In 2001, a population-based cross-sectional study was conducted to compare levels of total polychlorinated biphenyls (PCBs) in residents of Calcasieu Parish and Lafayette Parish, Louisiana. A demographic, lifestyle, and food consumption questionnaire was collected for each participant. Overall, weighted geometric means and medians of total serum PCB concentrations in residents of Calcasieu and Lafayette Parishes were similar among all risk subgroups. However, 15-29 year olds had higher total serum PCB weighted geometric means in Calcasieu (64.4 ppb) than did this age group in Lafayette (46.6 ppb) (p=0.0059); conversely, in the 60 and older age group, geometric means of 293.7 ppb and 392.5 ppb were observed for Calcasieu and Lafayette, respectively (p=0.0059). In general, total PCB serum levels in Calcasieu and in Lafayette Parish, Louisiana residents were similar to each other and to levels observed in the U.S. general population in this time period.