Mineral metabolism of rats fed moderate levels of various aluminum compounds for short periods of time.

The effects of ingesting moderate levels of aluminum (5-272 micrograms Al/g diet) were assessed in two short-term (18-d) studies with rats. Rats were fed diets that contained no added aluminum or aluminum lactate, aluminum palmitate, aluminum phosphate or aluminum hydroxide in either reagent grade or desiccated gel forms. The average concentrations of aluminum in the tibias of rats fed 261-272 micrograms Al/g diet were 13.0-15.6 micrograms Al/g fresh weight, while those of control animals were 1.0-1.9 micrograms Al/g fresh weight. Rats fed aluminum accumulated less aluminum in their kidneys and brains than in their tibias. In study 1, animals fed aluminum hydroxide tended to accumulate more aluminum in tissues, i.e., brain, than animals fed the other aluminum compounds. In study 2 the type of aluminum hydroxide fed did not affect the accumulation of aluminum in tissues but rats fed 206 micrograms Al/g diet accumulated less aluminum in their tibias and more aluminum in their kidneys than rats fed 261 and 268 micrograms Al/g diet. Ingestion of these moderate doses of aluminum had no effects on tissue levels of calcium, magnesium and iron of rats and had only small effects on tissue levels of phosphorus, zinc and copper.