20 years later, fallout grows from WTC dust cloud
Two decades after the twin towers' collapse, people are still coming forward to report illnesses that might be related to the attacks.
Todaythere are more than 111,000 people enrolled in the World Trade Center Health Program, which gives free medical care to people with health problems potentially linked to the dust.
To date, the U.S. has spent $11.7 billion on care and compensation for those exposed to the dust -- about $4.6 billion more than it gave to the families of people killed or injured on Sept. 11, 2001.
More than 40,000 people have gotten payments from a government fund for people with illnesses potentially linked to the attacks.
Scientists still can't say for certain how many people developed health problems as a result of exposure to the tons of pulverized concrete, glass, asbestos and gypsum that fell on Lower Manhattan when the towers fell.
Many people enrolled in the health program have conditions common in the general public, like skin cancer, acid reflux or sleep apnea.
In most situations, there is no test that can tell whether someone's illness is related to the Trade Center dust, or a result of other factors, like smoking, genetics or obesity.
years of research have produced partial answers about 9/11 health problems.
The largest number of people enrolled in the federal health program suffer from chronic inflammation of their sinus or nasal cavities or from reflux disease, a condition that can cause symptoms including heartburn, sore throat and a chronic cough.
The reasons for this are not well understood, but doctors said it could be related to their bodies getting stuck in cycles of chronic inflammation initially triggered by irritation from the dust.
Post Traumatic Stress Disorder has emerged as one of the most common, persistent health conditions, afflicting about 12,500 people enrolled in the health program. Nearly 19,000 enrollees have a mental health problem believed to be linked to the attacks.
More than 4,000 patients have some type of Chronic Obstructive Pulmonary Disease, a family of potentially debilitating breathing problems.
Rates of a few specific types of cancer, including malignant melanoma, thyroid cancer and prostate cancer, have been found to be modestly elevated, but researchers say that could be due to more cases being caught in medical monitoring programs.
One study showed that cancer mortality rates have actually been lower among city firefighters and paramedics exposed to Trade Center dust than for most Americans, possibly because frequent medical screenings caught cancers early.
