a Some studies measured the weight (g) of toothpaste ingested which, for a 1,000 ppm F product, would be proportional to the weight (mg) of fluoride ingested.
b No data.
c Toothpaste fluoride concentration = 2,400 ppm. Amounts of fluoride ingested were based on 24-hour urinary excretions and expressed as mg/day, not mg/brushing.
ingestion by children resulting from the use of toothpastes, the products of most interest because of their widespread and frequent use from an early age (Ronis et al., 1993). Dowell (1981) reported that brushing began for nearly 50 percent of his sample by the age of 12 months and that 75 percent had their teeth brushed at 18 months of age. As shown in Table 8-4, children 7 years of age or younger introduce approximately 0.8 mg of fluoride into the mouth with each brushing; the fraction that is swallowed and absorbed (Ekstrand and Ehrnebo, 1980) ranges from about 10 percent to nearly 100 percent. An average of about 0.30 mg of fluoride is ingested with each brushing by young children. Thus, brushing might contribute about 0.6 mg of fluoride daily, especially if a water rinse is not used after brushing. Similar findings were reported by Bruun and Thylstrup (1988), who studied Danish children.