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Toxicity of white phosphorus to waterfowl: Acute exposure in mallards

D. W. Sparling·M. Gustafson·P. Klein·N. Karouna-Renier
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Abstract

As part of an effort to understand extensive, white phosphorus (P4)-induced waterfowl mortality at Eagle River Flats, Fort Richardson, Alaska, we conducted a number of acute toxicity tests using penned mallards (Anas platyrhynchos) in 1993 and 1994. The 24-hr median lethal dose (LD50) for P4 dissolved in oil was 6.46 mg/kg in adult males and 6.96 mg/kg in adult females. Although the median lethal doses were not statistically different, the female dose-response curve had a statistically shallower slope than that of males. The LD50 for the ecologically more relevant pelletized form of P4 in adult males was 4.05 mg/kg. In mallards, one mechanism of P4 toxicity caused rapid (3 to 10 hr) mortality and had signs consistent with anoxia. A second, slower acting mechanism resulted in hepatic and renal pathology including extensive fat deposition in the liver and cellular necrosis. White phosphorus accumulated in adipose tissues, but only for a few days.

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BibTeXRIS

D. W. Sparling, M. Gustafson, P. Klein, N. Karouna-Renier. 1997. Toxicity of white phosphorus to waterfowl: Acute exposure in mallards. https://doi.org/10.7589/0090-3558-33.2.187

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