Fluoride Action Network


Iliac crest biopsies taken from 43 men with industrial fluorosis were compared with control bone samples. The bone fluoride content was determined, histological examinations were made on stained sections and microradiographs, and morphometric analysis performed on the microradiographs alone.

In the subjects with fluorosis, the bone fluoride content (5617 +/- 2143 ppm) was found to be significantly higher (P< 0.00005) than in control subjects (1036 +/- 627 ppm). It decreased slowly, however, after exposure had ceased (to about 50% in 20 years). The histological changes consisted of a nonspecific remodeling activity (resulting in increased trabecular bone volume and cortical porosity as well as hypervascularization and linear formation defects) and modifications of the perilacunar walls (i.e., presence of mottled I lacunae and enlarged lacynae). These histological changes were found more
likely to occur when the bone fluoride content was high but no correlation between the two parameters was observed.

Although certain clinical and radiological data associated with a high urine fluoride content can sometimes establish a diagnosis of skeletal fluorosis, many cases require the use of bone biopsy, which also provides a direct evaluation of the bone fluoride content and can establish the absence of any other bone disease.