The effects of excessive fluoride intake.

A PRELIMINARY report of a fluorosis survey carried out in Tanzania in East Africa was recently published.' That paper was designed mainly to report the high incidence of fluorotic bone changes in certain subjects and it constituted the first proof of naturally occurring bone fluorosis in this region of Africa. The present paper has been produced to give further details of the conduct and other findings of that survey, to discuss the clinical and public health features of fluorosis, and to suggest preventive measures to control this endemic. It also provides a description of the abnormalities found in the teeth, nails, and thyroid gland of 468 children who were not included in the earlier report.