THE TOXICITY OF INGESTED CRUDE PETROLEUM OIL TO MARINE BIRDS: PATHOLOGY AND PATHOGENESIS (ANEMIA, ERYTHROCYTE, MFO)

Pollution of the marine environment with petroleum oils has caused extensive morbidity and moratlity in marine birds. Contaminated birds ingest oil while preening. A series of experiments was carried out to identify toxic effects of ingested Prudhoe Bay crude oil in nestling herring gulls (Larus argentatus) and atlantic puffins (Fratercula arctica). Wild-caught birds were brought to the laboratory, maintained on a marine diet and given oral doses of oil. Initial results identified anemia as a toxic effect of oil ingestion and subsequent experiments focussed on the erythron as a target tissue.; Hemolytic anemia with Heinz bodies in red blood cells occurred in gulls and puffins that ingested (GREATERTHEQ) 10 ml oil per kg per day for 4-5 days. Anemia developed precipitously as a hemolytic crisis. Biochemical lesions in affected red cells included membrane lipid peroxidation, methemoglobin formation, an increase in red cell reduced glutathione (GSH), increased plasma membrane permeability to NADH, and a reduction in oxygen-carrying capacity of hemoglobin in excess of that referable to methemoglobin. Structural lesions in red cells included Heinz body formation, anisocytosis, severe distortions of cell shape, plasma membrane crenulation, mineralization of mitochondria, formation of abnormal cytoplasmic vesicles, and both abnormally high and abnormally low cytoplasmic density. These data permitted correlative evaluation of ultrastructural and biochemical changes in red cells experiencing oxidant stress due to oil ingestion. Histological lesions in liver, spleen, kidney, and bone marrow were consistent with intravascular and extravascular hemolysis and a regenerative response. Several other lesions occurred on both oil-dosed and control birds but were significantly more prevalent in the former. These lesions were focal adrenal necrosis, depletion of adrenal lipid, depletion of lymphocytes in thymus and bursa of Fabricius, and virus infection of the bursa of Fabricius. These latter lesions suggested immunosuppression in oil-dosed birds.; In a pilot study, oral doses of disulfiram prevented the usual induction of hepatic mixed-function oxidases caused by ingestion of oil by gulls, and also prevented development of Heinz bodies and of increased GSH in red cells of gulls given large oral doses of oil.