daily dose of fluoride in mg per kg body weight =
= (concentration of fluoride in the water in mg per L) * (water intake in liters per kg body weight)
Galagan et al derived an equation for water intake based on temperature:
water intake in L per kg body weight =
= (0.00040423 * (mean maximum temperature in °F)) - 0.0024775
daily dose of fluoride in mg per kg body weight =
= (concentration of fluoride in the water in mg per L) * ((0.00040423 * (mean maximum temperature in °F)) - 0.0024775)
where:
• 1 mg per L is approximately 1 part per million (ppm) since 1 liter weighs 1,000 g.
Limitations:
• Fluid intake would be affected by activity level.
• If a person is in an air conditioned or heated building, the indoor temperature should be used.
• Ingestion of soft drinks and bottled water would be expected to give different fluoride exposure than ingesting tap water.
