EVALUATION OF THE DEVELOPMENTAL NEUROENDOCRINE AND REPRODUCTIVE TOXICOLOGY OF ALUMINUM

Two experiments evaluating functional endpoints pertaining to the deve lopmental neuroendocrine effects of aluminium in the rat are reported. A total of 31 timed mated dams were fed by daily gastric gavage 0, 5, 25, 50, 250, 500 or 1000 mg/kg body weight/day aluminium as a solutio n of aluminium lactate in distilled water from days 5 to 15 of gestati on. The 390 offspring were evaluated for morphological and physiologic al parameters of reproductive functioning, including birth weight, ano genital distance (AGD), timing of vaginal opening, regularity of oestr ous cycles, duration of pseudopregnancy (PSP), number of superovulated oocytes, and gonadal weight. No consistent or reproducible findings s uggestive of toxic effect were found in the parameters of birth weight , AGD, timing of vaginal opening, duration of PSP, number of superovul ated oocytes, and adult gonadal weight. A temporary increase in the pr oportion of aberrant oestrous cycles was detected during the first fou r cycles after vaginal opening, in the 250 mg/body weight/day group, w ith none by the fifth consecutive oestrous cycle. These results sugges t that, apart from a transient disturbance of oestrous cycle regularit y, aluminium does not have a developmental reproductive toxic effect.