H.R. 6903, known as the Bruce Vento Ban Asbestos and Prevent Mesothelioma Act of 2008, was introduced by Chairman Gene Green (D-TX) to amend the Toxic Substances Control Act. The bill is intended to reduce the health risks of exposure to asbestos products and help fund public education. The ADAO said that the ban would prohibit the importation, manufacture, processing and distribution of asbestos-containing materials. Critics of asbestos use call attention to the lingering environmental and health concerns of those who responded to the September 11 attack on the World Trade Center in New York. The aftermath of the attack has led to the largest health registry in U.S. history, with more than 71,000 participants signed up for health screening. Participants include first responders, rescue and recovery workers, local residents, area workers, commuters and others. Environmental Health Perspectives, a study published in 2006, examined the results of a five-year assessment of worker health. The World Trade Center Worker and Volunteer Medical Screening Program noted that nearly 70% of WTC rescue and recovery workers suffered respiratory symptoms while working at the site.