Embryo Toxicity of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin to the Wood Duck (Aix sponsa)

• Published in: Archives of environmental contamination and toxicology 2008-11, Vol.55 (4), p.659-669
• Main Authors: Augspurger, T. P, Tillitt, D. E, Bursian, S. J, Fitzgerald, S. D, Hinton, D. E, Di Giulio, R. T
• Format: Article
• Language: English
• Subjects: Abnormalities, Drug-Induced; Aix sponsa; Animal, plant and microbial ecology; Animals; Anseriformes; Applied ecology; Aquatic birds; Biological and medical sciences; Chickens; Cytochrome P-450 CYP1A1 - biosynthesis; Dioxins; Dose-Response Relationship, Drug; Ducks; Ducks - physiology; Earth and Environmental Science; Ecotoxicology; Ecotoxicology, biological effects of pollution; Eggs; Embryo, Nonmammalian - drug effects; Embryo, Nonmammalian - embryology; Embryonic Development - drug effects; Embryos; Environment; Environmental Chemistry; Environmental Health; Environmental Pollutants - toxicity; Environmental research; Enzyme Induction; Fundamental and applied biological sciences. Psychology; Gallus; General aspects; Histology; Immunoenzyme Techniques; Incubation; Lethal Dose 50; Liver - drug effects; Liver - enzymology; Microsomes, Liver - drug effects; Microsomes, Liver - enzymology; Monitoring/Environmental Analysis; Mortality; Organ Size - drug effects; PCB; Pollution; Polychlorinated biphenyls; Polychlorinated Dibenzodioxins - toxicity; Poultry; Risk Assessment; Sensitivity and Specificity; Soil Science & Conservation; Species Specificity; Studies; TCDD; Teratogens - toxicity; Thyroid gland; Toxicants; Toxicity; Waterfowl; Wildfowl
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/s00244-008-9198-2

We examined the sensitivity of the wood duck (Aix sponsa) embryo to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by injecting the toxicant into their eggs. Six groups of wood duck eggs (n = 35 to 211 per trial) were injected with 0 to 4600 pg TCDD/g egg between 2003 and 2005. Injections were made into yolk prior to incubation, and eggs were subsequently incubated and assessed weekly for mortality. Significant TCDD-induced mortality was not observed through day 25 (90% of incubation). Liver, heart, eye, and brain histology were generally unremarkable. Hepatic ethoxyresorufin-O-deethylase activity, a biomarker of dioxin-like compound exposure, was induced by 12-fold in the 4600 pg/g treatment relative to controls. The median lethal dose for chicken (Gallus domesticus) eggs we dosed identically to wood duck eggs was about 100 pg/g, similar to other assessments of chickens. Among dioxin-like compound embryo lethality data for 15 avian genera, the wood duck 4600 pg/g no-observed-effect level ranks near the middle. Because no higher doses were tested, wood ducks may be like other waterfowl (order Anseriformes), which are comparatively tolerant to embryo mortality from polychlorinated dibenzo-p-dioxins and dibenzofurans when exposed by egg injection.