The World Trade Center Health Registry was established in 2002 by ATSDR and the New York City Department of Health and Mental Hygiene to track the long-term physical and mental health effects of the September 11 attacks . The registry contains more than 71,000 people who lived , worked , or went to school near the World Trade Center site , as well as emergency response personnel who were involved in rescue and recovery efforts . It is the largest post-disaster health registry in the United States . Researchers use the registry to study the health effects of the disaster and to develop public health recommendations for future disasters . A 2009 study based on registry data found that posttraumatic stress disorder and asthma were the two most commonly reported conditions among registry participants 5 to 6 years after the disaster . The study found that 19 % of adult participants reported new posttraumatic stress symptoms , and 10 % of adult participants reported developing new asthma
September 11 attacks
September 11 attacks
Agency for Toxic Substances and Disease Registry