1984 Volume 22 Issue 1 Pages 33-40
Studies were made on the usefulness of measureing the fluoride con-centration in the serum and urine as an index for the health care of hydrofluoric acid (HF) workers, particulary for those with diminished renal function. Renal clearance of fluoride (CF), the amount of fluoride filtered by the glomeruli per minute (FF) and tubular reabsorption of fluoride (TrF), which were calculated from the serum concentration, as well as the quantity concurrently excreted in the urine and the glomerular filtration rate (GFR), were investigated in patients with chronic renal failure (CRF) and healthy controls after the oral administration of sodium fluoride (as 4 mg F-) with water loading. After the administration the 24-hour excretion of fluoride in the patients with CRF was significantly lower (p<0.0.01) than controls. CF, FF, and TrF were also lower in the patients. CF and creatinine clearance (Ccr) were well correlated (r= +0.87) with CF averaging 48% of the Ccr. Elevated concentrations of fluoride were observed in the serum of patients with CRF and HF workers. Three HF workers who had clinical evidence of renal failure showed a higher level of serum fluoride. However, their urinary level of fluoride showed normal values. The results showed that the urinary excretion of fluoride decreased with the reduction of renal function. Moreover, compared to urinary levels the fluoride concentration in the serum may be a more direct indicator of exposure in patients with kidney hypofunction.
