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September 8, 2006

Q&A: Assessing the Health of Clean-Up and Recovery Workers at Ground Zero

Three weeks after the Sept. 11, 2001, terrorist attacks on the World Trade Center, Alison S. Geyh, PhD, assistant professor in Environmental Health Sciences, led a team from the Bloomberg School that traveled to New York to monitor exposure of cleanup workers at Ground Zero. In comparison with groups defined as first responders? fire and police personnel and medical workers? the health effects of this population has not been closely studied.

Geyh’s team returned to the disaster site two more times to collect additional data on workers’ exposure to site debris and also to assess their respiratory health status. The work, funded by the National Institute of Environmental Health Sciences, has resulted in several studies that have contributed significantly to the scientific literature on the Sept. 11 attacks.

For Geyh and her colleagues the work at Ground Zero was grueling. It meant 20-hour days, carrying heavy sampling equipment to the site and grabbing meals at the Red Cross comfort station.

She is currently seeking funding for more follow-up studies on cleanup and recovery workers at the disaster site. “We’d like to know how they’re doing at the 5-year point,” she says. “It’s seeming more and more clear that people continue to have health problems.” Jackie Powder with the Office of Communications and Public Affairs, spoke with Alison Geyh, an assistant professor of Environmental Health Sciences.

Question: You spent most of October 2001at Ground Zero and some time there in April of 2002 monitoring the exposure of cleanup crews to airborne debris at the disaster site. What did your work involve and what did you find?

Answer: We measured concentrations of airborne particles, as well as airborne asbestos and volatile organic compounds, directly on the disaster site. With the particle measurements, we did it in a way that allowed us to say something about the different sizes of particles that workers were exposed to. What we found was that people were exposed to large particles, as had been reported in the press, but there were also days at the site when small particles dominated the airborne concentrations. We interpreted that to mean that the fires, which burned through December, were driving the exposure on those days, and on other days it was driven by debris removal activities. Our data gives us a sense of dynamic exposure from a particle standpoint, and there is reason to be concerned about exposure to both large and small particles.

Question: How did this differ from other monitoring that took place at the site?

Answer: OSHA did some monitoring of workers on site, and EPA measured airborne pollutant levels in the surrounding area. What we did was different in the context of what other groups were doing to address this health issue, because we reached out to people with the specific purpose of trying to quantitatively assess the relationship between being at the disaster site and having health problems long after leaving.

Julie Herbstman at Ground Zero, 2001

Shortly after 9/11, Julie Herbstrom,
MSc student in Epidemiology, attaches
an air monitor to a Ground Zero worker.

Question: How did the experiences of the truck drivers you worked with differ from those of first responders?

Answer: We didn’t have any direct contact with firefighters, but the truck drivers felt their experiences were different from several standpoints. They felt they weren’t receiving adequate physical protection. Although there were a lot of respirators at the site, people didn’t seem to know how to get a hold of them, and once they got them they didn’t know what to do with them.

They also talked about not knowing what to do when they saw a body part in their trucks. This isn’t a group of people who have had any emergency response training. They’re coming to the site with a background in building buildings and hauling concrete. One guy described that when he dumped a load of debris a hand came out and he wasn’t able to get that out of his mind. He explained how he stopped and made sure the hand was appropriately taken care of, but it was clearly a very traumatic thing for him.

Question: What were the results of a respiratory health assessment that your team conducted in 2001 on a group that included heavy equipment operators, laborers and carpenters, as well as truck drivers

Answer: Among those who said they were symptom-free before starting work at the site (65 percent) a significant number reported a new cough and new phlegm production. We also found that a large percentage reported having a new wheeze, which was something our pulmonologist didn’t expect to see develop over a three-month time frame. It’s an indication of lung inflammation and could indicate that the person is in the process of developing asthma.

Question: What did you learn about longer-term psychological effects of working at the site, based on union workers’ responses to a mail survey sent out in May 2003, 20 months after the attacks?

Answer: There’s an indication of having elevated levels of post-traumatic stress disorder. One of the things we did very right was to allow people a forum for expressing themselves in the survey. We were then able to take some of that personal testimony and write about it, and write about it in a way that I hope will be helpful should we ever have to deal with something like this again. Some of the workers were not able to deal with the experience of being involved at the WTC, and for others it was the shining moment of their lives.

Question: What are some of your memories of being at Ground Zero?

Answer: The first moments at the site I just couldn’t process what I was seeing; it was like you went off the planet. I came away from the first day feeling that I had done a very good job of not falling apart—and then three days later I fell apart. Although we didn’t really talk about this, it became clear after we’d been there for awhile that going back and forth and coming and going from the site was very difficult. It was very painful to be in the real world we understood and then be someplace where there were no touchstones.

Question: Are there any lessons that can be learned about how to respond to potential future disasters?

Answer: Very early on there needs to be some organized effort to give people emergency preparedness or response training, and build that function into the disaster response protocol. First responders are traditionally police, firefighters and medical people, but in this case the group that responded first was everybody.

The other thing I think we’ve learned is that you need to have a group of people who are not going to be involved with the emergency response and who are more involved with keeping track of who is there, what they’re doing and how long they’re doing it. We’re talking about a team of environmental epidemiologists and exposure assessors whose sole purpose doesn’t seem at all useful right off the bat. But without having the folks who know how to do this in a rigorous and formal way, what happens afterward is an ad hoc mish-mash. For example, we believe that one of the biggest hazards at the site was inhalation exposure, and of course the biggest exposure was at the beginning. But there are no measurements of particle concentrations or anything from that time.

There needs to be a long-term commitment and funding right up front to track people involved in a disaster response for 10 years. You might find everybody’s fine and that would be great, but we can’t assume that if we track people for a short time we can answer all the questions we need to answer.

Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Kenna Lowe or Tim Parsons at 410-955-6878 or