Choked: Life and Breath in the Age of Air Pollution

By Beth Gardiner

“[An] arresting account of one of the biggest environmental threats to human health.” —Scientific American

Air pollution prematurely kills seven million people every year, including more than one hundred thousand Americans. It is strongly linked to strokes, heart attacks, many kinds of cancer, dementia, and premature birth, among other ailments. In Choked, Beth Gardiner travels the world to tell the story of this modern-day plague, taking readers from the halls of power in Washington and the diesel-fogged London streets to Poland’s coal heartland and India’s gasping capital. In a gripping narrative, she exposes the political decisions and economic forces that have kept so many of us breathing dirty air. This is a moving, up-close look at the human toll, where we meet the scientists who have transformed our understanding of pollution’s effects on the body and the ordinary people fighting for a cleaner future.

“A compelling book about a critical subject.” —Elizabeth Kolbert, Pulitzer Prize–winning author of The Sixth Extinction

“Illuminates some disturbing realities, but it also gives us hope by showing us what we can do to clean our air. . . . An urgent, essential read.” —Arnold Schwarzenegger

“Moving . . . By putting a human face on a problem of environmental chemistry, Gardiner shows us the devastation up close, creating a sense of dismay but also urgency to improve lives.” —Washington Post

“Timely, eloquent, and disturbing.” —Nature

“You couldn’t ask for a better guide for nonspecialists and concerned citizens.” —Guardian, Best Book of the Year

“Remarkable.” —Science

“Brilliantly reported and beautifully written.” —Anna Clark, author of The Poisoned City

• Language: English
• Publisher: Open Road Integrated Media
• Release date: Apr 19, 2019
• ISBN: 9780226630793

Beth Gardiner

Beth Gardiner is an environmental journalist who has written for the New York Times, the Guardian, National Geographic, Smithsonian, and Time, among other publications. She is a former Associated Press writer. Both the Pulitzer Center on Crisis Reporting and the Society of Environmental Journalists have awarded her grants to support her work. Gardiner is American but has lived and worked in badly polluted London since 2000.

Book preview

Choked

Choked

Life and Breath in the Age of Air Pollution

Beth Gardiner

The University of Chicago Press

Chicago

The University of Chicago Press, Chicago 60637

© 2019 by Beth Gardiner

All rights reserved. No part of this book may be used or reproduced in any manner whatsoever without written permission, except in the case of brief quotations in critical articles and reviews. For more information, contact the University of Chicago Press, 1427 E. 60th St., Chicago, IL 60637.

Published 2019

Printed in the United States of America

28 27 26 25 24 23 22 21 20 19    1 2 3 4 5

ISBN-13: 978-0-226-49585-9 (cloth)

ISBN-13: 978-0-226-63079-3 (e-book)

DOI: https://doi.org/10.7208/chicago/9780226630793.001.0001

Library of Congress Cataloging-in-Publication Data

Names: Gardiner, Beth, author.

Title: Choked: life and breath in the age of air pollution / Beth Gardiner.

Description: Chicago: The University of Chicago Press, 2019. | Includes bibliographical references and index.

Identifiers: LCCN 2018052335 | ISBN 9780226495859 (cloth: alk. paper) | ISBN 9780226630793 (e-book)

Subjects: LCSH: Air—Pollution. | Air—Pollution—Social aspects. | Air—Pollution—Health aspects. | Environmental quality.

Classification: LCC TD883.1 .G37 2019 | DDC 615.9/02—dc23

LC record available at https://lccn.loc.gov/2018052335

This paper meets the requirements of ANSI/NISO Z39.48-1992 (Permanence of Paper).

For Dan and Anna

Contents

PROLOGUE   Inhale: The Meaning of a Breath

PART 1  ∙  Holding Our Breath

ONE   The Measure of a Lung: Charting Pollution’s Power

TWO   Ground Zero: Delhi’s Health Emergency

THREE   9,416: Living London’s Diesel Disaster

FOUR   Air You Can Chew: Poland and the Price of Coal

FIVE   Cows, Almonds, Asthma: Crisis in the San Joaquin Valley

SIX   Home Fires Burning: A Paradigm Shifts

PART 2  ∙  Coming Up for Air

SEVEN   To Change a Nation: The Story of America’s Clean Air Act

EIGHT   Reluctant Innovators: Air and the Automakers

NINE   Inch by Inch: L.A.’s Long Road

TEN   Live from the Airpocalypse: China’s Next Revolution

ELEVEN   To Whom Belongs the City?: Berlin Looks Beyond Cars

EPILOGUE   Exhale: What Comes Next

Acknowledgments

Notes

Index

PROLOGUE

Inhale

The Meaning of a Breath

A human breath begins in the deepest reaches of the brain, where—far beneath consciousness—the body’s most basic and essential functions are regulated. Just above the point where the spine meets the skull, tiny receptors detect rising levels of carbon dioxide, then stimulate nearby clumps of neurons. Between 12 and 20 times a minute, perhaps 20,000 times a day, millions of times a year, over and over and over again from the first cry of birth until the very last moment of life, those neurons fire signals ordering the muscles of the diaphragm and rib cage to contract.

Message received, the dome-shaped diaphragm flattens, and the ribs move upward and out. As the chest cavity expands, the pressure within drops, drawing air through the nose and mouth. Down the back of the throat, over the voice box, it follows its path deeper and deeper into the body.

To the naked eye, the lungs are unremarkable hunks of spongy pink tissue. Only when they inflate, puffing up like balloons, but faster and more dramatically, does their uniqueness become apparent. In the stylized illustrations of medical textbooks, a lung looks like an upside-down tree, a symmetrical maze whose branches get smaller and smaller as they divide into more than a million tiny twigs.

It’s up close that the structure’s elegant intricacy comes into focus. Hunched over his microscope, the seventeenth-century Italian anatomist Marcello Malpighi was the first to get a glimpse. Until then, the best medical minds believed air mixed directly with blood inside the lung. What Malpighi discovered is now a biological commonplace, taught to middle schoolers: Inhaled air fills sacs that cluster at the airways’ ends like miniature bunches of grapes. There are some 300 million of these alveoli in a pair of lungs, and their surface area is often likened, in total, to the size of a tennis court. Separated from them by membranes one one-hundredth as thick as a hair, tiny capillaries carry blood low in oxygen and laden with carbon dioxide. The gases rush across the barrier, and oxygen molecules bind to hemoglobin, then whoosh toward the heart, ready to be delivered wherever they are needed.

Like so much about the body, a breath is at once astonishingly simple and magnificently complex, delicately balanced yet highly resilient. Unlike other essential functions, the beating of the heart or the peristalsis of digestion, breath can also be controlled by the conscious mind, when we laugh or speak or hold it in to dive underwater.

The lung, too, is a point of vulnerability. While it has its defenses—the mucus that traps some contaminants, the hairlike cilia that sweep away others—this is the place where the outside world makes its way into the very center of the body, barriers left far behind as the air and whatever it carries come within a whisper of the bloodstream.

Lacking microscopes and an understanding of air’s composition, the ancients struggled to grasp the hows and whys of a function they could plainly see was essential. Aristotle, a physician’s son, believed breathing released heat generated by the vital fires of the soul. It would take millennia to definitively correct such misconceptions, but there was one fact the philosopher and his contemporaries understood well: Our very existence depends upon air. The last act when life comes to a close is the letting out of the breath, wrote Aristotle. And hence, its admission must have been the beginning.¹

* * *

I didn’t think much about the meaning or mechanics of breath when I was growing up. Until I was five, I lived in Fort Lee, New Jersey, in an apartment building overlooking the entrance to the George Washington Bridge. It was, and still is, a notorious traffic choke point, where the New Jersey Turnpike and a tangle of other highways merge into one. Suburbanites commuting to offices in New York sit bumper to bumper with trucks rolling north along the I-95 East Coast corridor, waiting to cross into the city. This was the early 1970s, the dawn of environmental consciousness, a time when American cars were exponentially dirtier than today, their fuel tainted with lead, sulfur, and other dangerous toxins. Along with my peers—the Jennifers, Davids, and Lisas who lived in the building too—I breathed it all in as we ran and jumped in the concrete playground out back.

Years later, in my twenties, I watched crosstown buses lurch by a few stories below my Manhattan apartment, heading into and out of Central Park. When I cleaned, the soot that coated the windowsill blackened big wads of paper towels. It took several goings-over, and a lot of soapy spray, to get the paint on the sill white again.

At 30, I moved to London with the charming Brit who’d stolen my heart. For 18 years, more than half of them with our chatty, energetic daughter, we’ve breathed the diesel fumes that foul the city’s air. London’s pollution is just one piece of a health disaster playing out across Europe, belying the continent’s reputation for environmental progressivism. I can smell the exhaust when I’m out running errands, meeting a friend for coffee, or walking Anna to school, clouds of it billowing into our faces. After a few minutes on a busy road, I often have a mild headache.

For a long time, I saw that awful air as just an annoyance. But as I’ve come to understand pollution’s profound effects on the human body, it’s grown into something more: the focus of nagging worry, a fear for my daughter’s well-being, and my own.

I try my best to protect her, of course. But I can’t change the air that surrounds us, nor wish away our city’s diesel mess. So I find myself veering from anxiety to anger. Landing sometimes, too, at a willful blocking out of the danger, as a parent’s urge to shield a vulnerable child tugs against the reality of an individual’s powerlessness in the face of larger forces. It’s that back-and-forth pull of emotions that set me on the path to writing this book.

What I’ve found since is that the taint my family and I breathe is only one strand of a far bigger story. Around the world, from Fort Lee to Frankfurt, Karachi to California, dirty air causes 7 million early deaths annually,² more than AIDS, diabetes, and traffic accidents combined, making it the single biggest environmental threat to health.³ New data suggests that number may climb even higher, pushing air pollution into the very top tier of global killers.⁴ More than 40 percent of Americans breathe unhealthy levels of pollution.⁵ In Britain, air pollution is second only to smoking as a health risk, causing as many as a fifth of all deaths in my adopted hometown.⁶ Across Europe, it kills more than 15 times as many people as car crashes.⁷ Nothing is as elemental, as essential to human life, as the air we breathe. Yet around the world, in rich countries and poor ones, it is quietly poisoning us.

It’s not just the obvious ailments like asthma and bronchitis. Over the past decade and a half, scientists’ understanding of air pollution’s harms has advanced rapidly, and a powerful body of evidence now links it to a long and growing list of health woes, including heart attacks, strokes, birth defects, many kinds of cancer, dementia, diabetes, and Parkinson’s disease.

Not far from where I grew up, and many years later, researchers took advantage of the natural experiment created when highways in New Jersey and Pennsylvania replaced the old-fashioned tollbooths where we used to hand cash to an attendant or toss coins into a basket with the high-tech kind that charge the fee electronically as you zoom past. The switchover dramatically reduced backups at the collection points, and the researchers found rates of premature birth dropped by about 9 percent for pregnant women within a mile and a quarter radius of where the old booths had been.⁸ While that change was positive, it made clear the disturbing link between the highway exhaust so many of us breathe and a pregnancy outcome that can have lifelong consequences for babies born early.

I’m lucky enough to have been in good health all my life. And when, sooner or later, illness comes along, I won’t know whether the pollution I’ve taken in over the years has had anything to do with it, or if I should, instead, blame my sweet tooth, my lifelong preference for a good book over a brisk run, or a malevolent gene buried somewhere in my DNA, beyond anyone’s control.

None of us can. And that invisibility is a strange feature of this crisis. You see one person run over in the street and you’ll never forget it, observed a Los Angeles environmentalist I met. But thousands dying from the effects of dirty air will never even faze you.⁹ He was right. When smokers succumb, they know their own actions, and those of the tobacco companies that fed their habit, helped bring about their illness. But, in a world powered by fossil fuels, we all travel from place to place, use electricity, heat our homes, and few of us fully grasp the effects.

The gains that come when air gets cleaner are similarly difficult to see. There’s no doubt reducing pollution saves lives. But those whose years are lengthened, and those who love them, never know it. Emergency room visits are averted and health care dollars stay in pockets, but the line connecting car or power plant regulations with the size of medical budgets isn’t easy to make out.

Once I’d grasped the dimensions of this hiding-in-plain-sight threat, I wanted to see, up close, how it was playing out around the world. And why. Is air pollution an inevitable part of modern life, something we must resign ourselves to living with? Or are there more malign forces at work, too, keeping us wedded to the old, dirty ways of doing things when better alternatives exist? And, most importantly, what would it look like to do things differently, to build a cleaner, healthier world? Has anyone done it, or tried? And how can we get from here to there?

By way of looking for answers, this book tells the story—the stories—of air pollution, and of the people I met whose lives are shaped by it. In the United States, thanks to decades of gradually tightening regulation, air is far cleaner than it once was. But that improvement—now at risk as the rules that brought it about come under assault—has failed to keep up with the science, which tells us more clearly with each new study that even relatively low pollution levels do real damage. Around the world, in fast-growing South Asia and China, in Europe’s coal-burning east and its diesel-dependent west, in Cairo and Johannesburg and Lagos, the problem is much worse.

In Part 1, Holding Our Breath, our itinerary includes Delhi, pollution’s ground zero, where a mother has nightmares about what’s happening inside her children’s lungs, and an eccentric businessman builds himself a clean-air bubble. I’ll show you around London, my window onto the consequences of Europe’s disastrous embrace of diesel. Poland’s story is the story of coal; we’ll meet men hoisting bags of it into their cars and watch an old woman trudge to the basement to scoop some into her furnace. In California’s parched and poor San Joaquin Valley, migraines and wheezing shatter preconceptions that this is just an urban problem. We see there, too, that while dirty air affects everyone who breathes it, some suffer more than others, so this issue is infused with questions of race, class, and fairness.

The news is not all bad. Part 2, Coming Up for Air, finds progress and hope—past, present, and future; grinding and swift; tiny glimmers and potentially seismic shifts. From the still-unfolding story of one of America’s most powerful and important laws, the Clean Air Act—and the friendship that, across party lines, helped to birth it—to China’s world-changing push to find a healthier path. And a search, on the streets of Berlin, for ways to put the needs of human beings before those of the cars that dominate so many of our cities.

Of course, there is action and progress in the polluted places, and still plenty fouling the air of the improving ones. My hope is that these chapters’ global reach will demonstrate both the scale of the problem and the very real opportunity we have to solve it.

In many ways, this is a book about choices. About how we choose the kind of world we want to live in. And about the complexities of an age in which the things that have changed our lives for the better also bring consequences that are harder to see.

Cleaner air, it turns out, is not an impossible dream. We know how to get there, and doing so would bring enormous health benefits, on a par in some places with slashing sugar consumption or getting everybody up off the couch.

And understanding pollution’s hidden dangers holds an even greater power. The overarching challenge of our time, of course, is climate change. But despite the floods and droughts and storms, its risks can still feel abstract and distant, a calculus of parts per million high in the atmosphere, or glaciers melting thousands of miles away. Dirty air, on the other hand—caused by our heedless burning of the very same oil, gas, and coal that are warming the planet—is wreaking its damage in the here and now. Those fuels are woven into the fabric of our societies, and weaning ourselves from them won’t be quick or easy. But once we recognize the toll they are taking, not just on the habitats of polar bears but on our hearts and lungs and those of our children and parents, I hope we’ll see more clearly that a different future is within our grasp.

PART ONE

Holding Our Breath

1

The Measure of a Lung

Charting Pollution’s Power

In a hospital, a bedroom, on a mat laid out on a dirt floor, with a groan and one last push, a child is born. The light, the cold, the noise come as a confusing shock after the warmth of the womb, but one thing is clear and pressing, unfamiliar but primal: a need for air. The fluid that filled the lungs for months has begun to seep away. Now their work must begin—the work of a lifetime, the work of sustaining life. No longer can this child rely on her mother’s lungs, her mother’s heart, her mother’s blood to deliver the oxygen she needs, to whisk away the carbon dioxide that accumulates so quickly. She depends on others in almost every way, but this she must do for herself. Her first try, the first breath, is a gasp, shallow and difficult. But it makes the next one a bit easier, squeezes out a little more of the fluid, inflates the tiny alveoli where oxygen will cross to the bloodstream. Unsteady at first, the new rhythm soon takes hold, the newborn’s chest rising and falling, each breath expanding the lungs a little more. Even deeper within the child’s body, the rush of oxygen resets the pressure in her blood vessels. That change cascades toward her heart, shifts the balance of its pressure, too, soon forces closed a hole that had connected left to right. The old map is redrawn, and the blood follows a new path, as the lungs—until this moment irrelevant, now utterly essential—become a stop on its journey through the body. The breath is getting easier, in and out, again and again, as life in this remarkable new world begins.

Across Southern California, in school gyms and libraries and lunchrooms, the children filed in, one by one, to put their lips around a plastic tube and blow with all their might. Thousands of them, year after year, in rich neighborhoods and poor ones, from the breezy towns along the Pacific coast to the hot, smoggy valley locals know as the Inland Empire. Erika Fields was one of them, back in the 1990s, when she was in high school at Long Beach Poly, just outside Los Angeles. Even now, she’s the kind of person who raises her hand, who steps forward when volunteers are needed, and she liked being the only one called out of her class, walking down the hall to the quiet room where the breathing machine sat on a desk. She liked, too, the sense of being part of something bigger than herself, something that might really matter in the world.

In the empty classroom, the woman from the University of Southern California would hand her a sterile mouthpiece, attached by a tube to the spirometer ready to gauge the power of her lungs. Erika would give it a couple of practice puffs to get comfortable before the one that counted. I remember her saying ‘Push, push, push. Blow all the air out.’ And then she would show me on her laptop, and I could see on a graph where I pushed the most, and watch the line edge downward as her breath tailed off. After that, there was a survey to fill out, a couple of pages about her health and her family, about smoking in the home and pets and diet and exercise, and then Erika would walk back down the hall, back to her classmates and the ordinary rhythms of the school day.

She didn’t know it then, but those brief once-a-year interruptions to her routine helped lay the foundation for insights that would ultimately change scientists’ understanding of what air pollution does to the human body. In the vast stacks of accumulating numbers—results from Erika Fields’s breath tests and thousands of others—a team of patient researchers would discern the outlines of a threat that had, until then, been hard to see.

* * *

Ed Avol was one of those scientists. He grew up breathing the foul air of 1960s L.A., and he remembers well the hacking coughs that filled the playgrounds of his childhood. An engineer by training, he worked early in his career on hospital-based studies that examined the effects of dirty air as researchers had for decades, by pumping pollution into small rooms and watching volunteers exercise inside. The team he was part of wasn’t allowed to make conditions in their smog chambers any worse than what Angelenos would experience outdoors, but in the 1980s that still gave them plenty of latitude. The researchers would monitor subjects as they pedaled, measuring their heart rates and oxygen levels, making note of their coughing, their shortness of breath, and their red, watery eyes. By that time, it was clear to scientists that ozone—the main ingredient in the smog that still plagues L.A. and so many other cities—had an immediate effect on those who breathed it. And the impact could be far more serious than the discomfort Avol saw so plainly: When ozone blankets a city, asthmatics wheeze, emergency room visits spike, and even in healthy people, the lungs can grow inflamed and struggle to do their job.

But Avol had begun to ponder an even bigger question: If ozone’s immediate effects on the body were so clear, what was it doing over the long term to those who breathed it day after day, month after month, from one year to the next, over the course of a lifetime? Did its effects vanish when the air cleared, or had ozone—or, perhaps, some other, less familiar pollutant—wrought unseen damage that would accumulate slowly, lying in wait to bite unexpectedly decades later?

As it happened, John Peters and Duncan Thomas, researchers at USC’s medical school, were wondering the same thing. Concerned with the implications for public health, California’s Air Resources Board, the country’s most aggressive air pollution regulator, had asked them to design a long-term study that would definitively answer that very question. Avol signed on, and the team began, in the early 1990s, to set out the parameters that would guide their effort, to ensure that its long, slow time frame would be rewarded by results of rock-solid reliability.

It was that design that, a few years later, drew Jim Gauderman to the project, known by then as the Children’s Health Study. Gauderman is a biostatistician, schooled in the complex methodologies that sift human truths from vast haystacks of numbers. It’s not just his training that suits him to his work. He speaks in measured tones, weighs his words thoughtfully, has the calm, steady bearing of a man who knows painstaking diligence is sometimes the only route to scientific clarity.

He could see the meticulous groundwork Avol and the others had laid would one day bring a clear answer to a question that ate at him too. Gauderman was also from L.A., and had wondered, since his days as a young cross-country runner, what hidden scars all those training sessions along traffic-clogged roads might have left on him. He and Avol, junior partners at first on a project others had conceived, would eventually become its leaders.

There were many metrics the scientists could have chosen to use, but the one they settled on carried a unique power—the power, in some sense, of life itself. They’d test the strength of children’s lungs, over and over again, year after year. It was a measurement that, at least implicitly, carried a prediction, one that would follow a child forever. For there are few facts about a human body that correlate more closely with its health, with the very length of its life, than the development of its lungs. Weaker lungs mean illness and frailty, and fewer years; stronger ones allow for vitality and longevity. So what Avol and Gauderman were measuring, very literally, were the invisible boundaries being drawn around their subjects’ futures.

For the children, of course, those stories were yet to be written. The team recruited 4,000 of them, kids between 10 and 16, in a dozen towns and neighborhoods as diverse as California itself. Later, they would add more cohorts, bringing the total number of subjects to more than 11,000, the youngest of whom joined as kindergartners and finally aged out of the study when they finished high school in 2015.

It was Gauderman who sifted, day after day, through the data that began pouring in. In addition to the annual lung tests, there were height and weight checks for every participant, and air quality measurements from monitors in the children’s neighborhoods. To a man who knew how to read them, the numbers sketched the outlines of the children’s lives and health, of their bodies and their lungs and the air that filled them.

It was still too soon, though, to find answers to the questions driving this work. While the years went by and the children’s lungs grew, Gauderman would have to watch and wait. Early on, he was mostly looking for errors that might skew the results. Did the paperwork list a child’s height as four feet when he stood last year at five? We would go to the field staff and say, ‘What happened? This kid shrunk a foot, which value is right?’

Eventually, he began searching for patterns. They weren’t easy to make out. Because, of course, all those young lungs were growing, and gaining power, no matter how dirty the air they breathed. Gauderman’s task was to determine whether some were developing more slowly than others. If they were, there could be any number of causes, from genetic predisposition to poor diet or a parent who smoked. Even in the most polluted towns, there would be many children with strong lungs, and in the cleanest places, some would struggle for breath. He would have to use his most sophisticated statistical techniques, and sometimes invent new ones, to decode the message buried in the numbers, to disentangle what mattered from the irrelevant noise. As one millennium ended and another began, as new children joined the study and the older ones trudged down school corridors again and again, as their lungs matured and the data piled higher, the signal grew stronger. Until, eventually, it became undeniable.

There was no eureka moment, no sudden, made-for-TV aha. It wasn’t that kind of science, and Gauderman was not that kind of scientist. The message peering out at him wasn’t what he had expected, so he checked and rechecked, looked at it from every angle, until he was certain what he was seeing was real. In 2004, the answer to the question the team had posed more than a decade earlier appeared, at last, on the pages of the publication reserved for the most consequential of health breakthroughs: the New England Journal of Medicine.

No one would have been surprised, of course, to discover pollution’s effects were long lasting; they wouldn’t have been looking if they hadn’t had an inkling that might be the case. What shocked these careful men was the scale, the sheer force, of the impact. It turned out that, year by year, as their trove of data had grown, the damage was accumulating, too, creating a gap likely to forever haunt the children caught on the wrong side.

By the time the oldest subjects finished high school—when growth was winding down and the consequences had become irreversible—dirty air had left its mark on the lungs of the children who breathed it. Those lungs failed to reach their full power, were weaker than they ought to have been, the very air that had sustained them also holding them back. Pollution had planted a hidden seed of vulnerability in these children, an unseen frailty that would set their futures on a different trajectory than their peers’, would make their bodies less robust and could even, eventually, shorten their lives.

Lungs that are 20 percent weaker than normal are a medical red flag, a warning that will prompt a doctor to hunt for a cause, and hope, especially when the patient is young, to diagnose something treatable. What the Children’s Health Study found was that kids breathing the dirtiest air were nearly five times as likely to experience that level of lost function—almost 8 percent of them in the most polluted places, compared with 1.6 percent in the cleanest ones.¹ For every 100 children who grew up with the worst pollution, in other words, at least 6 would be burdened as a result with a lifelong health problem. Many more, of course, would have a lesser degree of impairment, a smaller wound that would, meaningfully if less dramatically, drain their vigor too. That, Ed Avol recalls, was a wake-up call.

The finding, Avol says now, shattered scientists’ naïve assumption that if air pollution was doing serious, long-term harm, they would have known about it already. In fact, he explained to me, while the impact was profound, its slow, steady accumulation made it hard to spot. That percent, percent and a half per year of lost development, unless you make careful measurements and have careful monitoring information and do some fairly sophisticated data analysis, it doesn’t just jump out at you. Once they did so, pollution’s power was plain to see.

It was the first glimpse of a frightening truth, one whose repercussions went far beyond Southern California. For the unsettling reality the team had uncovered was that, across the country and around the world, the fuels we have built our lives on—the gasoline, the diesel, the coal we burn to travel from place to place, to power our lightbulbs and laptops, to stay warm in winter—are changing our children’s bodies.

There was another surprise in the data too. From the outset, ozone had looked like the prime suspect. Its immediate impact was so clear that if air pollution was doing any long-term damage, the scientists figured, the familiar noxious gas would be to blame. But while its harm was real, ozone was not what was dampening the power of those young lungs. Tiny airborne particles known as PM2.5, so small they are thought to enter the bloodstream and penetrate vital organs, including the brain, were a far more potent danger. Nitrogen dioxide, one of a family of gases known as NOx, also had a powerful effect. In fact, it poured out of cars, trucks, and ships in such close synchronicity with PM2.5 that even Jim Gauderman’s statistical models couldn’t disentangle the two pollutants’ effects.

That wasn’t all. In what may have been their most worrisome discovery, the team found the pollutants were wreaking harm even at levels long assumed to be safe. In the years to come, the implications of that uncomfortable finding would be felt far beyond the pages of prestigious scientific journals.

* * *

Long Beach, where Erika Fields grew up, and where she gave birth to a baby after high school, wasn’t the most polluted of the Children’s Health Study communities, but it was certainly on the wrong end of the scale. Around the time her son was born, she started getting bad colds that would last for days, then clear up in a matter of hours. Eventually, she saw a doctor, who diagnosed allergies and sinus problems and said poor air quality was probably to blame.