EPA has published a research paper on distinguishing intentional releases from natural occurrences and unintentional releases of Bacillus anthracis, which is the bacteria that causes anthrax. The purpose of this research was to: 1) survey the scientific literature to determine the current state of the science regarding the presence of Bacillus anthracis in the environment and outbreaks of anthrax; 2) identify characteristics that would enable a screening of information about outbreaks to rapidly assess whether an intentional release was a likely cause (in U.S. settings); and 3) identify gaps in risk-related knowledge associated with B. anthracis events in the United States. EPA.