What is the fluoride concentration in mouthrinse?

What is the fluoride concentration in mouthrinse?

• A. 226 mg/L
• B. 1000 mg/L
• C. 0.7 mg/L
• D. 0.7 ppm

Answer: (A)

Understanding fluoride content in mouthrinses means converting the stated NaF percentage to the actual fluoride ion concentration. A common rinse uses 0.05% sodium fluoride. This equals 0.05 g NaF per 100 mL, or 0.5 g (500 mg) NaF per liter. The fluoride portion of NaF is about 19/41.99 ≈ 0.452, so the fluoride available per liter is 500 mg × 0.452 ≈ 226 mg/L. Therefore the fluoride concentration is around 226 mg/L. The other values are either much too low for typical rinses or would require a higher NaF content than is common in standard mouthrinses.

Understanding fluoride content in mouthrinses means converting the stated NaF percentage to the actual fluoride ion concentration. A common rinse uses 0.05% sodium fluoride. This equals 0.05 g NaF per 100 mL, or 0.5 g (500 mg) NaF per liter. The fluoride portion of NaF is about 19/41.99 ≈ 0.452, so the fluoride available per liter is 500 mg × 0.452 ≈ 226 mg/L. Therefore the fluoride concentration is around 226 mg/L. The other values are either much too low for typical rinses or would require a higher NaF content than is common in standard mouthrinses.