Provided are systems, methods, and media for identifying and purging unwanted contacts. An example method includes monitoring electronic group communication that is conducted between two or more people and building a persona profile for a person of the electronic group communication during a first period of time based, at least in part, on extracting during the first period of time, from the monitored electronic group communication, behavior data associated with a first contact number. The method includes detecting, during a second period of time, whether the person associated with the first contact number has changed. The method includes transmitting an alert to at least one person of the two or more people indicating that the person associated with the first contact number has changed.