The influence of the interaction of fluoride (F) and aluminum (Al) on bioavailability in bacterial and mammalian systems

Fluoride and aluminum, which are known to form a strong complex, are both present in finished drinking water. The effect of F and Al on one another's tissue accumulation was determined using adult, male New-Zealand white rabbits. Fluoride accumulation in plasma, urine, incisors and tibia was increased as the F addition to the drinking water increased within groups receiving a single concentration of Al. In contrast, F accumulation in plasma, urine, incisors and tibia decreased as the Al concentration increased within groups receiving a single F concentration. In addition, Al levels of plasma and tibia were significantly increased by the addition of F to the drinking water, even in animals receiving no Al in their drinking water. Therefore, some of the toxicity associated with high F level might in fact be associated with Al or a combined form of F and Al.Because in vivo studies have shown that F causes the co-accumulation of Al in bone, we determined the interactive effect of these two agents on bone turnover and accumulation in mouse calvarial culture. The combination of F and Al increases alkaline phosphatase activity in calvaria. However, the co-accumulation of Al in bone treated with F that we reported using in an in vivo system could not be confirmed using a calvaria culture system, due to high non-specific adsorption of Al.Further, the effect of Al on F uptake and mutagenicity in Salmonella typhymurium TA98 has been determined and any effect of Al on Ames test results for F was also determined. Intracellular F was below the limit of detection (0.2 ppm). However, F was taken up from media, providing that Al was also present. Neither F, Al, nor Al:F was found to be mutagenic as assessed by a modification of the Ames standard plate incorporation assay. While F did not appear to cause mutations in the presence or absence of Al, it was concluded that the mutagenicity test, using TA98, is not suitable for the evaluation of F mutagenicity.U of I OnlyETDs are only available to UIUC Users without author permissio