Clearing the Air - Y Magazine
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Clearing the Air

We can all breathe a little easier thanks to two decades of research by BYU’s Arden Pope.

We can all breathe a little easier thanks to two decades of research by BYU’s Arden Pope.

Clearing the Air

He has been called a long-haired environmentalist, a Harvard liberal, a cheater, and—most threatening to a serious scientist like him—dead wrong. Companies have spent millions trying to discredit him, and he has been enshrined in the “Hall of Shame.”

Despite this barrage, in 20 years the research of C. Arden Pope III (BS ’78) has garnered the support of nearly every expert in his field. His once-controversial findings became the basis for U.S. federal regulations and a Supreme Court decision that save tens of thousands of lives annually. But the person in the BYU community with the biggest right to shout to the world, “I told you so!” is probably the least likely to do so.

Pope would rather invest his energy in his ongoing research program—in which he is at the vanguard of a new line of research that examines air pollution’s health effects on the heart. In December he was the lead author on a study published in the leading cardiology journal Circulation that linked air pollution to an increased risk for heart attacks.

Despite how far the once-embattled scientist has come, Pope insists he is still the same person he was before the discovery that started it all 19 years ago—before the sabbatical at Harvard, the controversies, the lawsuits, the awards, and what Science magazine called “the biggest environmental fight of the [1990s].” This year’s Karl G. Maeser Distinguished Faculty Lecturer, Pope may not have changed through it all, but he has changed the world. If you want to know how, open your front door and take a d-e-e-p breath.

Where There’s Smoke

None of it may have happened if a BYU student hadn’t flaked on him. In 1988 Pope was in his fourth year in the now-defunct Agricultural Economics Department. A natural-resource and environmental economist, he regularly used complex statistical and economic tools to measure the dollar value of wilderness, air quality, and other environmental amenities.

That year a student asked him what she should write her term paper about. He referred her to a newspaper article about Geneva Steel, the steel mill five miles northwest of BYU that was back online after a yearlong strike. “Someone was arguing that ‘Little Johnny, my son, was sick when the mill was operating; he got better when the mill closed down and got sick again when the mill started operating again and the air got bad,’” he recalls. The professor wondered about these casually observed correlations.

Pope helped the student obtain records of children admitted to the local hospital for respiratory problems over the three years in question. Then she promptly dropped the class. The stack of records sat on Pope’s desk until curiosity got the best of him and he entered the data by hand into his computer to analyze.

PollutionPope was startled by the results—during the winter when the mill was closed, pediatric respiratory admissions were less than half of those in a typical winter. He quietly submitted his findings to the American Journal of Public Health. Pope wasn’t naïve about the potential for controversy with the study, but he could not have anticipated the fervor of the reactions—favorable and critical—that it would stir up.

To those who had spent their careers researching the health effects of air pollution, Pope’s novel study came like a bolt of lightning out of a dirty blue sky. “I’d been heavily involved in air-pollution research for a long time, and particles did not hit our radar screen until [Pope’s Geneva Steel paper] came out,” says Robert Devlin, chief of the clinical-research branch at the EPA. “I mean, no one even thought about them.”

At the time, scientists and regulators were mostly focused on gases like ozone. Pope’s study examined the impact of separate pollutants that researchers and regulators were largely ignoring—“particulate matter”—microscopic stuff produced during combustion in car engines, power plants, and steel mills that floats in the air.

“Genius to me is when you see something, and it’s so obvious you say, ‘Oh, I should have thought of that myself,’” says Douglas Dockery, professor of environmental epidemiology at the Harvard School of Public Health. “What Arden did was one of those genius moments to all of us.” Dockery says the genius lay in Pope’s “clever” study design. “The steel-mill paper was just such an elegant study. [It was] what we always wanted to do—go in and turn off air pollution and turn it back on,” he says.

That’s one of the rare compliments Pope will accept, because he loves a clever study design. Along with Pope’s more typical interests—coaching his sons’ soccer teams, going on long hikes with the family, and reading biographies—he finds particular delight in divining ways to analyze vast quantities of numbers.

“Our mealtime centers around different conversations than most people’s mealtimes do,” chuckles his wife, Ronda Gneiting Pope (BS ’77), whose two oldest sons have parlayed this “home schooling” into PhDs in economics. “I feel a little bit out of the loop sometimes.”

Get Pope going on study designs, and you had better be ready to hear about plotting variables, sensitivity analyses, and confidence intervals that result from stratification. Ever the perceptive teacher, however, he’ll catch himself when eyes glaze over.

“Most people don’t care about this stuff,” he says. Others’ indifference, however, doesn’t hamper his enthusiasm. “If you want to get me excited, let me talk about study design.”

A Public Outcry

In the late 1980s Geneva Steel was one of Utah County’s largest employers, and Pope expected some opposition to a study that painted the company in a negative light. But he wasn’t going after the mill—he was interested in the health effects of air pollution; the steel mill just happened to be its biggest local source. On the other hand, Geneva Steel officials worried there would be a knee-jerk reaction from regulators before all questions about health effects were answered.

In newspaper articles about the study, Geneva officials emphasized that the valley’s air met federal standards for 355 days of the year and that the study made no direct link to emissions from the steel mill. Letters to the editor from residents defending the company piled up in BYU’s public-relations office: “I personally believe that Pope’s attack on Geneva was brought about by a sole desire for fame and glory” and “Is he practicing bad science? Or is it possible that he is so biased and prejudiced that he can’t produce an accurate and honest report?”

The Geneva Steel controversy peaked one evening when Pope returned home from a long run and Ronda, upset by a new article casting doubt on his work, threw the newspaper in front of him. The company had hired epidemiologist Steven Lamm of Georgetown’s School of Medicine to review Pope’s study. Lamm asserted that the increase in hospital admissions Pope highlighted was caused by an outbreak of a respiratory virus. He called the decline in hospital admissions the year the mill closed a “historical accident” and claimed that Pope’s work “suffer[ed] from ecological fallacy.”

Pope received a crush of media calls and reluctantly set up a press conference—his first and last—so that he could answer the questions and get back to his research. Referring only to his studies that had been previously peer reviewed and published, he explained why he thought Lamm’s conclusions were inaccurate. That didn’t completely settle the issue, but the calls subsided.

When criticisms arise, Pope prefers to let his published studies speak for themselves. “As long as we keep publishing good peer-reviewed research and answer the questions that legitimately come up, that is the best response to criticism,” he says. “I believe that as much as I believe anything academically. Never take criticism personally—just move on.”

Is it really that easy for him? Ronda nods. “He has always had that ability to not be offended, even when people are trying to offend him.”

Pope’s approach through the years has been to reach out to his critics and incorporate their questions into his next studies. One he respects most, Robert Phalen, a professor of community and environmental medicine at UC–Irvine, returns the esteem. “Arden actively seeks feedback and criticism and doesn’t punish people for criticism,” says Phalen, whose quarrel is not with Pope’s research, but with the implications others draw from it. “Arden welcomes it more than anyone I’ve known.”

The Geneva Steel paper lent Pope a measure of fame within environmental circles. “When I saw that article, I knew he was somebody I would like to collaborate with,” says Harvard’s Dockery.

So when Dockery heard about the scrutiny Pope was facing, he had an idea. He offered to send Pope some used devices that could measure Utah Valley children’s lung function before, during, and after pollution episodes. That kicked off a string of papers Pope published in health and medical journals during the early ’90s, often with Dockery’s collaboration and always with his advice. Their research showed air pollution’s impact on various outcomes beyond just monthly hospital admissions. Using statistical approaches, they matched daily fluctuations in particle levels with daily fluctuations in respiratory symptoms, school absences, and even deaths. Dockery performed similar studies with Harvard colleague Joel Schwartz, who would also become one of Pope’s collaborators.

“Particles became an issue because people like Arden, Doug Dockery, and Joel Schwartz started publishing these papers that suggested that exposure to very low concentrations of particles, like those found in pretty much every U.S. city, was actually killing people,” says the EPA’s Devlin. “That was really an earth-shattering idea, because in the previous 40 years of studying air pollution, no one had suggested that air pollutants actually killed people like that.”

At the time an EPA rule regulated the amount of “coarse” particles in the air smaller than 10 microns, or 10 millionths of a meter. That may sound small, but in the world of particles, it’s actually relatively large. It refers primarily to things like dust from dirt roads and gravel-crushing operations. These new studies focused attention on “fine” particles smaller than 2.5 microns that scientists now know lodge deep within human lung tissue.

The new papers silenced legitimate critics of the Geneva Steel paper and established Pope’s credibility as a researcher. (Pope credits Geneva for spending millions to substantially limit pollution in the years before the mill permanently closed for unrelated reasons in 2002.) They also resulted in an invitation from Dockery for Pope to be a visiting scientist at the Harvard School of Public Health in 1992. As the Popes headed to Boston with the controversy behind them, they didn’t know they were driving toward a much larger one.

A Deadly Finding

Until this point Pope and his collaborators had studied short-term health effects from particle pollution. Their basic finding: air gets dirtier one day, more people die the next. But no one knew the long-term effects of breathing polluted air. Would a person who lived her entire life in Los Angeles be at greater risk than someone reared in rural Iowa?

To answer that question, a researcher would need a difficult-to-obtain set of data: air-pollution readings collected from places with diverse levels of pollution over a long period of time and information about the health, traits, and behavior of a huge sample of people living in those areas over the same period. Fortuitously, that is exactly what the Harvard researchers had been gathering for 15 years in a study of 8,000 people in six eastern cities.

When Pope applied his econometric tools to the mountain of data, he found such a strong effect from air pollution that the team worried they had done something wrong. Adjusted mortality rates were strongly associated with particle pollution. For example, rates for Steubenville, Ohio, the most polluted city in the study, were 26 percent higher than those for Portage, Wisc., the least polluted city.

“After several weeks, I had pretty much analyzed it to death,” Pope recalls. “We were still scared of the results. These effects would not go away.”

Since there was no known reason for this effect, lab director Frank Speizer felt it necessary to verify or reproduce the results in another population before publishing the results.

But they didn’t want to wait another 15 years to track a new set of people. So Speizer referred Pope to the American Cancer Society (ACS), which had been tracking 1.2 million people for seven years to determine causes of cancer.

Pope waded through the ACS data and matched about 500,000 of the people up with air pollution and weather measurements for their locales. After factoring out everything they could think of—occupation, smoking, obesity—Pope and his colleagues still found that people in the most polluted cities had a 17 percent higher mortality rate than people in the least polluted cities.

Clearing the AirSpeizer gave the go-ahead to submit both studies for review. What is now known as the “Harvard Six Cities Study” was published in 1993 in the New England Journal of Medicine, with Dockery as the lead author; the “Pope ACS Study” was published in the American Journal of Critical Care Medicine in 1995. Along with a follow-up study Pope published in the Journal of the American Medical Association in 2002, these studies remain the most frequently cited in air-pollution research.

By comparing the mortality rates in different cities with varying levels of pollution, the researchers documented how many more people die with every unit increase in pollution, even when it was below the legal limits. Such information was vital to policy makers charged with protecting the public.

“That study became the core of what we started to use back then to evaluate the benefits [of reducing particulate matter],” says John Bachmann, who recently retired as associate director for science/policy at the EPA’s Office of Air Quality Planning and Standards Organization. “Including the updates Arden’s done on it, his is still the number one study used in the world by anybody who assesses the health effects of reducing particulate matter.”

Bachmann and his EPA colleagues were already considering a new set of rules to control “fine” particles for the first time, based largely on Pope, Dockery, and Schwartz’s earlier short-term studies. The new long-term studies only strengthened the argument for clamping down on polluters.

When big business interests realized that the proposed controls would cost them between $2.5 and $7 billion, they mounted a campaign to discredit the linchpin studies—and their authors. The American Iron and Steel Institute hired a researcher who shortly announced he could not reproduce the studies’ results. A coalition of 500 industry groups joined forces to lobby against the new rules and called the science supporting them “totally inadequate.”

“Critics tried to characterize me as one of two things—either an incompetent ag-economist with a vendetta against them or as some wacked-out eastern elite environmentalist trying to say the sky was falling,” Pope says. “And the minute I would talk, they would know that wasn’t true. As much as I would like to have a more polished demeanor, I have this muddy southern-Idaho accent. The truth is, growing up on a farm, I didn’t know the word environmentalist ever stood on its own. I only heard ‘darned’ environmentalist.”

Integrity on the Line

In 1997 the EPA sided with the scientists and established the new standards. The rules were immediately challenged in a lawsuit filed by the American Trucking Association, the U.S. Chamber of Commerce, and other business groups.

In an effort to settle the dispute, Congress asked that the Six Cities and Pope ACS Studies be reviewed by the Health Effects Institute, a nonprofit think tank funded jointly by the EPA and industry groups. It was the closest thing to an impartial observer in the back-and-forth tussle over air-pollution science. A team of respected air-pollution researchers from various universities carefully scrutinized the data, looking for errors in the original studies and seeking to reproduce their findings.

Understandably, Dockery was worried.

“It was a very, very difficult thing to say, ‘Okay here’s my baby, you take it and examine it, and you decide whether this is all real or not,’” he says. “We just had to sit around and wait for them to come back with an answer. There was a lot of anxiety there.”

Even the normally unflappable Pope was nervous.

“We knew we hadn’t cheated and had tried to do the best job we could, but we were certainly hoping they would come up with the same results,” he recalls. “I was far more anxious about this process than anything that ever appeared in any newspaper. This mattered to me. My integrity as a scientist really mattered.”

In 1999, with the new EPA standards still tangled in litigation, the Health Effects Institute was set to announce its preliminary results at a press conference in Washington, D.C. Pope and Dockery remember the feeling of anticipation in the room.

“People were anxious to hear—did these folks really cheat? Or just do garbage science?” says Pope, who sat with his friends and “codefendants” Dockery and Schwartz, along with Speizer and other colleagues.

The verdict? The Health Effects Institute announced that the data were sound and that its review team had replicated Pope and Dockery’s original findings.

“I just wanted to jump up and down and cheer,” Dockery says. “I wanted to go out and have a beer; of course, Arden wanted juice.”

A Breath of Fresh Air

In 2001 the U.S. Supreme Court ruled in favor of the EPA, and the new standards went into effect.

“Arden was a critical figure in proving the old standards were not tough enough to protect public health,” says the EPA’s Bachmann. “Tens of thousands of lives are being prolonged each year as a result of regulations that either stemmed directly or indirectly from that new standard.”

The impact of the now-vindicated ACS study and the updates Pope has published on it has continued to grow.

“Every major EPA rule since 1997 that has attempted to reduce emissions has relied on the American Cancer Society Study as the basis for estimating the numbers of deaths avoided and ultimately the economic benefits of the rule,” explains Dan Greenbaum, president of the Health Effects Institute. “Arden’s work on the ACS study has, more than any other single study on air pollution and health in the last decade, resulted in what will be substantial improvements on public health for many generations to come.”

With the combative regulatory issues behind him, Pope avoided further political tussles. During the widespread media coverage that followed the 2002 publication of Pope’s update to the ACS study, the chief of staff to California Senator Barbara Boxer contacted BYU. The senator, a member of the Committee on Environmental and Public Works, wanted Pope to testify about his findings later in the week. When the invitation was relayed to Pope over the phone, he paused while checking his schedule. “Can’t. My son’s got a soccer game. Have I told you about him? He’s really improved his foot skills this year. . . ”


When talking about Pope the person, rather than Pope the scientist, it seems his fellow air-pollution experts are reading from the same script: “He’s very modest and self-effacing,” Devlin and Dockery say separately—and verbatim.

Bachmann adds, “He doesn’t come off as, we’ll just say, a Harvard type, as a know-it-all, but as a searcher who doesn’t know everything, who wants to learn from everybody.”

And no matter how much he’s pushed, Pope still won’t gloat in seeing his critics proven wrong by so many respected third parties.

“If you didn’t take it personally in the first place, you never feel like there is a need to feel vindicated,” he says.

Ronda prods him: “You do feel good, though, because people just accept now that air pollution does cause disease, and that was a new way of thinking back in the ’80s.”

Indeed they do. Five years ago, at the meetings of the International Society for Environmental Epidemiology near Munich, Pope had just finished giving a speech. As he was walking past researchers displaying the results of their studies on easels, someone tapped him on the shoulder, addressed him by name, and started talking to him. Pope thought the person looked vaguely familiar. It was epidemiologist Steven Lamm.

“We visited politely,” Pope recalls. “Of course I didn’t say ‘I told you so’ or anything. There is no reason to say that. We had a very pleasant conversation. He showed me a poster that he had there. I looked at it. Then I left.”

Michael Smart is a media relations manager for BYU University Communications.

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