BLOOD CHANGES IN MALLARDS EXPOSED TO WHITE PHOSPHORUS

White phosphorus (P-4) has been extensively used by the military for v arious purposes, including marking artillery impacts and as an obscura nt. Target practice in an Alaskan tidal marsh during the last 4 decade s has deposited large amounts of P-4 particles in sediments and water, which have resulted in die-offs of several waterfowl species. Because the toxicity of P-4 in birds has not been well documented and because it is quickly excreted or metabolized in living animals, we sought to determine the effects of experimental dosing on blood characteristics in game farm mallards (Anas platyrhynchos). In two experiments, one e mploying single doses of 5.4 mg P-4 per kilogram body weight in corn o il and the other using daily repeated doses of pelletized P-4 at eithe r 0.5 or 1.0 mg/kg, there were significant changes in aspartate aminot ransferase, alanine aminotransferase, lactate dehydrogenase (LDH), ino rganic P, hematocrit, and hemoglobin. Other indications of exposure in cluded changes in uric acid, creatinine, and total protein, which were consistent with reported liver and kidney damage due to this contamin ant. Changes in white blood cells included a greater frequency of thro mbocytes and fewer lymphocytes in dosed birds compared to controls. A biomarker of exposure based on LDH activity and hemoglobin is proposed .