As part of the desperate search to find an explanation as to why fifteen-year-old Charles Bishop flew a stolen single-engine Cessna into a Tampa high rise earlier this month, health officials are now testing the teenager's liver for mercury poisoning. The analysis comes at the request of a mercury exposure expert, professor emeritus of earth and space sciences at the University of Washington in Seattle, John T.A. Ely. Dental fillings and contaminated fish are the leading causes of mercury poisoning, which Ely claims can cause suicidal tendencies.

Officials with the U.S. Centers for Disease Control and Prevention (CDC) say mercury has not been conclusively linked to depression. At one time, authorities believed Bishop's suicide may have been associated with Accutane, an acne medication known to induce depression. However, toxicology tests did not detect Accutane in Bishop's blood. Tests for drugs and alcohol were also negative.