Exposure to high levels of polychlorinated biphenyl (PCB), an environmental toxin, is associated with higher levels of dangerous visceral abdominal fat, shows a new Uppsala University study. By analyzing data from the Prospective Investigation of the Vasculature in Uppsala Seniors study of more than 1,000 70-year-old Uppsala residents, the researchers initially found an association between the presence of higher levels of PCB and the development of diabetes. The current study used magnetic imaging to determine the amounts and location of fat stores in 300 of the study participants. The results showed that a high proportion of abdominal fat was found in those with high blood levels of the highly chlorinated compound PCB189. Visceral abdominal fat has been linked with a higher incidence of type 2 diabetes. More research is needed to understand how PCB contributes to the development of diabetes and the tendency to store abdominal fat.