CHEMICAL AND X-RAY-ANALYSIS OF FLUORIDE, PHOSPHORUS, AND CALCIUM IN HUMAN FETAL BLOOD AND HARD TISSUES

To evaluate the beneficial effect of prenatal fluoride supplementation , the presence of fluoride in hard tissues in two populations of human foetuses coming from fluoridated (greater than or equal to 0.7 parts/ 10(6) F in drinking water) and non-fluoridated areas (less than or equ al to 0.1 parts/10(6) F in drinking water) were compared by chemical a nalysis and X-ray microanalysis. The fluoride concentrations measured in maternal and venous cord blood confirmed that placental transfer of fluoride was passive when fluoride intake was low. Total fluoride con tents of tooth germs and mandibular bone appeared to increase with flu oride level in drinking water. However, these concentrations were too low to be detected by X-ray microanalysis. Phosphorus and calcium tota l contents were identical in mandibular and femoral bone of both popul ations. In incisor germs, phosphorus and calcium concentrations in ena mel and dentine close to the amelodentinal junction did not differ sig nificantly between the two populations. It is suggested that the low f luoride concentrations in enamel and dentine formed in utero would not have a significant effect on acid solubility. (C) 1997 Elsevier Scien ce Ltd.