What to know
- World Trade Center (WTC) Health Program-funded research has increased understanding of health effects among adults exposed to the events of September 11, 2001, or 9/11.
- Additional research could help us better understand the possible health effects among those who were 21 years or younger at the time of their 9/11 exposure.
- A research coordinating center that engages with the 9/11 community is an important first step in addressing this need.

Summary
The events of September 11, 2001, exposed responders and community members to a complex environmental disaster including a mixture of airborne contaminants.
Since 2011, the World Trade Center (WTC) Health Program has funded research of the 9/11-exposed population. This research has increased our understanding of health effects related to 9/11, ultimately providing a pathway to improved health care for people affected by 9/11 exposure.
Most of the research done thus far has focused on individuals exposed as adults. Much less is known about individuals exposed to 9/11 while their mother was pregnant with them, in utero, or while they were children, teenagers, or young adults. A recently published commentary1 discusses the importance of addressing this knowledge gap through new research studies.
What Do We Know?
More than 1,500 scientific publications have documented health effects among 9/11-exposed populations. These include health effects involving the lungs and upper respiratory tract, the stomach and esophagus, different types of cancers, mental health disorders, and others. Only a small percentage of those publications have focused on individuals potentially exposed at a young age.
To address this need, the U.S. Congress directed the WTC Health Program Administrator to establish a new research cohort, or group of people, willing to participate in studies. Research involving this cohort will focus on the health and educational impacts of 9/11 on individuals exposed at a young age.
Why Is This Important?
Among WTC survivors, those exposed to 9/11 in utero or as children, teenagers, or young adults are a unique population. They experience larger exposures relative to their body size and process and eliminate harmful chemicals less well. Adverse health effects also are more likely to occur during the rapid growth and development common to all children and young adults. These and other factors help explain why younger populations can develop different health effects compared to those seen in adults.
A better understanding of how 9/11 exposures in early life contribute to these and other health outcomes is important as we work to address the true impact of 9/11 across all ages.
Research On Early Life Exposure To 9/11
Research among those exposed to 9/11 in early life requires overcoming unique challenges presented by studying health effects decades after the event. By emphasizing active and ongoing community engagement, a research coordinating center can address these challenges. Partnerships among researchers, community members, public health agencies, clinicians, and others will be essential to ensure meaningful results, scientific accuracy, and public trust.
Looking Forward
As we approach the 25th commemoration of 9/11, the WTC Health Program remains committed to providing high-quality, compassionate medical monitoring and treatment for WTC-related conditions. It is also committed to funding research on physical and mental health conditions potentially related to 9/11 exposures. By creating a new research coordinating center, the WTC Health Program is taking important steps to expand our knowledge about the health effects of those exposed to the WTC disaster at a young age.
If you were 21 years or younger when you were exposed to 9/11, or you are interested in learning more about this effort, sign up to receive emails on its progress. As soon as it is available we will share information on how and when you can get involved. If you know someone exposed to 9/11 when they were 21 years or younger, please forward this information to them.
Author Information
Douglas Trout, MD, is a physician in the World Trade Center Health Program.
CAPT Mateusz Karwowski, MD, MPH, is Chief of the Research and Evaluation Branch in the World Trade Center Health Program and a medical officer in the U.S. Public Health Service Commissioned Corps.
RDML Lisa Delaney, MS, CIH, is Director of the World Trade Center Health Program and Assistant Surgeon General in the U.S. Public Health Service Commissioned Corps.
John Howard, MD, is Administrator of the World Trade Center Health Program.
This page was last updated on this date. Updates may include minor edits, image changes, or other modifications to page content.
The information on this page was last reviewed by subject matter experts to ensure accuracy.
- Reibman J, Trout D, Karwowski M, Wilson L, and Howard J [2026]. “Health Impacts of the World Trade Center Disaster—A Call to Study Those Exposed at a Young Age.” American Journal of Industrial Medicine 69: 696-698. https://pmc.ncbi.nlm.nih.gov/articles/PMC13456341/