Influence of organic acids on aluminium absorption and storage in rat tissues

Six groups of 16 rats each were fed a standard diet for 8 weeks. Aluminium (Al) complexed with organic anions (citrate, lactate, malate or tartrate) was added to the diet of four of the groups and aluminium hydroxide to the diet of one group (control 'Al+'). Aluminium concentrations in the diets were 1500-2000 mg/kg. The sixth group (control 'Al-') served as control. Plasma, bone (femur), kidneys, cerebral cortex and cerebellum levels of aluminium were determined at 4 and 8 weeks. All the complexing agents increased tissue accumulations, compared with values in the two control groups, especially citrate in bone and kidneys and lactate in cerebral cortex. There were no significant differences (P < 0.05) in aluminium levels in the tissues considered between the 'Al+' and 'Al-' control groups. Our results show the ability of dietary organic acids to increase aluminium absorption and tissue accumulation and indicate that concurrent intake of aluminium and dietary organic acids is not appropriate.