PARENT SESSION
MA8 - Ecological Aspects of PCB Interactions
Chair: Gendusa, Tony1, 1 20200 Wambli Lane, Huson, Huson, USA
Co-chair: Zwiernik, Mathew2, 2 224 National Food Safety and Toxicology Blvd., East Lansing, MI, USA
8:00 AM to 12:00 PM - Monday, 18 November 2002
Room Ballroom C
(237) Differential Passerine Sensitivity to PCBs: A Comparison of Somatic Indices and Measurement Endpoints.
Henshel, Diane*,1, Sparks, Daniel2, 1 Indiana University, Bloomington, IN, USA2 US Fish and Wildlife Service, Bloomington, IN, USA
ABSTRACT- The relative PCB sensitivity of nestlings of five passerine species were compared. The five species evaluated, eastern bluebird (BB), carolina chickadee (CC), house wren (HW), red-winged black bird (RW), and tree swallow (TS), were collected just prior to fledging from nestboxes, or nearby nests (RW), placed at the reference site or one of five PCB-contaminated sites. Not all species were able to be collected from all sites. One nestling from each nest was used to evaluate nestling PCB concentrations, and these values were used for all of the sibling nestlings, individually or pooled by nest. Endpoints used for the evaluation included body weight, organ somatic indices and beak, leg and wing measurements. Statistical results were assessed using SAS PROC GLM for the comparison across the sites, and SAS PROC REG in order to determine the equations describing the relationship between total PCBs and each significantly correlated endpoint. In general, body weights for each of the species decreased at the more contaminated sites compared to body weights at the reference (GP) site. Mean weights of male nestlings were larger than females for virtually every species. The number of siblings in the nest played a significant role in the body weights of all species but the carolina chickadees. Of the organ somatic indices evaluated (adrenals, brain, bursa, heart, kidneys, liver, lung, pancreas, stomach, thyroids), only brain, heart, kidneys, lung, pancreas, stomach, and thyroid varied significantly (p < 0.05) or nearly significantly (0.05 < p < 0.1) by site or with total PCBs for at least one species. However, there were differences in the patterns of the direction of the change in the somatic indices (increased or decreased with increasing PCB exposure) between the different species. Of the organ somatic indices, only heart SI consistently decreased across the species with increasing PCB exposure. Of the measurements evaluated, at least some measurements of the beak, wing and leg significantly varied by site or with total PCBs for all species but HW. When compared by age, only RW showed significant age effects on measurements normalized by body weight. Our results indicate that no single passerine species, and especially not tree swallow, fully represents the response characteristics observed in these five species.
Key words: avian, development, heart, brain