PH11 Bioaccumulation and Biotransformation of POPs
Exhibit Hall
8:00 AM - Thursday, 13 November 2003
(PH106) Principle component analysis of PCB congener profiles in passerines and their diet.
Neigh, A1, Newsted, J2, Kay, D2, Zwiernik, M1, 2, Blankenship, A2, MacCarroll, M1, Ruppert, C1, 2, Bradley, P1, Park, C1, Giesy, J1, 2, 1 Michigan State University, E. Lansing, MI, 488242 Entrix, Inc., Okemos, MI, 48864
ABSTRACT- Principle component analysis (PCA) is a statistical ordination method that can be used to identify groups of inter-related variables in large data sets. In this study, PCA was used to evaluate PCB congener profiles in tree swallow (Tachycineta bicolor) and house wren (Troglodytes aedon) adults, nestlings, eggs, and diet at a PCB contaminated site within the Kalamazoo River, MI. The importance of identifying pattern composition differences among trophic levels is a critical component in understanding metabolism, accumulation, and biomagnification of PCBs in a contaminated ecosystem. An analysis was conducted to determine whether PCB congener patterns of adults, nestlings, and eggs associate with their position in the life-cycle. The study examines the role of selective accumulation and metabolism of PCB profiles in nestlings and adults by a profile comparison of co-located dietary items, bolus, and stomach contents. Average total PCB concentrations in adult passerines (6.7 mg/kg w.w.) were highest for all samples, while insects had total PCB concentrations of 0.5 mg/kg w.w. Initial analysis of log transformed data suggest >70% of the variation in samples across life stages can be explained by 4 factors with >40% of the variation described by the first factor. Dietary items had good separation from passerine samples based on the first factor due to the primary loading of lower chlorinated congeners. This data suggests that patterns associated with life-cycle stages are more similar to each other than with patterns of dietary items.
Key words: PCBs, Principle component analysis, Tachycineta bicolor, Congener patterns