In order to test the hypotheses: (1) that the digestive absorption of fluoride (F) is affected by the presence of aluminum (Al), and (2) that the distribution of F absorbed among organs/tissues is affected by Al, 36 American kestrels (Falco sparverius) were randomly divided into 6 groups of 6, and given oral doses daily for 30 days according to the following scheme: (1) deionized water only, (2) 30 mg/kg F$ sp-$, (3) 24 mg/kg F$ sp-$, (4) 24 mg/kg Al$ sp{3+}$, (5) 30 mg/kg F$ sp-$ + 24 mg/kg Al$ sp{3+},$ (6) 24 mg/kg F$ sp-$ + 24 mg/kg Al$ sp{3+}$. Excreta was collected every 24 hours between dosing. Femurae, kidneys, hearts, alimentary canals, skeletal muscle, and livers were obtained from all birds at the end of experiment. All samples were analyzed for F, Al, total phosphate (P) and calcium (Ca). F excretion was significantly higher in birds given 30 mg/kg F$ sp-$ + 24 mg/kg Al$ sp{3+}$ than in their counterparts which received the same amount of either F or Al alone (p $<$ 0.05). Excretion of Al was also elevated in all groups (except those only given water) from the level of excretion before the experiment commenced (p $<$ 0.05), despite the fact that 2 groups out of those 5 received F only. P and Ca contents of excreta were not affected by the oral dose. F contents in femurae from groups receiving both F and Al were significantly lower compared to those levels in those birds which were given F only (p $<$ 0.05). Significantly more Al was found in kidneys from the group receiving 30 mg/kg F$ sp-$ + 24 mg/kg Al$ sp{3+}$ than in those groups given only 1 of the 2 ions (p $<$ 0.05).

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