Absorption of fluoride following inhalation and ingestion of alginate impression materials

The fluoride (F) contents of ten alginate impression materials in powder form, were found to range from 0.44% to 2.42%. Plasma F concentrations showed no appreciable changes in five dental personnel exposed to aerosols of these powders during routine clinical work. Elevated plasma F levels (120-158 ng/ml) were recorded after ingesting 2 g (approximately 10 mg F) of Zelgan normal-set alginate. The bioavailability of F from the alginate was about 55% of the total F in the administered dose. It is concluded that routine clinical exposure to alginate does not cause any important change in plasma F levels, whereas accidental swallowing of alginate raises the plasma F level significantly.