Evaluation of background dioxin-like PCB congener profiles in human serum collected during NHANES 2001/2002 using principal components analysis

With the increasing use of biomonitoring to evaluate human exposure, it is important to understand how the pro file of the congeners of interest in the potentially exposed population compares to the corresponding congener profile associated with background exposure. In this study, we have performed a principal components analysis (PCA) of the 2001/2002 NHANES dioxin-like PCB data for the general U.S. population to determine if the background dioxin-like PCB congener profiles are affected by age, gender, or race. Overall, the results of the PCA indicated that the dioxin-like PCB congener profile for the NHANES participants changes with age and gender. In general, the contributions from PCBs 157, 167, and 169 decrease with increasing age, while the contribution from PCB 118 increases with increasing age. In addition, males are more likely to have higher contributions of PCB 156 than females of the same age. Finally, there were no apparent differences in congener profile by race. These results indicate that age and gender need to be accounted for when PCA is used to compare the dioxin-like PCB congener profiles from the 2001/2002 NHANES data to those of a potentially exposed population.