TUESDAY, May 30, 2006 (HealthDay News) -- For 11 straight days, Mizu crawled along precarious "I" beams and threaded her way through smoldering debris, looking for the bodies of people who did not survive the Sept. 11, 2001, terrorist attacks on the World Trade Center in New York City.
A veteran of rescue efforts following earthquakes in Turkey and Armenia, as well as the Columbia space shuttle explosion, Mizu, an 10-year-old German shepherd search-and-rescue dog, had never experienced anything like the fires, the gases and noxious debris cloud that threatened to consume all rescue workers -- human and canine alike.
But unlike humans on the scene, Mizu could not wear a gas mask or safety goggles to protect her from carcinogens. She needed her nose to work.
And it's the health of that nose and her respiratory system that researchers are now studying, because they could yield valuable clues to any pending health threats facing humans who were part of the massive rescue operation.
"These dogs spent all this time in there just breathing. They're like the canary in the coal mine," said Mizu's human partner, Billy Kidd, a firefighter with the Miami-Dade (Fla.) Fire Rescue's aviation unit.
The University of Pennsylvania, the Iams Company and the American Kennel Club Canine Health Foundation are sponsoring a five-year study to investigate the health of 12 search-and-rescue dogs who were on site at the Pentagon and at the Twin Towers after the attacks. It's the first study of its kind.
The dogs' welfare is crucial, because search-and-rescue canines often don't live very long and can experience debilitating health effects from their work. After the 1999 earthquake in Izmit, Turkey, one dog snorted so much lye that had been poured on dead bodies that he bled out of his nasal passages.
But the health of humans is, of course, of paramount concern.
"We do have humans who were subjected to the same conditions as the dogs, so, of course, we want there to be some application that we could move over," said Dr. Amy Dicke, a technical services veterinarian at The Iams Co., a pet food maker. "Dogs have an increased metabolic rate compared to humans, so they often show signs earlier than a human when exposed to the same carcinogens. This may serve as an indicator of health patterns in humans experiencing the same conditions."
So far, the news is good. All the dogs have undergone intensive blood work, chest X-rays and magnetic resonance imaging, and none shows any signs of nasal or respiratory cancer related to 9/11, Dicke said.
Health experts hope this will be good news for humans exposed to the same brew of carcinogens unleashed by the terrorist attacks. Right now, however, it's too soon to have information about "any unusual occurrence of disease" in humans, said a spokesperson with the New York City Department of Health.
However, survivors of the World Trade Center disaster have recorded other health problems, most of them respiratory and psychological.
New data from the World Trade Center Health Registry found that 57 percent of 8,500 survivors reported new or worsened respiratory symptoms. Survivors caught in the dust cloud caused by the collapse of the Twin Towers were twice as likely to report newly diagnosed asthma than those not exposed to the cloud.
In April, a coroner in New Jersey made the first apparent ruling linking a death to cleanup work at the World Trade Center site. James Zadroga was a 34-year-old police detective who developed respiratory disease after working 470 hours at the site. He died in January of respiratory failure.
The Iams study still has another year to go, and the University of Pennsylvania is doing a larger study with about 100 animals, Dicke said.
As for Mizu, Kidd said he's amazed his partner is still alive. "Most disaster dogs are dead by 7 or 8 because of the hazardous environments that they work in, and the wear and tear on the body," he said.
Mizu, however, is still going strong, Kidd said.
Visit the World Trade Center Health Registry for more on the health issues facing 9/11 survivors.