Even now, more than seven years later, images of that day remain frightfully raw, in large measure because a legion of photographers and journalists made the unimaginable events of September 11, 2001, all too real. Some happened to be in lower Manhattan when the first plane struck that morning. Some arrived as the first tower collapsed. Others called in favors so they could slip under police barricades or fly over the debris pile while the fires raged. All of them considered themselves lucky to have been able to get so close to the biggest story of their lives.

But their luck also marked them. Being close enough to the tragedy to capture the horror put them close enough to breathe in the dust that exploded with hurricane force from the obliterated towers. Close enough to have the dust work its way into their bodies just as the images of that day worked their way into their minds and hearts.

Several scientific studies have linked the dust—as corrosive as drain cleaner—to a range of medical problems, some chronic and some life-threatening. The tsunami of dust engulfed everyone who was there that day. Some were left with disabilities that curtailed or ended their careers. Some carry physical and emotional scars that they rarely speak about.

Gary Fabiano, a freelance photographer, had been downtown shooting polling booths for what had started out as primary-election day in New York. He was heading back to his agency’s office when a call came in on his cell, and he turned right around. He got so close to the towers that when he looked up, he could not see the top of the building coming down at him. But he heard it. “It was like an avalanche of steel and concrete, the steel snapping, the concrete grinding,” he says. “It went completely black, then dead silent.”

Fabiano and a New York City firefighter tried to outrun the dust cloud. They took shelter in the loading dock of 7 World Trade Center, a building that hours later would also collapse. “There was so much soot and what the fireman told me was pure asbestos in the air we were breathing,” he says. “If you took vacuum bags, filled them up with dust and emptied them down your throat, that’s pretty much what it felt like.”

Besides tons of ground-up concrete, the 9/11 dust clouds contained a toxic brew of compounds—including asbestos, lead, benzene, and mercury—that scientists continue to study. What we know so far is that exposure, even for a relatively short time, could burn breathing passages and cause permanent damage. The dust contaminated lungs and could lead to scarring diseases, like fibrosis and sarcoidosis. While the scientific link between dust and disease has not yet been proven with absolute certainty, the dust has been connected to underweight babies born in lower Manhattan, and to a sharp increase in asthma among adults. And the fallout hasn’t been limited to physical ailments. A high percentage of individuals caught in the dust cloud developed post-traumatic stress.

Of course, ground-zero journalists are not alone in falling victim to the dust. Hundreds of uniformed responders—police and fire and emergency medical technicians—have left their jobs on permanent disability. Thousands of construction workers who cleared the site, most of the time without the protection of any kind of respirator mask, are suing the city because they got sick. And for thousands who lived, worked, or went to school in the shell-shocked neighborhoods of lower Manhattan, the dust infiltrated nearly every inch of their lives.

Anthony Depalma , a reporter and foreign correspondent for The New York Times for more than twenty years, is now writer-in-residence at Seton Hall University. He is writing a book about the aftermath of 9/11.