates regularly accumulate above the Wasatch Front to levels far surpassing those considered safe by the U.S. Environmental Protection Agency. And while most Utahns understand that these so-called orange or red air-quality days can be damaging to their health, the Harvard study found that much smaller amounts of pollution — even those present on what Utahns would consider a green air-quality day — are associated with a higher risks of death among the elderly.

“It’s not only when you have a high level of particulate matter that you have to worry about, but also when the particulate matter is low,” said Francesca Dominici, director of the Harvard Data Science Initiative and one of the authors on the study.

Particulate matter, especially fine particulate matter often referred to as PM2.5, is so small that tiny motes travel deep into the lungs, where they cause irritation and trigger respiratory conditions. Recent science suggests these particles may be able to enter the bloodstream and travel through the body, where they may cause a range of problems — including heart attack, stroke, and perhaps even decreased brain function.

Studies specific to Utah have also found that particulate pollution contributes to a host of medical conditions on the Wasatch Front.

In a recent partnership between Brigham Young University in Provo and the Intermountain Medical Center Heart Institute in Salt Lake City, researchers found that particulate matter caused the risk of heart attack to increase sharply among patients with pre-existing heart disease, resulting in periodic influxes of patients at Intermountain Medical Center and LDS Hospital.

Patients were 16 percent more likely to suffer a heart attack or chest pain following exposure to high levels of particulate pollution, said Benjamin Horne, a clinical epidemiologist with Intermountain Healthcare and the lead author on that study. Those with A, B or AB blood types — the majority of the population — were 25 percent more likely to experience a heart attack.

It’s likely that a combination of pollution, pre-existing health conditions and genetics contributes to those elevated risks, said Paine.

“It’s not a single big factor,” the U. physician said. “It’s multiple factors acting together that end up taking a life.”

Paine also co-authored another recent study, based on data from both U. Health and Intermountain Healthcare that found particulate pollution sends an average of 200 Utahns to the hospital with severe pneumonia each year. And when particulate pollution exceeds 40 micrograms per cubic meter of air, older patients were three times as likely to die as a result of developing pneumonia, according to the study.

Taken together, Paine said, recent research suggests Utah’s leaders and residents should abandon complacency on air quality.

“Utah needs to do more about air pollution,” he said, comparing residents’ attitudes about pollution to previous generations’ feelings about seat belts in automobiles.

“We need to change the culture in Utah so people think about air quality and make efforts to improve air quality day in and day out,” Paine said, “just as they wouldn’t drive without a seat belt.”

Dominici, the Harvard researcher, said that air quality tends to have the greatest effects on disadvantaged populations, and she criticized federal air quality standards for failing to protect vulnerable Americans.

“The safety standards that the EPA has been setting are not safe enough,” she said, arguing that elected officials need to push for the outright elimination of particulate pollution. “We have not been able to find evidence of a safe level.”

To some extent, Utahns can lessen the impact pollution can have on their health. Residents should stay indoors when the air is polluted, Paine said, and keep their windows closed. Furnace filters should be changed regularly, he said, and drivers should use the “recirculate” feature on their vehicle heaters.

Horne, the Intermountain Healthcare epidemiologist, added that maintaining good health is also important, as pollution often acts as a trigger of severe complications among those with existing conditions such as asthma, heart disease or diabetes. He suggested eating a balanced diet and getting adequate exercise — indoors, where the air is generally cleaner.

But unlike health problems such as smoking or an unhealthy diet, the challenge of air pollution, Dominici added, is that the average person has little ability to reduce their exposure.

“Everyone has to breathe,” she said. “You can’t choose whether or not to breathe.”