PARENT SESSION
PS10 - Immunotoxicity
Sunday, 17 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P119) Effects of DDT Exposure on Immune Response in American Robins from Orchards of the Okanagan Valley, British Columbia.
Smith, Lori*,1, Elliott, John1,2, Wilson, Laurie2, Cheng, Kim1, 1 University of British Columbia, Vancouver, British Columbia, Canada2 Canadian Wildlife Service, Delta, British Columbia, Canada
ABSTRACT- DDT and other pesticides have been shown to have detrimental effects on the immune system. These chemicals can trigger changes in lymphoid tissues and alter the non-specific, humoral, and cell-mediated immune responses of a variety of organisms, including birds. American Robins (Turdus migratorius) from the Okanagan Valley (OK) of British Columbia, Canada were studied in order to determine the effects of in ovo and early post-hatch DDT exposure on the immune system. Robin eggs from this area have been shown to be contaminated with high concentrations of DDT and DDE (up to 277.62 
g/g 
DDT), despite the fact that the use of DDT was discontinued nearly thirty years ago. Blood smears were collected from 160 OK robins (male and female) at ten days of age for the purpose of conducting differential white blood cell counts. Smears from 95 chicks collected from 'clean' areas in the Lower Mainland (LM) of British Columbia were used as controls. In order to determine T-lymphocyte mediated immunity 13 LM and 13 OK adult males were subjected to the phytohemagluttinin (PHA) skin test, as well as 45 LM and 73 OK nestlings. Antibody response was tested in the adult males by challenging the birds with sheep red blood cells (SRBC) and measuring the resulting production of antibodies. Preliminary results revealed no significant differences (p > 0.05) between LM and OK males in response to the PHA test. Further analyses will reveal if this holds true in the nestling birds and whether DDT contamination has an effect on other aspects of the immune system studied.
Key words: DDT, immunity, American robin, DDE