Transfer of DDT and metabolites from fruit orchard soils to American robins (Turdus migratorius) twenty years after agricultural use of DDT in Canada.

摘要: Wildlife contamination studies found high levels of DDT and associated metabolites in bird eggs from Canadian orchard sites during the early 1990s. The present study investigated local dietary uptake geographic variability tissue concentrations same orchards. A soil–earthworm–robin food chain was chosen for study, as surveys showed that robins contained highest several avian species because published research indicated earthworms were a probable exposure route. Organochlorine pesticides PCBs measured soil, earthworm, robin egg, nestling samples collected fruit orchards reference sites. High average DDE (soil: 5.2 mg/kg; earthworm: 52 egg: 484 mg/kg dry weight) 9.2 21 73 Okanagan (British Columbia) confirmed previously recorded common region. Concentrations detected Simcoe, Ontario, not but still significantly elevated relative to soils areas. Significant positive linear regressions between soil earthworm consistent trends accumulation suggested acquiring metabolite (DDTr) burdens locally. Low DDTr nests nearby nonorchard post-DDT habitats sources Persistence chains is likely due combination retarded degradation rates its extensive use historically. some at comparable those observed field where mortality or reproductive effects occurred.